Digital Painting with KRITA 2.9

Learn All of the Tools to Create Your Next Masterpiece

© 2016 by Scott Petrovic. All rights reserved. This book or any portion thereof may not be reproduced or used in any manner whatsoever without the express written permission of the publisher except for the use of brief quotations in a book review or scholarly journal.

ISBN-13: 978-0-9968517-1-8

Library of Congress Control Number:
2015915715

Published by:
Louvus Media
P.O. Box 29454
St. Louis, MO 63126-8454
http://www.louvus.com

Cover Art:
Tyson Tan

Editor:
Karen L. Tucker

Reviewers:
Wolthera van Hövell tot Westerflier
David Revoy
Raghukamath

Dedication

To my parents, Frank and Jill, as well as my siblings, Paul and John.Thank you for all of your support and encouragement throughout my life. I am a product of all of the hard work and love you have given me. I am so blessed to have an amazing family.

Errata

While I have spent a great deal of time writing, editing, and receiving feedback, there are bound to be errors in this material. If you find errors, or have any other feedback, contact scott@louvus.com.

Acknowledgments

Boudewijn Rempt. You have spent over 10 years of your life making Krita what it is today. Your direction, perseverance, and attitude is the reason Krita has become a tool that so many people are proud to use.

Wolthera van Hövell tot Westerflier. Thank you for spending so much time answering my questions and assisting me. Not only are you a great community leader, but an excellent artist, programmer, and educator.

David Revoy. Your guidance and artistic influence are embedded into Krita’s core. You are an amazing role model, artist, and individual to look up to.

Tyson Tan. You have spent so much time creating the wonderful cover art and assisting the Krita Foundation with all of their projects. I love Kiki.

All of the developers that have contributed to Krita. In an age where many seem to demand money for any contribution, your time and energy are helping the next generation of artists and developers.

The artists featured in this book. This book would be much duller without your creative energy.

Saint Louis Bread Co. (Panera). Much of my writing was done at one of your locations. It was always a joy to get some food, do some writing, and not have to worry about feeling rushed. Thank you for creating an environment for people like me.

Karen L. Tucker. My wonderful editor. After working through this book with you, I realize how much I still need to learn about the English language.

Introduction

Thank you for lending me your precious time. Krita is an application that is designed for digital artists of all kinds. It has been developed for a number of years and has some truly unique features. It prides itself as being a free, open source application. Unlike many other art applications, Krita’s direction isn’t influenced by stockholders and business people focusing on the bottom dollar. Krita is an application that has been nurtured by the artistic community and continues to improve at a dizzying pace.

There are quite a few art education books on the market about digital painting but few about Krita. While there are resources online and Wiki articles, they are written by various authors and can be difficult to wade through.

This past year, I have immersed myself in the Krita community: forums, the Krita chat room, YouTube videos, and social media. The goal was to educate myself on what Krita has to offer. There is a lot of helpful content on the Internet, but it is spread out and at times not accurate. This makes it difficult to find current information.

This book hopes to bring all of the knowledge I have learned under one roof. I hope to share everything I know about the application. After spending so much time with Krita, I believe it has the potential to disrupt the entire graphics industry. Also, a portion of the profits from this book will go toward the Krita Foundation. Your purchase is making Krita better for everyone.

Each chapter covers a different area in the application. You can read this book from cover to cover, but it isn’t designed for this type of consumption. The table of contents is a quick way to skim and find an area you are interested in. If you have never used Krita before, the first few chapters will be valuable for navigating your way around. From there, this book will serve as a good reference when you need to learn more about a specific concept.

Best of luck on your future artistic endeavors,

Scott Petrovic

Downloading and Installing

The safest place to download Krita is from the project website krita.org. When you visit the download page, you will notice that there are different versions of Krita that you can work with. Each version has a different audience in mind. You will probably want Krita Desktop since that works with desktop and laptop computers. This book contains information up through Krita 2.9.7.3.

Krita.org: The latest news is presented in a blog format. You can subscribe to the mailing list if you’re interested in hearing about new releases.

• Krita Desktop – Optimized for nontouch screen devices. This is the version that most people use.
• Krita Gemini – Optimized for devices that can switch between touch screen and nontouch screen. This is only available for purchase on the Steam platform.
• Krita Studio – Commercial version that has paid support. Priority will be given for bug fixes and new features. There are no extra features in this version. The primary operating system for this is CentOS.
  Make sure to download the correct version for your operating system. If you are on a 64-bit operating system, make sure to download the 64-bit version.

Warning for Mac OSX Users

If you are on Mac OSX, you will find some of the features missing or not working correctly. While Krita works well on Windows and Linux, it is not fully functional on a Macintosh. Even though it is not supported, I have heard good things from the community about it working.

If you are on Windows and download an MSI file, it will have an installer that will guide you through the process. There is also a portable version of Krita that doesn’t need an installer file. This means that there is no installation process. You can navigate to the bin (binary) folder. In this case, you can launch the application by clicking on krita.exe. This is nice if you want to run Krita from a USB stick or otherwise make it portable.

Common Issues

There are some common issues that occasionally happen when trying to run Krita. The most common issue has to do with the canvas. The pen pressure might not work, or the canvas might appear black. A common solution is to disable OpenGL. This is done from the main menu Settings > Configure Krita > Display tab. To disable it, uncheck the OpenGL checkbox. OpenGL is a graphics technology that Krita uses. OpenGL is used for canvas rotation and zooming functions. This problem is more common with older computers. Updating your graphics driver fixes this issue many times.

Another common problem is missing user interface elements. If the interface appears to be missing elements, it is easiest to reset the workspace. The icon on the far right of the toolbar allows you to change workspaces.

Using a Graphics Tablet

To get the most out of creating digital art, using some type of pen digitizer, or stylus, is the easiest way to work. They take a little time to get use to but are extremely helpful. Krita works pretty well with most graphics tablets. The developers try hard to support various hardware and styluses. If you have used your stylus with other applications, Krita will probably work with it as well.

Setting Up Drivers and Configuration

One of the most common issues with tablets not working is related to drivers. In computers, drivers are how the graphics tablet talks with the computer. Make sure to download the latest drivers from the manufacturer’s website. This will solve a lot of the issues related to pens not working or not responding correctly.

Configuring Your Graphics Tablet Drivers

When you download the tablet drivers, it usually comes with software to configure it. Wacom tablets come with a program called Wacom Tablet Properties that you can find from searching the Start Menu on Windows. You can assign shortcuts to the tablet as well as modify the pressure sensitivity.

Wacom Intuos settings: This will look different depending on what type of tablet you own. You can customize shortcuts and pressure settings from the user interface.

The image above is a configuration screen for a Wacom tablet. The Mac and Linux versions should look similar. You can assign and configure the stylus to your heart’s content. I will explain a few common settings that you might want to customize.

• Tablet – Related to your drawing area. The options deal with using multiple monitors or resolving discrepancies between your monitor size and tablet size.
• Tool – Pen and external button options. Most of the configuration options will be done here with assigning shortcuts for your eraser, pen tip, touch strips, or other external buttons your tablet offers.
• Application – Every application works a little different, so you can specify different shortcut arrangements for each application.
  Make sure your tablet is plugged in before you start Krita. There are some situations where Krita won’t recognize your graphics tablet if your pen is plugged in later.

External Resources

The Learn section on krita.org has an abundance of educational videos and training material. The content ranges from DVDs and Wiki pages to videos. If a concept in the book is difficult to understand, there might be outside training. Most of it is free. You can also get in touch with the community for questions. You can press the F1 key while Krita is running to see the user guide.

Getting Help from the Community

While this book will cover most of the concepts with how Krita works, you will probably stumble on an area that might not be included. The feature might be new or something that has changed. There are three main areas that people go to when searching for help.

The Chat room is the fastest place to ask your questions. These can be related to installation issues, hardware issues, or building steps that might be hard to find. To access the chat room, you can go to the Krita website; there should be a link in the contact area on how to get connected or find the link on the Get Involved tab. Keep in mind that the chat room isn’t always going to get you an immediate answer. Many of the developers and volunteers may not be at their computer. If you do not get a response in a few minutes, you can take the next step.

The Forum can be a little better than the chat room since the conversations can be continued over days or weeks. You can search through the Krita forum and see if anyone else is experiencing the same issue. If you cannot find your solution, you can ask a question yourself in a new forum post. To access the forum, visit https://forum.kde.org. Click the Graphics & Multimedia area. Then click on the Krita forum. You can look at news, post your artwork to share, or visit the General Help topic.

The mailing list is a way to stay on top of Krita improvements via e-mail. There are two main types of mailing lists that exist: the mailing list on krita.org and the developer mailing list. The mailing list on krita.org is designed so you will be notified when new releases come out. If you don’t feel like checking the website to see if a new version has been released, the mailing list is a good place to sign up. You can sign up for this mailing list on Krita’s homepage. It usually includes information on what has changed and instructs you on how to download the new version.

The second mailing list, kimageshop, is designed for developers who want to be involved working on the application. At one point Krita was named “kimageshop”, so the mailing list has retained that name. You can talk with the developers in the chat room to find out if this is right for you.

Chapter 1 - User Interface

Knowing your way around an application always feels liberating. You can stop hunting around for what you want. The better you understand the interface, the more productive you can be. The Krita interface is flexible and powerful. You can change where things are located, update shortcuts, or hide areas that have little importance to you. There are even special modes where you can work entirely off shortcuts.

This chapter might go in more detail than you need to get started. If you feel like you have had enough, you can skip ahead to Chapter 2, where we go over painting. You can always come back if you want to learn more.

We will begin with creating a new document and navigating around the canvas. We will then start looking at how to customize all of the dockers and user interface (UI) elements. Other UI elements will slowly be introduced as we progress. By the end of this chapter, you will understand all of the UI concepts and features that Krita offers. You will also get a good idea of some common workflows that you can use.

Interface Basics

The interface is broken into functional areas. The blank area in the middle is called the canvas area. When you create or open a document, the canvas area will be filled with your working document.

Creating a New Document

When you launch Krita, most of the buttons and options will be disabled. You will need to have a document open for these tools to be available. To create a new document, go to the main menu and select File > New. Shortcut: Ctrl + N. A dialog will appear and give you options to choose from.

In the New dialog, the left panel has different options on how to start.

• Recent Documents – Open a previously opened document.
• Create from Clipboard – Create a new document based off what is stored in your clipboard data.
• Comic Template – Contains common templates for creating comics or manga.
• Design Templates – Contains film and web design templates.
• DSLR Templates – Contains common camera templates.
• Texture Templates – Contains templates used by texture artists.
  For now, go to the Custom Document type. Leave all of the settings alone. We can change these at any time. Click the Create button on the bottom right. You will see all of the buttons and menus on the application become enabled. Before we go deeper with all of the buttons, let’s learn how to move around the canvas.

Manipulating the Canvas

You will be moving around the canvas a lot while drawing and painting. It is nice to know all of the shortcuts to make this easier.

Panning – Hold down Spacebar. Your cursor will turn into a hand. Drag your pen around. This moves the canvas left, right, up, or down.

Rotating the canvas – Hold down Spacebar + Shift. Your cursor will turn into a rotate icon. Drag your pen around and see the canvas rotate. This is helpful if you are having a hard time drawing certain angles. As you rotate, notice how you receive feedback at the top left of your screen. If you want to reset the canvas to 0°, press 5 on the keyboard. The 4 and 6 keys will rotate the canvas in 15° increments.

Zoom in/out – Hold down Spacebar + Ctrl. Your cursor will turn into a magnifying glass. Drag your pen up and down. Your canvas will zoom in and out. To reset your canvas back to 100%, press 1.

Color selector – Hold down Ctrl. Your cursor will turn into an eye dropper. When you tap the pen on the canvas, the color that is underneath will be picked up for you to use.

Change brush size – It is required to have the Freehand Brush Tool activated for this functionality. If you hold down Shift + drag your pen left or right, your brush size will adjust until you lift your pen. While you can also change the brush size with the Size slider on the toolbar, it is much faster and convenient to use this shortcut.

In addition to the above shortcuts, there are also a few different modes and features that deal with working with the canvas and interface.

Canvas-Only Mode

Hide all of the user interface elements. Pressing the Tab key will toggle Canvas-Only mode. If you want, you can selectively show certain elements by going through the main menu Settings > Configure Krita > Canvas-only settings. By default, Canvas-Only mode will force your window to go full screen. If you want to keep Krita in a window, uncheck the Title bar option from the Canvas-only settings.

Full Screen Mode

Similar to Canvas-Only mode, but Full Screen Mode only hides your operating system controls. You can access this mode from the main menu View > Full Screen Mode. Shortcut: Ctrl + Shift + F.

Pseudo-Infinite Canvas

Quickly add more canvas to your document. If you move your document off the screen far enough, a new UI element will appear with an arrow. Clicking that arrow will add more canvas to the page.

Pop-up Palette

If you right-click on the canvas, the pop-up palette will appear. This palette is a quick way to select colors and change brushes. This can be helpful if you use only a handful of brushes. The different color swatches that are displayed on the ring are the recent colors that you have selected. Selecting a color will change your current foreground color.

Note

You must select a brush or click the canvas for the pop-up palette to disappear. If you start using the other tools or menus while it is open, the pop-up palette will remain on the screen.

Configuring the Pop-up Palette

The tag options icon on the Pop-up Palette allows you to configure which brushes will appear on the radial menu. Krita uses a tagging system to organize brushes. You can create your own tags to help you organize your brushes. By default, the palette shows the Favorites tag. When you create new tags, they will appear on the settings drop-down list. Selecting a different tag will replace the brushes with the ones you selected. Tags will be discussed in the Painting Fundamentals chapter.

You can also modify how many brushes will appear in the radial menu. By default, the pop-up palette shows 10 brushes. To change the number of presets shown, do the following:

2. Go to the main menu Settings > Configure Krita > General.
3. Locate the Favorite presets setting.
4. Change the number and clickOK.
   Keep in mind that the more brushes you show in the radial menu, the smaller the slices will be for each brush. The size of the pop-up palette does not change.

Dockers

Dockers can include color selectors, tools settings, brush presets, or other common tools needed for artwork. There are too many dockers to show on the screen, so Krita only shows a few at the start. These dockers can be moved, resized, hidden, or organized in a variety of ways. They will appear differently depending on how big your monitor is.

There are eight dockers here. Dockers can have their own space or be shown as a tab.

You can also make dockers float. Floating dockers will appear in front of the application. Moving the application window will not move a floating docker.

Dockers can be moved in a number of ways. You can dock something above, below, to the side, and even inside another docker. If you choose to place it inside, the interface will create a tabbing system where you can switch between different dockers. This is a good way to organize and clean up the user interface.

When you grab a docker by its header and drag your pen, the docker will tear off. If you go over existing dockers, you will get a preview rectangle showing where it will be placed.

In addition to the floating options on the header, there are a few other options to help you manage dockers. The icons are listed from left to right.

• Collapse (triangle icon)
• Lock Docker
• Float Docker (two squares)
• Remove Docker (X)
  Locking the docker will disable the movement for it. A docker can either be grouped with other dockers on a panel or be floating. When a docker is locked, all of the header options are either removed or hidden. This will ensure you don’t accidentally move something. You cannot lock a floating docker.

The Remove Docker icon will hide the docker from the application. If you want to show it again you can go to the main menu Settings > Dockers. Dockers remember where they were placed last, so turning a docker back on will place it in the last known spot.

Note

If you make a mess of the interface, or it gets in a corrupted state, selecting a workspace from the toolbar will reset everything.

Almost all UI elements are built with dockers in Krita. Mastering how to use dockers will help you customize Krita to the fullest.

Toolbox

When Krita creates a document, it selects the Freehand Brush Tool by default. If you aren’t sure what a tool is on the interface, you can hover over it and a tooltip will appear. The shortcut will also appear in the tooltip if it exists. Don’t worry about understanding what all of these tools do right now. We will visit these tools in greater detail throughout the book. You can resize the toolbox if you want to change how many columns are shown. This lets you change how many columns are displayed. You can also right-click inside the toolbox to change the icon size.

Tool Options

Most of the tools in the toolbox have additional options you can change. These options will all appear in the Tool Options docker. This docker might be hidden behind a tab when you first start Krita. It is often grouped with the Layers tab, depending on the workspace that is used.

Almost all of the tools have their own options. The amount of options varies for each tool. This example shows the options for the Crop Tool.

In the previous screenshot, you have the ability to constrain your cropping to a specific pixel amount, resize the crop rectangle based off the center, or constrain the proportions. Some of the options only have icons. You might have to hover over the icon if you can’t figure out what they are for. Some tools such as the Multibrush Tool contain a lot of options. If a tool doesn’t seem to be working correctly, make sure you take a look at the Tool Options.

The Toolbar

The toolbar is the top bar that spans horizontally across the interface. It has common operations that you may need to perform on a regular basis. You can also customize the toolbar by right-clicking the toolbar and clicking Configure Toolbars.

Document Options

Create, open, or save a document. There are common shortcuts to do these as well, but these icons can be useful if you are using Krita on a tablet.

Gradient and Pattern Selection and Editing

Create, edit, and manage a gradient or pattern. Your Fill and Gradient tools will use these options for filling.

Foreground and Background Colors

As you change your colors through the Color Selector Tool, Advanced Color Selector, or other means, this color will update. The bottom left black-and-white swatches will reset the colors to black and white. The top right arrows will swap your background and foreground colors.

Brush Settings Editor

Edit your current brush. This option might be disabled if you don’t have a brush tool selected. The brush editor is complex but powerful. We will be spending a lot of time customizing brushes in the Brush Editor and Brush Engines chapters.

Brush Presets

This contains all of the brush presets that are installed for Krita. You can also organize and manage your brushes through here.

Painting Blending Mode

This changes the blending mode while painting. Blending modes affect how your painting will interact with other layers. This is not linked to the blending mode on the layer.

Eraser Mode

Switch between painting and erasing. If you look at the toolbox, you will notice that there is no eraser tool. The Eraser mode tool concept is the primary way to erase things in Krita. When you toggle this feature, the blending mode will switch between Erase and Normal. Shortcut: E.

Preserve Alpha

Lock what areas can be painted on. When enabled, the transparent part of your layer cannot be painted on. This is useful as a masking technique. This is a separate setting than the layer’s alpha lock.

Reload Original Preset

Reset any changes that have been done to the brush. This ties into a concept discussed later called Dirty Presets.

Note

Right-clicking on a docker title will give you a list of dockers to show or hide. This is quicker than going through the main menu. Locked dockers cannot be shown or hidden.

Brush Opacity

Determine how transparent your brush stroke will be. A value of one is opaque, and a value of zero is transparent.

Brush Size

Change your brush size. Shortcut: Shift + left-click, then drag left or right.

Flow

There is another slider on the toolbar, but it is hidden. If you look at the two sliders, you will notice a drop-down arrow. If you click it, a menu will appear that will allow you to select a third option, the Flow setting.

Change what is shown on the slider slot. The add button (+) will replace what currently exists.

Flow is often confused with opacity since it will give similar results. The biggest difference is that flow controls transparency of each dab from the brush. Opacity controls the transparency with the entire stroke. In the following example, you can see that reducing the flow creates a softer edge. This effect is similar to having a marker that is low on ink. The marker still writes but has less ink coming out. The lines also build and interact with each other differently.

Mirror X and Y

The symmetry buttons allow you to create mirrored drawings or paintings. You can move the axis center by dragging the circle icon on the axis. The angles must be perfectly horizontal or vertical. You will need to use the Multibrush Tool for angled mirroring.

Workspace Chooser

Workspaces are predefined user interface layouts. Workspaces will save which dockers are open and where they are located. Selecting a workspace from the toolbar will apply the workspace. If you create a setup that you like and want Krita to remember it, you can open the workspace drop-down menu. At the bottom, there is an option to enter a name and save it.

Tip

You can right-click on any slider to input your own numbers. For example, if you want your brush size to be exactly 83 px, you can rightclick the Size slider. The input will turn to a textbox where you can enter your values. When you are done, click the Enter key. All number sliders work this way in the application.

Working with Multiple Documents

There are a couple of ways to work when you have more than one document open. One way is to have a tabs interface. This is the default document mode. This is easier if you need to quickly see what you have open. You can also discard documents quickly.

The other display type is subwindows. This allows you to view multiple documents at the same time. You can have the same document open with different zoom settings like the following image.

Artwork by David Revoy

Subwindow mode allows you to see the same document in multiple ways.

The shortcut Ctrl + Tab will switch to the next document. You can also press Ctrl + Shift + Tab to cycle backward through documents.

Changing the View Options for Multiple Documents

By default, Krita displays the tabs version for multiple documents. To change this, go through the main menu Settings > Configure Krita. On the General section, look at the Multiple Document Mode setting. When you change the setting and click OK, Krita will update its user interface to the new type.

Main Menu

The main menu is organized by function. Most features that exist in Krita are accessible via this main menu. Many of the common actions have keyboard shortcuts associated with them.

The menu system is almost never the fastest or most convenient way to do something. It gives you a rough table of contents of what the feature set of an application offers. You can see what exists and maybe what shortcuts are assigned.

Spend a few minutes if you want and look over all of the menu items. You will understand some menu items, while others will seem more obscure. Don’t worry about understanding everything right now. We will go over all of the menu actions by the end of the book.

Tip

Everything in the main menu can be assigned to a shortcut. Custom shortcuts will also appear in the main menu.

Status Bar

At the bottom of the application, you will see a few options in the status bar. These will help you see and manage your active document.

2. Selection display mode – When you create a selection, you will see a shape that shows what you have selected. By default, this selection is shown as an outline, known as the marching ants. The selection display mode is a toggle button that will switch the display from marching ants to a color-based mask display. When the mode is changed from ants to mask, the selection mask will turn into a color. The colors for the mask option can be changed in Krita’s configuration. The section on selections (Chapter 4) will go over this in more detail.

4. Current brush name – This area will originally be empty when you start Krita. As soon as you select a brush from the brush presets, this area will display the brush name.
5. Document information – This displays the document’s color model and color profile information.
6. Document dimensions – This displays the document’s pixel width and height. This will always be shown as pixels. After the dimensions, you will see a number in parentheses with how much memory Krita is consuming. This area is clickable to reveal more diagnostics. The Appendix has more information on memory management, if you are interested.
7. Zoom information – This is a visual indicator to set the zoom level for the document. If you click the drop-down arrow, you will get options to change it to one of the predefined levels. This drop-down box can also manually accept number inputs. You also have a slider to the right where you can drag your pen to change the zoom level.
8. Pixel aspect ratio (PAR) – This toggle button changes how the pixels are displayed on the screen. By default, pixels are square, but this is not always the case, depending on your document. This was more common when standard definition televisions were used. With modern technology, nonsquare pixels are increasingly rare. More than likely, you won’t have to worry about ever using this.

Themes

Krita comes installed with a few different color themes for the interface. By default, the interface uses the dark theme. Some artists prefer dark themes, while others prefer lighter themes.

Changing Themes

There are a number of predefined themes you can select. To change the default theme, go into the main menu and click Settings > Themes, then select a theme. As soon as you select the theme, the selected theme will be applied across the entire application.

Select from a few different color themes for the interface.

Configuring Shortcuts

The default shortcuts are nice, but you might want to change them. You might want to map a tool to your tablet, but it doesn’t have a shortcut assigned to it.

There are a lot of actions and functions that can be assigned or reassigned to a shortcut.

To access the shortcut configuration, navigate to Settings > Configure Shortcuts from the main menu. At the top of the shortcut window is a filter box. This is a live filter that can search names, actions, or shortcut keys.

Shortcut Options

There are two types of shortcuts you can assign: Shortcut and Alternate. To modify an existing action’s shortcut, select the cell that you are wanting to change. Clicking the Action name will autoselect the regular shortcut option.

When you select a shortcut name, you will get a couple of options.

• Default – This is the factory default. Selecting this will revert the shortcut back to the original shortcut.
• Custom – Assign your own shortcut. The small icon on the right will clear your custom selection.
  When you click the wrench button for the custom shortcut, you can press a key combination. In addition to numbers and letters, you can use the Shift, Alt, Ctrl, and the Meta (Windows/Apple) keys.

You can specify a shortcut to be a single button. You can also assign actions to multiple buttons. For example, you could assign the Freehand Brush Tool to be B, B. If you press B once, nothing will happen. If B is pressed twice in succession, the Freehand Brush Tool would be selected. One downfall with this is that you can only assign one shortcut to a key. This means you cannot have one shortcut as M and another shortcut as M, M. Setting M, M would erase the first shortcut.

You also must have a shortcut defined before you try to assign an alternate. If you try to assign an alternate shortcut without a primary one, the shortcut will be set as the primary shortcut.

Another interesting option with shortcuts is the ability to print out your shortcuts. The button says Print, but it is more of an export to a PDF.

Undo History

The Undo History keeps track of all of your changes and puts it in the Undo History docker. This docker is sometimes by the Layers docker in another tab.

Undo History docker shows all of the actions you have previously taken.

The Undo History can get you back to a specific state much faster than Ctrl + Z can. All you have to do is select which state you want to revert to. Your canvas will update accordingly.

Undo History rows have different states that can appear. You can see these paint strokes have been merged, called Cumulative Undo.

