06268859 is referenced by 110 patents and cites 8 patents.

Objects in an image are rendered in a manner which dynamically avoids the rendering of obscured objects. Data pertaining to one object is stored in a designated memory location, such as a cache memory. Data for a subsequent object is compared with the stored data, and the area of intersection between the two objects is determined. This area of intersection is subtracted from the first object, and the data for the second object is added to the memory. As the memory is filled, the data for the oldest object is removed and the object is rendered. After all objects in the list have been processed in this manner, those which remain in the memory are also rendered, and removed from the memory. At each step of the process, the portions of an object which are obscured by later-generated objects are eliminated, and thereby unnecessary rendering of obscured objects is avoided.

Title
Method and system for rendering overlapping opaque graphical objects in graphic imaging systems
Application Number
8/473651
Publication Number
6268859 (B1)
Application Date
June 6, 1995
Publication Date
July 31, 2001
Inventor
Kok S Chen
Sunnyvale
CA, US
Kevin W Andresen
Campbell
CA, US
Agent
Burns Doane Swecker & Mathis L
US
Assignee
Apple Computer
CA, US
IPC
G06T 15/40
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