Texture-Space Particle Fluid Dynamics

In 2007 shortly before NVIDIA acquired Ageia I was working on an idea of running 2D SPH in UV space on arbitrary meshes. This was to do several things... 1) it allowed me to make a bunch of assumptions that would make surface generation faster and better, and 2) I could easily stain the surface that the particles were moving over which would give the feeling of greater volume and detail.

It was fairly simple to implement, everything was in 2D so I used a world-space normalmap to compute which direction was up for each particle, and sampled a tangent-space normalmap to apply variable friction and modulate the staining function.

This never got beyond weekend experiment status, but I did capture this video at some point to prove the concept kind of worked. Next steps would have been moving particles back and forth between 2D simulation and 3D simulation (so you could say poor water on the floor) and handle UV wrapping.