Moonshine

A spectral path tracer built with Zig + Vulkan

Salle de bain by nacimus, rendered with Moonshine

Features

• Binaries
  • offline -- a headless offline renderer
  • online -- a real-time windowed renderer
  • hydra -- a hydra render delegate
• Light Transport
  • Full spectral path tracing
  • Direct light sampling with multiple importance sampling for all lights and materials
• Lights
  • 360° environment maps
  • Emissive meshes
• Materials
  • Standard PBR with metallic + roughness
  • Mirror
  • Glass with dispersion

Dependencies

Build

• zig (see version in CI)
• DirectXShaderCompiler
• For the online (real-time) renderer:
  • For Linux (Ubuntu, similar on others):
    • For Wayland: wayland-protocols libwayland-dev libxkbcommon-dev
    • For X11: libxcursor-dev libxrandr-dev libxinerama-dev libxi-dev

Run

• A GPU supporting Vulkan ray tracing

// TODO

• Cameras
  • Fisheye
  • Lens System
• Materials
  • Conductor with complex IOR
  • Transmissive with roughness
  • Material composition
• Volumetrics
• Lights
  • Experiment with sampling triangle via solid angle after selecting it via area
  • Experiment with unifying sampling mesh lights and environment map
  • BVH
• Testing
  • Proper statistical tests GPU sampling routines
  • Proper statistical tests to make sure images have expected mean/variance
  • Should ensure validation layers are clean during tests
• Resource management
  • Make sure we have all necessary errdefers
  • GPU resource arrays should be resizable
  • Need some sort of way to do async/parallel resource creation (transfers, processing)
• Use physical (with correct scales) units
• Integrators
  • ReSTIR
• Spectral EXR output
• Tonemapping
• HDR display
  • A satisfying implementation is blocked by HDR display metadata querying in Vulkan

Some notes about conventions

• +z is up
• phi is azimuthal angle (0-2pi) and theta is polar angle (0-pi)

Some light reading

• Importance sampling
• Explicit light sampling
• Multiple importance sampling
• Microfacets
• Actual materials - ton of BRDF examples, in CODE!

License

This project is licensed under the AGPL.