Efficient Ray Tracing of Gaussian Scenes and Semi-Transparent Surfaces

Develop efficient algorithms for ray tracing 3D Gaussian radiance fields and, more broadly, semi-transparent surfaces, achieving practical performance while preserving accurate image formation.

Background

The paper motivates a shift from rasterization to ray tracing for particle-based radiance fields to support complex cameras, secondary rays, and stochastic sampling. However, it explicitly notes that efficiently ray tracing Gaussian scenes and semi-transparent surfaces is not yet a solved problem, motivating the specialized algorithm introduced in the work.

Prior approaches for semi-transparent particles and volumes are cited as either ineffective on dense, non-uniform particle reconstructions or as relying on approximations that harm differentiability or quality, underscoring the need for more efficient and accurate methods.

References

Efficiently ray tracing Gaussian scenes (and more generally semi-transparent surfaces) is not a solved problem .

— 3D Gaussian Ray Tracing: Fast Tracing of Particle Scenes  (2407.07090 - Moenne-Loccoz et al., 2024) in Section 1 (Introduction)

Handling multiple mirrors or higher-order inter-reflection effects would require extending the geometric projection stage, which we leave for future work.

— Fill My Mirror: Geometry-Constrained Mirror Inpainting  (2609.03740 - Basson et al., 3 Sep 2026) in Section 5, Limitations

For indoor multipath-dominated environments where second- and third-order reflections carry comparable energy to direct returns, multi-bounce path tracing in the style of MC ray tracers (e.g., Sionna~RT) would remain necessary; integrating the closed-form BSDF + PSF splatting recipe into a multi-bounce framework is open.

— 3D Point Splatting for mmWave Radar Novel View Synthesis  (2609.11894 - Armouti et al., 10 Sep 2026) in Section “Limitations and future work,” Appendix, Section \ref{app:limitations}