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.

翻译：三维高斯溅射技术在重建照片级真实感三维场景方面展现出巨大潜力。然而，这些方法通常将光照信息烘焙到其表示中，限制了其在基于物理的渲染和场景编辑中的应用。尽管近期的逆向渲染方法致力于将场景分解为材质和光照分量，但它们往往依赖于简化假设，在编辑时难以成立。本文提出一种新颖方法，通过屏幕空间光线追踪为三维高斯溅射实现高效的全局光照。我们的核心见解是：大量间接光照可以追溯至当前视锥体内可见的表面。基于这一观察，我们在三维高斯计算直接光照的基础上，引入蒙特卡洛屏幕空间光线追踪来捕捉单次反射间接光照。通过这种方式，本方法在保持三维高斯计算效率和可编辑性优势的同时，实现了逼真的全局光照效果。实验表明，我们所采用的屏幕空间近似方法能够有效计算间接光照，并支持实时渲染与编辑。代码、数据及模型将在项目页面发布：https://wuzirui.github.io/gs-ssr。