[femto]

I can see the fascination of this problem. There are so many ways to approach it, from addressing the physics, to higher level attempts to get the right look. Searching around, it seems to have justifiably caught the imagination of many.

Here's another approach, made interesting by its use the connection machine [1], whereby an attempt is made to simulate the diffusion of pigments though paper.

[1] https://pdfs.semanticscholar.org/72ab/54ecaaf7458853bd441b94...

[tylerhobbs]

Great comment! Yes, there are many other approaches that are more true to reality, to the point where they are fairly thorough simulations of physics. My approach is somewhat like a five minute figure drawing sketch compared to the equivalent of hyper-realistic 100 hour paintings. Neither is necessarily a better approach, but both are good for different goals. What I like about my approach is that it is very easy for me to understand and manipulate. I can take advantage of this to make new effects that are less like reality but still intriguing in their own way.