Video for IEEE TVCG: encoded with MPEG-4 (51MB)
(You can download DivX codec from DivX.com and QuickTime from QuickTime)
These images show the application of Quick-VDR to a complex isosurface (100M trianlges) generated from a very high resolution 3D simulation of Richtmyer-Meshkov instability and turbulence mixing. The middle and right images show zoomed views. The isosurface has high depth complexity, holes, and a very high genus. Quick-VDR can render it at 11 - 21 frames per second on a PC with NVIDIA GeForce FX5950 card and uses a memory footprint of 600MB.
We present a novel approach for interactive view-dependent rendering of massive models. Our algorithm combines view-dependent simplification, occlusion culling, and out-of-core rendering. We represent the model as a clustered hierarchy of progressive meshes (CHPM). We use the cluster hierarchy for coarse-grained selective refinement and progressive meshes for fine-grained local refinement. We present an out-of-core algorithm for computation of a CHPM that includes cluster decomposition, hierarchy generation, and simplification. We make use of novel cluster dependencies in the preprocess to generate crack-free, drastic simplifications at runtime. The clusters are used for occlusion culling and out-of-core rendering. We add a frame of latency to the rendering pipeline to fetch newly visible clusters from the disk and avoid stalls. The CHPM reduces the refinement cost for view-dependent rendering by more than an order of magnitude as compared to a vertex hierarchy. We have implemented our algorithm on a desktop PC. We can render massive CAD, isosurface, and scanned models, consisting of tens or a few hundred million triangles at 10-35 frames per second with little loss in image quality.
CHPM: Clustered Hierarchy of Progressive Meshes. At runtime the active cluster list (ACL) represents a front in the cluster hierarchy containing the clusters of the current mesh (left). Clusters on the ACL are classified as visible, frustum culled, or occlusion culled. The PMs (right) of visible clusters are refined to meet the screen space error bound by selecting a mesh from the PM mesh sequence. When the ACL changes, smooth LOD transitions occur because the most refined mesh of each PM is equal to the union of the base meshes of its children.
Quick-VDR: Out-of-Core View-Dependent Rendering of Gigantic Models , IEEE Transactions on Visualization and Computer Graphics, July/August 2005, p369-382
IEEE Visualization 04 talk slides: Power point slides
Quick-VDR: Interactive View-Dependent Rendering of Massive Models , Technical Report, TR04-11 , University of North Carolina at Chapel Hill.
Fast Collision Detection betwen Massive Models using Dynamic Simplification
Interactive View-dependent Rendering with Conservative Occlusion Culling in Complex Environments
UNC Walkthru Group
CB #3175, Department of Computer Science
University of North Carolina
Chapel Hill, NC 27599-3175