A Vertex Program for Efficient Box-Plane Intersection

Object-order texture-based volume rendering decomposes the volume data set into stacks of textured polygons. The performance of such hardwarebased volume rendering techniques is clearly dominated by the fill-rate and the memory bandwidth, while only very little workload is assigned to the vertex processor. In this paper we discuss a vertex program which efficiently computes the slicing for texture-based volume rendering. This novel technique enables us to balance the workload between vertex processor, fragment processor and memory bus. As a result we demonstrate that the performance of texture-based volume rendering can be efficiently enhanced by trading an increased vertex load for a reduced fragment count. As an application we suggest a novel approach for empty space skipping for object-order volume rendering.