Plug-In Coloring (Gradient, Direct)
Plug-In Coloring is a skeleton coloring algorithm that lets a coloring plug-in do the actual work. All coloring algorithms in Standard.ucl are also implemented as coloring plug-ins. You can select any of these as the coloring plug-in to be used together with Plug-In Coloring.
There are two versions of Plug-In Coloring: a gradient version and a direct version. Plug-In Coloring (Gradient) is a normal coloring algorithm and works only with gradient coloring plug-ins which return an index into the gradient.
Plug-In Coloring (Direct) is a direct coloring algorithm and works with coloring plug-ins that directly return a color. It also works with gradient coloring plug-ins, but in that case changes to the gradient trigger an unnecessary recalculation.
The Coloring Algorithm parameter sets the coloring plug-in to be used. By default, the Smooth (Mandelbrot) plug-in from Standard.ulb is selected for Plug-In Coloring (Gradient), while Plug-In Coloring (Direct) defaults to the Direct Orbit Traps plug-in.
An example of using Plug-In Coloring is given in Example 2 – Orbit trap plug-ins.