Method, system, and computer program product for bump mapping in tangent space
US5949424A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 28, 1997 |
| Grant date | Sep 7, 1999 |
| Priority date | — |
| Expiry date | Feb 28, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T15/60
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method, system, and computer program product for accelerated shading of an object surface by bump mapping in tangent space. A tangent space transform module builds a tangent space transform matrix M(p) having elements comprised of normal, tangent, and binormal vector components determined at a surface point on the object surface. The tangent space transform module further transforms shading vectors, such as, lighting and viewing vectors, into a tangent space defined by the tangent space transform matrix and outputs corresponding tangent space shading vectors. A bump mapping module performs vector operations between one or more tangent space shading vectors and a perturbed normal N' in tangent space. A texture memory stores a surface dependent or a surface independent tangent space perturbed normal texture map. The lighting module computes a shading value for the surface point based on the vector operations. The shading value can be then be mapped to a pixel to shade the object surface rendered on a computer graphics display. The bump mapping module outputs diffuse and specular components. The diffuse component corresponds to a first dot product between a normalized, interpolated …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.