This demo shows: editing parameters of lights, moving the camera, and changing integrator settings.

Video produced by Christos Obretenov of Lollipop Shaders.

Interactive rendering (or "IPR", also called "re-rendering" or "live rendering") uses the progressive refinement mode of path-traced rendering to continually update a render as aspects of a scene are changed. It is, fundamentally, the same as rendering, but all manner of interactive, real-time edits are possible during an IPR session. Rendering of the image is restarted after each edit (returning to a noisy image again), but the renderer keeps the scene loaded and ready to render.

During an interactive rendering session in RenderMan, you can:

• Move the camera and change its parameters
• Add and delete lights
• Change light linking
• Change material bindings and edit material and pattern parameters
• Change integrator and projection bindings and parameters
• Edit geometry attributes

The major restriction is geometry. Geometry cannot be added, deleted, or moved during interactive renders, yet.