A shared-scene-graph image-warping architecture for VR: Low latency versus image quality

Designing low end-to-end latency system architectures for virtual reality is still an open and challenging problem. We describe the design, implementation and evaluation of a client–server depthimage warping architecture that updates and displays the scene graph at the refresh rate of the display. Our approach works for scenes consisting of dynamic and interactive objects. The end-to-end latency is minimized as well as smooth object motion generated. However, this comes at the expense of image quality inherent to warping techniques. To improve image quality, we present a novel way of detecting and resolving occlusion errors due to warping. Furthermore, we investigate the use of asynchronous data transfers to increase the architecture’s performance in a multi-GPU setting. Besides polygonal rendering, we also apply image-warping techniques to iso-surface rendering. Finally, we evaluate the architecture and its design trade-offs by comparing latency and image quality to a conventional rendering system. Our experience with the system confirms that the approach facilitates common interaction tasks such as navigation and object manipulation. & 2009 Elsevier Ltd. All rights reserved.