RetinaGS: Scalable Training for Dense Scene Rendering with Billion-Scale 3D Gaussians
Bingling Li, Shengyi Chen, Luchao Wang, Kaimin Liao, Sijie Yan, Yuanjun Xiong
TL;DR
RetinaGS tackles the scalability bottleneck of dense 3D Gaussian Splatting by introducing a model-parallel training framework that preserves the single-GPU rendering equation across distributed workers. It partitions the scene into overlapping convex subspaces via a KD-tree, computes subset-level colors and opacities in parallel, and merges them in the correct order to reproduce the full rendering result, enabling training with billions of primitives on multi-GPU clusters. The approach demonstrates consistent gains in rendering quality (PSNR/SSIM/LPIPS) as primitive counts increase and as training resolution and data scale rise, with a pioneering billion-primitive model trained on MatrixCity-ALL. The work also analyzes partitioning strategies and demonstrates substantial memory and throughput benefits of model parallelism over data parallelism, while acknowledging remaining challenges in load balancing and initialization throughput for future improvements.
Abstract
In this work, we explore the possibility of training high-parameter 3D Gaussian splatting (3DGS) models on large-scale, high-resolution datasets. We design a general model parallel training method for 3DGS, named RetinaGS, which uses a proper rendering equation and can be applied to any scene and arbitrary distribution of Gaussian primitives. It enables us to explore the scaling behavior of 3DGS in terms of primitive numbers and training resolutions that were difficult to explore before and surpass previous state-of-the-art reconstruction quality. We observe a clear positive trend of increasing visual quality when increasing primitive numbers with our method. We also demonstrate the first attempt at training a 3DGS model with more than one billion primitives on the full MatrixCity dataset that attains a promising visual quality.