If you do a lot of painting, Krita might start to merge the brush strokes together. This is called Cumulative Undo/Redo. You can right-click in the docker to enable this setting. This feature is off by default. When it is on, there are a few options that will appear when you right-click in the Undo History docker.

• Start merging time – The same action will be merged if done for a given amount of seconds.
• Group time – Smaller times create more merges.
• Split Strokes – Controls the amount of actions needed before the docker will merge the actions into one.

Copy and Paste Options

You will frequently find yourself wanting to copy things from outside applications into Krita or copy things inside Krita itself. If you are working inside of Krita, this is done from the main menu Edit > Copy (Shortcut: Ctrl + C) and Edit > Paste (Shortcut: Ctrl + V.

Working Outside of Krita

If you are working outside of Krita, you can use the PrintScreen button (Windows) or Command + Shift + 4 (OS X) to copy your monitor display area to the clipboard. If using the Internet, you can right-click an image and select the Copy option. If you want to paste the clipboard data into a new image, from the main menu select Edit > Paste into New Image (Shortcut: Ctrl + Shift + N).

Cut Sharp and Copy Sharp

There are specialized versions of the cut and paste actions. By default, Krita will soften the edges of your cut and copy selections. The sharp options will remove the softening (anti-aliasing) to give crisp edges. These are accessed from the main menu Edit > Cut (sharp) and Edit > Copy (sharp).

Copy Merged

Take your selection and copy all of the layer contents. By default, Krita will only copy one layer. With Copy merged, the clipboard will copy everything that is visible in the selection. This is convenient when working with a lot of layers. Access from the main menu Edit > Copy merged.

Common Configuration Options

The previously discussed features are all you need to get started. There are some other nice settings that exist. The amount of configurable options could be an entire chapter, so I will only briefly discuss a few. I am going to go over some of the features that I think are the most useful. These options can all be accessed by using the main menu Settings > Configure Krita.

Undo Stack Size

How much do you like to undo your mistakes? By default, Krita will retain the last 30 actions that you have done. That means that your 31st action will not be reversible with an Edit > Undo. If you have a lot of memory (RAM) on your computer, you can probably increase this amount. It usually becomes more of a problem when you start working with large images since they tend to consume a lot of memory. This setting is located under the General tab under the Miscellaneous grouping.

Autosave

If you have made digital artwork in the past, you probably have lost your work from the application locking up or crashing. Autosave will occasionally save copies to prevent this. For large images, this operation can take a little while, so you might want to tweak it. By default, your document will be autosaved every 5 minutes. You can turn this off by unchecking the option. This setting is located under the General tab under the Miscellaneous grouping.

Brush Shape

When you are painting, you will get a preview for your cursor. This cursor shape can be changed. The Cursor shape and Outline shape will allow you to change the display. The brush outline will be the shape of the brush. This setting is located under the General tab under the Miscellaneous grouping.

Canvas-Only Settings

If you like working in Canvas-Only mode, you can decide which user interface elements you want to hide. By default, all elements are hidden. Many people don’t like to see elements like the status bar, so you may want to hide that. There is no option to hide the tabs area. If seeing the tabs really bothers you, switch to subwindows mode on the General tab to make them disappear. The other settings are all located under the Canvas-only settings tab.

Pasting Data from Simple Source

When you paste images from the clipboard, you may get a warning about how you want to paste the image in. You can automatically set which option to choose so you get no more warnings. This setting is located under the Color Management tab.

Artwork by Kynlo

<http://kynlo.deviantart.com>

Chapter 2 - Painting Fundamentals

Krita focuses on being a painting application above all else. It has a lot of image manipulation features, but that is not where it excels. If you picked up this book, you are more than likely some type of artist wanting to take your art skills to the next level.

This chapter goes over the painting system that Krita offers. We will first take a look at where all of the brushes are stored. There are multiple ways you can find and select brushes, depending on your workflow. There is even a tagging system to help organize your brushes.

The brushes that come installed are good but somewhat limited. We will look at how to find external brushes online to get more out of your painting experience. We will also learn how to load these files by using Krita’s resource manager.

In addition to painting, we will finish up with other helpful tools such as gradients, patterns, and resizing the canvas. This will give you the foundational knowledge to do all of the basics.

Preset Brushes

Krita comes preinstalled with a number of brushes. Other artists have created these default brushes throughout the years so you can start painting right away. These brushes are referred to as presets in some parts of the applications. They are occasionally called resources as well as paintoppresets.

Before you can start painting, make sure you have the Freehand Brush Tool selected.

Freehand Brush Tool (default tool) – Paint with the numerous brushes that are available from the Brush Presets docker. Shortcut: B.

Draw a few strokes on the canvas with your pen to see the results. The stroke should become more opaque the more pressure that is applied. If the stroke is a solid opaque color, that means your tablet isn’t set up correctly. Make sure you have your tablet drivers installed and configured.

By default, Krita uses the Basic_tip_default brush. While it looks okay, it doesn’t really have a lot of painterly qualities to it. We are going to pick another brush from the Brush Presets docker. Go to the brush presets icon in the top toolbar and take a look at what is available.

As you can see, Krita comes with a pretty good assortment of presets. The drop-down box right above the brushes is the tagging system. The tagging system allows you to pick your favorite brushes and assign them to a tag. You might have one tag for inking, another tag for sketching, and another tag for effects.

To the right of the tagging filter you will see a view options icon that controls how the presets are displayed.

• Thumbnails (default) – Show a grid of thumbnails with all of the brushes.
• Details – A list display of the brushes. You can see the name of the brush to the right.
  Change the way the brush presets are viewed.

While in Thumbnails mode, you can hover the pen over a preset thumbnail and it will reveal the brush name as a tooltip. The brush name is a nice hint, but you will need to test it out.

For now, select the basic_wet brush. Draw a few brush strokes with it and compare it to the previous brush we had. You will notice it feels softer and behaves a little differently. One of the biggest differences is the wet brush uses a different brush engine than the basic default brush. The basic brush uses the Pixel engine, while the wet brush is using the Color Smudge engine.

The Power of the Eraser

The way Krita does erasing is a bit different than other applications. While this might seem odd at first, it provides you with some excellent control. Instead of an eraser tool, there is an eraser toggle button in the toolbar. Shortcut: E.

Toggle quickly between painting and erasing.

The advantage of this toggle is that the eraser will inherit many of the brush properties. The eraser will be the same size as your current brush and will keep the same tip shape. This can make erasing feel more natural since it is a variation of your brush. If you change the size of the brush, the eraser will also change sizes. While you can change this behavior, it is nice for a default.

Toggling to erase mode will keep your brush tip the same.

When you erase an area, you are using a blending mode to do so. This blending mode, called Erase, is also available in the Layers docker. The default blending mode is Normal for a layer. You can change this via the drop-down at the top. This can serve a variety of purposes, including using it to mask out areas.

The erasing concept goes further. It can be used with many of the other tools. You can use the Gradient Tool to erase with gradients. You can erase using the shape tools like rectangles or circles. You can even erase using a pattern. There is so much flexibility with erasing, it can be painful to go back to other applications.

Tagging System

Organize and filter your tools by utilizing the tagging system. Tagging exists in different areas like gradients, patterns, and brushes. The most common area that people manage tags is the brushes. After playing around with most of the brushes, you will certainly have some that are your favorites. Instead of hunting those brushes down, why not tag them?

One way to manage and view your tags is in the brush presets editor. This is located in the toolbar on top and looks like a grid. You can also access all of the same icons using the Brush Presets docker.

Viewing presets and managing tags: This tag management is also visible on the Brush Presets docker.

The Brush Presets docker can be nice if you want to keep all of the brushes on the screen. When you open the Brush Presets docker, the drop-down will say “All”. This drop-down is asking you what brushes to display. By default, all presets are shown.

Click the drop-down and change it to Favorite Presets. You will notice the list of brushes shrinks. The drop-down is a tag list. If a brush is tagged with being a favorite, the brush will show up when you select favorites. How did those brushes get in the favorites? And how do you remove brushes from a tag?

Removing Brushes from Tags

We’ll start by removing one of the favorites from the favorite’s list. If you right-click on one of the brush’s thumbnail, a menu will appear.

The first item in the menu is the brush name. Even though it looks like it is clickable, it doesn’t do anything. The second option, Assign to tag, has a fly-out menu that shows all of the tags that exist and an option to create a new tag. The last option will remove the brush from the tag. Select Remove from this tag and watch the brush disappear from the Favorite Presets list.

Right-clicking on a brush will give you the tag options for it.

If we go back to the All option in the drop-down, we can then select a new brush that we want to add. If we liked the block_bristles brush, we could right-click the preset, hover over Assign to tag, and click the Favorite Presets option. If we would go back to see our favorite presets, the block_bristles brush would now appear.

Tip

All of the brushes are listed by name alphabetically. If you are having a hard time finding a brush, don’t forget about the search filter that exists at the bottom.

Using Tags with the Pop-up Palette

While learning the user interface, we went over the pop-up palette. You can use tags with the pop-up palette to change what brushes are shown. If you click the settings icon, you can select a tag from the list. Krita comes with quite a few tags. This is perfect if you like working in canvas-only mode without all of the dockers and user interface in the way.

Once you have selected a brush from the pop-up palette, the < and > keys will cycle through the presets. The one downside to these shortcuts is that the brushes will cycle alphabetically. It can be more difficult to switch if you have too many brushes assigned to a tag.

Adding and Removing Tags

We briefly covered the option to remove brushes from a tag, but we haven’t gone over how to add tags.

2. Click the plus icon next to the tag drop-down.
3. Enter a label for your tag where it says New tag.
4. Press Enter.
   After the tag is added, all you have to do is right-click any brush preset, select Assign to tag, and your new tag will appear on the list.

Create a new tag. You can also rename or delete the currently selected tag. Make sure to press Enter to apply the changes.

When you create a new tag, the presets will automatically change to your new tag. This is somewhat inconvenient since this list will always be empty. You will have to change the tag list back to All presets to be able to start adding.

This menu also contains options to rename the currently selected tag or remove it. Krita keeps a record of the last tag that you deleted. This means there will be an Undelete option available on the menu once a tag is deleted.

Importing Brushes

In addition to brushes that come with Krita, there are outside artists that provide brushes for you to use. Krita provides only a sampling to get started. New brushes are kind of like new toys. You get them and new worlds open up. Outside brush sets will include things that will help with rendering fire, foliage, or star fields. Let’s go over briefly how to find some brushes on the Internet and import them in.

Using Brushes from the Internet

Go to krita.org and navigate to the resources area. You can find this by going to the Learn section and clicking the Resources tab. You can see a number of different brush sets that artists have created.

Select the David Revoy brush set. This will take you to the GitHub site where David updates his brushes. GitHub is normally a site for programmers to share code. David decided to keep his brushes here since he updates them frequently. Let’s download them! You can see on the right there is a Download ZIP option at the bottom.

View the files and instructions to download David Revoy’s brush set. Use the download link on the right to get a zip file.

Tip

Sometimes brushes and textures are in formats such as a “tar” file. This is another format that is designed to make file packages smaller. If you are having issues opening any of the resources, take a look at the free program 7-zip at <http://www.7-zip.org/>.

Warning

Krita occasionally upgrades its brush system. These new features can make old brush packs break. When searching for brushes on the Internet, make sure to look for what version of Krita the brushes were designed for. Always try to download the latest brush sets to have the best chance of them working.

Open the zip file and select the two folders brushes and paintoppresets. We need to determine where to put these files so Krita will know how to load them. The easiest way to get to this location is from inside of Krita. From the main menu, go to Settings > Manage Resources.

This will open the resource manager. From here, click the option Open Resource Folder on the right. A new window will appear showing you where Krita is storing all of its brushes, patterns, and workspace information.

There should already be brushes and paintoppresets folders in there. Drag David’s brushes into these folders and save over them. On Linux, if you get the option to merge or replace, select merge.

That is it! The next time you start Krita, you will see the new presets in your presets areas. There are quite a few websites where you can find additional brush packs.

New brushes will appear after you restart Krita.

Importing Brushes with the Resource Manager

Another method for adding presets into Krita is through the resource manager. You can download resource bundle files from the Internet and import them into the resource manager. The file will have a .bundle file extension.

The resource manager allows you to manage brushes, patterns, workspaces, GIMP brushes, and Photoshop brushes.

To access the resource manager, go to Settings > Manage Resources.

Once you download a package from the Internet, you can import the bundle with the Import Bundle/Resource option. You can then choose what resources you want to be active. Active resources will show up on the preset editor, while inactive resources will be hidden. When you are done, press OK.

You can import individual images as well to use for patterns and brush tip shapes. You can see the full list of supported file types by clicking Import Bundle/Resource and looking through the supported file types in the drop-down.

Brush Smoothing and Dynamic Brush

When you are creating artwork, you might wish your brush strokes or inking would be smoother and more fluid. These are exactly what brush smoothing and the dynamic brush were created for. These will help take the shakiness out of your hand and allow you to draw more fluidly. There are two ways to accomplish this: the brush smoothing tool options on the Freehand Brush Tool, and the Dynamic Brush Tool.

Brush Smoothing

While using the Freehand Brush Tool, the first drop-down on the Tool Options docker lets you change the smoothing. This will help your brush strokes achieve a smoother result. By default, your brush strokes will not have any smoothing applied. Depending on what type of smoothing you have selected, you will be given additional options.

• No Smoothing (default) – The input from your pen will translate directly to the canvas without any processing. Drawing fast might result in slightly jagged lines.
• Basic Smoothing – This will smoothen out the jagged lines if you have a fast drawing style. I usually leave my brush on this.
• Weighted Smoothing – Similar to Basic Smoothing, but this option has extra parameters for working at different zoom levels.
• Stabilizer – Attempts to smooth your brush stroke by creating a buffer around your cursor (looks like a circle). Your brush stroke will only be applied when your stroke gets to the outside of the buffer.
  Options like Weighted Smoothing will give you additional options.

Dynamic Brush Tool

Reduce the shakiness of your brush strokes by adding mass and drag. This produces similar results as the Stabilizer option on the Freehand Brush Tool. Drawing things like spirals can give you nicer results. Set to low settings, you can even use this as a replacement for the default Freehand Brush Tool.

Dynamic Brush Tool – Creates smooth brush strokes by adding resistance and mass.

There is also a dynamic brush engine that exists in the brush editor. They share similar properties. The Dynamic Brush Tool has a few options for you to tweak.

Increasing the mass for the Dynamic Brush gives smoother results.

• Mass – Makes your brush strokes feel heavier. This will make your brush strokes move less across the canvas but will produce smoother results.
• Drag – Friction that will apply force in the opposite direction. High values will have little friction, while low values will seem like you are drawing with a rubber band.
• Fixed Angle – This is disabled at all times, so you can ignore it.

Fills, Gradients, and Patterns

Manually filling large areas can be tedious, so tools exist to help speed up this process. Enter fills, gradients, and patterns. If you don’t understand the settings, you can spend unneeded cleanup time. Let’s start with a basic fill tool in the toolbox and see what the options are.

Fill Tool – Take the selected area and fill it with the foreground color.

See the two circles on the left, followed by the same circles being filled with the Fill Tool. I changed the color with the color selector for the different levels of gray. I did three separate fills for the image on the right. There are a few tool options for the Fill Tool.

• Fast Mode – Ignores the selection when performing a fill. With the optimizations it provides, the fill will be done faster, with slightly less accuracy.
• Threshold – How similar does the color have to be to do the fill? Higher values will fill larger areas.
• Grow selection – Takes the base selection and expands it. This is useful for making sure line work is completely filled.
• Feathering radius – Determines how much to smoothen the edges of the selection.
• Fill entire selection – Fills everything inside a canvas. If there is no selection, fills the entire canvas.
• Limit to current layer – Only use the current layer’s pixel data to calculate where edges are.
• Use pattern – Use the selected pattern (seen in toolbar) to fill everything instead of the foreground color.
  When filling line work, the Grow selection option will be useful. Don’t forget about the Use pattern checkbox. It is easy to forget that patterns also use the Fill Tool.

Creating and Using Patterns

Let’s say we create a 256 px x 256 px image that we want to use as a pattern. After we have our image saved, the easiest way to load the pattern is to open up the Fill Patterns toolbar option near the top left. After the pattern is loaded, you can select it. Make sure the Use pattern option is selected on the Fill Tool, otherwise the Fill Tool will use the foreground color.

We can turn this repeatable image into a pattern.

Add your own pattern images by importing them.

One issue with the pattern editor is that you cannot scale or rotate the results. We cannot make the pattern smaller through any options. The only way is to save it as a smaller image size and import it back in again.

Here we have applied the pattern using the Fill Tool.

If we want to scale a pattern, there is a trick that uses layer styles. By applying a Pattern Overlay layer style, we have the option to scale. We will learn more about layer styles in the Adjustments, Filters, & Effects chapter.

Gradient Tool

The Gradient Tool fills your canvas with a combination of two or more colors. When you use this tool, you will be able to specify the starting and ending color ranges. The line you draw determines the distance between the beginning and ending values. Smaller lines will make tight transitions, while larger lines will be smoother.

Gradient Tool – Fills the area with the selected gradient. The Gradient Tool does not interact with what you have drawn on a layer. Limiting the effect will need a selection before applying the gradient. Shortcut: G.

Gradients applied: The right image has a circle selection to limit the effect.

The left image shows a gradient fill with no selection. Note that when using the tool, I drew a line going from left to right that spanned the entire canvas. On the right, I created a circular selection that included the one circle. Use the gradient editor on the toolbar to change colors.

Gradient Options

There are a few types of gradients to choose from. The Bilinear and Linear appear almost identical. The Radial gradient will produce a vignette-type effect. The most common types of gradients are usually the Linear and the Radial.

The Shaped gradient option has the most intelligence. It will create a gradient around the bounds of your selection. You can use complex shapes, and the gradient will gently move around the edge. This can be useful for creating a raised effect to give an object depth.

These examples use shaped gradients.

Creating Gradients

If you aren’t happy with the included gradients, create your own. The gradient editor is located on the toolbar. Once opened, click the Add icon. This will bring up a Custom Gradient editor.

From the gradient editor, you can edit the existing gradient colors as well as how the colors transition to each other. You can right-click the slider on the gradient to get additional options for removing, splitting, mirroring, or duplicating the segments.

Note

The Pattern Editing Tool exists in the toolbox, but it is only used for vector objects. There is no way to edit patterns once they are applied to a paint layer. This also goes for the gradient editing tool.

If you want to apply gradients and patterns more nondestructively, take a look at the Layer Styles section in the Adjustments, Filters, & Effects chapter. You can add a gradient or pattern layer style to your image. This will allow you to go back and edit them later.

Brush Dab vs. Brush Stroke

Brush strokes contain an entire motion of your brush. A brush dab is one brush sample. The spacing property will control how tight the brush dabs will be together. Increasing the spacing creates a large performance boost. If a specific brush is going slow, there is a good chance it has to do with the spacing.

Resizing the Image

Change the size of the image by growing or shrinking it. This will resize all of your layers, including the canvas. You can resize the image through the main menu. Go to Image > Scale Image To New Size.

In the dialog, the top area deals with the image in pixels. The bottom area deals with options for how the image will look when printed. Changing the pixel dimensions will automatically update the print dimensions. You will need to check the Adjust print size separately option to have different values. If you do not constrain the proportions when resizing the image, your image may look distorted.

Resizing the Canvas

Change the size of your canvas. This will only affect the dimensions of the document, not any of your layer content. This can be done from the main menu Image > Resize Canvas. You will be presented with a dialog where you can change the dimensions. The Offset area allows the canvas boundaries to move while the content stays in place. It is a similar effect to panning.

Changing the anchor point will help you decide what direction the canvas will grow or shrink. If you make the canvas larger and set the anchor point to the right arrow, the canvas will grow out in the left direction. If you set the anchor to the bottom, the canvas will grow in the up direction.

A second way to change the canvas size is through the pseudo-infinite canvas option that we learned about in the User Interface chapter.

Crop Tool

Resize your canvas dynamically on the screen. This can make your document smaller or larger. If you turn on the Grow checkbox in the Tool Options, the Crop Tool can resize the canvas to a larger size. The checkboxes by the width, height, and aspect ratio will lock the values. You can also change the appearance of the display by changing the Decoration. It can be set to common displays such as the rule of thirds (named Thirds).

Crop Tool – Resize your canvas. This includes expanding as well as shrinking. Shortcut: C.

When you are done setting the crop size press the Crop button or the Enter key to commit the changes.

Tip

When you are working with images outside of Krita, you can also drag and drop them right in the canvas. If there are no documents a new document will be created. If there is a document already open you will get two options: Insert as New Layer and Open in New Document. If you have multiple documents selected on your computer and drag them to the canvas, you will get additional options to add them all.

Trim Images

Trim images are special cropping methods that resize your canvas. These are located in the main menu under Image. Each option is used for slightly different purposes.

Trim to Image Size

Remove layer contents that fall outside of the image size. For example, if you import a large image that goes outside of the image bounds, it can slow your computer down. When you use the Trim to Image Size, all of the data outside of the canvas will be deleted.

Artwork by David Revoy

In the previous example, I imported some artwork on my canvas. You can see on the left image that the preview looks vertical. After the Trim to Image Size is done, the preview looks like the canvas size. This function trims all layers, not just the selected layer. This is usually done for performance reasons. In the example above, the image went from 36 MB to 14 MB.

Trim to Current Layer

Resize the canvas to the active layer’s content. This can be helpful in situations where you have multiple objects and want to export them separately.

Trim to Selection

Resize the canvas based off of your selection. The menu option becomes available when a selection exists. If you accidently create a selection instead of cropping, this feature can be a quick fix.

Artwork by Jose Conseco

http://joseconseco.deviantart.com

Chapter 3 - Layers

Drawing and painting in real life can be difficult. You might start with a pencil sketch, ink your lines, then add color over the top. This linear approach is nice because it is simple but difficult because it is inflexible and potentially destructive. If you need to go back and reference your pencil sketches, your lines might be covered with paint. If you painted a section with a color, it also might be difficult to change. These are the types of issues that layers can help with.

Layers are a way to organize all of the components of your artwork. One layer might have your rough sketches, while another layer might have your background. You could also have one layer with shadows and another with highlights. Layers are similar to painting on clear pieces of plastic. The separate pieces of plastic go over each other to build up the finished piece. The advantage is that you can modify one layer by itself without deleting or messing up other areas.

While layers are powerful, they are also dangerous. Too many layers can be a burden and slow down your computer. The more layers you have, the more time you will spend managing them. You spend more time organizing your layers and less time painting. Only you will be able to know where the balance is between what is helpful and what is a burden. Layers are all managed and organized through the Layers docker, so let’s start there.

Layers Docker

Layers are one of the most heavily used features in digital painting, so it will be shown by default when Krita starts. The following screenshot shows the basic areas of the Layers docker:

Right-clicking a layer will give you additional options and shortcuts for commonly used layer functions.

You normally start off with two layers when you create a new document. You can change the name of the layer by double-clicking the layer from the layer list. You can hover over a layer and see a larger preview for it. This will also show you other layer properties. I haven’t really found a use for this preview, but some artists like to see the thumbnail a little larger.

Note

Changing the blending mode or opacity can only be done with one layer at a time. If you have more than one layer selected, only the last layer will be affected.

If you look at your canvas, it will probably be white. This means the layer already has white “painted” on it. For this example, I deleted Layer 2, which has nothing on it. You can paint on the canvas layer and the results are what you expect. Now try to go to the eraser mode (E key) and start erasing. You will notice that the background turns into a gray and white checkerboard pattern. That isn’t the white background we had before. What happened?

Erasing an area from your canvas shows the transparency pattern underneath.

Tip

Use the Page Up and Page Down keys to quickly move up and down layers. If you are in Canvas-Only mode, you will get a notification with what layer you are on.

When Krita created the document, it filled the canvas layer with white. Layers do not usually start out with a color filled in. Most people are familiar with drawing on paper, so Krita fills the canvas layer to white for convenience. Having a layer that has nothing on it will be transparent. When we switched to the eraser, not only are we erasing the black strokes we made, but we are also deleting the white that Krita originally added. All of the color on the layer is removed. If there is no color to show, Krita will show the area as a white and gray checkerboard pattern, as we see in the previous example.

To get us back to a blank canvas, we are going to use a shortcut that fills the layer with the background color. Press the Backspace key. By default, the background color is set to white in Krita, so your layer will revert back to its original state. You can also repeatedly undo the last actions (Ctrl + Z) to get back to where you were. After you are back to your original state, rename the layer “Canvas”. You can rename the layer by double-clicking the layer name and entering your text.

If we want to draw and erase like we would expect, we need to create a new layer above the canvas layer. This allows us to paint and erase without deleting the canvas color. In the Layers docker, click the “+” icon. You will see a new layer appear in your layer list. You can rename this to “Painting” since we will be painting it. With this new layer selected, try to paint and erase like we did previously. You will notice that the white background remains, even as we are erasing. This is why Krita creates new documents with two layers.

Make sure layers are in the correct order. If you have your paint layer on the bottom and start to paint, it won’t look like anything is happening. Keep in mind that the “painting” layer has nothing in it originally, even though we still see the white background like before. We can test this by hiding the canvas. To hide a layer, click the eye icon right underneath it.

