Hardware-Accelerated Particle-Based Volume Rendering for Multiple Irregular Volumes

In this paper, we propose a performance improvement of particle-based volume rendering (PBVR) by using a current, programmable GPU architecture. PBVR allows to render without visibility sorting by representing a given volume dataset as a set of opaque and emissive particles. In our new GPU acceleration of PBVR, we provide a switchable rendering pipeline that is compatible with both regular and irregular and volumes. Particle generation is improved by using a cell-by-cell approach for processing large volume dataset. We also reduce the memory cost required for storing all sub-pixel values by proposing a pixel-superimposing technique targeting a large sub-pixel level. Our work demonstrates a full detail rendering rate from 5 to 11 fps for overlapped or separated multi-irregular volumes with a mega-scale number of volume cells on NVIDIA Geforce 8800GTX.