5.9. Symmetry Painting dialog

Symmetry Painting is a new painting feature in GIMP-2.10, supported by brush-based tools (Pencil, Paintbrush, Eraser, Airbrush, MyPaint brush, Clone, Smudge, Dodge) as well the Ink tool. There are several kinds of symmetry, all configurable.

5.9.1. Activating the Dialog

You can access this dialog from the image Menu bar through: WindowsDockable DialogsSymmetry Painting

The dialog Symmetry Painting is dockable. Read Paragraaf 2.3, “Koppelen van dialoogvensters” to learn more about the concept of dockability.

5.9.2. Using the Symmetry Painting dialog

Figuur 15.84. Symmetry Painting dialog

Symmetry Painting dialog

This dialog is very simple. You only have a Symmetry item with a drop down list that offers four options. As soon as you check a symmetry type, symmetry axes appear as dotted green lines in the image window and you can start painting with the brush you have chosen.

Options

none

That is the default option; the symmetry painting is not activated.

Mirror

Figuur 15.85. The Symmetry mirror dialog

The Symmetry mirror dialog

This is a symmetry like in a mirror. You can select an Horizontal symmetry, a Vertical symmetry or a Central symmetry. You can also select several symmetries.

The default position for symmetry axis is the middle of the image window. You can place axis where you want using Horizontal axis position and Vertical axis position.

Disable brush transform: when you transform the drawing, the brush itself will end up transformed as well. For instance, in a mirror transform, not only will your drawing on the right of the canvas be mirrored on the left, but the brush itself is obviously "flipped" on the left. If for some reason, you want the drawn lines to be mirrored (or other transformation) but not the brush outline itself, you can check this box. For obvious reason, you won't see it with symmetrical brushes though. That's why you don't see the effect since many default brushes are symmetrical.

Tiling

Tiling is a translational symmetry, which can be finite (with a maximum of strokes) or infinite. In the latter case, it is the perfect tool to create patterns or seamless tiles, at painting time.

Figuur 15.86. The Symmetry Tiling Dialog

The Symmetry Tiling Dialog

This mode covers the image with strokes.

No axes here. The options are:

  • Interval XInterval Y: these are the intervals on X and Y axis, in pixels, between stroke centers.

  • Shift: this the shift between lines on the X axis, in pixels.

  • Max strokes X, Max strokes Y: these are the maximal number of brush strokes on X and Y axis. Default is 0, which means no limit, according to the image size.

Mandala

Figuur 15.87. The Symmetry Mandala Dialog

The Symmetry Mandala Dialog

Strokes are placed around the center of coordinates of axis.

The options are:

  • Center abscissa, Center ordinate to position the center of coordinates.

  • Number of points: number of strokes.

  • Disable brush transform: see above.

5.9.3. Examples

Pepper brush is selected. Pencil is used.

Example for Mirror

Figuur 15.88. Vertical Symmetry

Vertical Symmetry

A single click

Vertical Symmetry

A stroke


Example for Tiling

Figuur 15.89.

A single click. Shift = 20.

A stroke


Example for Mandala

Figuur 15.90.

A single click

A stroke