3.16. Smudge

Figure 14.103. Smudge tool

Smudge tool

The Smudge tool evokes finger painting . With GIMP-2.10, it works in two ways:

3.16.1. Activating the Tool

You can find the Smudge tool in various ways :

  • through ToolsPaint ToolsSmudge in the image menu,

  • by clicking on the tool icon: in Toolbox,

  • or by pressing the S key on keyboard.

3.16.2. Key modifiers (Defaults)


The Shift key places the smudge tool into straight line mode. Holding Shift while clicking the mouse Left Button will smudge in a straight line. Consecutive clicks will continue smudging in straight lines that originate from the end of the last line.

Figure 14.104. Smudge tool

Smudge tool

Shift click and drag to create line


Using Ctrl with Shift, you can constrain the angle between two successive lines to vary by steps of 15°.

3.16.3. Options

Figure 14.105. Smudge Options

Smudge Options

Normally, tool options are displayed in a window attached under the Toolbox as soon as you activate a tool. If they are not, you can access them from the image menu bar through WindowsDockable WindowsTool Options which opens the option window of the selected tool.

Opacity; Brush; Size; Aspect ratio; Angle; Spacing; Hardness; Force; Dynamics; Dynamics Options; Apply Jitter; Smooth stroke; Lock brush size to zoom; Hard edge
See the Common Paint Tool Options for a description of tool options that apply to many or all paint tools.

This option could be called "Smudge length" since it sets the length of the smudging effect in a stroke.

Figure 14.106. Rate example

Rate example

1: Rate=20 2: Rate=60 3: Rate=90

No erasing effect

If smudging will decrease alpha of some pixels; this alpha is not decreased if this option is checked, and so pixels are not erased. This is useful to fill a gap between two color areas.

Figure 14.107. An example of "No erasing" from the programmer

An example of "No erasing" from the programmer


We already saw the different behavior of the Flow option when it is set to 0.00 (works as the original Smudge tool) and set to more than 0.00 (uses the foreground color for smudging).

No erasing effect and Flow are new options in GIMP-2.10. Here are comments and examples from the programmer of these options in gimp-forum.net: