cpbrt: A C++ repository from carlos-lopez-garces

CPBRT is my physically-based, offline toy renderer. It is the result of studying Physically Based Rendering: From Theory to Implementation, by Pharr, Jakob, and Humphreys (online edition), writing down the code fragments provided by the authors, and filling in the gaps.

A more detailed description is found in my blog.

Features

Light transport algorithms: Kajiya path tracing (unidirectional, unbiased Monte Carlo estimation of the light transport equation). Direct-lighting (no indirect illumination) and path (full global illumination) integrators.	Reflectance models and BRDFs: Lambert diffuse model, Oren-Nayar diffuse model for rough surfaces, Fresnel perfectly specular model, and Fresnel glossy specular model (with Torrance-Sparrow microfacets with Beckmann-Spizzichino or Trowbridge-Reitz distributions).
Textures: Floating-point and spectrum constant-value textures. Procedural checkerboard texture, antialiased with a box filter. Mipmapping.	Materials: Matte with either a perfect diffuse Lambertian BRDF or an Oren-Nayar BRDF for various degrees of roughness; plastic with diffuse and glossy specular BRDFs; mirror with a perfectly-specular BRDF; gold; glass with perfectly-specular BRDF and BTDF; diffuse substrate and glossy coat with an Ashikhmin-Shirley BRDF.
Shapes: Triangle meshes, single triangles, and spherical implicit surfaces.	Accelerators: BVH with 5 different primitive (or object) subdivision methods: linear BVH, hierarchical linear BVH, midpoint partitioning, equal counts partitioning, and surface area heuristic (SAH).
Samplers: Uniform or jittered stratified pixel sampling for 1D samples and Latin Hypercube sampling for 2D samples. Samplers rely on a Permuted Congruential Generator (PCG) pseudo-random number generator.	Filters: Box, triangle, Gaussian, Mitchell-Netravali, and Lanczos windowed-sinc filters.
Lights: Point, distant, and diffuse area light sources. An area light can take the form of any of the supported shapes. Infinite area light source backed by environment map.	Cameras: Thin lens perspective and orthographic projective cameras with configurable aperture and focal distance (for depth of field) and film aspect ratio. The perspective camera also has a configurable field of view.
Participating media: Homogeneous-density and grid-based variable-density media.

Select images

Diffuse substrate and glossy coat with an Ashikhmin-Shirley BRDF. Volumetric path integrator.	Diffuse substrate and glossy coat with an Ashikhmin-Shirley BRDF.
10mm fish-eye lens.	Subsurface scattering, skin material.
Glass material, lit with an infinite area light backed by a latitude-longitude radiance map.	Glass material, volumetric path tracing; a bug prevents the environment map from being sampled.
Metal material, lit with an infinite area light backed by a latitude-longitude radiance map.	Gold material, Torrance-Sparrow microfacets with Trowbridge-Reitz distribution.
Ganesha mesh by Wenzel Jakob; notice the absence of shadows (wrong).	Participating media. Not working yet.
Cornell box, direct lighting integrator, stratified sampling, 30 samples per pixel.	Cornell box, path integrator, stratified sampling, 10 samples per pixel.
Plastic material with Torrance-Sparrow microfacet BRDF to simulate glossy hard plastic.	Spherical diffuse area light, matte material with Lambertian reflection.
Spherical diffuse area light, plastic material w/o specular reflection.	Matte material with Oren-Nayar diffuse reflection.
Matte material with perfect Lambertian diffuse reflection.	Cover of the PBRT book by Yining Karl Li, perspective camera, 2 point lights, mirror material, specular BRDF.
Dragon triangle mesh by Christian Schüller, perspective camera, 2 point lights, matte material.	Cover of the PBRT book by Yining Karl Li, perspective camera, 2 point lights, matte material.
One triangle of a triangle mesh, matte material.	First render, implicitly defined sphere.