Bidirectional Path Tracing implemented in Python, relying heavily on Numba for performance. This is a work in progress and may be unstable, incorrect, etc. especailly as I'm just getting started with it. Performance is, well, poor. But for single-threaded, cpu-only, it's actually pretty decent. Eventually, I hope to use this as a reference renderer when implementing a GPU and/or cloud renderer.

Working:

• loading obj files
• ray casting
• collision
• collision acceleration with simple spatial-split BVH
• path generation
• importance sampling
• multiple importance sampling (Balance)
• combining bidirectional paths (except for t==0 and t==1 which are planned but NYI)
• diffuse surfaces
• specular surfaces

Known bugs:

• Sample 0 does not display correctly
• Bidirectional cannot currently handle specular surfaces

Planned features:

• textures
• bump mapping
• normal smoothing
• transmissive materials
• glossy materials

Optimistic possible features:

• Metropolis light transport
• GPU suport
• Cloud rendering

There were some sample images here but they were terrible. Better renders coming soon.