This idea of transparent areas will help us compose our painting elements together. It is pretty distracting to paint with a transparent pattern behind everything. Show the “Canvas” layer again by pressing the eye icon by it.

Show the painting layer while hiding the canvas layer.

There are more icons by each layer that are commonly used. You can toggle each of these icons on and off. Here is a brief overview of each icon.

Visibility – Show or hide the layer contents.

Lock – Disable moving or editing the layer. This will help you from accidently changing the layer when you don’t want to.

Alpha lock – When enabled you will not be able to paint on areas that are transparent for the selected layer.

Inherit alpha – Disables the alpha channel for the layer. This can be confusing to understand. We will go over this in more detail shortly.

Visibility

Show and hide the layer. You cannot move, delete, or manage your layer while it is hidden. Many of the layer actions are disabled while a layer is invisible. Interestingly, you can still change the blending mode and the opacity for an invisible layer.

There are even more options for each layer. Right-click on a layer to see what is available. Many of these options are also available from the main menu under Layer.

Lock Layer

When a layer is locked, its editing ability is frozen. You can still change the opacity, blending mode, and duplicate the layer for locked layers—but that is about it. A l ot of artists like to use this feature when they have a reference image that they don’t want to accidentally paint over. This will stop you from editing or moving the layer. In our previous example, it might be helpful to lock the “Canvas” layer. That way, you don’t have to worry about accidentally painting on it. This is quite useful when you are working fast and switching layers frequently. It is easy to forget which layer you are on.

Tip

To quickly change layers, you can hold down R and click on the canvas. The layer that contains the element under your cursor will be selected.

Alpha Lock

This is useful for staying in the lines with your art. You can paint a boundary for your character and enable the alpha lock icon. Now all of your painting, airbrushing, or other effects will stay inside that boundary. When you work close to the edges, or use brushes that have overspray like airbrushes, this is very useful. You can see the results in the figures below.

Tip

You can select more than one layer, but the only thing you can do with multiple layers is delete.

Inherit Alpha

This functionality is similar to the alpha lock. Inherit alpha will use all of the layers below the Inherit alpha–enabled layer to determine what can be painted on. An example might make this concept more clear.

Look at the following illustration. We have a canvas layer that we are hiding. We have a figure and an outfit layer that have a character design on them. The shading layer exists with Inherit alpha enabled. If we were to start painting on the shading layer, we would only be able to paint on areas that also are in the outfit and figure layer. Having the canvas layer invisible is important. If we were to make the canvas layer visible, the shading layer would paint on everything.

To explain it in a different way, look at your canvas. What areas have color on it? What areas are transparent? The areas that have color will be painted on. More technically, it merges all of the visible layers and uses it as a transparency mask.

The bottom three layers determine what can be painted on.

The only catch to this feature is that this mask effect only works on layers below the current layer. Look at the example above again. If we were to move the shading layer below the outfit, our painting would no longer use the outfit layer to paint on.

Opacity

Opacity controls how transparent a layer will be. This slider ranges from 0% to 100%. A few common uses for changing the opacity are listed below.

2. Painting under a sketch – It is common to create sketches before you start adding color. One common way to use opacity is to add your paint layer under your sketch layer. This way, you will be able to see your construction lines as you paint. As time goes on, though, your line work gets in the way. You want to only show a ghost of the lines. This is a great opportunity to reduce the opacity of your pencil layer. As your painting progresses and you add more detail, you can progressively make your pencil layer fade away.
3. Superimposing – Say you are combining multiple images. It is going to be difficult to do exact placement since your images will start getting in the way. If you reduce the opacity, you will be able to see through the image and more accurately place everything. When you use the Move Tool in Krita, it automatically does something similar.
   There are other ways that opacity is used, but those are the most common I have found. Most of the compositing techniques that are done use blending modes.

Blending Modes

Blending modes are selected from the first drop-down in the Layers docker. It doesn’t have a label, so it will be confusing for artists who aren’t familiar with it. This determines how the selected layer content will interact with the layers underneath it. If you are doing simple paintings, you probably won’t have to worry about this. There are some nice effects and workflow improvements that use blending modes. The blending modes are organized into different categories based off the algorithm that they use. The first category in the blending modes is your Favorites. Favorites can be managed by clicking the checkboxes to the left of each category. A few of the most common blending modes and their usages are as followed:

• Normal (default) – Your top painting color will replace color on lower layers. This is how you would expect color to work. Coloring over something replaces it.
• Multiply – Add darkness to the existing layer. Take the existing layer content and make it darker. If you paint with white on a layer set to Multiply, nothing will happen since white has no darkness values. People use Multiply layers to do things like add tattoos to their figures or add shadows. It is also common to make your pencil sketch layer set to Multiply. This will hide the white background and only show your pencil sketch.
• Screen – The opposite of the Multiply blending mode. Think of this as your lighten mode. Painting pure black on a layer with Screen will have no effect.
• Overlay – Combines the Multiply and Screen blending modes. This allows you to lighten and darken the image at the same time.
  Blending modes can get complicated. If you follow David Revoy on his YouTube channel, he has a helpful tutorial on explaining blending modes called Painting with Blending-modes.

Mark a blending mode as a favorite. This will add it to the Favorites category on the top grouping.

Note

Changing the blending mode doesn’t actually change any of the color information of the layer. It only changes how the color interacts with the layer around it.

Layer Actions

The bottom of the Layers docker has common operations that are performed. This is where you can manage your layers including adding, moving, and deleting layers. Let’s look at the operations, working from left to right.

Use these common actions to manage layers.

• Create layer – Clicking the “+” will create a new paint layer. Clicking the drop-down next to it will give you options to create other layer types.
• Duplicate – Make a copy of the selected layer. You can also Ctrl + drag a layer in the Layers docker to duplicate it.
• Move down – Moves the selected layer down in the order.
• Move up – Moves the selected layer up in the order.
• Move out of group – Requires a group layer. If the layer is in a group, this will move it out of the group.
• Move into group – Requires a group layer. If the layer is directly above or below a group layer, the layer will move inside the group layer.
• Properties – A way to change layer information. If using a filter layer, this allows you to change the filter applied.
• Delete – Removes the selected layer. You cannot delete a layer if it is marked as invisible. This includes masks and filters as well as painting layers.

Creating Layers

The add a layer option has a drop-down option next to it. If you click the plus icon, a new paint layer will be created. If you select the drop-down to the right of the plus icon, you will get options for additional layer types. Each layer type has a different icon that appears by the name.

In addition to layer types, there are also layer masks. Layer masks will look like they are nested inside your normal layer. These options will only affect the layer you currently have selected. These options are all nondestructive, meaning that you will not lose pixel information when applying them. You cannot add a layer mask to a layer mask. We will go over the different layer types in detail later.

Multiple masks have been added to a painting layer. Notice how they all appear nested.

Layer Groups

If you start using a lot of layers, you might want to group them into folders. Layer groups have many of the same properties as normal layers. If you are feeling risky, you can even nest group layers. You can also move layers in and out of groups by using the Move into and Move out of layer actions at the bottom of the Layers docker.

Tip

Layer groups have alpha locking and inherit alpha properties. Grouping multiple layers that share these settings can be helpful.

Clone Layers

Take an existing layer and create a reference of it. The following example will show how it works.

2. Create a quick drawing on a layer. I used the Multibrush Tool to create the mirrored effect.
3. Create a new Clone layer from the Add menu (use the drop-down menu to the right). The selected layer will be cloned. Move the layer with the Move Tool so it is not on top of the original layer. Notice the icon to the left of the layer name (highlighted in the image).
4. Select the original layer and paint a few more strokes. You will see that the cloned layer will also add those strokes. This can be nice for certain designs that need to be repeated.
   Note

The layer names are not descriptive when they are cloned. The name will say “Layer n”, depending on how many layers have been cloned. If you do end up working with a lot of clone layers, it might be a good idea to add them to a layer group to keep them together.

Filter Layers

Add effects or make adjustments to an image. Instead of applying a filter to a layer, you can create a filter as a layer. The advantage is that you can work nondestructively. If you think the image was sharpened a little too much, you can change the settings through the layer properties.

Fill Layers

Fill the entire canvas with a color or pattern. Like filter layers, you can alter this by going into the layer properties. This can create subtle washes or glazes over your painting. Glazing is a painting technique that will shift all of your colors to a specific hue, making your painting appear more cohesive.

File Layers

Some applications refer to this type of behavior as a “smart object”. You can reference an external image and modify it freely. The largest benefit to a file layer is that the image doesn’t degrade when the dimensions change. If you try to shrink a file layer down, you can then enlarge it back without any pixelation. Doing this to a normal paint layer will destroy the pixel information.

File layers are not embedded into the file. Do not delete the original image if you are using it with a file layer.

Note

Trying to do transformations like perspective or warping won’t work on a file layer. If you want to transform a file layer, you will need to add a transform mask first.

Mask Layer Types

A mask is a nondestructive tool that helps you remove unwanted areas. To understand how masks work, it is best to think of them like a selection. In a selection, every pixel is assigned a value from 0 to 255: white being transparent, black being opaque, and grayscale levels for everything in between. If you select white from a color docker, you can use Eraser mode to quickly add or remove from the mask. You can also press Delete to clear the entire selection. Here are the types of masks that you can use.

Transparency Masks

Determine which areas of a layer you want to show or hide. When you paint on a transparency mask, it appears like you are deleting the artwork.

In the following example, I added a transparency mask to a paint layer. Masks will appear as nested elements in the layer stack. The thumbnail besides the mask will tell you what the mask information is. I selected the mask and painted a few strokes. You can see the thumbnail change. Transparency masks are great for deleting areas that you might want to bring back later.

Filter Masks

Add a filter as a layer. The filter you pick can later be changed in the layer settings. The mask allows you to paint out areas that aren’t needed. The filter mask is a smarter version of a filter layer, so I always prefer to use this. There are effects in the Filter main menu called G’MIC that cannot be used for filter masks or filter layers.

Transform Masks

Distort and transform your layer nondestructively with a transform mask. Once you have the mask added and selected, you can use any of the transform tools. The visibility icon will toggle your effects. You have to use a transform mask when distorting file and clone layers.

Do transformations on a transformation layer mask (left). Toggle the changes off at any time (right).

Note

You can apply multiple masks to the same layer. If you want to apply a transparency mask, filter mask, and a transform mask all on the same layer, you can.

Local Selections

Take the current selection and assign it to a selected layer. When you have the layer selected, the local selection will become active. Changing to another layer will remove the local selection. You can hide the visibility of the selection by using the circle icon on the end. This is a convenient way to save a selection that is specific to a layer.

Some Other Nice Layer Options

Before we finish, I want to highlight a few features that are sometimes overlooked. All of the features can either be accessed through the right-click menu when you are on a layer or through the options in the Layer main menu.

Split Alpha

Split alpha takes the color information from the selected layer and creates a transparency mask. Splitting alpha is similar to the lock transparency feature. If you paint a few strokes and click the Split Alpha option, you will get a transparency mask of the area that you painted on. You can use this mask on the existing layer or move it to another layer that might need it.

Once you create a transparency mask with split alpha, the other two options will be enabled to Write as Alpha or Save Merged.

When you are done working with a transparency mask, you can use the Split Alpha > Write as Alpha option from the layer’s right-click menu. This will merge the mask back into the layer.

Merge Selected Layers

This option takes your selected layers and combines them. Combining layers will speed up the performance of Krita as well as making it easier to manage your layers. This option is only available with a shortcut. Shortcut:
Ctrl + Alt + E.

Isolate Layer

Hide all other layers in your document and only show the current layer. This will automatically be deactivated as soon as you select another layer. This can make it easy to spot transparency or masking issues. It can be accessed through the layer’s right-click menu. You can quickly do this by Alt + clicking a layer. You can also hide all other layers by Ctrl + clicking an eye icon. If you are isolating a layer, you might want to change the checkerboard pattern. You can do this from Settings > Configure Krita under the Display area.

Pass Through Mode

With Pass Through mode on, the effects of your layer groups carry through to lower layers. A common scenario is applying a filter layer. With Pass Through mode on, the filter layer will affect all layers underneath it. With Pass Through mode off, the filter layer will only affect layers in the layer group.

Layer groups will have an additional Pass Through option. This will apply blending modes and filter layer effects to layers below the layer group.

Another use is with layers inside of your layer group. If your bottom layer is set to Multiply, it normally would not affect the layer outside of the group. With Pass Through mode on, the multiply effect would be applied to the layer below.

Select Opaque

This option creates a selection based off the current layer’s contents. Krita will look at the alpha information to determine what to select. This is in the layer’s right-click menu as the last item. Select Opaque captures multiple levels of transparency. Your soft edges will be preserved if they exist.

Artwork by David Revoy

Here is the selection that is created when using Select Opaque. I turned the image off beneath so you can see the selection.

Flatten Layer

This option merges all of your masks for the layer together. Your masks will be applied to the normal layer and be removed. It can be accessed through the main menu Layers > Flatten Layer or from the layer’s right-click menu. Shortcut: Ctrl + Shift + E.

Tip

If the transparent checkerboard pattern isn’t working for you, you can change it to a color through the main menu Image > Image Background Color and Transparency. You can also change the checkerboard square sizes through the main menu Settings > Configure Krita in the Display section.

Merge with Layer Below

This takes the current layer and combines it with the layer below. Access it through the main menu Layer > Merge with Layer Below. Shortcut: Ctrl + E.

Compositions Docker

Save the visibility state of your layers. If you make changes to a composition, you can right-click the composition and select Update Composition. Double-clicking the composition will apply the composition. This docker is not visible by default. You will need to open this from the main menu Settings > Dockers > Compositions.

Compositions do not retain the layer’s position. You can also import and export compositions. You can rename a composition by right-clicking and selecting Rename Composition.

Turn layers on or off to save the arrangements in the Compositions docker.

Raghukamath

http://www.raghukamath.com

Chapter 4 - Selections & Transforms

Selections allow you to focus on certain portion of your image to work on. They are used extensively for things like resizing and masking out areas. The tools themselves are simple to learn. The real power with selections is knowing when to use them. As we go over the types of selections, we will see how they can speed up and enhance your creative workflow.

After we learn how to make selections, we will go over how to modify them. Transforms allow you to distort, twist, bend, and move your selections. With the combined forces of both, you will find yourself using these tools frequently. Selections are at the root of modifying your artwork, so we will start there.

There are three places in Krita that allow you to make selections: on the toolbox, in the main menu, and through the Layers docker. Some types of selections can only be done in certain areas, so we need to touch on all of them. Let’s start off by looking at the types of selection tools in the toolbox.

Toolbox Selection Tools

The most common selection tools are displayed in the toolbox. When you draw selections on the canvas, they will appear as a dotted shape, referred to as “marching ants”. Selections will always be closed when you are working on them. This means that the selection must loop back around and end in the same place it began. Here is a summary of the selection tools.

Rectangular Selection – Creates a rectangular selection. This is useful for quick selections that don’t need a lot of precision.

Elliptical Selection – Creates an elliptical selection. Holding down Shift will force the shape to be a circle. Shortcut: J.

Polygonal Selection – Creates a series of connecting lines to determine the selection shape. There are a few ways to close the selection:

• Double-click – Adds an additional line that connects back to your first selection point.
• Enter key – Adds an additional line that connects back to your first selection point.
• Closing the Selection – When you are creating a selection, you can hover over the first point. You will see a small circle appear. That is Krita’s way of telling you to close the selection. When you click, the selection will be closed.
  Many artists use the Polygonal Selection Tool for filling their line work. When going around a selection, you simply click in the places that will be close enough. Since you don’t have to worry about every motion of your hand, you can move fast and only put down points that you feel comfortable with. The final selection is behind line work, so the end results don’t need to be exact. If you currently use this tool, I would recommend checking out the Bézier Curve Selection Tool.

Outline Selection Tool – Draw an outline anywhere in the canvas to create a selection.

Contiguous Selection Tool – Only selects areas that have a similar color. If there is another disconnected area with the same color, it will not be selected. This is why the tool is called “Contiguous”. It has a few options.

• Fuzziness – The color you picked will have a greater range of values for the selection. Your selection will be larger with larger values.
• Grow/shrink selection – The selection will be expanded or shrunk after the initial selection is calculated.
• Feathering radius – Softens the edges of the selection.

• Limit to current layer – Only uses the selected layer to determine the selection. This option is disabled by default.
  Similar Color Selection Tool – Selects areas based off pixel information. This is useful for selecting areas that share similar color information. The areas do not have to be connected. There is one setting for this tool.

• Fuzziness – The color you picked will have a greater threshold of values for the selection. Your selection will be larger with larger values.
  Bézier Curve Selection Tool – Similar to the Polygonal Selection Tool. The main difference is that your points can be curved using Bézier points. This can be achieved if you drag your pen as you are clicking a point. The length of the handle will determine how much a line will curve in a direction. Once mastered, this tool is a superior version of the Polygonal Selection Tool.

The Bézier Curve Selection Tool will give better results than the Polygonal Selection Tool.

The Bézier Curve Selection Tool has more flexibility than the Polygonal Selection Tool. While this won’t save hours of time, it can make quick work with curved areas. For the previous illustration, I was blocking in the cat silhouette with the Bézier Curve Selection Tool. Blocking elements like this makes it easier to paint in the lines later. With the final mask, about 40% of the points were straight lines, while 60% were using Bézier points.

The tool options have no effect for the Bézier Curve Selection Tool. The biggest downside with working with selection tools is that you cannot edit your anchor point. You will have to convert the selection to a vector selection to edit the points.

Tip

Krita remembers the settings for your tools. After you configure a tool with the settings you like, you will not have to configure it again when Krita is relaunched.

Helpful Selection Shortcuts

Selections are a heavily used feature, so there are additional shortcuts available. When you are in the middle of creating a selection (while your pen is down), you can use the following shortcuts:

• Move the selection: Hold down Alt.
• Constrain the aspect ratio: Hold down Shift.

• Resize selection by its center: Hold down Ctrl.
  While seeing the selection is helpful, it can sometimes get in the way when you are more interested in the final results. Here are a few more shortcuts that help you manage your selections:

• Show/hide the selection:Ctrl + H.

• Select the entire canvas: Ctrl + A.
• Clear selection: Ctrl + Shift + A.

Selection Display Mode

By default, your selections are displayed as dotted lines, or marching ants, as they are often called. Another way to view your selection is the Mask display mode.

Selection Display mode: If there is no selection, the icon will be disabled. The current selection mode is Marching ants.

You can change the Display mode at the bottom left of the status bar. This button is enabled if you have a selection. When the Display mode is set to mask, the canvas will turn red and your selection will be cut out.

The Mask mode for a selection might seem like a somewhat useless feature at first, but it is quite helpful. When you have complex selections, it can be difficult to see everything. In the example above, you can see that the selection is over the line work. This makes the marching ants example difficult to see.

If a selected pixel is less than 50% opaque, it will not appear with the Marching ants display mode. The Marching ants mode can only show two states: selected or not selected. For this reason, the Mask display mode is superior in terms of information it provides. Mask display mode has the drawback of obscuring your artwork by covering almost everything with red. Most selections do not need a variety of opacity levels, so the marching ants will work fine for most things.

If you want to change the color, you can access this in the configuration. From the main menu, go to Settings > Configure Krita > Display. One of the options will be called Selection Overlay. Changing the slider on the right will control what opaque value will appear. If you want to make sure you can always see through the color slightly, make sure to lower the slider.

Update the Mask display color here. You can also select the opacity value that will be displayed.

Creating a Vignette Mask

Normally selections are either opaque or transparent. If your selection is filled with a color, it will create hard, jagged lines. Having a soft look will make your edges look more natural. A common framing technique for images is called a vignette. By using the Mask display type, we will see the selection better.

A vignette effect is used to direct a reader’s eye to the center of an image.

Making a vignette mask requires two steps:

2. Use the Elliptical Selection Tool to create a circle.
3. Use the feather selection option from the main menu Select > Feather Selection. Use 200 px for the radius.
   If you are in Marching ants mode, you won’t be able to see what the mask looks like. Turn your display mode to Mask to see the results.

Tip

Another helpful way to know you are hiding your selection is by looking at the mask display type. If you are hiding your selection, the icon will be filled with a checkerboard pattern.

Adding and Subtracting from Your Selection

When creating complex selections, you will quickly find yourself in a situation where you need to modify the selection. These are oftentimes referred to as “Boolean operations”. These actions take two selections and combine them in some way. Every selection tool comes equipped with these actions. These are the Tool Options from left to right.

Modify your selection with the different actions.

The Subtract action was used to remove part of the circle.

• Replace – Use your next selection as a new selection and remove all existing selection data.
• Intersect – Keep only the intersecting area between your new selection and existing selection. Shortcut: Hold down Shift + Alt before making a selection.
• Add – Add your next selection to the existing selection. Shortcut: Hold down Shift before making a selection.
• Subtract – Remove from the existing selection. Shortcut: Hold down Alt before making a selection.

Moving and Scaling Selections with Vector Selection Mode

By default, all of the selections you create are in Pixel mode. As you create and edit your selections, there is pixel data being modified behind the scenes. There is also a Vector mode that makes a vector selection. Vector selections can be moved and scaled without affecting the layer content. Vector and Pixel modes can be selected from the Tool Options with any selection tool. Let’s take a look at the differences of each mode.

Pixel mode (default) – Provides the ability to create selections by adding and removing using the actions (add, subtract, etc.). The disadvantage of this selection type is that it cannot be moved without moving up all of the layer contents.

Vector mode – Creates selections similar to the Pixel mode. Vector selections contain anchor points that you can edit. You can also move the selection around without picking up the existing layer content. You can only edit and move the selection, so the actions (add, subtract, etc.) are all disabled.

Moving a vector selection like a stamp: The blue outline that is created is a good indication that the selection is vector based.

When Vector mode is used when creating a selection, the Shape Handling Tool will appear in the toolbox. This will allow you to move and scale the selection.

As you can see in the example above, I reused the selection to serve as a stamp. After I was done moving the selection, I would switch to the Freehand Brush Tool, paint the selection, then switch to the Shape Handling Tool to move the selection. If you want to learn more about the Shape Handling Tool, take a look at the Vector Tools chapter.

An important thing to know with the Vector and Pixel modes is that you can convert a pixel selection to a vector selection. The best workflow I have found is to always start with a pixel selection. Most of the time this will be enough. If for some reason you need to move or scale the selection without affecting the layer, you can convert the selection to a layer mask by going to the main menu Select > Convert to Vector Selection. You can now use the Shape Handling Tool to move the selection around as I did previously. If you would need to continue editing the selection shape, you can use any of the selection tools as usual. As soon as you use a Pixel mode action, your selection will be turned back into a pixel selection.

You can also create a vector selection from a vector object. If you are on a vector layer and have a vector object selected, choose Select > Convert Shape to Vector Selection from the main menu. A new selection will be created that follows the outline of the vector shape.

Painting Selections with the Global Selection Mask

In addition to the normal selection tools, you can also paint a selection. This allows you to create selections with any of the painting tools. To accomplish this, we need to use the Global Selection Mask. Before we can start using it, we need to turn it on from the main menu Select > Show Global Selection Mask. A new layer will appear on top of your layer stack. If you have nothing selected, this layer will not appear. When you select your global selection mask layer, your color wheel will turn grayscale.

You can now paint on it as you would a normal painting layer. The effect is a bit delayed on your canvas when painting.

A new layer appears showing you the Global Selection Mask. The Freehand Brush Tool was used to create the selection.

Main Menu Selection Tools

While the toolbox contains the most commonly used selection tools, you will find the main menu contains a few gems. Many of these options need an existing selection before they can be used. Here is a summary of what the Select main menu options do:

• Select All – Discards any existing selections and changes the selection to fill your entire canvas. Shortcut: Ctrl + A.
• Deselect – Discards any existing selection. This is used frequently when you are done using a temporary selection and want to get rid of it. Shortcut: Ctrl + Shift + A.
• Invert Selection – Changes your selection to be the inverse of what it currently is.
• Reselect – Bring back the last selection you had. This is independent of the Undo stack, so you can perform operations and later regain your selection.
• Convert to Vector Selection– Change a pixel selection to a vector selection.
• Convert Shapes to Vector Selection – Vector objects will be turned into a selection. You will need a vector layer with vector objects for this to work.
• Convert to Shape – Takes your selection outline and creates a vector object out of it. The object is put on a new vector layer.
• Display Selection – Shows and hides the selection on the canvas.
• Show Global Selection Mask – Shows the current selection as a layer on the Layers docker. You can toggle the display by toggling the circle icon.
• Scale – Resize your selection numerically.
• Select from Color Range– Select a color on the canvas to use as a selection.
• Select Opaque – Make a selection based off all pixel information that has content. Only the active layer is used.
• Feather Selection – Soften edges for the selection.
• Grow Selection – Expand your selection to make it larger.
• Shrink Selection– Shrink your selection to make it smaller.
• Border Selection– Make a border around your selection. Specify how many pixels wide the border will be.
• Smooth – Quickly blur the edges of a selection to remove the aliasing.

Invert Selection Example

Reverse your current selection. Sometimes it is easier to select the areas you don’t want, then inverse the selection. For this example, we are going to paint a mountain range. We start with painting in the sky. We then invert the selection to paint in the mountains. The advantage of inverting the selection is we can add more details where the mountain meets the sky without having to worry about painting into it.

