ARNOLD render supplies very flexible APIs for MIS(Multiple Importance Sampling) which is an important and classical sampling method to sample both BRDF and light source. MIS has been involved into offline production recently, at the same time, PBR is an unavoidable trend to everyone.
I strongly insist you to read Eric Veach’s Ph.d thesis “Robust Monte Carlo Methods for Light Transport Simulation”, it detailes the Monte Carlo Ray Tracing. And don’t forget the “IS for Production Rendering”, that’s also a good start.
These images were produced by MtoA 0.10.1 on E5200 2 Cores 2.5GHz, sampling configuration is “10/2/2/-1”. There are blender monkey model with CC subd = 2, and an Ambient Light attached with aiSkyDoomLight node.
You can DOWNLOAD the all following images in OpenEXR at 1k x 1k.
- Ashikhmin-Shirley
roughness = 4, 9:28
roughness = 64, 9:34
roughness = 512, 8:58
- Cook-Torrance
roughness = 0.05, 9:16
roughness = 0.55 8:40
roughness = 1.0 8:31
- Scretched-Phong
exponent = 4, 11:53
exponent = 256, 9:35
exponent = 1024, 8:44
- Ward-Duer
roughness = 0.05, 12:39
roughness = 0.55, 10:40
roughness = 1.0, 8:29
