We present MaterialClusterGS, a palette-based material decomposition framework for 2D Gaussian Splatting that enables physically based relighting and material editing. Existing Gaussian inverse rendering methods typically assign independent BRDF parameters to individual primitives. While flexible, this local fitting strategy makes material recovery highly under-constrained: shadows, indirect illumination, geometric errors, and visibility residuals can be absorbed into thousands of slightly different local material estimates. Meanwhile, recent palette-based appearance methods operate solely in RGB space without modeling physical materials or illumination. To bridge this gap, we represent scene materials using a compact global palette of shared BRDF prototypes assigned via a continuous spatial material field. Without shared material structure, editing one region does not propagate consistently to others of the same material, making per-primitive decompositions impractical for editing. We jointly optimize the material field, palette prototypes, and environment lighting under a physically based rendering objective. The resulting framework recovers compact, spatially coherent attributes directly usable for material editing, relighting, and transfer.

翻译：我们提出MaterialClusterGS——一种面向二维高斯溅射的基于调色板的材质分解框架，支持物理基重照明与材质编辑。现有高斯逆渲染方法通常为每个独立图元分配独立的BRDF参数。这种局部拟合策略虽具灵活性，却使材质恢复高度欠约束：阴影、间接光照、几何误差及可见性残差可被吸收至数千个轻微差异的局部材质估计中。与此同时，近期基于调色板的外观方法仅在RGB空间中操作，未建模物理材质或光照。为弥合这一鸿沟，我们采用通过连续空间材质场分配的共享BRDF原型紧凑全局调色板表示场景材质。缺乏共享材质结构时，编辑某一区域无法一致传播至同材质的其他区域，这使得基于图元的分解方案对编辑操作不具实用性。我们在物理基渲染目标下联合优化材质场、调色板原型及环境光照。所得框架可直接恢复紧凑且空间一致的属性，用于材质编辑、重照明与材质迁移。