Method and apparatus for providing sharp features on multiresolution subdivision surfaces

摘要

A method for representing a sharp feature on a surface of a model comprises the steps of defining at least one feature curve on the surface; reparameterizing the surface; and creating the feature on the reparameterized surface so as to be generally coincident with the feature curve, where the feature lies along boundaries between piecewise-smooth patch surfaces where patch surfaces with distinct tangent planes are joined. The surface is reparameterized by moving a control mesh relative to the surface to sample the feature curve with vertices of the control mesh, and creating the feature includes a subdivision step where edges and diagonals are treated as creases in the control mesh, and piecewise-smooth subdivision rules are applied to obtain a sharp feature on the surface. The surface may be defined in a Catmull-Clark multiresolution subdivision surface representation.