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:
Feb. 20, 1996
Filed:
Sep. 15, 1993
Gavin S Miller, Palo Alto, CA (US);
Apple Computer, Inc., Cupertino, CA (US);
Abstract
A system for shading graphic images for realistic rendering representative of tarnish accumulation has a display device, a central processing unit, an input device, and a memory means. The memory includes image components, shading routines, accessibility routines, display routines, and a texture map. The system modifies each image prior to display to apply shading. The system uses the accessibility routines to produce an accessibility factor for each pixel in the image. The accessibility factor is then used by the display routines to apply the desired shading to each pixel as it is rendered on the display device. A method for producing an accessibility factor and determining the amount of shading applied to a pixel includes the steps of: identifying a surface and point corresponding to the pixel; identifying another object that affects the accessibility; determining the type of the other object; calculating the radius of a sphere tangent to both the point and the object; and setting the accessibility factor equal to the radius of the sphere. This process is then repeated for each object in the image. The minimum accessibility factor for all tested objects is determined, and then used by the present invention to apply the appropriate amount of shading to the pixel when it is rendered.