Centroidal Voronoi tessellation based polycube construction for adaptive all-hexahedral mesh generation

Abstract

This paper presents a novel automatic polycube construction algorithm using centroidal Voronoi tessellation (CVT) based surface segmentation. Given a smooth surface triangle mesh, we segment triangles into six clusters in the surface normal space while satisfying the constraints of polycube construction. A bijective mapping between the input mesh and polycube surfaces is then built via a planar domain parameterization. We develop a new harmonic boundary-enhanced centroidal Voronoi tessellation (HBECVT) method by including local neighbouring information in the energy function. Improving upon the classic CVT method, the HBECVT algorithm can not only overcome the sensitivity to the initialization and noise, but also improve the segmentation results and the resulting polycubes by reducing non-monotone boundaries. Based on the constructed polycube, we then generate quality all-hexahedral (all-hex) meshes. The uniform all-hex mesh and volumetric T-mesh can be obtained through the octree subdivision and mapping. We can also generate adaptive all-hex meshes by extracting the dual mesh from a hybrid octree, which consists of polyhedral cells and each grid point is always shared by eight cells. Several examples are presented in this paper to show the robustness of our algorithms.