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| United States Patent | 8,610,729 |
| Airey , et al. | December 17, 2013 |
A floating point rasterization and frame buffer in a computer system graphics program. The rasterization, fog, lighting, texturing, blending, and antialiasing processes operate on floating point values. In one embodiment, a 16-bit floating point format consisting of one sign bit, ten mantissa bits, and five exponent bits (s10e5), is used to optimize the range and precision afforded by the 16 available bits of information. In other embodiments, the floating point format can be defined in the manner preferred in order to achieve a desired range and precision of the data stored in the frame buffer. The final floating point values corresponding to pixel attributes are stored in a frame buffer and eventually read and drawn for display. The graphics program can operate directly on the data in the frame buffer without losing any of the desired range and precision of the data.
| Inventors: | Airey; John M. (Mountain View, CA), Peercy; Mark S. (Cupertino, CA), Drebin; Robert A. (Palo Alto, CA), Montrym; John (Los Altos Hills, CA), Dignam; David L. (Belmont, CA), Migdal; Christopher J. (Cupertino, CA), Loh; Danny D. (Menlo Park, CA) | ||||||||||
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| Applicant: |
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| Assignee: |
Graphic Properties Holdings, Inc.
(New Rochell,
NY)
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| Family ID: | 29418296 | ||||||||||
| Appl. No.: | 13/494,138 | ||||||||||
| Filed: | June 12, 2012 |
| Document Identifier | Publication Date | |
|---|---|---|
| US 20120249562 A1 | Oct 4, 2012 | |
| Application Number | Filing Date | Patent Number | Issue Date | ||
|---|---|---|---|---|---|
| 13397830 | Feb 16, 2012 | ||||
| 13004650 | Mar 27, 2012 | 8144158 | |||
| 12632262 | Dec 7, 2009 | ||||
| 12168578 | Jul 7, 2008 | ||||
| 09614363 | Apr 14, 2009 | 7518615 | |||
| 09098041 | Nov 18, 2003 | 6650327 | |||
| Current U.S. Class: | 345/519; 345/422; 345/502; 345/503; 345/506; 345/531; 345/543; 345/546; 345/552; 345/581; 345/582; 345/589; 345/592; 345/611; 345/634 |
| Current CPC Class: | G06T 1/20 (20130101); G06T 11/40 (20130101); G06T 15/00 (20130101); G06T 17/00 (20130101); G06T 15/00 (20130101); G06T 15/405 (20130101); G06T 15/405 (20130101); G06T 19/00 (20130101); G09G 5/393 (20130101); G06T 19/00 (20130101); G06T 17/00 (20130101) |
| Current International Class: | G06F 13/14 (20060101); G06T 1/20 (20060101) |
| Field of Search: | ;345/418-427,501-506,440-442,519,581-587 |
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