Patent ID: 7295204
Filing Date: 2007-11-13
Classification: G06T

Abstract:
1. A method for rendering bicubic surfaces of an object on a computer system, at least a portion of the surfaces defined by sixteen control points and bounded by four boundary curves, each corresponding to an edge, wherein each boundary edge is formed by a boundary box of line segments formed between four control points, and wherein at least one surface shares one of the boundary edges with a second surface, the method comprising: (a) transforming only the control points of the surface given a view of the object; (b) using the four boundary edges for purposes of subdivision; (c) selecting an additional pair of orthogonal internal curves to process; (d) iteratively subdividing the four boundary edges and the pair of orthogonal internal curves in screen coordinates, wherein two new curves are generated with each subdivision; (e) performing a new subdivision on each of the four boundary edges and the two orthogonal internal curves for each new view in screen coordinates, wherein the subdivision of the four boundary curves ensures continuity along the shared boundary edge; (f) terminating the subdivision of each of the curves when the curves satisfy a flatness threshold expressed in screen coordinates, thereby minimizing a number of computations required to render the object; and (g) storing the rendered object in a memory.