RTSG: Ray Tracing for X3D via a Flexible Rendering Framework

Abstract

VRML and X3D are the most widely adopted standards for interactive 3D content interchange. However, they are both designed around the common restricted functionality available in hardware graphics processors. Thus, most existing scene graph implementations are tightly integrated with rasterization APIs, which have difficulties simulating advanced global lighting effects. Conversely, complex photo-realistic effects are naturally supported by ray tracing based rendering algorithms [Glassner 1989]. Due to recent research advances and the constantly increasing computing power of commodity PCs, ray tracing is emerging as an interesting alternative for interactive applications. In this paper we present RTSG (Real-Time Scene Graph), a flexible scene management and rendering system. RTSG is X3D-compliant and has been designed to efficiently support both ray tracing and rasterization using a backend-independent rendering infrastructure. We describe two ray tracing and one rasterization backends and demonstrate that they achieve real-time rendering performance.