Each year Pixar tosses a Renderman User’s Group meeting at SIGGRAPH. In the past few years, we’ve invited some of our users to present some of their techniques to a wide audience in a portion of the program we call Stupid RAT (Renderman Artist Tricks). Each year, there seems to be at least one presentation that really captures your attention, and this year the award goes to Hal Bertram and The Interaction Trick.

The trick was actually pretty simple: to use the raytracing capabilities of Renderman (essentially a batch process) in an interactive viewer. It’s brilliant really. Try watching the videos and reading the notes. We are all very impressed.