Sample buffer: A progressive refinement ray-casting algorithm for volume rendering

Ray-casting has been shown to be an excellent technique for rendering volume data. This paper describes a new ray-casting algorithm that employs the concept of progressive refinement for volume rendering. Volume data are embedded into a complete octree, and when the volume data are rendered, the octree is traversed according to a user-defined threshold. By reducing this threshold gradually, we can render increasingly refined images. Ray-casting is used to explore the octree, and a data structure called a sample buffer (SB) is introduced to reduce the time required to render a series of images. With this method, a satisfactory balance between image quality and computation time can be achieved.