We briefly discussed tool presets earlier in the chapter, but let’s take a closer look at them now. Tool presets are a new feature of version 2.8, and they are especially powerful when combined with brushes and paint dynamics.
Figure 15-109 (inspired by Ramón Miranda) shows how tool presets, brushes, and paint dynamics interact. In the Paintbrush’s tool options dialog (1), click the DYNAMICS button (2) to open a temporary menu of the available paint dynamics. From this menu, you can select the dynamic you want or click the button in the bottom-right corner to open the Paint Dynamics dialog (3). In this dialog, you can use the tag field only to select the dynamics of some category, here FX
. You cannot edit the settings of a predefined dynamic like Confetti
, but you can edit a copy of it by pressing the button labeled (4) in the Paintbrush tool options dialog. This opens the Paint Dynamics Editor (5).
In Figure 15-109, the Paint Dynamics Editor dialog appears twice. The top copy (5) shows the Mapping matrix (6) for the chosen dynamic. In this example, you see a checked box at the intersection of the SIZE row and the RANDOM column. When you display the SIZE parameters in the Paint Dynamics Editor (7), you see that the corresponding answer curve is not linear at all.
If you’re satisfied with your current settings for the Paintbrush tool and want to save them, click the bottom-left button in the Paintbrush tool options dialog to open the Tool Preset Editor (8). Here, you can choose the name of the new tool preset and its icon. If you click the suggested icon, you get a list of the many icons available, the same as in Figure 9-54. More important, you can choose what settings to save. In this example, the current foreground and background colors are not saved because the colors are selected at random in the chosen gradient. The current brush, dynamics, and gradient are saved because they are fundamental to this FX Confetti
preset. Finally, the current pattern, palette, and font are irrelevant with the Paintbrush tool.
The Tool Presets dialog (9) is opened by selecting Image: Windows > Dockable Dialogs > Tool Presets. You can also open the Tool Preset Editor by clicking the first button in the bottom row of the Tool Presets dialog.
As you’ve seen, GIMP comes with 17 predefined paint dynamics. The Basic category contains seven dynamics:
Basic Simple
links Opacity to Pressure and Angle to Random in the Mapping matrix of the Paint Dynamics Editor, which means that for a round brush, only opacity varies. The Angle-Random answer curve begins in the middle of the square, so the angle changes even if random is null.
Dynamics Random
links Size to Random.
Negative Size Pressure
has the same settings as Basic Simple
, plus a link from Size to Pressure, with an inverted linear answer curve, which makes the drawing more transparent when you press more on the stylus.
Pencil Generic
is a complex dynamic that links Opacity to Pressure and Velocity (steep answer curve), Size to Pressure (concave answer curve), Angle to Direction, Force to Pressure, and Jitter to Pressure and Velocity (concave answer curve).
Pencil Shader
has the same settings as Basic Simple
. Only the answer curves are different: Opacity-Pressure is steeper in the middle, and Angle-Random is simply linear.
Pen Generic
links Opacity to Pressure, Velocity, and Fade; Size to Pressure and Velocity; and Angle to Random. The Size-Pressure answer curve is almost linear up to the middle and then decreases to zero for the maximum pressure. The Size-Velocity curve is concave.
Pressure Opacity
links Opacity to Pressure, first with a concave and then a convex answer curve.
The FX category contains three Paint Dynamics:
Confetti
is a complex dynamic, with Size, Angle, and Color linked to Random, and Hardness and Aspect ratio linked to Pressure. The Angle-Random answer curve is linear and begins in the middle.
Perspective
links Opacity and Aspect ratio to Pressure and links Angle to Direction. All the curves are linear.
Speed Size Opacity
links Opacity to Pressure, Size to Pressure and Velocity, and Angle to Direction.
Finally, seven dynamics have no category. Their answer curves are linear unless otherwise noted:
Basic Dynamics
links Opacity to Pressure and Fade, Size to Velocity, and Angle to Tilt. This dynamic is the most natural for simple painting.
Dynamics Off
has an empty mapping matrix. Select this dynamic when you want no effect at all.
