https://github.com/nelarius/rayfinder
An interactive, experimental, pathtracer implemented using desktop WebGPU.
https://github.com/nelarius/rayfinder
computer-graphics cpp raytracer webgpu
Last synced: 12 months ago
JSON representation
An interactive, experimental, pathtracer implemented using desktop WebGPU.
- Host: GitHub
- URL: https://github.com/nelarius/rayfinder
- Owner: Nelarius
- License: mit
- Created: 2023-10-29T08:57:53.000Z (over 2 years ago)
- Default Branch: main
- Last Pushed: 2024-07-14T04:36:44.000Z (over 1 year ago)
- Last Synced: 2025-04-04T15:06:32.226Z (12 months ago)
- Topics: computer-graphics, cpp, raytracer, webgpu
- Language: C
- Homepage: https://nelari.us/post/pathtracer_devlog/
- Size: 51.1 MB
- Stars: 32
- Watchers: 2
- Forks: 1
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# rayfinder
An interactive experimental pathtracer, implemented using WebGPU via the [Dawn](https://dawn.googlesource.com/dawn) renderer.
## Showcase
## References
- [WGSL offset computer](https://webgpufundamentals.org/webgpu/lessons/resources/wgsl-offset-computer.html)
- Great tool for checking correct memory layout
- _Physically Based Rendering, fourth edition_
- Bounding volume hierarchy
- Inverse transform sampling method
- [Ray Tracing: The Rest of Your Life](https://raytracing.github.io/books/RayTracingTheRestOfYourLife.html)
- Cosine-weighted hemisphere sampling method
- [scratchapixel/moller-trumbore-ray-triangle-intersection](https://www.scratchapixel.com/lessons/3d-basic-rendering/ray-tracing-rendering-a-triangle/moller-trumbore-ray-triangle-intersection.html)
- _The Reference Path Tracer_, _Ray Tracing Gems II_ and associated code sample [boksajak/referencePT](https://github.com/boksajak/referencePT/)
- Rng initialization
- Next event estimation (direct light sampling) method
- [Crash Course in BRDF implementation](https://boksajak.github.io/files/CrashCourseBRDF.pdf)
- BRDF interface
- Lambertian BRDF, `sampleLambertian`, `evalLambertian`
- [Building an Orthonormal Basis, Revisited](https://www.jcgt.org/published/0006/01/01/paper-lowres.pdf)
- Robust orthonormal axis, implemented in the `pixarOnb` function
- _A Fast and Robust Method for Avoiding Self-Intersection_, _Ray Tracing Gems_
- Method for the `offsetRay` function, for preventing ray self-intersections.
- _Sampling Transformations Zoo_, _Ray Tracing Gems_
- The `rngNextInCone` method and source
- [ACES Filmic Tone Mapping Curve](https://knarkowicz.wordpress.com/2016/01/06/aces-filmic-tone-mapping-curve/)
- filmic tonemapping function
- [Simple Analytic Approximations to the CIE XYZ Color Matching Functions](https://jcgt.org/published/0002/02/01/)
- C code for the CIE XYZ color matching functions' multi-lobe Gaussian fit
- [RGB / XYZ conversion matrices](http://www.brucelindbloom.com/index.html?Eqn_RGB_XYZ_Matrix.html)
- XYZ to sRGB conversion matrix
- [Sky Dome Appearance Project](https://cgg.mff.cuni.cz/projects/SkylightModelling/)
- The original source of the sky and solar disk model
- The following [Rust implementation](https://github.com/phoekz/hw-skymodel) serves as the basis of the much simplified C code used in this project.
- Depth precision and reverse Z projection
- [Depth Precision Visualized](https://www.reedbeta.com/blog/depth-precision-visualized/)
- [Reverse Z (and why it's so awesome)](https://tomhultonharrop.com/mathematics/graphics/2023/08/06/reverse-z.html)
- [Free blue noise textures](http://momentsingraphics.de/BlueNoise.html)
- _Using Blue Noise for Ray Traced Soft Shadows_, _Ray Tracing Gems II_
## Build
A C++20 compiler is required.
```sh
$ cmake -B build -DCMAKE_BUILD_TYPE=Debug
$ cmake --build build --target pt -- -j 32
```
On Windows, the platform name (`x64`, `Win32`, `ARM64`) should be provided during configuration. CMake defaults to `Win32` -- see [cmake-preset-x64-arch.md](notes/cmake-presets-x64-arch.md) for instructions on setting up a CMake Preset to force `-A x64`.
```sh
$ cmake -B build -A x64 -DCMAKE_BUILD_TYPE=Debug
```
The shaders are appended to a header file as raw strings during the `pt` build step. Updating the header file can also be invoked manually:
```sh
$ cmake --build build --target bake-wgsl
```
It's recommendable to build using ccache in case Dawn ever needs to be rebuilt. See [ccache.md](notes/ccache.md) for instructions.
## Run
### `pt` and `pt-format-tool`
The `pt` executable contains the path tracer. You run it by providing it with input file in the `pt` file format. `.pt` files are generated from a glTF file using the `pt-format-tool` executable.
```sh
# Running the path tracer requires input data generated from a gltf file.
$ ./build-release/pt-format-tool assets/Sponza.glb
# Run the path tracer with the resulting .pt file.
$ ./build-release/pt assets/Sponza.pt
```
### `bvh-visualizer`
For validating that the bounding volume hierarchy (BVH) and it's intersection tests are computed correctly. This executable loads the specified glTF file, builds a BVH, and produces an image where each pixel is colored by the number of nodes visited for the pixel's primary ray. Running the executable produces the test image `bvh-visualizer.png`.
```sh
$ ./build-release/bvh-visualizer assets/Duck.glb
```
### `hw-skymodel-demo`
Running the `hw-skymodel-demo` target generates a test image `hw-skymodel-demo.png`.
### `tests`
To run the tests, the working directory has to be in the build folder. The tests depend on assets which are copied to the build folder.
```sh
$ (cd build-debug && ./tests)
```
### `textractor`
For validating that textures are loaded correctly. Loads the specified glTF model and its base color textures, and dumps the textures into `.png` files.
```sh
$ ./build-release/textractor assets/Sponza.glb
```