Towards Accelerating Real-Time Path Tracing with Foveated Framework

Abstract: Path tracing is one of the most widespread rendering techniques for high-end graphics fidelity. However, the slow convergence time and presence of intensive noises make it infeasible for numerous real-time applications where physically corrected photorealistic effects are salient. Additionally, the increased demand for pixel density, geometric complexity, advanced material, and multiple lights hinder the algorithm from attaining an interactive frame rate for real-time applications. To address these issues, we developed a framework to accelerate path tracing through foveated rendering, a robust technique that leverages human vision. Our dynamic foveated path-tracing framework integrates fixation data and selectively lowers the rendering resolution towards the periphery. The framework is built on NVIDIA's OptiX 7.5 API with CUDA 12.1, serving as the base of future foveated path tracing research. Through comprehensive experimentation, we demonstrated the effectiveness of our framework in this paper. Depending on the scene complexity, our solution can significantly enhance rendering performance up to a factor of 25 without any notable visual differences. We further evaluated the framework using a structured error map algorithm with variable sample numbers and foveated area size.