Vorion: A RISC-V GPU with Hardware-Accelerated 3D Gaussian Rendering and Training
Yipeng Wang, Mengtian Yang, Chieh-pu Lo, Jaydeep P. Kulkarni
TL;DR
Vorion targets real-time 3D Gaussian Splatting (3DGS) by introducing hardware-accelerated rendering and training via a unified Gaussian rasterizer. The key ideas are large-tile processing, z-tiling for depth-parallelism, and a hybrid Gaussian/pixel dataflow to mitigate alpha blending and gradient accumulation bottlenecks. Hardware experiments on a 16 nm prototype show 19 FPS rendering and 38.6 iterations/s training in a scaled configuration, with up to 152 FPS rendering and 38.6 iterations/s training as resources scale, indicating strong near-linear scalability. These results suggest real-time 3DGS is feasible on next-generation GPUs, enabling edge AR/VR, robotics, and dynamic scene capture.
Abstract
3D Gaussian Splatting (3DGS) has recently emerged as a foundational technique for real-time neural rendering, 3D scene generation, volumetric video (4D) capture. However, its rendering and training impose massive computation, making real-time rendering on edge devices and real-time 4D reconstruction on workstations currently infeasible. Given its fixed-function nature and similarity with traditional rasterization, 3DGS presents a strong case for dedicated hardware in the graphics pipeline of next-generation GPUs. This work, Vorion, presents the first GPGPU prototype with hardware-accelerated 3DGS rendering and training. Vorion features scalable architecture, minimal hardware change to traditional rasterizers, z-tiling to increase parallelism, and Gaussian/pixel-centric hybrid dataflow. We prototype the minimal system (8 SIMT cores, 2 Gaussian rasterizer) using TSMC 16nm FinFET technology, which achieves 19 FPS for rendering. The scaled design with 16 rasterizers achieves 38.6 iterations/s for training.
