© Andreas Wendleder 2019-2026
Let Gemini praise the source:
Gonzales is a physically-based renderer built from the ground up in Swift 6.2, designed for high-end light transport simulation and research. By leveraging advanced sampling heuristics and a native acceleration architecture, it achieves production-grade results in complex scenes like the Disney Moana Island and Bitterli benchmarks — all without external C++ acceleration dependencies.
Implements robust MIS using the Power Heuristic to balance light source sampling (Next Event Estimation) and BRDF sampling. This significantly reduces variance and eliminates "fireflies" in challenging lighting conditions, such as small, intense emitters or highly glossy surfaces.
Featuring a native Bounding Volume Hierarchy (BVH) optimized specifically for Swift's performance characteristics. Gonzales provides efficient ray-primitive intersection using a custom implementation of the Surface Area Heuristic (SAH), removing the need for external libraries like Intel Embree.
- Z-Sobol Quasirandom Sampling: Utilizes high-dimensional Sobol sequences for superior convergence rates and improved blue-noise characteristics compared to standard pseudorandom methods.
- Xoshiro256**: Features a custom implementation of the Xoshiro256** generator for ultra-fast, high-quality local randomness.
- Russian Roulette: Optimized path termination heuristics to maintain computational efficiency in deep-bounce indirect lighting simulations.
- Power-Based Light Sampling: Efficiently handles scenes with high light counts by sampling based on cumulative power distributions.
- PBRT-v4 Support: Native parsing and rendering of the industry-standard PBRT-v4 scene format.
- Ptex & OpenImageIO: Deep integration with Ptex textures and OIIO for professional-grade image handling and texturing.
v0.0, 2021: 2048x858, 64spp, 26h on a Google Compute Engine with 8 CPUs and 64 GB of memory. Memory usage was around 50GB.
v0.1, 2023: Rendering Moana with a little help from Embree takes 78 minutes (1920x800, 64spp, AMD Threadripper 1920x 12 cores 24 threads, 64GB RAM, 80GB swap)
v0.2, 2026: Cleanup, tuning to get rid of ARC traffic, removal of Embree.
yay gonzales-git
https://aur.archlinux.org/packages/gonzales-git
- Get scenes from https://benedikt-bitterli.me/resources in pbrt v4 format and try them out.
- Get scenes from https://github.com/mmp/pbrt-v4-scenes and try them. All of them should be parsed correctly, not all of them work because an algorithm (subsurface scattering, volume rendering, ...) is missing.
PBRT was an inspiration since it was called lrt.
For Swift 6.1.2 and later the following has to be done on Arch Linux because of an incompatibility with GCC 15:
+ #if 0
#if __has_include(<math.h>)
#endif
+ #endif
in /usr/lib/swift/lib/swift/_FoundationCShims/_CStdlib.h +55.