Combined 3D visualization of volume data and polygonal models using a Shear-Warp algorithm

Shear-Warp techniques provide an e$cient way to perform the projection and blending stages of the volume-rendering process. They treat volume-data slices in a coherent order and can be naturally integrated with the Z-Bu!er algorithm. The present paper presents a study on the integration between Shear-Warp and Z-Bu!er, and extends the Shear-Warp algorithm to handle scenes composed of both volume and polygonal data. We present methods to handle opaque/translucent volumes combined with opaque/translucent polygonal models. As volume data usually has a di!erent resolution from that of the "nal image, in which Z-Bu!er renders the polygonal data, several variants for this integration are analyzed. Results are shown to support some conclusions on the trade-o! quality versus time that can be expected. ( 2000 Elsevier Science Ltd. All rights reserved.