HashPoint: Accelerated Point Searching and Sampling for Neural Rendering
Authors: Jiahao Ma, Miaomiao Liu, David Ahmedt-Aristizabal, Chuong Nguyen

In this paper we address the problem of efficient point searching and sampling for volume neural rendering. Within this realm two typical approaches are employed: rasterization and ray tracing. The rasterization-based methods enable real-time rendering at the cost of increased memory and lower fidelity. In contrast the ray-tracing-based methods yield superior quality but demand longer rendering time. We solve this problem by our HashPoint method combining these two strategies leveraging rasterization for efficient point searching and sampling and ray marching for rendering. Our method optimizes point searching by rasterizing points within the camera's view organizing them in a hash table and facilitating rapid searches. Notably we accelerate the rendering process by adaptive sampling on the primary surface encountered by the ray. Our approach yields substantial speed-up for a range of state-of-the-art ray-tracing-based methods maintaining equivalent or superior accuracy across synthetic and real test datasets. The code will be available at https://jiahao-ma.github.io/hashpoint/