Patent ID: 6618047
Filing Date: 2003-09-09
Classification: G06T

Abstract:
A method of reducing the visibility related computations in 3-D computer graphics, the visibility related computations being performed on 3-D surfaces or their sub-elements, or a selected set of both, the method comprising:identifying grid cells which arc under or related to the projections or extents of projections associated with at least one of said 3-D surfaces or their sub-elements; comparing data associated with said at least one of 3-D surfaces or their sub-elements with stored data associated with the grid cells; determining which of said at least one of 3-D surfaces or their sub-elements is always invisible or always visible to a viewpoint or a group of viewpoints by projection based computations prior to a visibility computation; and ignoring said determined at least one of the 3-D surfaces or their sub-elements during said visibility computation.