Fade Tapering
links Opacity and Size to Fade.
Random Color
links Color to Random.
Tilt Angle
links Angle to Tilt and is useful only with a tablet that records the pen tilt.
Track Direction
links Angle to Direction.
Velocity Tapering
links Opacity and Size to Velocity.
You can extend this set of paint dynamics as needed. Use the predefined dynamics as models. Avoid defining a dynamic with too many checked boxes in its mapping matrix because its behavior will be difficult to predict.
Several of the predefined paint dynamics are especially handy when combined with some predefined tool presets, as you’ll see in Predefined Tool Presets.
As already mentioned, GIMP’s 54 predefined brushes are divided according to their tags: Basic
, Media
, Sketch
, Splatters
, Texture
, and Legacy
(Figure 15-110 to Figure 15-115) .
You can define your own brushes, as detailed in 22.4 Building New Brushes. Any brushes you’ve created are listed first in the Brushes dialog, followed by the predefined brushes, which are listed in alphabetical order. A brush’s appearance in the list depends on its tag filter at the top of the dialog. Remember that when no tag is specified, the first brush in the dialog is the contents of the clipboard cropped to a maximum size of 512 × 512.
A wide variety of brushes is available on the Web at, for example, http://www.noupe.com/how-tos/1000-free-high-resolution-gimp-brushes.html and http://www.pgd-design.com/gimp/br.php. The Gimp Paint Studio (http://code.google.com/p/gps-gimp-paint-studio/) offers a large collection of brushes specifically designed for GIMP.
Brushes designed for Photoshop can also be used in GIMP. Simply place the downloaded brushes into you GIMP’s brushes folder, and refresh the Brushes dialog by pressing the button at the bottom.
GIMP now contains 29 predefined tool presets, divided into 4 categories.
FX contains eight presets (top left of Figure 15-116):
Crop 16:9
crops in a 16:9 ratio.
Crop Composition
applies the Crop tool without any setting other than HIGHLIGHT and RULE OF THIRDS.
Fill Paper (Multiply! Sel. Pattern)
opens the Bucket Fill tool in Multiply mode, selecting the Paper
pattern (Figure 15-117) with an opacity of 50%.
FX Confetti
opens the Paintbrush tool with the 1.Pixel
brush, the Confetti
paint dynamics, the Tropical Colors
gradient, and a significant jitter (Figure 15-118).
FX Radial Softlight
applies the Blend tool with the FG to Transparent
gradient in SOFT LIGHT mode and a RADIAL shape. You can choose the foreground color. From Figure 15-119, we achieved Figure 15-120 by choosing a bright green for the foreground color and placing the center of the gradient on the sun.
Glow Lights (Addition!)
opens the Paintbrush tool at 40% opacity and in ADDITION mode, using the Hardness 050
brush and the Pressure Opacity
paint dynamics. The brush size is set to 400, and the INCREMENTAL box is checked. For example, if we take Figure 15-121, we can get Figure 15-122 by choosing a bright green color and drawing across the image with increasing pressure.
Smooth Clone (Press Ctrl)
opens the Clone tool with all default options, except SIZE set to 150, the Dynamics Off
paint dynamics, and the SAMPLE MERGED box checked. Choose your brush, preferably Hardness 075
or Hardness 050
, and begin cloning.
Vignette
opens the Blend tool in MULTIPLY mode at 75% opacity, using the FG to BG (RGB)
gradient, a RADIAL shape with an OFFSET of 25, and the DITHERING box checked. It simulates the so-called vignette effect produced by old-time, low-value cameras.
Paint contains 13 presets. All these presets but the last two use the Pressure Opacity
paint dynamics. These tool presets differ in terms of the tool and brush they apply and the various tool options settings mentioned next. They constitute a set of daily tools with carefully chosen characteristics ideal for painters.
Airbrush
uses the Hardness 050
brush with a SIZE of 500 and sets RATE to 30 and FLOW to 10.
Basic Knife
applies the Paintbrush tool (as do the next three presets) with the Block 03
brush and a SIZE of 180.
