Some objects have sharp geometric features such as corners and creases.
These features must however be completely contained in, or coincident with, a collection of edges or faces of the supporting mesh. We start by extracting, as in our previous algorithm, a two-manifold from the Delaunay triangulation of P . This fine mesh can be used to estimate dihedral angles between adjacent triangles and detect and tag sharp features. A mesh decimation algorithm is then applied to reduce the number of triangles, especially in areas of small curvature. The reduced mesh is used as the base for a simplicial-hull construction.