Realtime Soft Shadows in Dynamic Scenes

1
Real-time Soft Shadows in Dynamic Scenes using
Spherical Harmonic Exponentiation
MSR, MSRA, DirectX
ray traced
ambient occlusion
SHEXP
approximate blockers as spheres
accumulate low-frequency visibility in SH
g g1g2gm gi vis. of blocker i
g exp(f 1 f 2 f m) f i
log(gi)
(a) product space
(b) log space
use log space to convert expensive product to
cheap add
real-time results