[Soc-2011-dev] Weekly progress report #8 - Dynamic Paint

[Miika Hämäläinen]

> 1) what you did this week
I was investigating ways to optimize Dynamic Paint speed, especially 
when using very high resolution surfaces. So far I've done small 
modifications all over the code slightly improving overall performance, 
and up to 50% speedup when painting with random sized particles. An 
extra bounding box check also gives great speedups in situations where 
brush object is nowhere near the surface.

I also experimented with various space partitioning methods to reduce 
need for ray and distance-to-checks (that already use BVH trees) in 
situations where surface is clearly out of brush influence. 
Unfortunately, it seems that generating the octree usually is equally 
slow as checking every single point without it. However, in situations 
where canvas isn't moving and it's possible to use same octree again, 
it's possible to achieve up to 3x speedups.

> 2) what you will do next week
I will keep working on this for one more week to finish current changes 
and check if any further optimization is possible.