etx-tracer

Physically-based ray-tracer.

Features

• Vertex Connection and Merging algorithm
• Full-spectral rendering (by sampling single wavelength per ray)
• Mdium rendering
• Volumetric Bidirectional Path Tracing integrator
• Variety of BSDFs:
  • basic materials - diffuse, plastic, conductor, dielectric
  • additionaal materials - thinfilm, coating, mirror, velvet
• Variety of emitters
  • area;
  • environment map;
  • directional emitter with finite angluar size
  • collimated area lights (lasers)
• Spectral representation of material's properties (colors, index of refractions, etc)
• Subsurface scattering:
  • random walk;
  • Christensen-Burley approximation;
  • could be applied to any material containing diffuse layer (diffuse, plastic, velvet)
• Thin-film rendering over all materials (including conductors)
• Normal mapping
• Atmosphere integrator;

Samples

Several renderings from the ray-tracer. Samples contains showcase for materials, volumetric data rendering, spectral rendering, participating media rendering, subsurface scattering and SDS (specular-diffuse-specular paths), which are usually tricky thing to render. As well as thin film rendering, collimated emitters, depth of field, and other effects.

More renderings could be found in my Twitter:

Story behind this project

This project is a fusion of several my previous projects

• et-engine - the old game engine, which actually was used in several shipped games;
• etx - an extension to the engine, which is used for UI;
• metal-ray-tracer - ray-tracer based on Metal Performance Shaders.

Project milestones:

Order is a subject to change, but here are main things to do:

• boilerplate code for window, input handling, etc;
• basic boilerplate code for ray-tracing;
• simplest CPU path-tracer;
• OptiX and GPU-related code basics;
• additional code for ray-tracing;
• GPU path tracing;
• VCM integrators (CPU and GPU);
• Subsurface scattering;
• cross-platform, cross-API support; ... maintaining code, adding new features.

Building

This part of the description would be updated during the development of the project, at the moment there is nothing to build here. All updates will be located here: BUILDING.md

Sponsors

This project is GitHub-sponsored by:

• Traverse-Research

Links

Links to the books/papers/publications/resources I've used during the development:

• PBRT book
• VCM paper / implementation
• Rendering resources by Benedikt Bitterli
• Multiple-Scattering Microfacet BSDFs with the Smith Model