Patent ID: 7382369

Claim:
A method for enhancing a Precomputed Radiance Transfer (PRT) mesh comprising a tessellation of triangles, said triangles comprising vertices and edges, said method comprising: dividing at least one triangle in the mesh, but not all triangles in the mesh, into at least two or more triangles apiece, wherein said dividing at least one triangle comprises dividing at least one edge and creating at least one new vertex and at least one new edge running from said vertex for said triangle; sampling a PRT vector at each vertex and each midpoint of each edge, and computing an error at each midpoint at each edge based on the PRT vector for each said midpoint and the PRT vectors for each vertex corresponding to each said edge; and for each edge having an error at its midpoint that is greater than a predetermined error tolerance value (a “marked edge”), dividing the triangle for that edge into at least two new triangles as follows: dividing the marked edge into two new edges with a new vertex at the midpoint for said edge (each a “divided edge”); and creating a new edge between said new vertex and a vertex not on said edge, such that said edge is common to said two new triangles (each a “common edge”).