A quick sketch of the mountain is followed by making a selection for the sky area.

After a quick painting of the sky, invert the selection. The selection will be flipped to only include the mountains and landscape.

I also applied a feather to the selection with 5 px. This will help smooth the transition between the mountains and sky.

Paint in the mountains with the reversed selection. It is nice to paint the tops of mountains without have to worry about “bleeding” into the sky. The feathering creates softer lines.

Paint the mountains after feathering the selection.

If seeing the selection is distracting, you can hide it by pressing Ctrl + H. Don’t forget that your selections are hidden. This can be confusing when you need them later.

Tip

The Smooth selection option has no configuration. When you work with larger images, you will want control over the amount of smoothing, so I always prefer to use Feather Selection.

Transform and Move Tools

Take your selections and modify, distort, or alter them. If there is no selection, the transform will be applied to all of your layer contents. If you have a selection, the transforms will only apply to your selected area.

This is useful as it allows you to move areas, stretch objects, or otherwise modify an area that needs to be fixed. This can either be done directly on paint layers or done through transformation masks. The tool that will do all of the transforming is through the Transform Tool.

Transform Tool – When you activate the Transform Tool, handles will appear around your selection. The corner handles will allow you to scale the image. The side handles will extend or shorten the length of the sides. If you position your cursor slightly outside of the transformation box, the cursor will turn into a rotation icon. Shortcut: Ctrl + T.

Move Tool – Allows you to move multiple layers at the same time. There are a few tool options that allow you to pick what content to move. You can also move a layer with the Transform Tool. Shortcut: T.

There is a crosshair in the middle while you are transforming. In most applications, the anchor point is used for relative scaling. Dragging the handles will be relative to where the anchor is placed. This is not working correctly in Krita, so there is a good chance it won’t change your results when transforming.

Hold down Shift while dragging any handle. This will retain the aspect ratio of the selection. If you move your cursor inside of the selection, you can move the contents.

Transform Types

There are quite a few tool options for the Transform Tool. The top row presents different types of transform modes. Selecting one will present options that are specific to each transform type.

These transform type options are available with the Transform Tool. Only one mode can be selected at a time.

There are five types of transformations that you can do. They are listed from left to right:

Free – Simple operations include rotate, scale, and shear.

Perspective – Use handles to bend the image into perspective.

Warp – Subdivide selection to make changes.

Cage – Create a closed selection to make distortions.

Liquefy – Create distortions with different brush effects.

Free Transform

When you select the Transform Tool, it defaults to Free transform mode. While using the handles, you can move, rotate, scale, or shear the content. There are additional options available.

• Filter – Changes the scaling mode algorithm. See the explanation on the next page.
• Origin Position – Changes the anchor point with how the selection will transform and scale.
• Transform type – You can only do one type of transformation at a time. Select between Position, Rotate, Scale, or Shear.
• Transform type options – Each transform type has its own settings. Sliders are used for settings that have a limited value range.
  Tip

You can do multiple transformations before applying the changes. This means you can rotate the image then click the Scale option to do scaling.

A small explanation for the Filter setting. When doing operations like scaling, there is pixel information that needs to be created or destroyed. When you scale something up, there needs to be more pixels added to fill the space. Likewise, when you shrink something, pixels have to be removed. The Filter mode uses different mathematical calculations for determining how pixels are created or removed. If you change the filter setting, you will see the differences are usually minor.

Once you are done with your transformation, you can click Apply on the bottom of the Tool Options. Reset will reset all of the settings back to their original values. You can also click the Enter key to apply the changes. The Esc key will reset all transformations.

Perspective Transform

When you switch to the Perspective mode, it appears to be identical to the Free transform mode. The only thing that happens is that the handles will be updated on your canvas. Switch back and forth and you will see the side handles disappear on the Perspective transform.

Perspective transform will show you vanishing point indicators.

In Perspective mode, you can grab the handles to deform the object. As two points start to converge, a vanishing point circle will appear. Not only is it nice to see where the points converge, but you can also interact with the vanishing point circle. As you might guess, moving the circle will update the corner handles. You can also have two vanishing points: one point going vertically, and one point going horizontally.

You can do further transformations by switching types. This can make transformations difficult to manage, so I generally apply one at a time.

Warp Transform

Using the Warp transform is like turning your artwork into a piece of cloth. When you move or stretch part of the cloth, everything around it will bend and stretch. Everything will influence each other to some capacity. Like most settings, this is configurable.

Warping takes evenly spaced points that can be moved around. The zoomed in area on the right image shows the position indicators.

In the above image, you can see the Warp transformation in action. While transforming, the plus signs by each point are the starting positions. The circle for each position is the ending point. Using this mode is an easy way to play around with proportions.

The Tool Options look a bit confusing, but there are only a few things that really matter. These options are inside the Anchor Points group box.

• Subdivide – Create anchor points equally spaced. Setting 3 will create 9 points. Setting 4 will create 16 points. Setting this higher than 5 or 6 starts to make it difficult to work with. You might want the Draw option or Cage transform if you think you need this much control.
• Draw – Manually draw points on the canvas to create the anchor points.
  After you finish drawing points on the canvas, click the Lock Points button. Locking the points will allow you to drag the anchors and transform the content. If you find you need to modify the points, you can click the Unlock Points button. Keep in mind that unlocking the points will reset the transforms that you previously did. There is no way to remove one point. If you need to start deleting anchor points, you will need to click the Clear Points button, which resets everything.

The Anchor Strength property controls the formula for how the transformation points are interpolated. It is similar to how the Free transform has the Filter drop-down for scaling options. An option you probably won’t use much is the Flexibility property. This only has an effect if you have the anchor strength set to Strong (Rigid). Flexibility stretches the pixel information toward the anchors.

Tip

You can click outside of the anchor points to modify a transformation. If you are inside the selection, you can move the contents. If you are outside of the transform selection, you can rotate the layer.

Cage Transform

Similar to the Warp transform, this tool allows you to create anchor points on the layer. The biggest difference is that the points are more like a selection than arbitrary points that the Warp transform gives. When you are done adding points to your “cage” and want to start deforming, the points will create an outline connecting all of your points. You need at least 3 points to make a valid “cage” and start your deformations.

You do not have to “close” your points when you are done like when making selections. When you change to the Deform Layer option, the last point will automatically connect to the first point. Similar to the Warp transform, if you decide to add more points at a later time by going back to the Add/Edit Anchor Points option, your original deformations will be lost. Also, there is no good way to remove an anchor point from the Cage transform. If you need to remove any points, it is best to start over. The fastest way to remove all of your anchors and start over is by pressing the Esc key.

Creating anchor points around your object with the Cage transform can create natural deformations.

Only the areas inside of the cage will be affected. The stretched area will go outside the cage if you distort it enough. Like the other transforms, you can also move and rotate the entire selection.

As a last tip, you can select multiple anchor points when using the Warp and Cage transformations. If you hold down Ctrl, you are allowed to select multiple points. With multiple points selected, you can either move or rotate the points. There is a trick, though. If you try to select one of the points directly, only the last point will be moved. If you select inside of the cage and move it with the Move icon that appears, both of the points will be moved. Similarly, if you move your cursor outside of the selection and the Rotate icon appears, you are allowed to rotate the anchor points.

Liquefy Transform

While this tool is technically considered a transform, it will feel more like you are painting. There are five options you can use with the Liquefy mode.

Most of the Liquefy options will share the same settings. If a tool doesn’t support a certain property, it will be disabled.

• Move– Bends the painting with your brush stroke.
• Scale – Everything in the center of the brush will slowly move toward the outside. It creates a barrel distortion type of effect.
• Rotate – Rotate everything in the brush around the center point.
• Offset– Similar to the Move Tool. It is harder to use, though, since the direction will change depending on what direction your stroke is going.
• Undo – Undo any transformations that have already been applied.
  Original

Liquefy Move

Liquefy Scale

Liquefy Rotate

While doing the above example, the Reverse option was used quite a bit. This will swap out the way a Liquefy mode acts. For example, reversing the rotation will make the brush rotate the other direction. Reversing the scale will create a pincushion effect and make everything suck in like a black hole.

You can apply multiple Liquefy options in one pass. Do a little scaling and then apply some moving. Change to the Undo button if any of it doesn’t look right.

Build Mode

Choose between Build Up or Wash. This specifies how your brush stroke will act if it goes over an area again in the same brush stroke. Build Up will continue adding color in the same stroke. Wash mode will retain an even stroke.

Pressure Sensitivity Icons

On the right of the Size and Amount sliders, you will see pen nib icons. If you want to enable pressure sensitivity for these, you can toggle them on.

Show Decorations and Work Recursively

There are a couple of options on the bottom of the Transform Tool options. There is almost no reason to use these tools as they provide little value, but I will go over them in case you are curious.

Show Decorations – Shows the bounding box of the layer contents. This will be shown in a light gray, semitransparent box. This is enabled by default.

Work Recursively – This will apply the transforms to a group of layers or masks in a single pass. This is enabled by default.

Artwork by Banajune

<http://banajune.deviantart.com>

Chapter 5 - Drawing Assistants

Drawing everything with the Freehand Brush Tool can lead to great results. There are times, though, when using drawing aids can help you achieve difficult effects. Using an assistant is not cheating. Creating artwork fast is a trait that is important in commercial work. Assistants free you from worrying about creating perfect shapes like circles and squares. This is especially true in mechanical drawings.

Different assistants in Krita have different purposes. Some assistants, like the mirror mode, help your eyes stay fresh to catch errors. Other assistants, such as the Multibrush Tool and mirror mode, help you focus on automating mirroring functions. The important thing with drawing aids is knowing when they are useful. Some assistants are a simple button, while others need to be managed.

Horizontal Mirroring

As you spend more time working on a drawing, your eyes tend to lose perspective on things like proportions, symmetry, and placement. Depending on if you are right- or left-handed, your strokes will also have a natural tendency to lean toward one direction. It can be difficult to see mistakes unless you can see the image with “fresh eyes”. When is the last time that you drew an image only to come back days later to realize how incorrect it was?

To help you spot these types of errors, a common solution is to flip your image. To do this, all you need to do is press the M key. You will get a notification in the top left indicating whether horizontal mirroring is on.

It is best to use this aid early in your drawing process. I try to mirror my document every 10 to 20 minutes. Work in the mirrored state for a while so your eyes and mind get accustomed to it—then switch back. This is a great way to spot mistakes early before you get too involved with detail. I find this helps me keep my brush strokes straighter, as my lines tend to lean to the right.

Mirror X & Y

Quickly draw anything symmetrically. Many things in the world have a large amount of symmetry. These aids will automatically mirror your strokes across the x or y axis.

When a mirror toggle button is enabled, you are allowed to move the axis around by dragging it. The axis is always perfectly vertical or horizontal. You cannot rotate this tool. If you try to rotate the canvas, the axis lines will rotate along with it. You will need to use the Multibrush Tool to achieve that type of flexibility.

A common usage for the mirror mode are quick concept sketches. After I did each design on the left image, I moved the axis line over a bit. Perfect symmetry can look a bit dull and boring. If the design needs to show personality and character, make sure to go back and add some asymmetrical details to make it more appealing. The mirror mode can put you in this hypnosis where you do a lot of strokes randomly. Try to think of a direction you want to go before you start using it. It can be easy to spend a lot of time scribbling lines without anything coming out of it.

Measure Tool

Measure an angle on the canvas. Nothing is drawn on the canvas with this tool. It will inform you of an angle and tell you how long the line is. As soon as you switch to a painting tool, the angle assistant will disappear.

Measure Tool – Measures the length and angle between two points.

While you will not use this tool much, it can be useful at times. For instance, if you scan some artwork and it is crooked, you can use this tool to determine how many degrees it is off. Once you know the angle, you can go into the image properties and do a custom rotation to straighten it. You can only have one angle drawn at a time.

This can be used for finding a document bleed area or straightening scanned images.

Multibrush Tool

Create kaleidoscope and other mirror-type effects. This is great for coming up with unique patterns, textures, or symbols that would otherwise be difficult to generate. You will have to enable the Show Axes checkbox in the Tool Options to see the crosshair and guide lines.

Multibrush Tool – Use multiple instances of your brush at a time. Each stroke will be offset by a specific amount of degrees. Shortcut: Q.

Even though it shows a vertical and horizontal line by default, that doesn’t mean that the image will be split into four. You need to look at the Tool Options to determine how many slices the final result will give.

These are a few examples using the Multibrush Tool. You can use any type of brush preset with this tool. Symmetry is the default mode. It gives you a kaleidoscope effect. The options will allow you to move the axis, hide it, change the amount of slices, and rotate it. The available types of multibrush modes are as follows:

• Symmetry (default) – Divides the axis into multiple segments. The guides will only show you the vertical and horizontal axes though.
• Mirror – Accomplishes the same thing as the mirror tools on the toolbar with additional options.
• Translate – Gives your brush multiple tips that are spaced apart.
• Snowflake – Combines the mirror and symmetry options. This can give your end result a snowflake type of effect.
  This shows rotation of the axes with the Multibrush Tool. This cannot be achieved with the basic symmetry/mirror tools on the toolbar.

With all of these tools, you can show or hide the axes. They are usually helpful, but can occasionally get in the way.

The Mirror mode is a powerful option because you can rotate and move the axes where you want. Keep in mind that when you are working with the Multibrush Tool, you are still able to paint. It is common when starting out with this tool to set up your settings, then select the Freehand Brush Tool. Doing this will deactivate the Multibrush Tool and turn off your settings. Thankfully the tool remembers your settings, so reselecting the Multibrush Tool will get you back to where you left off.

The Translate mode will create multiple brush tips. This will create a bristle-type effect. In the following example, I simply changed the brush count. The placement of the different brushes will be the same every time, so there is no randomness applied to where each brush tip will be. Depending on what type of brush you have, this might slow down your computer.

Translate Mode for Multibrush Tool

The radius property will determine how much distance will be allowed between all of the different brush strokes. With a small radius, you will have a tight grouping. You can also change the brush size with the normal shortcut (Shift + pen drag), which will make each brush tip larger.

When you have the Multibrush Tool set to the Translate option, the mirroring options do nothing. The guides will still appear on your canvas but will have no effect.

Wrap-Around Mode

The goal of Wrap-around mode is to allow artists to create an image that is seamless when tiled. This is common in the movie and video game industry. Tiled textures are used on everything from grass and rocks to special effects. Let’s do an example of making a wallpaper background.

Let’s create a new document with 256 x 256 pixels. Wallpapers usually have some type of background color, so let’s add a dark color as a base. Change the color to a yellow and starting painting some design strokes for the pattern.

If 256 x 256 pixels is too large of a pattern when you turn on Wrap-around mode, reduce the image size.

That might work. Of course, it is really hard to tell what this will look like if it is tiled in both directions. Turn on Wrap-around mode to see the results. You can do this two ways. The fastest way is to press the W key. You can also access the wrap-around feature from the main menu View > Wrap Around Mode.

Wrap-around mode is now turned on for this same image.

Now that you see the design in its final form, it might need some tweaking. The areas don’t connect very well, and the overall pattern isn’t very cohesive. Let’s spend a little more in this mode and add more detail. You can also zoom out to see what the pattern will look like. Rotating the canvas (Space bar + Shift + drag your pen) also can give you a fresh perspective on what might appear more attractive.

Shrinking and rotating the image makes the pattern a little more dynamic.

The live preview of the tiling makes it easy to modify your image until you are satisfied. When you are done with the pattern, you can turn off Wrap-around mode. If you moved your canvas around while painting, you might have to find your original image. Turning off Wrap-around mode doesn’t return you to the original canvas position. Your image is ready to export without any further steps.

Tip

While in Wrap-around mode, you can rotate or scale the canvas as usual. If you scale too far out, your computer might become slow. Generating hundreds or thousands of tiles on the fly will do that.

If you press Ctrl + A, the original image will be selected. Wrap-around mode has many uses outside of wallpapers. Texture artists use this heavily and will want to take advantage of this feature.

Assistant Tool

The Assistant Tool contains the most powerful drawing aids in Krita. It contains assistants that will help you draw circles, lines, and vanishing points. They can be a bit difficult to figure out based on the name. We will start by going through each assistant individually, then later see how we can combine them.

Assistant Tool – Add, edit, and delete drawing assistants. The Tool Options give options for creating and deleting assistants.

• Vanishing Point – Your lines will converge at a single point.
• Ellipse – Creates circular shapes. The assistant snaps exactly to the circle.
• Spline – Creates a Bézier curve that your brush can follow.
• Perspective – Creates a grid that can be used to help with perspective. Your strokes will lock to the perspective.
• Concentric Ellipse – Similar to the Ellipse assistant, but you are not constrained to the ellipse path.
• Parallel Ruler – Draw a line and all lines will be constrained to that angle.
• Ruler – Your lines will be constrained to a line that you draw.
• Infinite Ruler – Your lines will be constrained to your assistant line. This extends beyond the start and end points.
• Fish Eye Point – Warp all of your lines along an axis. Using two of these assistants can create a fish-eye lens effect.

Managing and Using Assistants

Creating, editing, and deleting your assistants are all done through the Assistant Tool in the toolbox. Your Tool Options will update and show you the available types of assistants you can create.

Select Ellipse from the assistant type drop-down. You can now add three points to the canvas to create the guide. The first point you place will be one side of the ellipse, the second point will be outer side, and the third point will determine how elliptical the assistant will be.

After the Ellipse assistant is created, you will be able to do a few things. Moving any of the circles on the outside will squish and resize the shape. The middle cursor allows you to move the entire assistant. The delete icon removes the assistant. The eye icon will toggle the active status. Disabling the eye icon means that the assistant will not be used when drawing.

Now let’s see how to use the assistant. Let’s switch back to the Freehand Brush Tool. You will notice the ellipse assistant will still appear on the canvas. If you start drawing, the assistant doesn’t have any effect. This is because your brush needs to have the Assistant checkbox turned on. This is accessed from the Tool Options for the Freehand Brush Tool.

When you turn on the Assistant checkbox from the Tool Options, you will see a slider enabled on the right. This slider will determine how much influence the assistants will have on your brush stroke. High values will lock your brush to the assistants, while lower values will only apply your stroke as you get closer to the guide. It should start out at 1000. Let’s leave the setting there and try to draw something again.

Turn on the assistant from the Tool Options.

It works! After we draw a stroke or two, we are done with the assistant. We now want to move the assistant and resize it to make a smaller ellipse.

You can edit assistants by going back to the Assistant Tool. When we select the Assistant Tool from the toolbox, we will see the Ellipse assistant options come alive. We can now move the handles around and change the shape of the ellipse. When we are done, we can go back to the Freehand Brush Tool and start drawing. The Assistant Tool is designed to set up and manage your assistants. While most tools will apply things to your canvas, this tool will only help you set things up.

Showing and Hiding Assistants

If you want to disable a specific assistant, you will need to use the eye icon by it. This is shown on the lower right portion while you are editing assistants.

If you want to hide the visual guides for all of the assistants, you can do that in the main menu. The View menu has a couple of options to toggle the visibility.

• Show Painting Assistants – If enabled, hide all of the assistants while drawing. The assistants will still work, but you will not be able to see the guide lines.
• Show Assistant Previews – Show or hide the preview lines. These are not visible when editing the assistant. Only certain assistants use these like the vanishing point assistant.

Working with Multiple Assistants

Assistants are powerful because you can work with more than one at a time. Different assistants can be combined to create some helpful setups. Creating and using multiple assistants works the same as using only one. When you are adding assistants on the canvas with the Assistant Tool, you are in a create mode. Whatever assistant you have selected in the drop-down is what will be created. If you wish to later edit an assistant, you can click any of the controls that exist for each assistant. Create a few ellipses on the canvas like the following example.

Working with multiple assistants: Notice the two ellipses that overlap.

Snap single is a tool option that helps you work with multiple assistants. This option is on by default. If this option is off, your drawing strokes will be able to use more than one assistant in a single stroke as shown in the image below.

Having multiple assistants overlap creates issues when the Snap single option is off.

The two intersecting circles on the right are acting a little unpredictably. The magnetism slider of each assistant is what is giving us this effect. It is similar to how gravity pulls us in a direction. If we introduce another object that has gravity, it will try to pull us in a different direction. What direction we end up going in depends on how much gravity (magnetism) each assistant has and the direction of our brush stroke. This is a chaotic situation to be in while drawing. It is usually better to leave the Snap single option on to avoid this issue.

Now that we understand how to add, remove, and edit assistants, let’s continue to see what the other assistant types can do.

Ruler/Line Assistants

There are three line assistants that are similar, so I will group them together. You create these assistants the same way that you learned how to create the Ellipse assistant. Go to the Assistant Tool and see the different ruler options.

These assistants are all created the same way. You click a starting and ending point on the canvas. Even though they are created the same, you can see in the image above that they all behave differently.

• Parallel Ruler – Take your assistant line to set the angle for your brush strokes. All of your lines will be fixed at that angle.
• Ruler – Draw only in the area that is set by the start and end points.
• Infinite Ruler – Similar to the Ruler, but this will let your lines extend beyond the start and end points.
  Tip

Holding down Shift while moving an assistant point will snap the line horizontally or vertically. This works for all of the assistant types.

Spline Assistant

This assistant is similar to the Ruler assistant, but it has control over Bézier curve anchor points. From the Assistant Tool options, select Spline. The first two points you create on the canvas will be the start and end points; the last two points will be how the curve bends.

Your snapping is limited to the curve that exists. This can be helpful for larger curves that are difficult to draw manually.

Perspective Assistant

When you start off creating a Perspective assistant, you will be required to draw four anchor points. You will see an “x” appear when two of the corner anchors begin to converge. If you move the corner handles, you can reposition the grid. Like other assistants, you can delete, move, and hide the assistant with the associated icons.

If you grab any of the side handles, you will create a new perspective grid. This can be nice for things like walls. When you create connecting grids, the move icon will try to move all of the connecting grids along with it. When drawing on perspective grids, there are a few important things to know.

Extend the Perspective assistant to multiple planes. This can be done by grabbing any of the side handles on the assistant.

Tip

When you use multiple perspective grids, you do not have to worry about the different grids “fighting” each other with snapping. Whatever grid snaps first, your brush will stay on.

Lines will snap depending on where your stroke starts.

When using the perspective grids, you have to be careful where you draw. In the example above, the circles indicate where I started drawing.

2. I started drawing my line inside the grid right on a line. The perspective grid snaps like expected.
3. I started drawing my line in between grid lines. The perspective grid picked up fine and created a straight line.
4. If you start drawing outside of the grid, there will be no snapping, even if you later go inside the grid.
5. Trying to go a different direction now, my line still does not snap to the perspective grid because I started outside.
   You can see that the snapping for this assistant only works as long as you start inside the assistant. If you start your stroke outside the grid, the assistant will be ignored.

You do not have to use these assistants for snapping purposes. I have seen artists use the perspective grid only for reference. After creating a few grids, they simple draw on top with a regular brush. This might be able to help you visualize volumes better than staring at a blank canvas.

Vanishing Point Assistant

Have all of your brush strokes go toward a single point. This is similar to the perspective grid but allows you to make strokes outside of a grid. When you add a Vanishing Point assistant to the canvas, there will be multiple points shown like the image below. I added some numbers to the illustration to help explain what each point does for the assistant.

2. Assistant center – Move, delete, or disable the vanishing point. This also serves as the vanishing point that your lines will move toward.

4. Line guides – Handles that will rotate the guide line to where you want. This has no effect on the results. It is only an aid to help you line up things when using reference images or drawings.
5. Vanishing point guide – The vanishing point guide will move the vanishing point in relation to the line guide like a hinge. This can be helpful if your vanishing point is outside of the canvas.
6. Cursor line – This will draw a preview line from your cursor to the vanishing point. It is a preview of what will happen if you start to draw.
   If you hold down your pen in between the move icon and the eye icon, you can move the entire assistant with all handle guides. If you just move the assistant center, the handles will not move along with it.

Radial Speed Lines with a Vanishing Point

If you create one Vanishing Point assistant, you can get a radial speed lines effect. This is commonly used in comic books to create a sense of speed and motion. We can also create angular speed lines by using the Parallel Ruler assistant. These two assistants all by themselves are valuable.

Artwork by Ramón Miranda

Create a light aura using a Vanishing Point assistant.

Combining Assistants and a One-Point Perspective Setup

What makes assistants so flexible in Krita is that you can use more than one at a time. We will use this flexibility to create a one-point perspective setup. There is no button for this, so we will have to do a little thinking to accomplish this. We will need three assistants to make this work.

2. Depth – Vanishing Point assistant
3. Width – Parallel Ruler assistant
4. Height – Parallel Ruler assistant
   It doesn’t matter what order you create the assistants in. Let’s start off with the two parallel rulers. If you have any assistants still on the screen, you can remove them if you want by pressing the Delete all button on the assistant’s Tool Options.

Select the Assistant Tool and select the Parallel Ruler type. Create a vertical line and a horizontal line like the following example.

Create a one-point perspective setup with two Parallel Ruler assistants.

Notice that the bottom left part of the canvas is the edge of the document. I think it is easier to keep the assistants out of the way when drawing. If you have the Snap single option off and start to draw, you will notice all of your strokes will be constrained to either the horizontal or vertical line.

