How to manage your GIMP brushes

Managing brushes in GIMP can be challenging on many levels. In this article, I am going to show you a simple workflow that makes managing brushes easy and efficient, without the need to resort to a plugin.

First, we'll dive into custom brushes: what they are and what they are used for. We'll look at how GIMP manages custom brushes, the application limitations, and the problems you're likely to run into if you need a lot of brushes. If you don't care about the context and explanations, you can jump straight to the recipe here.

What is a GIMP brush?

In GIMP, as in Photoshop, a brush is a tool modifier that alters

1. the pattern that will be applied to the active canvas, and
2. the behavior of that pattern relative to the position and movement of the pointer.

Choosing a brush is akin to selecting a physical paintbrush while working on a canvas. A paintbrush with a tiny, hard tip will allow you to draw precise thin lines, whereas a different paintbrush with a fat and soft tip will spread the colored ink loosely along its path and will draw a much thicker line. In short: a brush selection determines the size, the shape, and the general properties of the paintbrush or crayon you'll be using to spread paint on the canvas. The brush selection affects the shape, the weight (thickness), and the texture of the lines or shapes you'll be painting with.

In GIMP, brushes are available with the following 3 tools: the pencil, the paintbrush, and the airbrush. The result of applying a brush with either of these tools depends in no small part on the tool itself. If a brush is attached to a pencil, the resulting path will have hard edges and virtually no spread beside that which is defined by the brush's shape and size. This is because just like in its real-world counterpart, the pencil tool is meant for precise stroke, with little to no color bleed around the edges of the line being drawn. If the same brush is attached to a paintbrush, the resulting path will have softer edges, and the colors gradually blend with their surrounding.

When applied using the airbrush tool, the brush's path will spread wide and somewhat randomly around the path's edges. Since the tool mimics spray-painting in the real world, the resulting path's density and opacity will depend on how long the tool was applied for and how hard the trigger was pressed. As you probably figured out by now, the pencil, paintbrush, and airbrush tools mimic in the digital space the behavior and characteristics of their physical counterparts.

There are two general types of GIMP brush: the standard brush tip, which determines the visual properties of linear strokes, and the stamp brush, which is meant to be used for spot prints. Stamp brushes hold complete images and are typically cast to the canvas in a single strike. For example, you could use a stamp brush to apply snowflakes of various sizes and shapes on a layer over a photo.

Stamp brushes can also be used to fill an entire layer or selection area with a complex pattern or texture in a single click. In the real world, stamps are flat casts that transfer ink or paint to the canvas or paper in a single action. You can, for instance, store entire background images in a brush and use the brush to apply backgrounds

The problems with brushes

Find your brushes

The GIMP application does not provide visual management functionality for brushes beyond basic selection. It does not provide a way to add and remove, or enable/disable custom brushes interactively. The only way to add a new brush file to GIMP is to add said brush directly to the brushes folder.

The first step is to locate the brushes folder. The brushes folder will be located somewhere inside the config folder of your GIMP installation. Since this folder is where GIMP expects to find custom brush files, it will be empty by default -- that is: unless you've already added custom brushes to the system.

Note that the exact path to the brushes folder depends on a combination of factors, namely:

1. the operating system,
2. the version of GIMP, and
3. the specifics of the installation.

How to locate your Brushes folder

To locate the GIMP brushes folder,

1. go to Edit > Preferences
2. expand the last item, named Folders
3. click on Brushes (the first item)
4. the location you're looking for appears on the right-side panel: it's the one marked as "writable".

Here's a tip: once you have located the brushes folder, create a shortcut (symlink) and save the latter where you'll be able to find it logically, as you're quite likely to need it again.  This shortcut will make your life easier in the longer run.

What Files?

GIMP can load brush files in the native .gih, .gbr, .vbr or .myb formats, as well as those stored in the .abr (Photoshop) format. Note that brush files can (and usually do) contain more than one brush. As a result, brush files can be quite large. This is especially noticeable if the brushes are made of large and complex images meant to be used as stamps.

Let's keep it real: in most cases, users don't require a wide variety of custom brushes on a regular basis. In fact, for the majority of GIMP users, custom brushes are seldom used, if at all. For normal photo retouching or basic, paint-style work on a canvas, the default brushes supplied by the base GIMP installation are sufficient. The use of custom brushes is a relatively advanced skill. However, custom and stamp brushes can be a useful time-saver when the task at hand calls for it.

You can acquire custom brushes from a number of sources. A simple search for "GIMP brushes" or "Photoshop brushes" will return dozens of potential sources for interesting custom brushes, many of them free. There are also plenty of brush collections available commercially from different artists. The latter are typically better organized and documented.

Resource hog

As mentioned above, GIMP doesn't provide for managing custom brushes within the application. Custom brushes clog the brush panel and tend to make it difficult to select the right brush. Besides, brushes are resource hogs: custom brushes are kept in the application's memory, taking up precious space and slowing down the processes. Given enough custom brushes, GIMP will refuse to load. Ideally, you should keep the number of custom brushes to a minimum, and then only load the brushes you need when they are needed.

The Method

Here's the best way we found to manage your custom brushes in GIMP, without resorting to a resources management extension.

1. Create a shortcut (symlink) to your GIMP brushes folder. This folder is empty by default -- unless you already used it to store custom brushes. Place the shortcut where you can find it quickly and logically. This little step will save you time in the future.
2. Create a hidden folder inside the GIMP brushes folder and name this new folder .disabled. The dot prefix will automatically hide the folder in Linux; if you are working with Windows, you will need to check the hidden flag in the folder's properties list. The goal of this hidden folder is to store your custom brush library. A hidden folder will prevent GIMP from loading the brush files it contains -- hence the name of the folder.
3. Organize your brush collection by logical categories named after their purpose or style by creating a folder for each.
4. Move the relevant brush files into the corresponding folders. GIMP will automatically assign the name of these folders to a filtering tag.
5. When working on a project that requires custom brushes, move the relevant folders out of the .disabled folder and back into the parent brushes folder. If necessary, hit the refresh button in the brush panel.
6. Once you're done with the brushes or when working on a different project, clean up the workspace by moving the brushes back into the .disabled folder.