In this paper, we introduce Ref-GS, a novel approach for directional light factorization in 2D Gaussian splatting, which enables photorealistic view-dependent appearance rendering and precise geometry recovery. Ref-GS builds upon the deferred rendering of Gaussian splatting and applies directional encoding to the deferred-rendered surface, effectively reducing the ambiguity between orientation and viewing angle. Next, we introduce a spherical Mip-grid to capture varying levels of surface roughness, enabling roughness-aware Gaussian shading. Additionally, we propose a simple yet efficient geometry-lighting factorization that connects geometry and lighting via the vector outer product, significantly reducing renderer overhead when integrating volumetric attributes. Our method achieves superior photorealistic rendering for a range of open-world scenes while also accurately recovering geometry.

翻译：本文提出Ref-GS，一种用于二维高斯泼溅中方向性光照分解的新方法，该方法能够实现照片级真实感的视点相关外观渲染与精确几何重建。Ref-GS基于高斯泼溅的延迟渲染框架，对延迟渲染后的表面施加方向性编码，有效降低了表面朝向与观察角度之间的歧义性。随后，我们引入球面Mip网格来捕捉不同层级的表面粗糙度，实现了粗糙度感知的高斯着色。此外，我们提出一种简洁高效的几何-光照分解方法，通过向量外积连接几何与光照信息，在集成体积属性时显著降低了渲染器的计算开销。本方法在一系列开放场景中实现了卓越的照片级真实感渲染效果，并同时精确恢复了场景几何结构。