3D Gaussian Inverse Rendering with Approximated Global Illumination
Journal:
arXiv
Published Date:
Apr 2, 2025
Abstract
3D Gaussian Splatting shows great potential in reconstructing photo-realistic
3D scenes. However, these methods typically bake illumination into their
representations, limiting their use for physically-based rendering and scene
editing. Although recent inverse rendering approaches aim to decompose scenes
into material and lighting components, they often rely on simplifying
assumptions that fail when editing. We present a novel approach that enables
efficient global illumination for 3D Gaussians Splatting through screen-space
ray tracing. Our key insight is that a substantial amount of indirect light can
be traced back to surfaces visible within the current view frustum. Leveraging
this observation, we augment the direct shading computed by 3D Gaussians with
Monte-Carlo screen-space ray-tracing to capture one-bounce indirect
illumination. In this way, our method enables realistic global illumination
without sacrificing the computational efficiency and editability benefits of 3D
Gaussians. Through experiments, we show that the screen-space approximation we
utilize allows for indirect illumination and supports real-time rendering and
editing. Code, data, and models will be made available at our project page:
https://wuzirui.github.io/gs-ssr.
