Hi gang,

I've gotta get to class in a few minutes, but, here's something to look at:

http://www.ibiblio.org/propaganda/Gimp-DiseaseFilter.gif

Disclaimer: I don't know if this sort of thing already exists in Gimp. If it does, do let me know. It would save me alot of coding effort. :)

Basically, "Disease" can be thought of as a hex map where three factors (radial dispersion, cell resistance and viability) determine pixel behavior. If apply this idea to the canvas, you effectively have the ability to dictate the "texture" of the paper, so to speak.. Or, if used as a mask, it can express varying degrees of color permiability in an image beneath it.

This filter uses disease transmission as a model--Cell A is "infected" with paint, and A's neighboring cells similarly become infected based on user-specified values of radial dispersion, cell resistance, and viability for each color channel. For example, if we consider the whole "color permiability" angle where we're toying with the canvas---if we changed the radial dispersion in the diagram to something like (sin(1/x^2)) and made x equal to (R+(G*0.8)), this would cause a few waves of varying yellow-brown permiability originating from point A...Coffee stains, basically.

More later, when I have the time. :(

Cheers, Bowie