Lines may jump to another assistant if you get too close or change your stroke direction. This only happens when Snap single is unchecked.

All of our lines are constrained to the horizontal and vertical axis now. You will see a couple of diagonal lines that appear out of place. If you start drawing a horizontal line and move your pen vertically, there will be a catching point where the vertical assistant will take over. This is something to watch out for. It can actually create some interesting effects. Now let’s add our final Vanishing Point assistant.

Note

When using the Parallel Ruler assistant, the lengths of the lines do not matter. The angle is the only part of the assistant that has an effect.

Tip

When you get close to a vanishing point, there will be “jumping” between assistants. This can be minimized by drawing “to” the vanishing point. The farther you are from the vanishing point, the more predictable the lines will behave since the assistants will be farther apart.

In the following example, I moved my Vanishing Point assistant close to the other assistants. This serves as the horizon line, so you might want to move it so it aligns with your image. Now let’s try to go back to drawing something to see what type of results we come up with.

The final one-point perspective setup is in place.

While using the assistants can be nice for blocking in larger volumes, you will probably want to switch this off when doing detail work. You can manually click the Assistant checkbox to turn off the settings, or you can use the shortcut Ctrl + Shift + L. This shortcut can be a stretch for your fingers, so you might want to reassign it.

Creating a Two-Point Perspective Setup

Instead of going through the previous exercise again, we will jump right into the setup. This uses one-point perspective and adds an extra vanishing point.

2. Vanishing Point – Sets where the lines will converge. Notice how the assistant is aligned horizontally with the other vanishing point. The outside handles do not have to be lined up like the image.
3. Parallel Ruler – Sets the vertical angle. The position and length do not matter.
4. Vanishing Point – Sets where the lines will converge. The outside handles do not have to be lined up like the image.
   When you start working with multiple assistants, the assistant preview can get in your way. You can turn off these indicators through the main menu View > Show painting assistants and View > Show assistant previews.

To make a line and ignore all of the assistants, you can hold down the V key. This will temporarily activate the Line Tool. This can make it easier to get a line to respond correctly.

Tip

It is easy to forget where the vanishing points are at when you hide them. It can be easier to make a few small strokes by the vanishing points so you have a reference to go by.

Three-Point Perspective Setup

This is a similar setup to the two-point perspective. We are going to swap out the vertical parallel assistants with another Vanishing Point assistant.

The height will now converge to a vanishing point. You can move the height vanishing point farther away if you want the perspective distortion to be less severe. In the following example on the right, you can see a quick sketch using the assistants. As your view becomes farther away, the perspective effect diminishes.

Isometric View Setup

A popular style in video games and technical drawings, isometric artwork is similar to two-point perspective, but the depth will be parallel lines instead of using a vanishing point. This can be achieved by creating three Parallel Ruler assistants. The angle of the assistants is the only important part of the setup.

In the previous example on the right, I made a sketch, scanned it, then built up the foundation lines with the assistants. My original sketch angles were off, so the assistants helped correct them. After the foundation lines were in place, I turned the assistants off and drew over them on a new layer.

Fish Eye Point Assistant

Simulate a fish-eye, or telephoto, lens effect. The way these effects are generally done, you will need to create two Fish Eye Point assistants rotated 90 degrees apart.

On the left, you can see what a Fish Eye Point assistant will look like on the canvas. I also lightly drew in a few lines so you can see what will happen when you start drawing. The illustration on the right by Wolthera is taking this assistant as a base for helping her create this effect. Wolthera added more assistants to get this effect. She added an additional Fish Eye Point assistant that went horizontally. She also added three Vanishing Point assistants: one each on the left, middle, and right.

Artwork by Wolthera van Hövell tot Westerflier

Concentric Ellipse Assistant

Create circles at different diameters. This is similar to the Ellipse Tool, but the Concentric Ellipse assistant allows you to draw outside of the assistant line. When you start drawing, the brush will snap to that specific diameter. The only decisions you have to make are where to put the center and how circular the assistant will be.

Concentric circles can be useful from things like drawing tires to creating orbiting effects around objects.

Grid Tool

This tool shows a grid of guides on your canvas. The grid lines don’t have the ability to snap, so they can only be used for reference. To enable the grid, you can select the Grid Tool on the toolbox. Then press the Enter key. You can also turn the grid on and off from the main menu View > Show Grid option.

Grid Tool – Moves the grid.

There are no tool options for the Grid Tool. If you want to change how the grid is displayed, you will need to go into the preferences. Access this by the main menu Settings > Configure Krita > Grid. You can modify the display and settings from here. Changing the Offset property is the same as moving the grid with the Grid Tool. All of the numbers are in pixels. The Subdivision number will change how many blocks will be inside the main grid lines. If you select 4, there will be 16 blocks inside each grid block. If set to 3, there will be 9 blocks.

The grid can be helpful with alignment of elements like text. Graphic and web designers use them heavily to organize elements.

Rulers

See how large your image will be in different dimensions. Access the rulers from the main menu View > Show Rulers. Once activated, you can right-click on the ruler to change the units of measurement. This can be useful when working in print when you need to know where your margins and bleeds are going to happen.

The rulers include some useful, and not-so-useful, measurements. You cannot have a different unit of measurement for the horizontal and vertical rulers.

Artwork by David Revoy

<http://peppercarrot.com>

Chapter 6 - Adjustments, Filters, & Effects

After you spend some time building your art skills and get better with drawing volumes, colors, and shadows, you still might feel like something is missing. The proportions are correct, the lighting may be spot on, but it still seems a bit bland. It doesn’t have that “pow” that gives it energy. Filters and effects might be what you are looking for. If tastefully done, they can add a great deal of interest to an image. It can help the viewer focus on a specific aspect or create new energy.

Filters are used to make color adjustments and corrections to your image. Your image could possibly use more contrast. Maybe the colors are too saturated and they need to be toned down. These adjustments can be done to the entire image and can save you time from having to repaint.

There are a couple of different ways you can apply filters. You can add them destructively via the Filter menu or nondestructively via the Layer menu.

Let’s start with the tools needed for making adjustments. From there, we will go into more detail with effects. We will go into the mysterious G’MIC filters to see some of the unique features that they have to offer. We will finally go over how to create effects on text and artwork nondestructively using layer styles.

Common Adjustments

Color Adjustment Curve

Change the overall distribution of light and dark values. You might want to make the darks darker or the lights lighter. This increased contrast can make your artwork appear to stand out more.

For this example, let’s say that we like the overall image but want the highlights to be brighter and the shadows to be darker. Adding more contrast between the light and dark areas can force the depth more. This adjustment can be accessed through the main menu Filter > Adjust > Color Adjustment curves.

Artwork by David Revoy

You can modify individual channels to control the color.

The left side of the graph has the amount of black that is in the image. The right side of the graph has the amount of white. Everything between are the levels of gray. The diagonal line shown is the output. The line is diagonal because the values for light have a range from 0-255 (an 8-bit image). The value on the bottom left is mapped to 0, and the value on the top right is mapped to 255. You can see these mappings numerically by looking at the Input and Output numbers below the graph. Selecting different points on the graph will update the Input and Output values.

If we want the lights lighter and the darks darker, we will need to update the diagonal line to modify the color values. A common way to do this is to create an “S curve”.

You can see above why it is called an S curve. We added two points to the output line. You can do this by clicking inside of the white box. A point will be added wherever you click. You don’t have to click directly on the line. As you drag, the curve will be updated. To remove a point, you can either select a point (it will turn red) and press Delete, or drag a point so it is outside of the white box. The second way is faster since you don’t need to press any keys.

As you make your curve modifications, you will notice the canvas will show you a preview. Make sure the Preview checkbox is enabled to see the result. The effect is only applied to one layer, so your entire image might not be updated. If you want all of your layers to be altered, you will need to add a filter layer and place it on top of the layer stack.

Let’s go back to explaining the S curve. Bending the dark points down in the bottom of the “S” will allow the darks to be even darker. If you look closely, you will notice that the start of the left side is a few notches to the right. You can modify the points as needed like the image above. By moving the left bottom point over, you are making sure the darkest part of the image will be even darker by setting it as the new black. This is the same logic that is used for the whites.

If you are having a hard time grasping this, play around with the curve. It is one of those concepts that is better understood by doing. Watching your image update as you change values is the best way for this idea to sink in.

There were already a lot of light values in the image above, so you won’t see much change in that. You will see a noticeable change in the dark values. The image becomes slightly more 3-D looking as the shadows force the volumes of the house and landscape.

Like most adjustments, these changes are artistic decisions. Play around with the curves until you feel good about the final result.

Tip

A great way to see the change in an adjustment is to toggle the Preview option on and off.

If we want to use this filter nondestructively, we can use the Filter Mask in the Layers docker’s “+” drop-down. This will create a new filter mask to your layer with the applied changes. The Layers chapter has more information on filter masks.

Color Balancing

Color is great for setting the mood for your artwork. Saturated reds communicate a different mood than desaturated blues. While this play of colors can be subjective, it does add visual interest. It is common that after painting an image, you find that your shadows are a bit too similar in hue to your midtones. You would like to play around with the hues but don’t want to repaint the areas. You can use color balancing to pinpoint different light values and shift their colors accordingly.

For our example, say I want to add more color to separate the highlights and shadows. We will add more blue to the shadows to help them recede in the background. Then add a touch of red to the midtones to help them pop. Finally, add some yellow to the highlights to make the sun appear warmer. The color balance filter can be accessed from the main menu Filter > Adjust > Color Balance. Shortcut: Ctrl + B.

Color Balance options: You can modify the shadows, midtones, and highlight colors. The Create Filter Mask option will apply the effect nondestructively on a new layer.

The shadows are bolder and darker with the color balance change. Like the other adjustments, this is best to do on the fly. Make some edits and see what the result will be on the canvas. When you think you have a good balance, you can switch the Preview on and off to compare.

Hue/Saturation/Value

Another common adjustment is the hue/saturation/value (HSV). It can quickly desaturate everything in your image. It can also breathe life into your line work by adding a splash of color.

In the progression above, the illustration started as a value painting. The middle image added an HSV adjustment. If you are trying to add color to a gray image like the left example, you will need to check the Colorize option. If you do not, the saturation and hue properties will do nothing. By adding color, it can make organizing your other colors easier. The initial color helps dictate the final color palette, as seen on the right. Access through the main menu Filter > Adjust > HSV Adjustment. Shortcut: Ctrl + U.

Filters

Filters are classified as any image processing effects that happen to your layer. These effects range from blurring and sharpening to completely changing the style of your artwork. The adjustment examples we just went over are also considered filters.

Filters can be accessed two ways. The first is from the Filter main menu. All of the filters are organized by category. The second way to add a filter layer is from the Layer menu. All filters can be previewed on the canvas with a checkbox. It can be fun going through all of the filters.

Artwork by David Revoy

The Lens Blur filter softens the edges. The effect is applied with a filter mask. The mask allows the center to be removed from the effect.

Slow-Running Filters and Processes

Some filters can take a long time to process. If you applied a filter and it doesn’t look like it did anything, Krita might be in the middle of processing it. There are two places where this progress is shown. The first place is to the right of each layer on your Layers docker. The second place is on the status bar on the bottom right. This progress will appear for filters as well as other large operations such as resizing and moving content.

G’MIC Filters

G’MIC is a filter engine that specializes in image processing. It stands for “GreyC’s Magic for Image Computing” and is pronounced “gimmick”. It offers hundreds of filters and effects to enhance and modify your image. These filters and effects range from adjustments and special effects to patterns.

G’MIC comes bundled with Krita. To start using it, you will need a paint layer selected. This will make the G’MIC option enabled in the main menu. The engine can be accessed by going to Filter > G’MIC. A window will pop up with the available settings.

Unlike the other filters in Krita, you will not see a preview directly on the canvas. The Preview checkbox will update the Preview area as you make modifications. The Input and Output settings exist below the Preview thumbnail. These allow you to specify how the filter will be applied to your document. The available options are the following:

• Input – What layer(s) to use for the filter.
• Output – What layer(s) to apply the effect to on your document.
• Preview mode – What layer the results output to.
• Preview size – Where the preview will be displayed. If you pick On Canvas, your preview will appear on the canvas. Some of the effects are very computer intensive, so this can lock up Krita if you aren’t careful.
  The middle panel is a list of all of the effects organized into categories. The first category is only information. You can click the plus icon to reveal the individual effects. Below the effects list, there is an Update definitions button. Clicking it will connect to the Internet and update G’MIC to the newest version. If an update is done, you will need to close and reopen the G’MIC dialog to see the new filters. Below the Update definitions button is a Search text field, which will filter the list of effects seen. You can visit the G’MIC website to find out more with new releases and updates (http://gmic.eu/).

The right side of the window has all of the options for the selected effect. Some effects have only a few options, while others have a lot. If the settings are too big for the dialog, you can use the scroll bars to show more.

The bottom of the dialog has options to apply your G’MIC effects. These are listed from left to right:

• Reset – Resets all of the settings back to the default.
• OK – Applies your settings and closes the window.
• Maximize – Maximizes or restores the window.
• Cancel – Resets any changes you have made and closes out the window.
• Apply – Applies the effect to your image. The window will remain open. This is useful if you have multiple effects you want to add in a row.

Caveats

G’MIC filters cannot be used as filter masks or brush filters. The final result will always be destructive in nature. If you are adding an effect to a layer, you might want to apply the effect on a duplicated layer instead of the original. You can also use the Output setting in G’MIC to create a new layer with the results.

G’MIC is a newer feature to Krita so some of the filters are disabled. If an effect is disabled, it will still show in the menu. A dialog will appear letting you know that the feature has been disabled.

G’MIC Examples

You are encouraged to play around with the different effects that G’MIC has to offer. There are a lot of effects to try out, but you will probably only use a handful of them. Some effects can take a long time to process. A progress bar will appear, but it is deceptive. The numbers are not tied to the actual progress, so the numbers will often repeat. Here is a list of my favorite G’MIC filters I think have the most use along with the type of results they give.

Artwork by David Revoy

You might have to update your definitions on the G’MIC window to see all of these effects.

That should give you a good sampling of some of the G’MIC filters. Some filters need to be set up before they will work. For an example, see David Revoy’s article on G’MIC line-art colorization (<http://www.davidrevoy.com/article240/gmic-line-art-colorization>).

Layer Styles

Layer styles apply effects to a layer nondestructively. This is similar to applying effects with layer filter masks but with a couple of differences. First, you can apply multiple effects at a time with layer styles. Second, there is no masking ability with layer styles. They have to be applied to an entire layer. This feature is a carryover from Adobe Photoshop.

You can add a layer style by going through the main menu Layer > Layer Style. You can also access it by right-clicking a layer and clicking the Layer Style option.

When the Layer Styles dialog comes up, you are presented with a few options. The left side contains effects you can apply. If a setting is not checked, it means the effect will not do anything. As long as the Preview checkbox is enabled, you can see a live preview of the effects on the canvas. Press OK when you are done.

You can quickly create comic book or other interesting effects by adding layer styles.

Layer styles are frequently used to create text effects. In the example above, I drew text and applied Gradient and Stroke effects as the layer style. The effects are seen immediately as the styles are edited.

Don’t limit yourself to only using layer styles with text. Effects like gradients can add a lot of energy to your artwork. With the example above, I added a Gradient style to the shading. I also selected the Burn blending mode to blend the colors into the values. I could easily adjust the Gradient layer style if I wanted to shift the colors.

When you add a layer style, there will be an Fx icon that appears on the layer. You can toggle the effect on and off.

Tip

If you find bugs in Krita or have ideas, talk with the Krita community in the chat room or forum. The community is active, helpful, and can point you in the right direction.

Artwork by Alex Sabo

http://alexandrusabo.ro

Chapter 7 - Brush Editor Overview

One of the most powerful and unique features in Krita is its brush engines. There are so many options that it needs two chapters devoted to it. In the chapter on painting, we learned a little about how to manage the brushes and tags. We learned how to manage brushes, but we didn’t spend any time on how to modify or create them. The brush editor gives you fine control over how your brush works with your pen.

This chapter will go over how the brush editor is organized. We will go over the core components with the pen and shared brush settings. The next chapter on brush engines will go over the inner workings of each engine and explain the options in detail. With the combined knowledge of both chapters, you should feel comfortable with modifying and making your own brushes.

Like many of the other sections, this information will sink in better if you follow along. You can get a good overview by reading but will find it difficult to jump in and apply your knowledge without the hands-on experience.

Brush Editor User Interface

The brush editor is available from the top toolbar. Click the Edit brush settings icon to reveal the editor. The brush editor is organized into five areas.

2. Brush editor – Toggle the visibility of the brush editor from the toolbar.

4. Brush engine – Determines the type of behavior of the brush.
5. Preset strip – A list of brush presets that exist for the brush engine. Selecting one will change the preset editor values to match the preset.
6. Preset editor – Edit the settings that exist for each preset.
7. Scratchpad – A blank canvas to test out your brushes. The top dotted square is the area that is used for the preset thumbnail.
   The left side of the brush editor is where you select a brush engine. You can see there are quite a few engines to choose from. The preset strip along the top has all of the brushes that are currently installed for that brush engine. The left and right arrows will scroll through the presets if there are more of them.

If you change the brush engine at this point, the preset strip, settings, and setting details all change. All of the settings are tied to the brush engine. As you select presets, the selected brush name is shown below as well as the settings that define the preset.

Most of your time editing brushes will be in the preset editor. The settings on the preset editor are organized with attributes like General and Color. Each setting has its own setting details shown on the right. Selecting a setting on the left will update the setting details on the right. Most of the settings are optional.

Some settings like Spacing have a checkbox by them. When a checkbox is enabled, your brush stroke will start using that setting. If you modify the setting details but do not have the checkbox enabled, the effect will not be applied. If there is no checkbox by a setting like the Brush Tip, it means the setting is always used.

Every brush engine has a list of settings that are available. Some are common; others are unique to the engine.

There is a small lock icon that appears to the right of each setting. Double-clicking the icon will lock all of the setting details. To see this effect, select the Brush Tip setting, then change the presets by clicking through different thumbnails. You will see the setting details change every time you change to a different brush. Double-click the lock icon that is shown in the image below. Click through the different presets. The setting detail values will not change between presets. This can be helpful when wanting to keep the same settings across different brushes.

Lock setting across presets.

If a setting is locked and you right-click the lock icon, you will be presented with two ways to unlock the setting: restore settings from preset or keep current settings.

Right-clicking the icon gives options for unlocking the settings.

Scratchpad

On the right side of the brush editor, you will see an empty canvas area. This blank area is called the scratchpad. It is designed for you to experiment with your brushes. On the top area of the scratchpad, you will see a dotted rectangle, as seen in the image below. This area is called the preset thumbnail. If you modify a brush and want to save the new version, the preset thumbnail area is used for the thumbnail. If nothing is added, your brush preset will have a white thumbnail.

Preview thumbnail area: This is used when creating or editing brushes. This will be used as the thumbnail for the brush in the preset strip and Brush Presets docker.

The scratchpad has a few buttons on the bottom. The options, from left to right, are the following:

Fill preset area with current icon – Load the current preset icon and fill it into the preset thumbnail. If you are modifying a brush preset and want to keep the current thumbnail, make sure to click this before saving.

Fill area with gradient – Fill the scratchpad with the current gradient.

Fill area with background color – Fill the scratchpad with the current background color.

Reset area to white – Fill the scratchpad with white.

Global Settings

There are a few settings on the bottom of the brush editor that sometimes are overlooked. These settings exist on all brush engines.

* Default preset – Reset the brush settings to generic settings. This does not reset the preset to its previous values. You will usually want the Reload button instead.

• Temporarily Save Tweaks to Presets – Read explanation below.
• Eraser switch size – Eraser mode saves its own brush size. This can be useful when doing inking or line work.

Temporarily Save Tweaks to Presets

In general, when you make edits to a brush preset, they will be reset when you change brushes. If you change brush presets a lot, this can be inconvenient. You might only want your settings to be temporary, so you don’t want to save over the default brushes. This is sometimes referred to as dirty presets in the documentation.

When you click the Temporarily Save Tweaks to Presets checkbox, nothing happens. When you decide to start making changes to the preset by changing a property, like rotation, you will notice two things happen. First, the preset in the preset strip will add a pencil icon. Second, a Reload button will appear next to the brush name as the image below shows.

If you change to a different preset, you will notice the first preset will still have the pencil icon by it. When you return to the brush, your rotation value is still saved.

The Reload button will reset the preset to its original settings. If you start changing settings and you realize you messed stuff up, you can hit the Reload button to start over.

Brush Editor Context Menu Options

When you have the brush editor open, you can right-click over it and get a few options.

Right-clicking on the editor gives additional view options.

• Detach from Toolbar – Detaches the brush editor from the toolbar. This will make the editor a floating window you can move around. This option changes to Attach to Toolbar when floating.
• Show Preset Strip – Show or hide the brush presets that appear on the top.
• Show Scratchpad – Show or hide the scratchpad area on the right.

Shared and Unique Properties

A shared property is a setting in the brush editor that is available in multiple brush engines. Brush Tip, for example, is available on almost half of the brush engines.

These are the available settings for the Pixel brush engine. The Brush Tip setting appears in most of the brush engines.

Each setting functions the same across different brush engines. Learning how a setting works on one brush engine means knowing how it works on all of them. You can test this out by going to a few brush engines on the left like Color Smudge or Bristle. After playing around with the settings for a bit, you will notice that the sliders and knobs are identical between the engines.

Once you understand the concept of shared properties, it will make working with brushes easier. Some common shared properties are the following:

• Blending Mode – Change how your painting will interact with the layers below. This is tied to your brush. The blending modes that are used for layers are calculated separately.
• Opacity – The transparency your brush strokes will have.
• Flow – The transparency your brush dabs will have. If you don’t remember the difference between opacity and flow, refer back to the Painting Fundamentals chapter.
• Sharpness – Removes the smoothing of the brush. This is useful if you are creating pixel art.
• Hue – Shift the hue of the color. Hue identifies the name (red, blue, green).
• Spacing – Change the spacing between brush dabs. Setting the spacing too small may slow down your computer.
• Texture – Assign a pattern for each brush stroke.
  There are a lot of properties and settings to play around with. The best way to find out what a brush engine supports is to experiment. Referencing existing brushes is a good way to learn as well.

Pen Settings Overview

Many of the brush editor parameters have options to customize your pen settings. All tablets support different levels of control, so some settings might not work for your graphics tablet. Your pen might not support tilting or tangential pressure. If you are unsure of what your pen tablet supports, visit the manufacturer’s site.

The pressure curve exists for many of the brush engine settings. You can set a global curve by checking the Share curve across all settings checkbox.

Many of the setting details have a curve that you can change. This allows you to modify how your pen pressure will be used. The pen settings can be overwhelming to look at, so let’s take a look at a couple of the settings. Go to an Air-brush pressure preset from the Pixel engine. Then go to the Opacity setting. Before we do anything, draw a few strokes on the scratchpad to see how the brush currently behaves. Make sure to use your pen to get varying results.

Every pen setting has a different curve to adjust your pressure. While this allows a great amount of freedom, it can be tedious to have to set each one. If you have a curve that you want to apply to all settings, check the Share curve across all settings checkbox. When checked, there will be only one curve to control them all.

You can see in the above image that the harder you press, the more paint is applied. The paint is directly related to how hard you are pressing. Now let’s go back to the brush editor and click on the Enable Pen Settings option under the Opacity setting. This will uncheck the box and disable all of the pen controls. Make a few strokes and see what we have done.

Our brush size is still being affected by the pen, but the brush opacity is always opaque. Disabling the setting doesn’t turn the pen pressure off for everything—just opacity. Before we turn the Enable Pen setting checkbox back on, let’s do one more thing. Above the pen settings is an Opacity setting. Change the opacity to 0.25 (25%) and try to paint again. The brush strokes will now be lighter than they were before.

There is no pen pressure, so your strokes will apply an even 25% opacity. If you paint over the lines, you will see that the colors start building on each other.

While this was a good learning exercise, I doubt you would want to keep these settings for your everyday painting. To reset your settings, click the Default preset button at the bottom of the brush editor. You can also select another preset and come back to reset the settings. Click through different settings in the Pixel brush engine to see how common this pen pressure setting is.

That takes care of the pen settings overview. Now let’s take a look at each pen capability to see how they will affect our stroke. Remember that your pen might not support these settings, so don’t curse your computer and throw it out the window if a setting is having no effect.

Pen Capabilities

We just looked at the pen pressure settings. As you saw, there are a lot more. Let’s spend a little bit of time going over all of the capabilities, or sensors, that a pen might have. Each pen setting has a curve associated with it. You will notice that some of the settings have different labels. A brief illustration is included in case you aren’t sure what type of motion is involved.

Pressure

Your pen keeps track of how hard you press the pen. Most tablets support this feature but not all. Some budget tablets are not designed for artists, so they may not mention this feature when you buy it.

PressureIn

This is similar to pressure. While pressure values can get larger and smaller with each brush stroke, pressureIn values can only get larger.

X-Tilt

X-tilt is the angle that is created between your pen and graphics tablet in the x axis. It ranges from -30° (left position) to 30° (right position).

