Compression of graphic data normals
US5736987A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 19, 1996 |
| Grant date | Apr 7, 1998 |
| Priority date | — |
| Expiry date | Mar 19, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T15/00
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Geometric data for a three-dimensional surface are compressed in regard to the data representing the continuity between triangles in a mesh that represents the three-dimensional surface. The geometric data include information defining the vertices of the triangles comprising the mesh, an indication of the triangle faces, and corner normals to each of the vertices shared by triangles having a common vertex, which indicates the continuity or discontinuity between adjacent triangles of the surface. Vertex rotation continuity (VRC) data are determined for each vertex shared by adjacent triangles, indicating whether the transition between the adjacent triangles is continuous or discontinuous. Further, a dihedral angle between each pair of adjacent triangles is determined and associated with the VRC bit. The VRC data are sorted by the associated dihedral angles, enabling an optimal dihedral angle to be selected. The optimal dihedral angle is chosen so as to minimize the number of errors in predicting the nature of the transition between adjacent triangles based on the dihedral angle between the adjacent triangle. Next, exception data are generated by comparing the dihedral angle for each…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.