Basic Round
uses the Hardness 100
brush with a SIZE of 80.
Basic Round Detail
uses the Hardness 075
brush with a SIZE of 20.
Bristles
uses the Bristles 01
brush with a SIZE of 60. This tool simulates drawing as if with an old toothbrush.
Eraser Hard
uses the Block 01
brush with a size of 80 to erase with a strong square eraser.
Noise
uses the Paintbrush tool with the Sponge 01
brush with a size of 450 and an ANGLE of 90, which is meaningful only if you change the ASPECT RATIO.
Smudge Rough
uses the Acrylic 01
brush with an OPACITY of 50 and a SIZE of 100, with the RATE set to 60.
Smudge Soft
is the same as Smudge Rough
, except it uses the Hardness 050
brush.
Soft Oil Brush
and the next three presets use the Paintbrush tool. Soft Oil Brush
applies the Oils 02
brush with a SIZE of 80. It simulates painting with oil paint.
Splatters
applies the Splats 01
dynamic brush with a SIZE of 200. It simulates the result of shaking your brush above your canvas.
Perspective
applies the Structure
brush with a SIZE of 283.55, using the Perspective
Paint Dynamics. Use this preset to draw strokes that follow the shapes of forms on the canvas.
Vegetation
applies the Vegetation 02
dynamic brush with a SIZE of 250 and the Pressure Opacity
paint dynamics (Figure 15-123).
Selection contains two presets, handy for two common situations. Use these presets to generate your own ideas for defining presets:
Circle 200px
creates a circular selection with a diameter of 200 pixels. The ANTIALIASING box is checked.
Feathered Selection
opens the Rectangle Select tool with the ANTIALIASING, FEATHER EDGES (RADIUS set to 25), and ROUNDED CORNERS (RADIUS set to 50) boxes checked. The guides are set to CENTER LINES.
Sketch contains six presets, similar to the Paint presets:
Blue Pen (Multiply)
applies the Paintbrush tool in MULTIPLY mode with OPACITY set to 75%, the Hardness 075
brush at SIZE 15, and the Pen Generic
paint dynamics. The foreground color is set to (26, 47, 152) RGB, that is, a dark blue. The result simulates a sketch made with a blue ballpoint pen (Figure 15-124).
Eraser Soft
is the same as Eraser Hard
, but it uses the Hardness 050
brush.
Ink Smooth
applies the Ink tool with SMOOTH STROKE checked, QUALITY set to 75, WEIGHT to 300, ADJUSTMENT SIZE to 10, TILT to 0, and SPEED to 0.9. The tip is a round size, deformed as a narrow oval tilted to the right. These settings are good for calligraphy.
Ink Thin
applies the Ink tool with ANGLE set to 0.5 and SPEED to 1. The tip shape is a simple round size. This preset is good for simulating handwriting.
Pencil
opens the Paintbrush tool with OPACITY set to 50%, the Pencil 01
brush set to a SIZE of 50, and the Pencil Generic
paint dynamics. APPLY JITTER (AMOUNT set to 0.2) and INCREMENTAL are checked. This preset simulates using a soft pencil on drawing paper.
Pencil Soft
has the same settings, except the Charcoal 02
brush is set at a SIZE of 200. It simulates using a charcoal pencil.
By experimenting with this set of predefined tool presets, you’ll get ideas for defining your own tool presets. Don’t forget to tag them, too, so you can retrieve them easily. You can use existing tags, but you can also invent new ones, and you can apply several tags to the same object. Defining a new tool preset is much easier than defining a new brush. And, of course, if you miss a specific paint dynamics, you can easily define it as a tool preset. Figure 15-125 to Figure 15-127 show a few examples of work that combines custom predefined brushes, paint dynamics, and tool presets, courtesy of Ramón Miranda, the main author of the GIMP Paint Studio (see http://code.google.com/p/gps-gimp-paint-studio/). GIMP Paint Studio offers a huge collection of brushes and presets designed to speed up repetitive tasks by minimizing the need to reset tool options manually when changing tools. Its main goal is to support painting tasks, as its name implies.