Simple Still Life with BidirVM
Posted: Sun Oct 23, 2022 7:25 am
Hey all, I noticed some forum threads mentioning that LuxCore is no longer under active development, so I decided to put together a scene using LuxCore's bidirectional path tracing with vertex merging (BidirVM) for old times' sake 
BidirVM is one of LuxCore's lesser-known features and was never shown in the addon, however it can be enabled by tweaking a few lines in BlendLuxCore. It works best when supplemented with metropolis light transport (MLT). Why use BidirVM+MLT for this scene?
Each image took an average of 2.5 hours to render on 128 threads at 1920x1536 to 10,000 samples per pixel. Best of luck to all the LuxCore devs in the future 
- Three variants: the left two show SDS caustics.
- And again, in color.
- I used a smoke simulation and heterogenous volume setup for whole-scene atmospheric scattering. This is extremely computationally expensive, and makes denoising impractical.
- Reflective and refractive caustics are created by the highly specular vase, glasses, and a glass block window in front of the light source (for the left two images).
- SDS paths! Bidirectional and simple path tracing cannot reasonably converge SDS paths, even supplemented with metropolis light transport.
- Check out that memory usage!