Coloring with bitmap orbit traps, made in 2002 - Click image to enlarge
The image above made it into the first position of the National Fractal Art Contest of 2002 in Spain (click here for the results). The pink-bunny image belongs to Made, the demoscene graphician.
The second idea was to do orbit traps with real distances to the trap. For that to work I made a black and white image with the trap area in black, and then for every white pixel I computed the distance to the closest black pixel. The resulting grey-scale image encoded the 2D distance field that I could use as true replacement for geometric traps in the regular orbit trap algorithm:
The input trap image
Precomputed distance field
An example of basic in/out trap algorithm can be found here: