Per ray step modulations ? Tweet

[mattwilsonvel]

Hello!

Has anyone considered a ray expression utility that would allow editing of material properties per segment (for example)... particularly with volumes. This has been very helpful in production in the past, but now that it's available in Blender Cycles as well as Karma in XPU mode. It has been quite revolutionary in the rendering of large volumes (like cloudscapes). It also can dramatically decrease render times in cases where the typical solution would require 50 or more bounces. I have had some wonderful results rendering clouds in Octane in the past, and have for years, but my large final frames were often hundreds of hours (granted that is at 12k or larger). Im finding similar or better visual results (particularly being able to modulate phase per step) at a fraction of those older render times.

I posted a sample of the materialX implementation in solaris/karma as a demo scene (https://www.bunnylever.io/learning) if anyone is interested in the comparison. The blender recipe is essentially the exact same and while less stable on overlapping VDBs is 5-10 times faster in most cases.

thanks for all the great software!