DiagSplit: Parallel, Crack-free, Adaptive Tessellation for Micropolygon Rendering

We present DIAGSPLIT, a parallel algorithm for adaptively tessellating displaced parametric surfaces into high-quality, crack-free micropolygon meshes. DIAGSPLIT modifies the split-dice tessellation algorithm to allow splits along non-isoparametric directions in the surface's parametric domain, and uses a dicing scheme that supports unique tessellation factors for each subpatch edge. Edge tessellation factors are computed using only information local to subpatch edges. These modifications allow all subpatches generated by DIAGSPLIT to be processed independently without introducing T-junctions or mesh cracks and without incurring the tessellation overhead of binary dicing. We demonstrate that DIAGSPLIT produces output that is better (in terms of image quality and number of micropolygons produced) than existing parallel tessellation schemes, and as good as highly adaptive split-dice implementations that are less amenable to parallelization.