T-ReX: Interactive Global Illumination of Massive Models on Heterogeneous Computing Resources

Abstract

We propose several interactive global illumination techniques for a diverse set of massive models. We integrate these techniques within a progressive rendering framework that aims to achieve both a high rendering throughput and an interactive responsiveness. To achieve a high rendering throughput, we utilize heterogeneous computing resources consisting of CPU and GPU. To reduce expensive data transmission costs between CPU and GPU, we propose to use separate, decoupled data representations dedicated for each CPU and GPU. Our representations consist of geometric and volumetric parts, provide different levels of resolutions, and support progressive global illumination for massive models. We also propose a novel, augmented volumetric representation that provides additional geometric resolutions within our volumetric representation. In addition, we employ tile-based rendering and propose a tile ordering technique considering visual perception. We have tested our approach with a diverse set of large-scale models including CAD, scanned, simulation models that consist of more than 300 million triangles. By using our methods, we are able to achieve ray processing performances of 3 M similar to 20 M rays per second, while limiting response time to users within 15 similar to 67 ms. We also allow dynamic modifications of light, and interactive setting of materials, while efficiently supporting novel view rendering.