The research on 3D model retrieval is a new hot point and meanwhile a difficult problem in the area of content based retrieval. In this paper, a novel 3D model retrieval and visualization engine, 3DMIRACLES (3D Multimedia Information RetrievAl, CLassification and Exploration System), has been developed, which integrates effective algorithms and techniques for both shape-based retrieval computation of 3D models and real-time visualization of the retrieval results in
realistic 3D interactive mode. The system architecture of 3DMIRACLES has been proposed. For retrieval computation, new algorithms have been developed and implemented for 3D shape feature extraction and similarity matching, which mainly include slice based method, Delta functions method, thickness histogram method and directional form, etc. For interactive visualization, a novel 3D viewer has been developed based on the foundational programming library of 3D drawing developed by our group, which implements hybrid rendering method to make much simplification and shortcut processing of 3D rendering computation for achieving high speed and efficient real-time visualization of large scale 3D databases. Evaluation experiments show that 3DMIRACLES is successful and effective in 3D shape retrieval and visualization for large scale 3D model databases, and the research achievements may be applied to real application system.