The core of the issue is that there are backfacing interpolated normals, NdotL and/or NdotV end up being negative for them.
Things we tried:
1. Explicitly using geometry normals for some things. Doesn't really work that well.
2. Clamping NdotX to some small value instead of just ignoring light contribution. Works better, but there are still some artifacts.
1. Probabilistically let ray through material or reflect it based on
transparency probability (which is essentially just alpha for now).
2. Introduce opaque flag to be able to treat transparent objects as not
casting shadows. This is not very realistic, but oh well.
on amd gpus it won't draw anything at all unless you have the entire ray tracing pipeline set up fully and correctly:
- have at least rgen, rmiss and rchit shaders
- set up shader groups to reference them
- set up sbt to reference shader groups
it is not enough to just have a single rgen shader operating like a compute shader. amd will have a shader preamble that checks for something and exit early w/o actually running any shader code you wrote
meh
