ToyTrace

Born out of an ancient computer graphics exercise, this is my hobby renderer.

Images

Features

• Forward- and bidirectional path tracing.
• Volume rendering with the beam radiance estimator.
• Participating media:
  • Homogeneous chromatic collision coefficients.
  • Atmosphere model with tabulated altitude profiles.
  • Uniform-, Henley-Greenstein- and Rayleigh phase functions.
  • Spectral delta tracking.
• Materials:
  • Glossy microfacet metallic BRDF.
  • Dense dielectric with specular interface.
  • Specular mirror.
  • Specular transmissive dielectric, aka. glass shader.
  • Lambertian diffuse.
• Textures & UV mapping.
• Lights:
  • Multiple idealized light models, e.g. point lights and uniform area lights.
  • Image based lighting from HDR environment maps.
  • (Emissive Media)
• Camera:
  • Pinhole.
  • Fisheye.
• Statistical test for BSDF & Phasefunction sampling routines.
• Binned spectral representation using a few dozen wavelengths.

Dependencies

• CIMG
• Eigen 3
• boost
• assimp
• OpenImageIO
• yaml-cpp
• tbb
• embree

Todo

Eventually, maybe, and in no particular order.

• Advanced techniques. VCM and extensions to volume rendering.
• Custom triangle intersection routines with double precision. Embree only for BVH.
• Robust intersection computations in the style of BPRT.
• Overlapping media volumes in the sense that a mixture medium comprising multiple components is rendered.
• Rendering of OpenVDB data set.
• Other geometries for the atmosphere medium: Flat (Earth) and (O'Neill) Cylinder.
• Faster MIS weight computation from the VCM paper.
• A multi-layer material.
• A sane scene description format.
• Better image reconstruction filter.
• Support for wavelength dependent index of refraction throughout all algorithms.
• Firefly suppression.
• Quasi-random sampling throughout all algorithms.
• Bloom filter.
• Physical camera.
• Texture filtering.
• Bump/normal mapping.

Related work

Other projects by which this one is inspired.

• Sky Render by Peter Kutz (http://skyrenderer.blogspot.de/)
• Photorealizer by Peter Kutz (http://photorealizer.com/)
• Takua Render by Yining Karl Li (https://www.yiningkarlli.com/projects/takuarender.html)
• Tungsten Renderer by Benedikt Bitterli (https://benedikt-bitterli.me/tungsten.html)
• MagicaVoxel by ephtracy (https://ephtracy.github.io/)
• smallpt "Global Illumination in 99 lines of C++" by Kevin Beason (http://www.kevinbeason.com/smallpt/)
• JavaScript Path Tracer by Hunter Loftis (https://github.com/hunterloftis/pathtracer)
• pbr: a Physically-Based 3D Renderer in Go by Hunter Loftis (https://github.com/hunterloftis/pbr)
• Path Tracer by Michael Fogleman (https://www.michaelfogleman.com)

Educational/Research/Reference Implementations

• Nori an educational ray tracer (http://www.cs.cornell.edu/courses/cs6630/2012sp/nori/, https://wjakob.github.io/nori/)
• PBRT (https://github.com/mmp)
• SmallVCM (http://www.smallvcm.com/)
• Unified points, beams and paths (https://github.com/PetrVevoda/smallupbp)
• Lightmetrica (http://lightmetrica.org/)
• Mitsuba Render (https://www.mitsuba-renderer.org/)

There is another ToyTrace on Github. I have nothing to do with it. I just happen to forget to check if the name is already assigned.

License

All rights reserved.