An Incremental Algorithm for Fast Rotation of Volumetric Data

Csébfalvi Balázs
Department of Process Control, Technical University of Budapest,
Budapest, Muegyetem rkp. 11, H-1111, HUNGARY


In this paper a new volume rendering method is presented which provides real-time rotation on SISD architectures without using any acceleration hardware. The algorithm is based on the efficient handling of empty voxels, where according to the opacity values a 3D binary mask is generated indicating the locations of the non-transparent voxels. Ray casting is performed on this binary mask which is rotated rapidly by shear-warp factorization and an incremental alignment technique. The location of a non-zero bit hit by a ray is mapped onto the corresponding voxel location in the original classified volume, in order to get the opacity and color values in the given sample point. The technique proposed for rotating and sampling the binary mask exploits only the standard ALU operations providing interactive frame rates even on low cost machines.


Volume Rendering, Ray Casting, Shear-Warp Factorization.