The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 22, 1993
Filed:
Mar. 14, 1990
Roger W Swanson, Fort Collins, CO (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
A method and apparatus for interpolating pixels to be displayed on a display screen so as to account for the nonlinearity of distance changes in the perspective projection of a 3-D object onto the display for corresponding linear distance changes in 3-D world space. Each pixel of an input polygon to be displayed on the display screen is given a perspective value in world coordinates for each display point, and this value is passed through the graphics processor along with the shading parameters associated with the each display point. The respective shading parameters for each display point are then scaled by the perspective value for each display point to account for the effects of perspective foreshortening of the displayed object on the display screen. Since no translation to world coordinates is required for the perspective scaling, fast hardware circuitry may be used. The rendered image of the invention has much improved color accuracy since the shading more closely reflects the effects of changing perspective in world space.