Tools

random-ellipses

This script generates random grayscale ellipses in a new layer.

The background of the layer is 50% gray, and ellipses contain a linear gradient.

  • In ellipses with a size above average, the gradient goes from 50% gray to white
  • In ellipses with a size below average, the gradient goes from 50% gray to a lighter gray proportional to the ellipse size, e.g. the gradient in a half size ellipse will go from 50% gray to 75% gray. In other words, if the layer is used as a bumpmap, all the ellipses smaller than the average will have a height proportional to their size and produce the same slopes.

When two ellipses overlap, the lighter tone is kept.

Options:

Density

The percent of area covered by ellipes

Overlap

Whether the ellipses can overlap or not.

Average size

The average diameter of the ellipses, in pixels. The ellipse flattening is done while preserving the ellipse area, so this value is the geometrical mean of the two diameters of the average ellipse.

Size variability

The variability of the ellipse size, which is the spread of a log-normal distribution.

  • When 0, all ellipses will have the same size.
  • When 10, ellipses produced will usually range from one third to three times the average.
Average flattening

The average flattening of the ellipses, in percent.

  • 0 is a perfect circle.
  • 90 is a very flat ellipse
Flattening variability

The variability of the ellipse flattening, which is the spread of a gaussian distribution.

  • When 0, all ellipses will have the same flattening.
  • When 10, the flattening values between 0 and .9 are about equiprobable.
Average tilt

The average tilt of the ellipses from the horizontal, in degrees.

Tilt variability

The variability of the tilt, which is the spread of a gaussian distribution.

  • When 0, all ellipses will have the same tilt.
  • When 10, all tilt angles are about equiprobable.

Usage notes

The output of this script should be seen as a map, that can receive further transformation

  • Threshold to replace gradients by more "binary" values
  • Curves, to chnage the shape of the gradients

There are many ways to use the output:

  • Bump map
  • Displacement map
  • Color map
  • Alpha channel

density-brush-fill

Fills a new layer with random strokes of the current brush until the required density is reached.

Options:

Density

The percent of area covered, alpha-weighed

Usage notes

The output of this script is a new layer overlapping the current layer.

If the brush is an image pipe, the various images are used as designed

autocrop-linked-layers

Autocrops all linked layers in the image. It appears as Image/Autocrop linked layers and has no parameters.

clear-layers

Deletes the selection in several layers. Edit/Clear layers/All affects all layers, while Edit/Clear layers/Visible only affects visible layers. There are no parameters.

interleave-layers

This script creates an image by interleaving layers in a stack of layers. The inserted layers can come from another stack of layers, or can be duplicates of a single layer. The inserted layers can be merged into the matching layers with a given transparency and layer mode. This can be used to blend two animations.

The base layers come from the current image (the one through which the script is called)

In multiple-layer mode, the inserted layers come from another image already loaded in Gimp, as specified in the script parameters dialog.

In single layer mode, the inserted layer can come from any loaded image (including the one used as a source for the base layers)

The two images or the image and the layer should have the same size, and for multiple-layer both stacks should hold the same number of layers

Only visible layers of both images are used, so work layers can be left out by making them invisible.

The script is started by the Image/Interleave multiple layers... or Image/Interleave single layer... menu.

Options:

Layers source (multiple-layer mode)

The image from which the inserted layers are obtained.

Layer (single-layer mode)

The layer which is interleaved with the base layers.

Opacity

An opacity to be applied to all inserted layers.

Mode

A layer mode to be applied to all inserted layers.

Merge

If true, the inserted layers are directly merged into the matching base layers, using the specified opacity and layer mode.