Out of core construction of patch trees

Current Level of Detail (LoD) approaches for triangle meshes use variably triangulated mesh patches, in order to approximate the original mesh surface. The approximation is synthesized from some of these patches, which must cover the whole surface and must not intersect each other. The patches are chosen according to the necessary view dependent triangulation. This paper addresses the creation of the required hierarchical data structures, in order to enable Level of Detail synthesis for very large triangle meshes. Because of the limited amount of internal memory, most of the mesh data reside in external memory during the process. Due to the high access latency of external memory, commonly used algorithms for small meshes are hardly applicable for so called “Out of Core” meshes. Other methods have to be found, which overcome the problems with the external memory.