Y-Tilt

Y-tilt is the angle that is created between your pen and graphics tablet in the y axis. It ranges from -30° to 30°. The maximum effect happens at 0°.

Tilt Direction

Tilt direction is the angle between your pen and your graphics tablet. Pointing your pen forward is 0°; pointing to the right is 90°. The maximum effect will happen at 359°.

Tilt Elevation

The angle that you hold your pen at determines the value. Perfectly straight up is 0°. Full effect would be at 90°, but this is pretty much impossible as your pen would be laying on its side. You will have to adjust the curve for the pen to be something more realistic. It does not matter what direction your pen is facing (north, south, east, west).

Drawing Angle (Software)

The effect changes based on the direction you are drawing. You can see that a horizontal line has no effect. No effect is produced from applying a 359° angle, while the full effect is produced from a 1° angle. It is a continuous calculation as seen by the circle drawn inside.

Fan Corners

The Drawing angle sensor comes with a Fan Corners checkbox. The examples to the left show a couple of strokes with sharp turns. In the first brush stroke, Fan Corners was off. When enabled, your brush strokes fill the gaps.

Rotation

Rotation is achieved by twisting the stylus. This is not supported by many tablets. You will see this available in more specialized pens such as the Wacom 6D art stylus. The values range from 0° to 360°.

Speed (Software)

The speed at which you make your pen strokes will change the value. Faster pen strokes will give you higher values on the curve.

Distance (Software)

The value reduces the further your brush stroke goes. This simulates a pen that has an ink well. The effect will change over a given amount of pixels—specified in the Length property. The example below shows what happens when the Repeat checkbox is enabled. This causes the stroke to start over whenever the ink runs out.

Time (Software)

Think of this as a countdown to when your brush will stop applying a stroke. If you set the duration to 3 seconds, the effect will diminish as the countdown approaches 0. Once the countdown is reached, the effect will not be applied. The only exception is if you have the Repeat checkbox on. This will reset the timer after it reaches 0 and start the effect again.

The value is slowly decreasing based on time.

Fuzzy (Software)

This adds a degree of randomness to the brush stroke. For the example below, I added some fuzziness to the opacity setting. The first stroke has no fuzziness. The second example has fuzziness. You can only control this effect by the curve.

Fade (Software)

The value changes based on the rate that paint dabs come out (individual brush blots). The effect is similar to the Distance sensor. The Distance sensor changes based on the distance you move the brush stroke. Changing the spacing on the brush will make the Fade effect more apparent on the edge of the brush tip.

Perspective (Software)

Your strokes will change as they get closer to the vanishing point. It takes effect when you are working with the Assistant Tool. This does not work with the Perspective Grid Tool. This effect is independent for each perspective grid.

In the above example, I had a tree brush that I checked the Perspective option on the Size setting. My brush strokes automatically scaled down as the brush got closer to the vanishing point line. This takes away all of the guesswork with sizing. When working with this, you have to be careful to stay inside the grid. If your stroke goes outside of the grid, the perspective sensor will be ignored. This will cause some unexpected results.

Tangential Pressure

This is used with an airbrush stylus. It is usually the finger wheel that is attached to the top of the stylus. The values range from negative one to positive one. Zero is the neutral position. This is sometimes referred to as barrel pressure. Do a search for the Wacom Intuos airbrush if you are curious.

Note

Your pen will probably not support all of the technologies that Krita can handle. The best way to test this is to enable one of the settings and make a few strokes on the scratchpad. You must have one pen setting enabled at all times. You will have to disable the Pressure setting to individually experiment with others.

Sharing Custom Brush Presets

Krita allows you to share brushes that you have created. Brushes use a native format called KPP. This format saves the preset thumbnail as well as all of the settings. When you save new brushes, they will be added to your paintoppresets folder on your computer. The easiest way to get to this location is through the resource manager. This is accessed through the main menu Settings > Manage Resources. Click the Open Resource Folder button and navigate to the paintoppresets folder.

If you have created any brush tips, those will be located in the brushes folder in the same location. When people share their brushes, they usually compress (zip) their brushes and paintoppresets folder. Of course they only include their new files and not the default presets.

Manage brushes and assets through the resource manager. You can also activate bundles that you want to use. Inactive bundles will not appear in the application.

An alternate way to share your files is to use the resource manager. You can click the Create Bundle button and start adding brushes, pattern, presets, and more. When creating a bundle, the area on the left adds meta data for things like the name and description. Everything will be saved to the bundles folder in the resource folder.

Bundle files are just compressed zip files. If you download a bundle and it isn’t working for some reason, you can manually extract the brush and preset files out to your resource folder. You might have to rename the extension to .zip for your compression program to recognize it.

Artwork by Evgeniy Krivoshekov

<http://schekobon.deviantart.com>

Chapter 8 - Brush Engines

While we went over some of the general settings for the brush editor in the previous chapter, we didn’t really spend much time digging deep into each brush engine. If you start reading this chapter and get confused how to find something in the brush editor, make sure to study the Brush Editor Overview chapter. That provides a good foundation on how the brush editor is organized and functions.

There are a lot of powerful brushes that come with Krita—and even more brushes that you can find elsewhere. If you cannot find a brush that you are looking for, or want to make some tweaks to an existing brush, you need to learn more about the brush engine.

Each brush engine has its own behavior. Some engines are easier to understand like the Shape engine, while others take more explaining like the Pixel engine. We will look at each brush engine one by one to see what they can do. This chapter is not exhaustive on the brush engines. An entire book could be written on this area.

For each section, we are going to see some examples of the brushes in action. We can then dig a bit deeper and see what makes each engine unique. As we slowly peel away the properties, you will see that they aren’t as scary as they might look.

Pixel Engine

This is a good brush engine to begin with since it is similar to other painting applications. With brush editors in other applications, you generally start out choosing a brush tip. This might be a leaf shape, a rock texture, or a simple circle. From there, you start to add settings such as opacity, scattering, or rotation. This is a similar process to how the Pixel engine works in Krita.

The Pixel engine gives you the most options when creating a brush. This is why you find so many brush presets that use this brush engine.

To avoid being redundant, we will go over many of the settings only once while explaining the Pixel engine. For the rest of the brush engines, we will only go over the unique settings that haven’t been covered. I try to provide examples for settings that are hard to describe.

If you really want to understand what these settings do, I encourage you to actively play around with the brush engine settings as they are being explained. Let’s start with the first setting for the Pixel engine.

Brush Tip Setting

Determine what you want the tip of your brush to look like. You can only have one type of brush tip selected. Changing the type will reset any settings that might have been done in other brush tip types. The different brush tip types are seen below.

The brush tip can only have one type. There are three different brush tip types you can choose from.

Auto Brush Tip

Define your brush tip with a series of sliders and checkboxes. Many brushes need simple tips, so this can be a quick option. In the following example, I am slowly adding more properties.

The Spikes setting will only be visible if your brush is noncircular. Also notice the similarity between the Randomness and Density settings.

The Randomness slider takes the pixel information and randomizes it on the canvas. The Density slider takes pixel information away as the slider is decreased.

Warning

The Randomness setting is significantly more computer intensive than the Density setting. Try to avoid the Randomness setting at all cost. It can make your brush strokes very slow.

There are some basic shapes you can select on the left side of the Brush Tip setting. These allow you to see a preview of the shape and specify a mask.

Precision Setting

When it comes to creating brushes, sometimes quality comes at the expense of performance. Having a really large brush can slow your computer down. The Precision setting tries to solve this quality versus performance issue. The precision values range from 1 to 5. When Precision is set to 5, the brushes will be drawn at maximum quality. When Precision is set to 1, the brush quality decreases, but the performance will increase. By performance increase, I mean that the brush will have less lag and keep up with your pen movements better.

There is also an Auto checkbox to the left of Precision. This lets you configure a couple of settings to determine the precision level. There is a little bit of math that goes on with how this works.

• Starting Brush Size – 0 to 99 px. This will be the starting pixel size when the quality will be reduced. If you use line art and your brush will usually stay under 20, you would set this to 20.

• Delta – 0 to 99 px. This is used as an incremental variable. If set to 10, and your Starting Brush Size is set to 20, the precision will change when these brush size increments are reached.
  As an example, say you set your Starting Brush Size to 20 and your Delta value to 15. This is how your brush quality would change:

• Precision 5 – brush size of 20 pixels or below.

• Precision 4 – brush size of 35 pixels to 50 pixels.
• Precision 3 – brush size of 50 pixels to 65 pixels.
• Precision 2 – brush size of 65 pixels to 80 pixels.

• Precision 1 – brush size of 80 pixels and higher.
  Brush sizes can be as large as 1,000 px, so make sure your Delta value is large enough to give a nice distribution between high and low quality. Some presets have the Starting Brush Size set to 0 px and only have a Delta value. This will use the Delta value to determine what breakpoints will be used. For example, if we set the Starting Brush Size to 0 px and the Delta to 10 px, the breakpoints will be the following:

• Precision 5 – brush size of 10 pixels or below.

• Precision 4 – brush size of 20 pixels to 30 pixels.
• Precision 3 – brush size of 30 pixels to 40 pixels.
• Precision 2 – brush size of 40 pixels to 50 pixels.
• Precision 1 – brush size of 50 pixels and higher.
  While the Auto setting is better because it has more “intelligence”, it is sometimes easier to permanently set the Precision slider to a specific value.

Predefined Brush Tip

Predefined tips store an assortment of brush shapes. If you want to use a custom brush shape like leaves for a tree or stars for a night sky, this will be your destination.

The text field below the brush tip shapes allows you to filter the current brush tip by name. If you have a Photoshop ABR file, you can load it in through the Import resource button. You can also load other formats such as PNG and GBR(GIMP). When you import outside brush packs like ABR files, new tags will automatically appear in the brush tip Tag drop-down.

In addition to the shape, you can set starting values of the Size, Rotation, and Spacing sliders. Remember that these are starting values. You can add variability and randomness with the other settings. Don’t forget that we are mostly dealing with the shape of the brush right now.

Create a Brush Tip from a Stamp

Create your own brush tip from the canvas. All of your layers are combined and the result is used. You probably don’t want your entire canvas to be the brush tip though. To use part of the canvas, you will need to draw a selection around your brush shape.

The Stamp brush dialog: I created a selection around the brush tip to determine what is used.

Once you have your brush shape selected, go back to the brush editor. You will see a Stamp button in the Predefined Brush Tip area. A dialog will open to show you the options (like image above). The stamp preview shows you what the final brush tip will look like. When you are done, click OK. The brush tip will be added to your predefined brush tips.

The options for the Stamp dialog are the following:

• Name – The name of the tip when it is saved to the predefined brush tips.
• Spacing – Determines how much space will be used between brush dabs.
• Create mask from color – Converts the tip shape to black and white colors. This grayscale image will be used to determine the mask. White areas will become transparent, while black areas will become opaque.
• Brush Style – Pick between a normal (Regular) brush or an animated one.
• Selection mode – Only used if Brush Style is set to Animated. This will determine which brush is selected. See below for more details about the animated brush style.

Animated Brush Styles

Add variety to your brush tips by using more than one. This brush style is called animated, but calling it something like multiple brush tips would be more accurate.

The animation brush style does not understand selections when the tip is being created, so it is easiest to start a new document. For this example, we start with a 100 px x 100 px document. I created four layers that each have a different brush tip. I drew numbers so you can understand the concept better. Make sure all of the layers are visible.

Setup for an animated brush tip: This is done in a separate document.

Now go into the brush editor in the Stamp dialog and set the Brush Style to Animated. You will see a few different selection modes.

• Constant – Only shows the first brush tip of the sequence.
• Random – Randomly uses a brush tip from the layers.
• Incremental – Goes through each tip sequentially when determining which brush tip to use.
• Pressure – Maps the pen pressure to the layer order. The lowest pressure will apply the top layer graphic, while the hardest pressure will apply the bottom layer graphic.
• Angular – Brush tip will change based off movement angle of the pen.
  There are not many brush presets that use the animated brush tip. You can see that using multiple brush tips can create some randomness and make your strokes more interesting.

Create a Brush Tip from the Clipboard

Create a brush tip from the clipboard data. This is accessed from the Predefined Brush Tip area. Selections that are copied via Edit > Copy or Ctrl + C will be used to determine the brush tip shape. When you open up the brush editor after copying a shape to the clipboard, you will see the thumbnail in the Clipboard dialog. If you don’t have anything copied to the clipboard, you will get a message in the thumbnail area. This can be useful for copying images from the Internet or other graphic editors.

Text Brush Tip

Use text for a brush tip. This is the last brush tip type. The Pipe mode option will use one character at a time while painting. Fonts sometimes are made up of designs like Wingdings, so there is an opportunity for creativity here. There is no brush size for this. You will need to change the font size manually from the brush editor.

Using a shape font instead of text: Websites like
<http://www.dafont.com> have a good selection of these under the Dingbats category.

Blending Mode Setting

Blending modes tell your paint strokes how to interact with the layer below. The normal blending mode will apply your brush strokes in a natural way. Selecting other blending modes like Multiply will darken the image. The blending modes are organized into categories based on their effect.

The Eraser button is a toggle button that will change between your current blending mode and the Erase blending mode. It is Krita’s way of erasing things. This setting is a frequently used feature, so you can toggle it on the top toolbar as well.

It is required to have a blending mode. This is why there is no checkbox next to the setting. Whatever you select is also used for the Blending Mode on the toolbar (to the left of the Eraser mode button).

Strength Property

Many of the settings on all of the brush engines have a Strength slider property on the top.

Control the overall effect of the setting. The values normally range from 0 to 1.

The strength will make your effect more or less prominent. A strength of 1 is similar to 100%. A strength of 0 will be like turning the setting off. The range of numbers can be different for the slider.

Change the strength of the Scatter setting. The top stroke shows full strength. The bottom stroke shows no strength.

Color Smudge Engine

The Color Smudge engine allows you to create brushes that have blending properties as well as painting properties. Even though the name of the engine uses the word “smudge”, these brushes fall under two categories: blending brushes and smudge brushes. The blending brush focuses more on mixing existing colors, while smudge brushes tend to focus on blending in addition to adding new colors.

With most of the brush engines, it is best to start off with some examples of the brushes that come bundled with Krita. We can analyze the strokes and see what gives them their special characteristics.

In the previous example, I am using the Basic_mix brush. If you open the brush editor and select the Color Smudge engine, Basic_mix will be the first preset. In the previous image, I slowly added pressure as the brush stroke moved across the canvas. This is a deceptive assumption though. Take note that there is an “invisible” element going on as well. Only until our smudge brush starts interacting with other colors will we see this interaction.

This example is similar to our first. I created vertical strokes along the gray rectangle. As I make strokes from left to right, I am increasing the pressure on the pen. The left half has only smudging, while the right half slowly adds more orange. The far right stroke is at 100% pressure. You can see that there is very little smudging going on—only the new darker value added. This smudge brush has two purposes: adding color with higher pressures and blending with lower pressures.

While this isn’t a natural way to paint, it is nice when you need to alternate between adding new colors and blending existing ones. This marriage of adding color and blending is a common pattern that is used with smudge brushes in Krita.

In other painting programs, we expect the blending behavior but not the color being added. What if you are creating a brush and want only smudging? There are other presets such as Smudge_textured and Smudge_rake that can accomplish this. How would you turn off the “adding color” part of it?

The Color Smudge engine includes many attributes and properties that aren’t part of blending. This is powerful but can make it difficult to understand how to tweak the existing settings. The properties that are unique to the Color Smudge engine are the following:

• Smudge Length – Switch between Smearing and Dulling.
• Smudge Radius – Sample a larger radius when performing smudging operations. The effect is seen with the Dulling mode.
• Color Rate – Determines how much color to apply to smudging. Turning this off will stop your brush from emitting paint.
• Overlay Mode – Uses all visible layers for determining what to smudge.
  Changing the Smudge Length will control how your brush strokes will smear with underlying colors.

Going back to our original question, it looks like the Color Rate property is adding the color. If we uncheck the Color Rate settings and start to paint, we will notice that color will stop coming out.

Smudge Length: Smearing or Dulling

Let’s take a closer look at one of the most important properties of the Color Smudge engine—the Smudge Length property. If you turn the Smudge Length property off in the settings, you will smear colors without mixing them.

You can see in the example above that the smudging becomes difficult to control. Back in the settings for the Smudge Length property, you have two types of smudging available: Smearing and Dulling.

I turned off the Color Rate for the example above to eliminate any color being added. You can see that the smearing has more of a finger painting feel to it. Dulling preserves the brush shape and size, so it won’t fade off like it does with smearing.

While you can adjust the Strength of this effect between 0 and 1, I would not recommend straying too far away from a value of 0.7. High values will make the blending appear watery and difficult to manage. If the strength is too low, the effect will be weak.

Sketch Engine

Create brushes that have a rough and sketchy feel to them. This can make excellent pen brushes or anything else that might need a “leaky” feel to it. In addition to the leaky feel, there are also some behaviors that will affect the brush’s appearance when it is close to other strokes. The settings that are unique to the Sketch engine are the following:

• Brush size – Controls the area of effect for the brush. This is normally done with the Brush Tip setting. The Brush Tip setting is ignored for the Sketch engine. You will need to go into the brush editor to change the brush size. The Size slider on the toolbar will usually have little effect.
• Line width – Sets the thickness of each brush stroke. There is another size setting that is usually used for this.
• Offset scale – When your brush strokes curve, this determines how the connection lines are placed. This works in relation to the Offset scale slider in the Brush size area.
  The other property is Density (illustrated below). By density, Krita means the density of the connection lines. As with everything, you can modify the curve to get the result you are looking for.

The quick examples below use different brush settings in the Sketch engine. You have to be careful when using the Density setting when drawing. The density creates a hatching effect. This can be unwanted when you are trying to do line work.

Because sketching is usually done with small brush sizes, you will notice it becomes troublesome when you try to erase. This is because the eraser brush size is the same size as the brush size. This draw/erase workflow problem can be alleviated by enabling the Eraser switch size option in the brush editor and making the eraser larger. This workflow improvement allows you to quickly go back and forth between sketching and erasing without having to change the brush size constantly.

Brush Size Properties

In addition to the line width that we discussed, there are a few additional options.

• Offset scale – How long the hatching lines will be.
• Use distance density – The hatching effect will only work when lines are closer together.
• Magnetify – Turn on the hatching effect when the lines get closer.
• Random RGB – Randomizes the hue as you are drawing. Even though it says random, it usually stays close to the original hue. For example, blue will only expand to greens and purples.
• Random opacity – Each brush sample that is applied will have a random opacity.
• Distance opacity – When you move your pen fast when painting, there will be gaps.
• Simple mode – If you turn this off, the magnetify effect will stop working.
• Paint connection line – A line that follows your brush stroke. If you have this and magnetify turned off, the brush will not output anything.
  1. Random opacity effect 2. Distance opacity effect

Bristle Engine

Paint brushes are made up of a bundle of hair or nylon. Each piece of hair is often called a bristle. The goal of this brush engine is to simulate a real brush. In the real world, traditional brushes all have a round point, but that does not have to be the case in Krita. One of the most unique things that the bristle engine can do is closely simulate a brush as the size becomes larger.

Making your brush size larger will add more bristles to the brush, simulating how a real brush would behave.

In this example, I am using the same brush at three brush sizes: 10 px, 20 px, and 40 px. You will notice that as the brush size becomes larger, there are more bristles that are added. You cannot have this behavior on the Pixel engine. Smaller brushes physically cannot have as many bristles to paint with. This behavior can provide some variety in your artwork instead of simply scaling your brush tip up and down.

Bristle Options

• Scale– Scale your brush size up or down. The effect is similar to adjusting your brush size. Negative scaling will invert the brush tip.
• Random offset – Similar to scattering. Higher numbers will increase the distance between bristles.
• Shear – Shears individual bristles when painting.
• Density – How many bristles to apply. Lower values will have a more spotty look. This will be applied in addition to the Brush Tip density.
• Mouse pressure – If drawing with a mouse, this setting simulates pressure at the ends of your stroke being lighter.
• Threshold– This is a graphics tablet feature. When you turn this on, only bristles that are able to “touch the canvas” will be painted.
• Connect hairs – Adds connecting lines to bristles to get a scratched look. This effect is dependent on your Random offset.
• Anti-aliasing – Smooths the brush tips that are applied on the canvas.
• Composite bristles – A difficult-to-see effect that combines the bristle colors within one dab.

Ink Depletion

This controls how much painting you can do before your paint “runs out”. The higher the number, the longer the brush will continue to paint.

• Opacity – As you make your stroke, your brush opacity will be reduced.
• Saturation – As you make your brush stroke, your saturation will become more gray.
• Soak ink – Picks up the underlying layer when making a stroke. This works similar to a smudge brush.
  Note

Turning on Saturation Weights will turn off the Opacity portion, so your ink will not become transparent.

Saturation Weights

These control the saturation values based on different brush parameters. These settings are tricky since they use percentages of properties.

Shape Engine

With Shape brushes, you can create strokes that will autofill. This engine was originally ported from an existing free tool called Alchemy. The shape engine has more limited features than Alchemy.

In the left example, for every line I made, I traced back over it. This creates a leaky, energetic line style. In the right example, I paired a shape brush with the Mirror Tool. If you set the background color to the canvas, you can “erase” with the same effect.

While there aren’t as many settings as Alchemy, it does provide some convenient brush stroke options.

• Speed – Amplifies your pen strokes along the x and y position.
• Smooth – Without smoothing, your brush strokes will have an angular look when making quick brush strokes.
• Displace – As you draw, the entire shape will be moved in the opposite direction of your brush stroke. You will have to test this out to really understand this. To produce the effect more prominently, keep your pen down and continue to draw.
• Winding fill – Overlapping shapes will stay filled instead of being hollowed out.
• Hard edge – Creates aliased, hard edges. This is useful when you are blocking in colors and want to lock the transparency. This also works nice when using the “color split” option.
  The winding fill is turned on with the right image. Turning this on is easier to control, but having it off can give your line work more energy and chaos.

Spray Engine

Create a spray can or airbrush type of effect. While at first this type of brush would appear limited, you can do some interesting things with it when you push the settings.

The above example demonstrates the different spray effects that can be achieved by changing the settings in the Spray engine. This includes normal spray effects on the left to a more exotic effect on the right. For the example on the right, I drew a rectangular selection to keep everything inside. The brush has an extreme aspect ratio, so that is what gives it the horizontal feel. We’ll go over the different parameters you can play around with.

Spray Area

The spray area is the radius of the spray effect. The spraying effect generates particles, so there are multiple properties that can be modified.

• Diameter – How large the spray area will be.
• Aspect ratio – How much the brush will be squashed horizontally or vertically.
• Angle – Rotates the brush tip angle.
• Scale – Similar to the diameter. The scaling will affect the distance as it is changed. It is usually best to leave this at 1.
• Spacing – How much space there will be between each brush dab.
• Particle Count – How many particles will be applied for each dab.
• Particle Density – Percentage of how many particles will be applied. This setting can really slow down your computer, so try to keep the setting low.
• Jitter Movement – How spread out the particle clusters will be. Higher values will spread out the particles more.
• Gaussian distribution – Your spray area will be focused around the center.
  The Gaussian distribution stroke on the first image above has its spray effect focused on the center. The normal distribution will have an evenly distributed spray area.

Spray Shape

Each individual particle that sprays out will have its own shape. There are a few properties that you have control over. If this setting is unchecked, the Brush Tip settings will be used.

• Shape – Select the brush tip with how each dab will look. The two most common ones are ellipse and rectangle.
• Width – How wide each paint particle will be.
• Height – How tall each paint particle will be.
• Proportional – Change the width and height sliders to a percentage. This is useful when you want the size to change depending on the spray area diameter.
• Texture – If you have Image selected from the Shape drop-down, you can use an image as your brush dab.

Shape Dynamics

Randomize the size and rotation of your spray area.

• Random size – Takes the size of the spray area and randomly pick a size. If you want more control over the size, think about using the Size setting instead.
• Fixed rotation – This seems to do the same thing as the Angle option in the main area of the Spray engine.
• Randomize Rotation – The range of values the rotation can be set in.
• Follow cursor weight – With a value of 1, the brush shapes will all point toward the cursor. With a value of 0, this option will not have any effect.
• Angle weight – The brush tip will be rotated according to the direction of your drawing movement.
  Follow Cursor

Angle Weight

Fixed Rotation

The shape dynamics deal mostly with rotation. You need a rectangular brush tip like the examples above if you want to see what the effects are doing. Most of the spray brushes use circular brush tips, so the shape dynamics will not appear to do anything.

Color Options

Randomize various components of the color. This includes changing the hue, saturation, and value. It also has additional options for randomizing opacity. These options can be used to create variety in every stroke you create.

Hatching Engine

The Hatching engine simulates a hatching effect that is common with line drawings. This is commonly used when grayscale values cannot be used while printing—saving money. The pressure you apply sometimes makes your result darker, while other times (like the third example) it will make the brush larger. Some brushes give results more like sketching, while others give results more like applying screen tones.

A few different hatching styles and effects

Hatching Options Setting

Here we will find options to control how the hatching will appear as the stroke gets darker. You can also offset the hatching positions by changing the origin x and origin y values.

