An Implementation of Multi-Chip Architecture for Real-Time Ray Tracing Based on Parallel Frame Rendering

In this paper, we propose a multi-chip architecture based on parallel frame rendering suitable for real-time ray tracing in dynamic scenes. In multi-chip architecture with the commonly used screen partitioning method, the acceleration structure data, such as a tree, updated in a dynamic scene must be transmitted to each chip. In the proposed frame division method, a tree build and ray tracing are performed on the same chip, and each frame is allocated to a predesignated multi-chip. Thus, the proposed method can achieve scalable performance improvement not only of ray tracing but also of a tree build. We implemented a multi-chip architecture on three field-programmable gate array (FPGA) boards and built 12 ray-tracing cores in the FPGA chip of each board. This configuration means that the inter-chip operates using the frame division method, while the inner chip operates using the screen partitioning method. The results of experiments showed that the proposed multi-chip architecture improved frames per second (FPS) performance by an average of 2.83 times compared to a single-chip architecture.