3D Gaussian Splatting (3DGS) has demonstrated impressive capabilities in novel view synthesis. However, rendering reflective objects remains a significant challenge, particularly in inverse rendering and relighting. We introduce RTR-GS, a novel inverse rendering framework capable of robustly rendering objects with arbitrary reflectance properties, decomposing BRDF and lighting, and delivering credible relighting results. Given a collection of multi-view images, our method effectively recovers geometric structure through a hybrid rendering model that combines forward rendering for radiance transfer with deferred rendering for reflections. This approach successfully separates high-frequency and low-frequency appearances, mitigating floating artifacts caused by spherical harmonic overfitting when handling high-frequency details. We further refine BRDF and lighting decomposition using an additional physically-based deferred rendering branch. Experimental results show that our method enhances novel view synthesis, normal estimation, decomposition, and relighting while maintaining efficient training inference process.

翻译：三维高斯溅射（3DGS）在新视角合成中展现出卓越性能，但渲染反射物体仍是重大挑战，尤其在逆向渲染与重光照任务中。本文提出RTR-GS——一种新型逆向渲染框架，能够稳健渲染具有任意反射属性的物体，分解双向反射分布函数（BRDF）与光照，并提供可靠的重光照结果。给定多视角图像集合，本方法通过混合渲染模型有效恢复几何结构：结合前向渲染处理辐射传输，并采用延迟渲染处理反射。该策略成功分离高频与低频外观特征，缓解了处理高频细节时球谐函数过拟合导致的悬浮伪影。我们进一步通过基于物理的延迟渲染分支优化BRDF与光照分解。实验结果表明，本方法在保持高效训练推理过程的同时，显著提升了新视角合成、法向估计、材质分解及重光照的质量。