Crosshatching Style

Once your strokes become dark enough on the canvas, your hatching will turn into crosshatching. This will make the result be more filled in. These are the crosshatching effects that you can add.

Grid Engine

It is easiest to think of this as sort of high-definition (HD) pixel art. This will take a shape, such as a square or circle, and create a grid of shapes. Your strokes will always be locked to this grid, so you cannot completely fill everything. The grid will change whenever you change the brush size.

Brush Size

The Brush size setting contains a few options that deal with the grid sizing.

• Grid height & width – Specify the height and width elements in pixels for the brush.
• Division level – Make the shape smaller and divide it up evenly. Higher numbers will give you smaller shapes.
• Division by pressure – Divide the pattern into smaller chunks. The effect will change depending on the pressure from your pen.
• Scale – Scales the overall brush size. This keeps the aspect ratio the same.
• Vertical and Horizontal border – Spacing that will be created between each grid shape.
• Jitter borders – Adds randomness to the height and width for every brush stroke.
  You are limited with what brush shapes you can use. These shapes are found in the Particle type setting. The two most common shapes are ellipse and rectangle.

These two examples demonstrate what grid brushes can accomplish.

Color Options

The last unique setting is the Color options. These add variability to each brush dab.

• Random HSV – This checkbox enables the ability to randomize hue, saturation, and value properties. Setting each property to zero will have no effect on your brush. Higher values will add more variability.
• Random opacity – Each particle will have a random opacity.
• Color per particle – When Division by pressure is on, each particle can potentially have different colors.
• Sample Input layer – Only paints on areas that have color information on them.
• Fill background – The area behind each particle will be filled with white.
• Mix with background color – Using a low pen pressure will add more of the background color to each particle.

Curve Engine

Create strokes made with connected lines with this engine. It is best to show a few examples to get the idea. The left example below shows the strokes as they are made. The right example shows the Curve engine being used for line work. The Cazu Brush Collection has an excellent curve brush. You can download the entire brush set for free from the Resources area on krita.org.

There are two elements that make up the brush stroke: the connection line and the curve line. The connection line is the line that you draw with your pen. The curve line is all of the extra lines that are automatically generated. One of the options on the bottom is Paint Connection Line. If you turn that off, all you will get is the curve lines.

• Line width – How thick the line should be.
• History size – Distance between curve lines.
• Curves opacity – How visible the curve lines will be.
  The History size property will be the key to achieving a more dramatic curve effect. High values will produce more extreme and exaggerated lines.

Dyna Engine

This is the engine used for the Dynamic Brush Tool. It is nice to use with the Dynamic Brush Tool in the toolbox but unruly when trying to use as an engine. The brush size setting has two tabs for all of the properties: Dynamic settings and Shape settings. The Dynamic settings will control the brush size, mass, and drag. The Shape tab has effects that control what the brush tip will look like. I usually stick with the Dynamic Brush Tool for its smoothing options and ignore this engine.

Particle Engine

This engine has as a similar effect to the Curve engine but gives smoother, more smokelike effects. There is no connection line like there is in the Curve engine. The absence of a connection line will give the result a smoother effect.

The unique settings to the engine are all in the Brush size area. Increasing the particle size will give you more lines and make the brush appear to get larger. The dx and dy scales will affect how much your brush strokes speed up as you move your pen. Using negative values gives unexpected results, so be careful with this setting. The Gravity option is also tricky. The default is .986, simulating gravity on Earth. Higher values will make the brush go faster. Modifying the Gravity option can quickly make your brush unusable, so be careful with it.

Clone Engine

While this is an engine, it functions as more of a photo editing tool. As the name suggests, this tool allows you to clone an existing part of your canvas and apply it to a different part. The unique settings that will control the clone features are in the Painting Mode.

• Healing– Turns the cloning functionality into healing. When you create brush strokes from the source, it will do a better job at smoothing out what is currently there—similar to the healing brush in other applications.
• Correct the perspective – This checkbox becomes active once you use the Perspective Grid Tool, not the Assistant Tool.
• Source point move – Turning this off will turn your clone point into the brush tip. The source point will not move as you make your stroke.
• Clone From All Visible Layers – Uses all layer information to use as source point.
  Press Ctrl + Click on the canvas to select a source point. This source point will be used to copy from. When you start painting on the canvas, the brush stroke will look at the source to get its brush information. As the instructions say on the tool, you can clone from a different layer by selecting the layer and pressing Ctrl + Alt + Click. Outside of photo retouching, I haven’t found much use for this.

Deform Engine

Apply liquefy effects to your image. Push, pull, grow, rotate, and bend your artwork. The Deform setting will contain all of these options.

• Brush size – Control the diameter, angle, density, and other options for the brush shape.

• Deform Options – Customize how your brush will distort and deform your image. The first set of options will decide the behavior. The Deform amount will make the effect stronger.
  The remaining checkbox options don’t really have much of an effect, so you can probably leave them as is.

• Bilinear interpolation – Smoothens the results slightly.

• Use contour – Slows the final effect down a bit.
• Use undeformed image – Samples from the previous version for the source.
  Using the Swirl CCW deform option can help create interesting effects.

Filter Engine

Instead of painting with colors, paint with an effect. This is great to use if you want to apply a filter to a small area. This engine contains a Filter setting that lets you change what filter to apply. Many of the filters aren’t available to use for this engine, so keep that in mind. You will have to use something like a filter mask to achieve similar results.

A few of the filters that I have found the most interesting are the Motion Blur, HSV/HSL Adjustment, and Unsharp Mask.

You can use a Filter brush to paint on effects. This example uses the HSV/HSL Adjustment as the Filter setting.

Chalk Engine

This engine simulates a chalk effect. While the name sounds like this engine would be useful, it was actually created as more of a programming base for other brush engines. Because of this, the options are limited. You can use the Pixel engine to do everything that the Chalk engine can accomplish.

Tangent Normal Brush Engine

With this engine, you can create normal maps for your textures. I included this engine last because it is a bit obscure, and many artists will not have a use for it. It is mostly used by texture artists that need to move their images to 3-D applications. This is the only engine that needs to be set up before it can be used. Knowing how to set up your layers is essential.

Here is the layer setup needed to create normal maps. If you create a lot of normal maps, you could create a template to speed this process up.

Make sure the layers are in the same order as the image above shows. The Normalize filter layer is added to make sure the colors will output correctly. You will see a minor shift in colors when you toggle the visibility. The Background layer must be filled with the RGB color (128, 128, 255). You can set the background color when you create a new image or choose an exact color through the foreground color chooser in the toolbar. The Painting layer will be used to make all of your strokes. Select a Tangent Normal engine preset and start painting.

The optional filter layer with PhongBumpmap will give you a grayscale preview of the output. Through the properties in the filter layer, you can change and add lights to see the final effects. Also in the layer properties, make sure to enable the Use Normalmap checkbox for it to work. This filter layer is only good for previewing, so make sure to hide it before you export the image.

Two normal maps that were applied to a 3-D model on the right.

Tip

Combine Wrap-around mode with the Tangent Normal engine. This will help make your textures tile correctly.

Depending on what 3-D application you are using, you might have to alter the Tangent Normal preset settings. The Tangent Tilt setting has all of the unique options for this engine. You may have to change the Tangent Encoding area with how each axis is mapped.

This engine gets quite technical. If you are interested, I would recommend checking out krita.org for more in-depth information.

Learning More About Brush Engines

As I have stated a couple of times already, the brush engines are very deep. This is the longest chapter in this book and I could have easily made it twice as long! Hopefully what I have provided has given you a good grounding on how the brush editor is organized and functions. From here, you should be able to experiment and modify brushes to your liking.

The documentation that Krita provides on the brush engines is good
(https://userbase.kde.org/krita/manual). Sections like the bristle engine (previously called hairy engine) are a little sparse so you might have to do a bit of digging to understand the settings. Even though I have spent time studying this, I still consider myself a novice. There are a lot of creative brushes that have yet to be discovered. If you create some interesting brushes, share it online!

Artwork by Sylvia Ritter

<http://www.sylvia-ritter.com>

Chapter 9 - Working with Color

Colors have their own chapter, and rightfully so. This is one area in digital art that is deceptively complex. While it is important to know about how to select different colors, it goes much deeper than that. Everything has colors in Krita: the application, the image, and every layer. In addition to storing color information in the document, Krita also needs to know about your monitor and how it displays color. Sending your artwork to a printer will also require special care. You will need to make sure your document is using the correct color model.

Some of the color concepts might seem like magic. Having a deeper understanding of color management can help your images look the best when they are used outside of Krita.

We will start off with the different methods to select a color. As we progress, we will continue to look at some of the advanced color management options. This can help you work faster and ensure your images look the best. We will end by briefly going through High Dynamic Range (HDR) painting and what it has to offer.

Selecting Colors

Advanced Color Selector Docker

When you start Krita for the first time, the first thing you will notice is the big color selector on the top right of the screen.

The Advanced Color Selector has a lot of options that are shown by default. It can also be configured to a great degree. The settings option in the top left corner allows you to configure what is shown. When the options are open, you can navigate to the Color Selector tab and change the Color Model Type and image drop-down on the left.

Selecting the settings icon lets you customize the Advanced Color Selector docker.

The shade selector shows different variations on your current color selected. This docker also shows you a history of the colors you have picked. It will be automatically updated as you continue to paint.

Digital Colors Mixer Docker

Mix other colors with your current foreground color. You have up to six different color columns that you can play around with. The bottom portion of each column will show you the color to mix with your current color. The color gradient slider will show different amounts of the color to mix. The top color swatch in each column is the resulting color. When you click this top color swatch, your foreground color will change. The color mixing process then starts over.

Pop-up Palette

Quickly select colors and common brush presets. You can access this by right-clicking on the canvas at any time. The inside color wheel is for selecting new colors. The color segments in the middle ring show you recent colors. The two color half circles on the outside show you the foreground and background colors.

Like the other color tools, when you change your colors here, the colors will be updated in all of your color selectors and tools.

Color Selector Tool

Quickly select a color on your canvas to use. This tool can also be accessed by holding down Ctrl while on the canvas. This will temporarily select the Color Selector Tool.

Specific Color Selector Docker

If you know you need a specific color, you will find this docker helpful. You can simply specify your color model and select a specific color.

Clicking the checkbox will reveal options to show color selectors in other color models.

The foreground color selector in the toolbar has most of these options, but this docker can be faster. The Color name field shows the hex value that is often used in website design. If you want, you can click Show Colorspace Selector to determine what color sliders to show.

Small Color Selector Docker

This condensed docker provides another way to select a color. The area on the left selects the hue, while the area on the right selects the value and saturation. If the advanced color selector is too complex and big for you, this might be a good alternative.

The docker elements do not scale larger if you try to resize the docker.

Artistic Color Selector Docker

This docker reduces the amount of colors you have for your palette. Configure your color wheel to show less available colors. You cannot limit the color ranges, though. For example, you cannot filter your colors to only show complementary or triadic values.

If you hold down your pen on a color segment, you can spin the wheel to change the hue. As you select different light pieces, your color wheel will become darker or lighter.

Palette Docker

Select from a predefined set of colors. You can add or remove from an existing palette or create your own. You can even change how many columns to display from the options.

Foreground/Background Toolbar Selector

The foreground and background selector gives you a few options on the toolbar to select and change your colors. Double-clicking one of the color swatches will bring up a color picker dialog.

Color Selector – Pick a foreground or background color. The bottom left icon allows you to flip the foreground and background colors.

Common Color Selector

This selector analyzes the canvas and shows the most used colors. The refresh button needs to be clicked for the color swatches to be updated. The colors won’t be accurate if you only have one color on the canvas. You can configure this selector through the main menu Settings > Configure Krita > Color Selector Settings > Advanced Color selector drop-down > Colors from Image tab. Changing the Patch Options with size and amount will update the common colors display. Shortcut: U.

The refresh button will scan your canvas and update the colors. The amount of colors and size of each color patch are configurable.

Helpful Shortcuts

Minimum Color Selector pop-up: Shift + N.

Shade Selector pop-up: Shift + M.

Color Management

Color management is the language that helps all of your devices talk to each other about color. Your scanner might scan your artwork with certain color settings. Your monitor will display colors in its own way. Your printer will use its own settings when applying ink. Moving color information across different devices and keeping them accurate is what color management is about.

This is important for us to know because our documents are created with color information. If we don’t understand what is being saved, it can make it difficult when sending it to a printer. The colors might also appear differently if we send it to another application.

To keep your colors the same across devices, an organization was created called the International Color Consortium (ICC). They created a measuring stick by which all devices try to follow for color management. Not only does this standard specify how a color should look, but how colors are converted to different formats. This whole process is referred to as a Color Management System.

Color Models

The colors that we know like green, red, or violet are only a small portion of what exists in the world. Color is a small portion of the entire light spectrum. Light itself is a portion of a larger system called an electromagnetic system.

Only a small portion of this system can be seen by humans. The portions that can be seen are what we know as colors. This is why a sun setting can make different colors appear as it moves across the sky. As the light waves become longer, the color changes.

In terms of creating art, we only care about the visible portions of light. This is where the idea of color spaces, or color models, comes from. There are many different models that are used to define and show color. Do we need to know them all? Not really.

Color Models for the Artist

When we create artwork on the computer, it will be printed out or viewed on a computer monitor. There are two color models that we need to worry about.

RGB (Red, Green, Blue) is what a computer monitor uses. The RGB color model has a larger gamut, or range, of colors than CMYK. This means there is more data stored. Most artists tend to work in RGB first, then convert the image to CMYK if needed.

CMYK (Cyan, Magenta, Yellow, Black) is what printers use. If you decide to print your artwork, you will switch the color model to CMYK. Printers usually have four separate ink cartridges that store these colors. When you convert an image from RGB to CMYK, you destroy some of the color information.

Chromacity

Chromacity comes up in discussions when people are comparing color models like RGB and CMYK. When the word chromacity is discussed, it is usually along with a chromacity diagram.

The diagram is commonly used to show how many colors exist in a color model. It has the name chromacity because it shows colors relative to gray. It does not show lightness.

The chromacity diagram shows a visual representation of all of the colors that are visible to humans. Don’t worry about all of the numbers on the chart above. They are rarely referenced when artists talk about color models. The diagram is a representation of all colors that exist, so the exact colors cannot be shown.

When people compare color models, they put different shapes inside the chromacity diagram. This helps show how many colors a model like CMYK includes.

The following example shows the CMYK and RGB color spaces in a chromacity diagram. The RGB color model has more colors included than CMYK. Many colors do not exist in either of the color models. It also brings up an interesting question of what happens to colors when you start converting them to different color models.

Note that there is no black, or darker colors, in the chromacity diagram. There are many different properties of light and color such as chroma, intensity, and luminance. The darkness of color is measured differently than what the chromacity diagram shows. While these advanced properties are nice to know, they won’t serve much of a purpose with normal painting.

If you are interested in learning more about this subject, a quick Internet search can get you good information. While it is nice to have an in-depth knowledge about this, it ends up having little practical use when creating artwork.

Other Color Models to Know About

Krita additionally comes with more colors models besides RGB and CMYK. You can get by without ever using these, but I will provide a quick overview if you are interested.

• Grayscale – This will force your artwork to only contain grayscale color data, which is useful if you want to work in only black and white. Your color selectors might still show colors, but your canvas will only show the grayscale value.
• Lab* – A transformation color model that is used when converting between color spaces. It includes imaginary numbers that cannot be seen. Some artists like working in this color model because it includes all colors in CMYK and RGB.
• XYZ – A transformation color model that is used when converting between color spaces. It includes imaginary numbers that cannot be seen. It is safe to ignore this.
• YCbCr – This color model was used more in the past when cathode ray tube (CRT) monitors were used. It is rarely seen in images now.
  The reason why Krita includes these extra color models is more of a developer reason than an artistic reason. The developers use an outside color management system called Little Color Management System (Little CMS) that they try not to alter.

Color Profiles

In addition to the data that color models provide, there are also settings with how hardware devices display color. The color models that we learned about earlier are more of a data thing. Color profiles are more of a hardware thing. Your scanner and monitor have a color profile attached to it. This is oftentimes assigned automatically but can sometimes be incorrect. If the color profile is configured wrong for your scanner, what you see from the scanner software might appear different than what appears in Krita. These are the types of things that have color profiles associated with them:

• Monitors
• Input devices (scanners, cameras)
• Output devices (printers)

• Documents (jpg, png, Krita file)
  Specifying a color profile will help your computer determine the best way to manage and convert colors when going between devices. These color profiles use different systems than color models (RGB, CMYK). Some of the most common color profiles included in Krita are the following:

• sRGB (default) – Standard RGB. Created in 1996, it is used with monitors, printers, and the Internet. It’s a good profile that you can stick with if you aren’t a color fanatic.

• scRGB – Contains the same colors as sRGB, but the data can include negative numbers. This is more useful if you are thinking of doing HDR painting.
• AdobeRGB – Has more colors available than sRGB but is less supported.
  Quite a few of the color profiles that come with Krita are from the color enthusiast Elle Stone. It can be a bit difficult to understand what each of these color profiles do. To learn more about a color profile, Krita comes with a color space browser. This is located in the New file dialog box. When you click the Color Space Browser button, a dialog will appear to help you study what the color profile and color model are doing.

The color space browser is an excellent way to visualize a color profile as well as learn a little more about why it exists.

You can always stay with the sRGB color profile and not really worry about it. The Internet has an abundance of information if you are interested in learning more. I recommend going to Elle Stone’s website as she is considered to be a credible authority on the subject: <http://ninedegreesbelow.com>.

Converting Between Color Models

If you are working in the RGB color model and want to send it to a printer, you might need to convert your image to CMYK. To convert your image to a new color space, go to the main menu Image > Convert Image Color Space. You will see some options grouped under the Rendering Intent group. When you convert a document to CMYK, you will lose some color information. This is because the CMYK color space has less available colors than RGB. The Rendering Intent lets you determine how to handle this reduction of color.

• Perceptual (default) – Takes all of your values and scales them to fit in the converted color space. Since all of your colors change proportionally, your image will still look pretty good.
• Relative colorimetric – If a color is outside of the color gamut, it will be mapped to the closest color. If the color exists in the target color space, it will be left alone.
• Saturation – The saturation of the colors are preserved over other color attributes. This is useful when exact colors are needed such as in business logos.
• Absolute colorimetric – Tries to reproduce the exact colors that were used. This usually produces color banding or shifting that is undesirable.

Converting a Layer to a Different Color Model

You can convert a single layer to a different color model than the other layers. For example, you can have one layer be grayscale for your sketching and another layer be in RGB for painting. When you paint on grayscale layers, you will have a small performance increase since your computer doesn’t have to deal with colors. You can do this by going to the main menu Layer > Convert Layer Color Space.

Each layer has a color profile associated with it. While you can change your profile to something different on each layer, there will be extra calculations that go on under the hood. It is best to leave the color profile information alone and only set it at the image level.

Soft Proofing

Preview what your image will look like in a different color space (like CMYK). This is usually referred to as soft proofing. The image isn’t converted to CMYK but displays on your monitor as it would look like in CMYK. The advantage is that you don’t have to destroy your color data to see what a printed version might look like.

This is accomplished through the main menu Image > Properties. Again, this does not change the color model from a data standpoint. If you are sending your artwork to print, you must use Image > Convert Image Color Space from the main menu to change your color data to CMYK.

Color (bit) Depth

For every pixel, there are a limited number of colors that you can use. Changing the color depth will change the amount of colors that can be used. There is a trade-off, though. The higher you raise the bit depth, the slower your computer will become. You will not see much of a difference when going to higher color depths, so the default of 8-bit is usually okay.

The total amount of colors that are available is related to the color channels. If you are using the RGB color model, you will have three channels: one for red, one for green, and one for blue. The amount of colors in each channel is determined by the color depth.

Say we have an RGB document that is set to 8-bit. The 8-bit is describing how many colors each channel has. 8-bit is the same as saying 28, or 256, values. The red, green, and blue channels will each have 256 available colors. Each pixel then has a choice of 16.7 million (2563) colors. These are the different color depths that are available:

• 8-bit
• 16-bit
• 16-bit float
• 32-bit float
  The floating bit depths are used for HDR painting. The values are stored differently. Instead of a 0-255 range, the normal range is 0-1. The advantage of the floating format is that they can include values higher than 1. If you would have a value of 10, this would mean that the value would be ten times higher than white. It is similar to changing the exposure on a camera.

What Is CIE?

You will see the letters CIE a lot if you look at the color profiles. CIE is an acronym for the International Commission on Illumination. They are the authority on light. CIE conducted some experiments in the 1920s to determine the range of light that people could see.

For us to see color, we have three separate sensors in our eyes called cones. They have the names long, medium, and small—referred to as LMS. Your L cone accepts red light. M receives green light. S receives blue light. Some of the profiles and color models use the CIE standard to ground itself in the color format. This doesn’t have to do much with creating art, so I will leave it to you if you want to do further research.

LUT Management (HDR Painting)

If your artwork needs to be used later for compositing (e.g., 3-D applications), this docker can be useful. If you have little need for this type of thing, you can easily skip this section. This is also the section that deals with HDR painting. There is a lot of color and light theory with how light is interpreted. Much of this knowledge doesn’t apply if you are simply going from a computer to a printer.

The Lookup Table (LUT) Management docker helps you change how your color is managed.

This docker controls the color management settings for the document. LUT is short for lookup table. It is helpful to know a little history about why this is included in Krita to understand the value it might have.

A Brief History of LUT and Krita

For Krita to support HDR painting, it uses a technology called OpenColorIO. This technology was developed by Sony ImageWorks in 2003 for their feature films. Sony released the source code for this technology and continues to update it. OpenColorIO is supported in many commercial applications that need to deal with color management solutions.

One of the problems that OpenColorIO solves is how different displays such as projectors or HDTVs can use different color spaces. If the color space that is used is different than what the device supports, the colors will be altered, and the end result will be different than the artists intended.

Using OpenColorIO

To enable this mode, you need to click the Use OpenColorIO checkbox from the LUT Management docker. Once enabled, colors will be managed using OpenColorIO-compliant formats instead of Krita’s internal color management.

Out of all of the settings, the two that you will be playing around with the most are the Exposure and Gamma sliders.

• Exposure– Controls the light and darkness of the document. A higher value will let more light into the image and make it appear brighter. This is a common term used by photographers.
• Gamma – The amount of light that is emitted from the monitor. If uncorrected, images will appear too dark or too light. Images will often appear more washed out if the gamma is not correct.

Selecting HDR Colors for Painting

For the most part, selecting HDR colors will function just like picking normal colors. You can use any of the normal color picking options when using outside color management systems. When you first switch to a different color management system like OpenColorIO, the colors will not update in the pickers. To show the correct colors, you need to change the exposure through the LUT Management docker. As you change the exposure, the color selectors will automatically update their available colors for that exposure.

Changing the exposure and gamma will change the available colors from normal (left) to adjusted (right).

RAW Format

RAW is not like the RGB or CMYK color spaces. The image information isn’t broken down into components like you might expect. Instead, RAW stores data that can be turned into an image. The data itself is meaningless until another process can convert it into an image.

Under the Hood Options

Many of the options that exist in the LUT Management docker will not appear to do anything. These options are more for how color profiles and settings are calculated between the image and the monitor. Here is an overview of the different settings and Color Engines that are available:

• Internal(default) – This will use Krita’s built-in color management system to determine color modeling and information. The Internal color engine ensures that all of the colors are displayed correctly on screen. Most of the options are disabled on the docker when this is selected.
• OCIO – Gives the OpenColorIO engine full control of the color management system for your document. You can load in configuration files that outside applications support.
• OCIO (environment) – Similar to the regular OCIO setting, but the configuration points to your machine’s OCIO environment variable for the configuration.
  Shortcut

Change the exposure level by holding down Y and dragging your pen up or down. Changing the exposure will adjust the light that defines your colors. This will either make your colors lighter or darker.

Configuration Options

If you visit opencolorio.org, you can download some predefined configurations that specific applications use such as Nuke or Sony Picture Works. In the LUT Management docker, the configuration files specify the following properties:

• Input ColorSpace – Specifies the source image’s color space.
• Display Device – What type of device will the final image be outputted to? A common display for monitors is sRGB.
• View – Simulates the way your image looks on a screen.
• Components – How the color information will be separated. This closely corresponds to the channels for the image.
• Lock current color (icon) – Lock the foreground color to have the same appearance when changing between configuration files.
• Configure black and white(icon) – A normalized value range where you can specify where black-and-white values occur.
  Artwork by Elésiane Huve

<http://www.aliciane.portfoliobox.me>

Chapter 10 - Vector Tools

While Krita is focused on being a painting application, it does offer some vector tools. If you haven’t worked with vector graphics before, the advantage is that vector graphics do not get pixelated. This means you can scale them up or zoom into your canvas without the quality deteriorating. The other advantage to vector graphics is that they are always editable. Every curve has points that you can edit at any time.

After working with vector objects for a while, you will realize it has limitations. The nature of vector graphics means extra editing after you create your initial lines. While vector graphics give crisp lines, it can really make your artwork take longer to finish. It also depends on your art style. A cartoon style might work with vector objects, but a painterly style would not.

