Summary:
Uses some magic pseudo-random which is actually a
texture coordinate hashing function.
TODOs:
- Dither noise is the same for all the frames.
- It's different from Floyd's dither we've been
using before.
- Currently CPU and GPU dithering used different
implementation. Ideally we need to use the same
dither in CPU.
Reviewers: brecht
Reviewed By: brecht
Differential Revision: http://developer.blender.org/D58