Description:

GD::Icons generates an arbitrary number of icons that vary by shape, color
and color intensity. This is intended to be used in cases for which a
series of related icons are needed. For example, if you want to generate
icons to represent traffic congestion on a geographical map, you can
generate icons having shape of the icon represent the cause of congestion
(accident, flooding and construction) and the color of the icon to
represent the severity of the congestion (e.g. red for severe and blue for
not severe congestion). In addition to these two dimensions of coding
(shape and color) you can use a third dimension, intensity of color.