We will start by understanding how to work with the vector tools. We will then start diving into customizing and modifying objects. There are a lot of options and properties when working with vector objects. Some functions create the objects and fills. There are quite a few options to edit the anchor points as well. We will finally go over the Text Tool and gradient options.

Understanding Vector Objects

The vector tools in Krita are a bit different than most applications. Many of the tools in the toolbox can either work on a paint layer or a vector layer. I didn’t have this aha moment until months after I started using the application. If you use the vector tools on a paint layer, the results will be rasterized. If you use the tools on a vector layer, the results will be a vector format. You can edit anchor points if using a vector layer. You can use transforms if using a paint layer. The tools are type-agnostic and will adapt to your selected layer.

The first group of tools in the toolbox can be used on vector layers: Shape Handling Tool, Text Tool, Calligraphy Tool, Gradient Editing Tool, Path Editing Tool (hidden normally), Rectangle Tool, Ellipse Tool, Polygon Tool, and Bézier Curve Tool.

The next question is usually which type do you use–vector layers or paint layers? Like many answers that are given, the answer is usually, “It depends.” If you are interested in the painting aspect of the program, you will find that you will rarely use the vector tools. Outside of setting up comic book frames and inserting text, the vector tools are easily missed or ignored. Tweaking anchor points and shapes can slow down your process. They do have some benefits though.

Illustrators sometimes prefer the vector format as it gives them the most control with sharp lines. On a paint layer, your painting information gets lost when you paint over existing areas. With vector layers, the lines and shapes are stored separately. Your artwork is nondestructive with vector layers and objects. This comes at a cost of higher maintenance, so be careful.

Creating Vector Objects

When Krita starts, a paint layer will be added by default. For learning sake, let’s see the difference between how a rectangle looks and acts on a paint layer and how the same tool acts on a vector layer. Let’s use the Rectangle Tool and draw a rectangle on the canvas.

Create a rectangle on a paint layer. There is no editing ability after it is on the canvas.

The rectangle uses your current brush to fill in the outline. If we try to go to the Shape Handling Tool, we are not able to select the object to change anchor points. We are on a painting layer, so the Rectangle Tool has turned our rectangle into a bitmap–escaping the world of vector. To edit this, we will have to use the Transform Tool. One downfall with the Transform Tool on a paint layer is that the rectangle will start distorting the rectangle as it grows or shrinks.

Now let’s create a vector layer and do the same thing. We can do this by going to the Layers docker and clicking the drop-down arrow by the plus sign.

Use the drop-down to create a Vector Layer.

Vector layers will have a special icon by them.

Once you have created your vector layer, select the layer. With your new vector layer selected, use the Rectangle Tool again to make another rectangle.

Creating a rectangle on a vector layer gives a different appearance. Notice how thin the line is. The brush stroke we had on the paint layer is not applied.

This time the rectangle doesn’t look like the brush preset. You can try to switch brushes around, but you will notice the rectangle always has a solid thin line. Because the rectangle is on a vector layer, the properties, as well as the shape, are configured in the Tool Options. We can edit the rectangle by using the Shape Handling Tool.

Shape Handling Tool – Select and transform vector objects. Selecting an object will show you the transform handles in blue.

You can click the rectangle now, and it will have blue handles. If we look at the Tool Options now, they are overflowing with properties and options we can play with. We can do anything from changing the visual styles to adding effects like shadows.

For the Arrange tool options, the different buttons will arrange the selected object based on the canvas size. If you have multiple vector objects on a layer, you can also position them in front or back of each other.

Adding Vector Objects to the Layer

Now that you understand the basic process of how a vector object is added to the canvas, you can extend that knowledge to add other vector types. Try to add a few more objects to the canvas and play around with their strokes, fills, and shape properties.

A few vector shapes are added to the canvas. All of the objects are on the same layer.

You can select multiple objects by holding down Ctrl. While you are in the middle of making a vector shape, you can right-click and undo the last point that was added.

Add Shape Docker

In addition to the vector tools in the toolbox, there are additional vector shapes in the Add Shape docker. This docker might not be visible, so you will need to open it from the main menu Settings > Dockers > Add Shape. From here you can drag predefined vector shapes onto the canvas. The last option will present a drop-down of categories like Geometrics and Arrows.

Drag existing shapes on the canvas by using the Add Shape docker.

Note

If you add shapes to the canvas through the Add Shape docker, the object will be added to a vector layer. If you are not on a vector layer, one will be created.

Note

The shapes you use from the Add Shape docker have limited editing functionality. If you want full control over your anchor points, you might want to create the shape from scratch.

Shape Properties

There are two dockers that store properties for the vector shapes: Tool Options and Shape Properties. You can access this by going to the main menu Settings > Dockers > Shape Properties. If you open up this docker and select certain objects like ellipses, you will get a few more options to tweak. For the ellipse object, you can create other types of effects like chords and pie chart pieces.

Primitive shapes have additional properties to customize their appearance.

Modifying Vector Objects

We learned earlier how to create vector layers and add different types of vector objects. Next we need to know how to edit the individual points of a shape. We cannot paint on vector layers, but we can edit the anchor points. With a vector object selected, we can do the following:

• Scale – Resize your object. Grab a corner handle and drag the object bounds.
• Rotate – Rotate the object. Place your cursor slightly outside of a corner anchor point. The cursor will change to a rotate icon.
• Skew – Skew the object. Place your cursor slightly outside of a side anchor point. The cursor will switch to a skew icon.
• Move – Move the object. Place your cursor inside of the object. Dragging your pen will move the position.
  Holding down Shift will lock the aspect ratio while scaling. Holding down Ctrl will scale the object by the center. By holding down Alt, you can constrain the movement horizontally and vertically.

Modifying Anchor Points

In addition to making selections to an object, you can also modify the individual anchor points. To edit the points directly, you need to have a vector object selected with the Shape Handling Tool active. Once the vector object is selected, a new tool will appear in the toolbox.

Path Editing Tool - Edits vector object anchor points.

Selecting the Path Editing Tool will change the blue object boundaries into anchor points. In some versions of Krita, this tool may not appear. You will have to use the mouse and double-click an object to see the anchor points. With shapes like ellipses, you can only modify aspects like the start and end angle.

Hovering over an anchor point will turn the circle red. This lets you know that the anchor point will be selected if you click.

Selecting anchor points can be frustrating. If you don’t select the anchor point exactly, your entire selection will disappear. It is easier to drag a selection around the area that has the anchor point(s). When you drag an area around your selection, everything inside will be selected.

Selecting anchor points is faster if you create a selection. While in the Path Editing Tool, you can create these selection boxes by dragging your pen.

In the figure above, when I let go, the top left anchor point will be selected. This selection technique only works for selecting the anchor points, not Bézier points.

Anchor Point Tool Options

Krita also has the ability to add, merge, delete, and convert anchor points. There are thirteen options that exist. They are a bit unorganized on the Tool Options, so we will break apart the different options by area.

When you select the Path Editing Tool, you will notice the anchor point tool options appear.

Anchor Tool Options: You need the Path Editing Tool activated for these to appear. If you are working with text, you might need to use the Convert to Path button first.

Converting Bézier Anchor Point Types

Let’s take the first three options on the top left. The main thing these functions will modify is how the Bézier points will appear. There are three point types: Corner, Smooth, and Symmetric. The icons are a bit difficult to see with the dark theme, so I will be using the light icons for the screenshots.

Corner Point – The Bézier points will move independently in both direction and length.

Smooth Point – The Bézier points will move parallel to each other but will allow you to change the length.

Symmetric Point – The Bézier points will move parallel to each other. Changing the distance of one point will automatically change the distance of the other point.

Insert and Remove Anchor Points

These icons are located below the first set of icons on the top left. You can select a point and press the Remove point button. For the Insert point icon to be enabled, you will need to select more than one anchor point. You can select multiple anchor points by holding down Ctrl. When the Insert point button is pressed, Krita will determine how many points need to be added to retain the shape. If you are adding points to a simple line, only one point will be added. If the path is a large curve, there will be multiple points added.

Convert Line Anchor Points

The right area of icons modifies how the lines are constructed. These options convert the lines to various vector formats that are common.

Segment to Line – Needs multiple points selected. It removes the Bézier points that are in the direction of the other anchor point. This creates a straight line in the process between the two points.

Segment to Curve – Needs multiple points selected. It adds Bézier points to the anchors if they do not exist.

Make Line Point –Takes the selected anchor points and removes the Bézier points if they exist.

Make Curve Point – Takes the selected anchor points and adds Bézier points if they do not exist.

Shortcut

You can also press the Delete key to remove an anchor point when it is selected.

Anchor Connection Tools

The last four buttons on the Tool Options deal with separating and joining anchor points. Most of them require having multiple anchor points selected.

Break at Point – Separates a single point into two unique points. The result doesn’t appear to do anything. If you select the anchor point and try to move it, you will notice that there are two points now.

Break at Segment – Needs exactly two points selected. This will remove the line that attaches the two anchor points.

Join with Segment – Needs exactly two points selected. It connects the two anchor points by creating a line between them. A Bézier point is created to connect the two lines.

Merge Points – Needs exactly two points selected. When this action merges the two points, it moves the merged point to the center of the two original points. When the points are merged, the original point still exists.

Calligraphy Tool

The Calligraphy Tool has no presets like the Freehand Brush Tool. If you start using this tool and are not on a vector layer, one will be created. Like all of the other brushes, the Calligraphy Tool is pressure sensitive.

Calligraphy Tool – Your brush will be limited based on the Tool Options. You can change the angle, mass, and drag.

Like other vector tools, the calligraphy strokes you make can be later moved, transformed, or edited. Many of the assistants and editors do not work with this, so make sure you know what you are getting into. The normal painting brushes can also produce calligraphy results, so that may be a better option.

These examples use the Calligraphy Tool.

A disadvantage to this tool is that it frequently creates artifacts when you make strokes. In the following image, you can see that the edges and insides break down by the corners and intersections. This can get pretty frustrating if you make a nice shape and experience this. You could edit the strokes with the Path Editing Tool, but this can be time consuming. I generally try to stay with the calligraphy brushes in the Freehand Brush Tool instead of using the vector Calligraphy Tool.

These artifacts can appear when using the Calligraphy Tool.

Note

If you are on Windows, the Calligraphy Tool will be included by default. If you are on Linux, you will have to include Karbon.

Text Tool

While the Text Tool is usually something you can jump right into without instruction, that is not the case with Krita. If you don’t understand how Krita manages text, you will become frustrated quickly.

Text Tool – Adds text to your document with various formatting options. Text will always be in a vector layer.

An important point is that you need to use a mouse when working with text. There are bugs in Krita that will make your pen act chaotically. These pen issues will make the Text Tool seem completely broken. Switch to a mouse, and the problems will disappear. The developers are aware of this issue and hope to fix it in the future.

For creating text, there are two text types: Artistic and Multiline. The Artistic type is made for creating text on a path or breaking it into anchor points. The Multiline type is used for blocks of copy where you need multiple lines and formatting options. The Multiline type works best most of the time, so we will start there.

Multiline Text

To create a text area, click the Text Tool from the toolbox. Now before you get too excited and actually click on the canvas, take a look at the Tool Options.

You will notice that you are presented with a couple of options.

Make sure to select the correct type of text you want before you create the object.

• Mode – The type of text object that will be created: Artistic or Multiline.
• Style – Only used for Artistic type. This will be used for the text color. This can be changed later.
  Once you create your text on the canvas, you cannot go back and change the type later. For now, let’s select Multiline text. Draw a box on the canvas. You will be shown a blinking cursor that will let you type. Type in a few words. Notice that wherever you select on the canvas, your text box will still stay selected. The Tool Options will change while editing your text.

You will be presented with some options that are common in text editing applications. I won’t go over all of the options since they are pretty standard. I will call out a few differences that you might not be familiar with.

The top white text box will allow you to save presets for styles. As soon as you change a setting, such as the text size, a plus icon will appear by the style drop-down. This helps when you need to reuse styles. There are separate areas for Character styles and Paragraph styles. The ellipsis (…) icons at the end of the Character and Paragraph options provide a dialog with even more options. The Paragraph options have a large amount of formatting and features.

Alert

Use the mouse with the Text Tool. There is a bug that causes your pen to behave chaotically. Hopefully this will be fixed in the future.

The easiest way to edit text is to double-click on the text box. The Shape Handling Tool needs to be selected for this to work. You can then press Ctrl + A to select everything. Now you can do things like bold the text, change the color, or edit the font. You cannot edit the line height for text.

Artistic Text

Text On Path

There are times you might want to have your text go on custom paths. This can be useful for placing text on irregular objects or bending text around an object.

The easiest way for this to work is to create a path by using any of the vector tools on the toolbox. Make sure the path is on a vector layer. Select the Text Tool and mark it as Artistic text. Create a text box on the canvas.

Everything needs to be on a vector layer for Text On Path to work.

Edit the text you want to put on a path. You can edit the text by clicking the Shape Handling Tool, then double-clicking on the text. This will make the text box turn into edit mode. Press Ctrl + A to select all of the text. Hover the mouse over the path you want the text to wrap around. Your cursor will change to a hand pointer. Double-click on the path. Your text should now be following the path.

Text will be resized so it fits on the path. The triangle at the beginning controls where the text starts.

You can also change where the text starts wrapping in two ways. The first is to drag the starting triangle below the beginning of the text. The second way is to click the slider below the Text On Path icon in the Tool Options. To remove the text from the path, you can click the Detach Path icon on the Text On Path Tool Options.

Convert to Path Option

If you need to convert the text to anchor points, you can access this function on the Text On Path options. This option only exists when the Artistic text option was used to create the object. Once your text is converted to anchor points, you cannot edit the text or add to it. This conversion is a one-way operation. Converting the text to paths has a couple of advantages.

2. A printer might not have the fonts available, so converting your text to anchor points will ensure that an outside person can view the text.
3. You can edit the anchor points for text. This is usually done to modify typography after it has been laid out.

Vector Gradients and Patterns

When you select any type of vector shape, you will notice there are a couple of tools in the toolbox that will become enabled.

Pattern Editing Tool

Add or edit a pattern on a vector object. When the tool is selected, a blue box will appear that allows you to offset and scale the pattern. With the on-screen controls, you rarely need to adjust the values in the Tool Options.

Pattern editing tool – Have more control over how your patterns are placed and scaled on the object.

You have a few repeat types you can use with a pattern. These repeat types are in the Tool Options.

• Original – Only one instance of the image is used.
• Tiled – The image is repeated horizontally and vertically.
• Stretched – The image is stretched to fit the bounds of the object.
  If Stretched is selected, all of your other options to scale or offset will be disabled. Leaving the option set to Tiled will work in most circumstances.

There are additional options for editing the pattern in the Tool Options. These options do the same thing as manually moving the offset pattern or scaling the anchor points. It is easier to use the blue box instead of manually tweaking the numbers.

Gradient Editing Tool

Add or edit a gradient on a vector object. Like the Pattern editing tool, you need to have an object selected before this tool becomes enabled.

Gradient editing tool – You can move and rotate the end handles on the object to change the gradient. This provides more control than the standard fill options.

If your object has a gradient applied and this tool is selected, a line will appear along with some color swatches below them. Each color swatch along the gradient is referred to as a Color stop. When you have a Color stop selected, you will notice the Color stop option appear in the Tool Options. In the Tool Options, the number to the right of the color is the distance percentage between color stops. It is easier to drag the color stop handle visually.

If you select a Radial gradient from the Tool Options, you will notice an extra point appears on the object, as shown below. This extra point will change the distribution of the gradient relative to the position of the starting color stop. You can see that shifting this anchor point to the left will shift the gradient’s effect so the brightest part is on the left.

Using the Radial gradient will give you an additional anchor point to modify. This will influence how the gradient is distributed.

Note

When you save a gradient, the rotation and position are not saved. You will need to reposition the gradient if you apply it to a different object.

Artwork by Gkoumas George

<http://gkoumas.deviantart.com>

Appendix

To try to keep the book focused, this section includes information and tools that are not directly related to the earlier chapters. While this isn’t information that will directly help you with painting, it will be beneficial if you want to have a deeper understanding of how the application works.

Why Open Source?

One of the reasons that make open source software so attractive is the freedom to modify and share what other people have done. It is the perfect solution to avoid reinventing the wheel. With most paid applications, years of development go into making them good. Many times, the company goes out of business. When they do, thousands of man hours of time and energy are wasted and lost. All of the solutions and problem solving that went into the products are not available for others to build on. This dramatically hinders the evolution of technology.

A Brief History of Krita

At the Linux Kongress conference in 1998, Matthias Ettrich did a presentation to see how easily he could convert some existing code to use a technology called Qt (pronounced “cute”). Ettrich chose to use the graphic application GIMP as a base. The night before the conference, Ettrich wrote 1,100 lines of code that used this newer Qt technology. He took the GIMP code base and showed how it could be converted with little effort. This created disagreements in the GIMP community.

At the time, there was an existing KDE application called Kimage that was started by Matthias Elter. Another individual, Michael Koch, would later name the project KImageShop. Elter became busy with the KDE project, so KImageShop stopped being worked on for a time.

In 2000, John Califf became the new maintainer. His initial enthusiasm and passion for the project resurrected it and put the code base in a good state. In this time, KImageShop changed names again to Krayon. The passion and progress were only temporary, so Krayon lost steam. It was 2001. In the next year, Krayon was not touched.

In 2002, Patrick Julien took over the project. Before he could do much work, Krayon had to be renamed after legal disputes. The name Krita was finally decided upon. Julien continued to work on refactoring the code base. In 2003, Boudewjin Rempt came on board to help development. When Rempt started, Krita was once again in a state of disrepair. Most of the tools were not working at the time.

Since Rempt became the maintainer, the development has picked up considerably. Other developers began to join such as Sven Langkamp, Cyrille Berger, Casper Boemann, Adrian Page, and Michael Thaler.

In 2004, Krita had its first public release after 5 years of development. The press seemed to enjoy this new painting application as well. At this time, Krita was focused on being a generic image editing and painting application.

In 2009, the focus of the application shifted solely to painting. The community also began to establish a development fund to pay developers for their work. The project started participating in the Google Summer of Code program. The Blender Foundation also began using Krita for their preproduction work on Sintel.

In 2013, the Krita Foundation was formed. This foundation was made to provide support for development. The foundation has since used other platforms such as Kickstarter to provide funding.

References

Multi Toolkit Programming: Interoperability of different GUI toolkits for the X Window System

<http://www.linux-kongress.org/1998/abstracts.html>

History

<https://krita.org/about/history/>

The History of KImageShop / Krayon / Krita

<https://krita.org/item/the-history-of-kimageshop-krayon-krita-2/>

Krita Development Cycle

Krita is being developed and improved every day. Even though there are features constantly being added, you might not want every change. New features can create bugs and cause Krita to crash. This could be dangerous if you are counting on the application to be stable.

Applications such as Krita are developed in release cycles. Every version of Krita has a process it follows. This process helps control each new version of Krita so it gets the most features added while trying to make it as stable as possible.

When you look at the splash page when Krita launches, you will see the release type and number under the splash graphic. This will tell you what type of build was done with Krita. A build is when the programmer decides to take all of the code and make a new version of Krita to download.

Spotting what version of Krita you are on: The splash page tells you the version as well as the last code that was added (git number).

Developers do these builds daily when they are adding new features. Sometimes they do a build and share it with everyone on krita.org. Krita uses the following development terminology for each new release.

• Alpha – New features are being added. If someone spots a bug, a developer will fix it. The developers are really concentrating on adding new features, so there will be bugs introduced to the code base. With most applications you use, this version is never released to the public. Krita is open source, so the developers like to share these builds sometimes. The Krita developers will sometimes call this Pre-Alpha.
• Beta – The developers have decided that the next version is feature complete. They are focusing on bugs and fixing any crashes that people might report. These releases are put out by the developers so people can help with testing.
• Release Candidate – The release has been in Beta for some time, and the developers think they have most of the bugs fixed. While fixing all of the bugs would be ideal, this is generally not feasible with time and resource constraints. The developers prioritize the remaining bugs and will fix anything that is major.
• Final Release – Everything looks good to go. There will be small bugs that exist, but they are too minor or too much work to bother with. Blessed by the developers, the Final Release is the best version if you need Krita at its most stable. The developers and website refer to this as the “stable version”.

Krita on the Command Line

In addition to having a graphical user interface to make paintings, the Krita executable is also a command line tool. If you aren’t familiar with command line tools, it is a way to automate common functions. Programmers like these tools since they can create scripts that automate common tasks. This area in Krita is very limited, so there aren’t many functions you can do.

The command line tool can be a helpful way to automate exporting files.

To start using the command line tool, you can add the Krita executable directory to your environmental variables. I added the following value to my PATH variable in Windows: C:\Program Files\Krita (x64)\bin

Once you add the Krita executable path to your environmental variable, you can open up the command prompt and type krita –help. You will get a list of options that are available as shown in the image above.

For a quick example, we are going to open a KRA file and print it. To start, I navigated to the folder that has my KRA files. Open the sphere.kra file, then print it (this will open up the GUI).

krita –print sphere.kra Commands do not give a response if an error happens. If you enjoy working with Krita and would like to expand the command line tool, you can check out the source code. The source code is mostly in the Krita > main.cc and source > calligra > krita > ui folders.

Document Metadata

Some artists like to include metadata with their images. This information can be entered from the main menu File > Document Information. You can add data like the title subject and language. If you share your artwork across the Internet, this information will be kept inside the image. Some image applications use this information to help categorize the images. You can also set your author information in Krita’s preferences.

Memory Performance

If Krita is running slow, you might need to adjust the performance options. Krita uses some pretty smart defaults when it comes to managing memory, but you might have to tweak them. Your computer also might slow down in situations where you change your document dimensions. For example, working on a 512 px x 512 px canvas might be fast, but working on a 6000 px x 6000 px canvas might be slow. There are a couple of areas in Krita where you can view and change your performance settings.

You can view your computer’s performance from the status bar. In the following picture, you can see that a 1500 px x 800 px image will take up 9 MB. If you click on the dimensions in the status bar, a tooltip will appear showing you even more information. The goal of this screen is to help identify how and where Krita is running slowly.

The status bar will help you know if Krita is running slow.

You can access these settings from the main menu by going to Settings > Configure Krita > Performance. Let’s go over each setting in more detail.

Fine-tune Krita’s performance by changing the various settings. Krita will need to be restarted before your changes take effect.

• Memory Limit – How much RAM will be set aside for Krita to use. Setting this value too high can slow down your entire computer, so be careful.
• Internal Pool – An internal setting that allows Krita to allocate a chunk of memory to work with. It is recommended that you set it at the file size of one of your layers. Look at the status bar to determine how much space a layer takes up.
• Swap Undo After – Every time you do an action like applying a filter, Krita stores that information in memory. This data is stored in case you ever want to undo something later. Your undo actions take up a lot of memory, so Krita temporarily stores some of it on your hard drive. This setting will control how big the file size chunks are for undo information.
• File Size Limit – Krita uses your hard drive space for extra RAM. Your computer might not have much RAM, so Krita will need to save some of the information on your computer. This setting determines how much hard drive space Krita is allowed to use for extra RAM.
• Swap File Location – Where on your hard drive the extra RAM will be stored.
• Enable performance logging – Output your performance information to a text file. This is helpful when working with developers. Changing this will not improve your performance.
  For all of these settings, you will need to restart Krita for your changes to take effect. If changing these settings don’t seem to improve Krita’s performance, get in touch with the developers on the forum or chat room.

Finding Older Versions of Krita

On the krita.org Download page, the Krita developers direct people to the latest stable version. This is an easy path, and most people will always want this. The Krita developers also store a history of previous versions of Krita. This can be useful if there is a bug and you need to install an earlier version.

Find and download an older version of Krita.

From the Download page, there will be a link near the top that says http://files.kde.org/krita. You will be taken to another website where you can select your operating system. For Windows, the zip files are self-contained versions. These do not need to be installed. Once downloaded, you can open up the bin folder and click the executable file. This self-contained version makes the application more portable. The msi files are normal installer files that are typical with Windows applications.

Reset the Settings Back to the Default

As you begin to customize Krita, a number of the settings are saved to your computer. This will make sure that Krita remembers everything the next time it is started. This can sometimes create issues when new versions of the program are released. To fix these issues, resetting the configuration file is required. To do this, hold down Ctrl + Alt + Shift before starting Krita. A prompt will appear asking you to clear your kritarc file. If you click Yes, the settings file will be cleared out.

Closing Thoughts

You should now have the tools you need to create great digital artwork. A good tool is not a substitute for artistic training and practice though. Improving as an artist is a lifelong journey. There will always be people better than you and others that are worse. All that you can do is take one step at a time. An application like Krita is just one piece of the puzzle.

I hope you have found this book helpful. I have learned a lot myself and have grown throughout the process. I look forward to seeing your artwork in the future.

Artwork by Cesar

http://cesar-fps.deviantart.com/

Index

About the Author

Scott Petrovic is a user interface designer and developer living in St. Louis, Missouri, U.S.A. Scott is an active member of the Krita development community that manages krita.org as well as makes improvements to the application. Scott received a B.S. in Computer Graphics Technology from Purdue University in 2007. When not contributing to Krita, Scott can be found going to local drawing, video game developer, and website Meetup groups.