resizes mapped buffer and leaves new buffer mapped

* Generate a bit set for the particle phase, the group should be an integer < 2^24, and the flags should be a combination of FlexPhase enum values */

returns random number between 0-1

performs Atomic operation on two consecutive fp16 values in the given UAV the uint paramater 'fp16x2Val' is treated as two fp16 values the passed sub-

returns this vector

generate a rotation matrix around an axis, from PBRT p74

3d gradient function.

returns a random unit vector (also can add an offset to generate around an off axis vector)

@OPTIMIZE: binary search

fast floor float->int conversion routine.

like cubic fade but has both first-order and second-order derivatives of 0.0 at [0.0,1.0]