Archive for August, 2009

RSL Surface & Spotlight

Wednesday, August 19th, 2009

9/23 – Fixed a bug with the way I summed the diffuse illumination in my Surface Shader
8/26 – Surface Shader now uses Oren Nayar diffuse.

AW Surface

This is an all-around surface shader with lots of different outputs. It was designed as an integral part of my shading pipeline using Houdini. For the time being it's partner's are aw_spotlight and aw_prman_envlight. By using specific categories and message passing techniques they make a good basis for shading in Houdini with prman.


  • Blinn Specular
  • Rim Light
  • sRGB decoding for all texture maps
  • Image transparency for texture map
  • Alpha matting over background color
  • Bump map
  • Reflection with or without environment map
  • Distance based falloff for reflections
  • Weighting reflections by glancing angles
  • Bake out pointcloud for illumination data
  • Read in a pointcloud for illumination data
  • AOV's for everything, but this assumes you are using my env light and/or spotlight

AW Spotlight

This is a spotlight shader with a lot of nice controls. It was built to split up normal light output, attenuation and shadows as three components. This makes it possible to output diffuse only passes without shadows, and a nice shadow pass.


  • Depth map + Deep Shadows
  • Transmission (ray traced) Shadows
  • utilities for inverting shadows
  • Outputs shadows, non-shadow and attenuation
  • Quadratic and Cubic falloff

This is an example render showing a transmission based shadow AOV.

Both downloads are below.

Download:AW Surface Shader
Download:AW Spotlight