Exploring global illumination for virtual reality

Real time global illumination (GI) is a difficult and steadily researched area. Advances in the field could potentially benefit virtual reality applications by increasing users' sense of presence. In immersive virtual environments (IVE) like CAVEs, applications must support perspective-corrected stereoscopic rendering. Dmitriev et al. [2004] performed GI in a CAVE using Precomputed Radiance Transfer, which requires a static scene. Mortensen et al. [2007] also performed GI in a CAVE using Virtual Light Fields which did not allow moving lights or geometry. We present our attempt to find GI techniques that support dynamic lights and scene geometry in our 6-sided CAVE-like IVE (DRIVE6). We implemented two separate illumination techniques: GPU photon mapping (GPM) and multiresolution splatting for indirect illumination (MSII). Each technique makes trade-offs between image quality and speed, and appropriate use of each depends on the needs of the application. Anecdotal evidence suggests that these techniques increase the sense of presence, warranting formal study. A user study is planned.