Recent advancements in Radiance Fields have significantly improved novel-view synthesis. However, in many real-world applications, the more advanced challenge lies in inverse rendering, which seeks to derive the physical properties of a scene, including light, geometry, textures, and materials. Meshes, as a traditional representation adopted by many simulation pipeline, however, still show limited influence in radiance field for inverse rendering. This paper introduces a novel framework called Triangle Patchlet (abbr. Triplet), a mesh-based representation, to comprehensively approximate these scene parameters. We begin by assembling Triplets with either randomly generated points or sparse points obtained from camera calibration where all faces are treated as an independent element. Next, we simulate the physical interaction of light and optimize the scene parameters using traditional graphics rendering techniques like rasterization and ray tracing, accompanying with density control and propagation. An iterative mesh extracting process is also suggested, where we continue to optimize on geometry and materials with graph-based operation. We also introduce several regulation terms to enable better generalization of materials property. Our framework could precisely estimate the light, materials and geometry with mesh without prior of light, materials and geometry in a unified framework. Experiments demonstrate that our approach can achieve state-of-the-art visual quality while reconstructing high-quality geometry and accurate material properties.

翻译：近年来，辐射场技术的进展显著提升了新视角合成的质量。然而，在许多实际应用中，更具挑战性的问题在于逆向渲染，即从场景中推导出包括光照、几何、纹理和材质在内的物理属性。网格作为许多仿真管线采用的传统表示方法，在辐射场逆向渲染中的应用仍显不足。本文提出了一种称为三角形面片（简称Triplet）的新型框架，这是一种基于网格的表示方法，用于全面近似这些场景参数。我们首先通过随机生成点或从相机标定获得的稀疏点来组装Triplet，其中所有面片均被视为独立元素。接着，我们模拟光的物理相互作用，并借助栅格化与光线追踪等传统图形渲染技术，结合密度控制与传播机制，对场景参数进行优化。我们还提出了一种迭代网格提取流程，通过基于图的操作持续优化几何与材质属性。此外，我们引入了若干正则化项以提升材质属性的泛化能力。该框架能够在无需光照、材质与几何先验知识的统一框架下，基于网格精确估计光照、材质与几何参数。实验表明，我们的方法在重建高质量几何与精确材质属性的同时，能够达到最先进的视觉质量。