Volumetric Model Repair for Virtual Reality Applications

Repairing Virtual Reality (VR) models is a challenge for productive applications. This paper describes a fast implementation of Nooruddin and Turk’s ray-stabbing method 14 based on standard graphics hardware. Raystabbing is used to convert a polygonal model into a volume model (also called voxelization). The volume model is back-converted into a polygonal model using the marching cubes (MC) algorithm 12 and the QSlim algorithm 7 for reducing the extracted polygon model. The overall process yields a properly closed polygonal model with no visual unimportant features like nested or overlapping geometries or unwanted cracks. The voxelization process is the key part of the reparation process. We discuss implementation details and essential problems of ray-stabbing not addressed by Nooruddin and Turk 14. We focus on the generation of the volume model utilizing OpenGL hardware support. The current implementation is a snapshot of an ongoing work at EADS Airbus, Europes leading commercial aircraft company. The final goal is a fast model repair and reduction workflow for generating VR-models and various levels of detail. Problems erase from the fact, that the polygonalization of the volume model using the MC-algorithm generates a far too fine tessellated model which then has to be reduced again. We also discuss possible approaches to overcome this drawback.