Method and apparatus for adaptive phong shading
CA 2045889 C · Owner: Mckeown, Jack R. · Inventors: Van Loo, James; Wells, Stuart; Bhakta, Mukund
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In the method and apparatus of the present invention an adaptive shading method is utilized to generate shaded images in real time. The color or, intensity is first computed at each of the vertices of the polygon. A series of, tests are then performed to determine the order equation that is to be used to interpolate the color or intensity across the polygon between the vertices. Using, this technique, polygons having a slight or no curvature and an infinite light source (thus being the simplest form of shading) will use an extremely fast, low, order equation to interpolate across the polygon. Polygons having a high, degree of curvature and/or positional light source will utilize as …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed June 28, 1991 and granted March 20, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 28, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 28, 2013.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.