GPU Based Real-time Shadow Research

Shadow can strengthen the reality of 3D virtual scene and provide important visual information for the objects´ spatial relationship in the scene. This paper presents a GPU based method for all the process of shadow volume algorithm. It can achieve greater shadow performance in ship-handling simulator than previous methods by migrating the silhouette extraction and shadow volume rending to GPU, and applying a series of techniques for culling, clipping, and simplifying shadow volume geometry. We make a series of optimization for the visual system of the ship-handling simulator such as limit the range of illumination, the alternation of z-pass and z-fail algorithm, using the ultra shadow technology and two sided stencil buffer to accelerate the rending of shadow