[Soc-2011-dev] Weekly progress report #11 - Dynamic Paint

[Miika Hämäläinen]

> 1) what you did this week
This week I finished my last weeks velocity based Dynamic Paint features. Smudge tool turned out to be harder to implement than I first thought, but I eventually managed to get it to work quite nicely. While finishing and testing those changes, I ran into other issues with existing "drip effect". So rest of the week went quite much on fixing bugs and doing smaller improvements.

Two smudge brush demo videos:
http://www.youtube.com/watch?v=W0RABApAA_g
http://www.youtube.com/watch?v=daJll9Do-bw

Complete commit log for this week:
* Object velocity can now be used to determine brush influence and color.
* Brushes can now be set to "smudge" existing paint.
* Added new operators to easily add and remove surface output mesh data layers from Dynamic Paint ui.
* Fixed drip effect algorithm to work properly on forces pointing towards surface.
* Adjusted drip effect speed.
* Drip effect can now use canvas velocity and acceleration to influence drip direction.
* Fixed texture mapping for material enabled brushes.
* "Object Center" type brushes can now use "material color" as well.
* Improved surface partitioning grid generation algorithm.
* Fixed possible invalid brush collision detection when OpenMP enabled.
* Fixed incorrect random sized particle displace/wave influence.
* Fixed "Object Center" brush color ramp falloff.
* Fixed invalid zero alpha sampling when rendering vertex colors.
* Smudge now works properly with substeps.
* Velocity brush speed clamping now works for all brush types.
* Small tweaking on velocity brush ui.
* Added a new "color spread" slider for "spread" effect to adjust how much colors get mixed.
* Improved smudge behavior on "wet" paint.
* Displace can now be set "incremental". This way it's added on top of previous displace.
* Added "displace clamp" setting. You can use it to limit maximum amount of displace.
* Fix: velocity data wasn't always initialized, this could lead to no effect at all or crash.
* Fix: Vertex color rendering near zero alpha values was still incorrect.
* Lots of smaller tweaking.

> 2) what you will do next week
I'm planning to dedicate next week for documentation. This includes at least updating my existing Dynamic Paint tutorials and wiki.b.o page.