Computer graphics processing and selective visual display system – Computer graphics processing – Attributes
Reexamination Certificate
2000-02-04
2002-02-12
Zimmerman, Mark (Department: 2671)
Computer graphics processing and selective visual display system
Computer graphics processing
Attributes
C345S597000, C345S619000
Reexamination Certificate
active
06346948
ABSTRACT:
BACKGROUND OF THE PRESENT INVENTION
1. Field of the Invention
This invention relates to the field of object-oriented computer graphics and imaging.
2. Background Art
In computer graphics applications there is a technique for combining two images known as “compositing”. One example of compositing is the blending of a new screen object of one color with an existing screen object of another color. This color blend is accomplished using a well known compositing technique known as alpha compositing, such as described by T. Porter and T. Duff, “Compositing Digital Images”, SIGGRAPH 84, pp. 253-259. A problem with current schemes for providing compositing in computer systems is a difficulty in adding different compositing techniques. Currently, available compositing schemes are hard coded algorithms and are often tied to specific hardware implementations. This discourages or prevents the addition of customized compositing schemes.
SUMMARY OF THE INVENTION
The present invention provides a method and apparatus that permits the introduction of customized compositing techniques into an application by a developer. A Composite interface and a CompositeContext interface are defined. Custom compositing operations can be defined by implementing these interfaces. A Composite object provides a CompositeContext object that holds the state and performs the compositing work. Multiple CompositeContext objects can be created from one Composite object to maintain separate states in a multi-threaded environment.
An object implementing the Composite interface can be set as rendering state on a graphics object that provides rendering methods. This allows arbitrary compositing rules to be used by a developer. In one implementation of the Composite and CompositeContext interfaces, an AlphaComposite class is defined. The AlphaComposite class implements common compositing rules, such as defined by Porter and Duff, for combining source and destination pixels to achieve blending and transparency effects with graphics and images.
REFERENCES:
patent: 5291585 (1994-03-01), Sato et al.
patent: 5335320 (1994-08-01), Iwata et al.
patent: 5345550 (1994-09-01), Bloomfield
patent: 5347627 (1994-09-01), Hoffmann et al.
patent: 5384911 (1995-01-01), Bloomfield
patent: 5412772 (1995-05-01), Monson
patent: 5414806 (1995-05-01), Richards
patent: 5423034 (1995-06-01), Cohen-Levy et al.
patent: 5430836 (1995-07-01), Wolf et al.
patent: 5436637 (1995-07-01), Gayraud et al.
patent: 5448695 (1995-09-01), Douglas et al.
patent: 5461399 (1995-10-01), Cragun
patent: 5461710 (1995-10-01), Bloomfield et al.
patent: 5473745 (1995-12-01), Berry et al.
patent: 5491784 (1996-02-01), Douglas et al.
patent: 5493638 (1996-02-01), Hooper et al.
patent: 5509116 (1996-04-01), Hiraga et al.
patent: 5526517 (1996-06-01), Jones et al.
patent: 5544288 (1996-08-01), Morgan et al.
patent: 5546519 (1996-08-01), Berry
patent: 5548702 (1996-08-01), Li et al.
patent: 5550968 (1996-08-01), Miller et al.
patent: 5559942 (1996-09-01), Gough et al.
patent: 5564003 (1996-10-01), Bell et al.
patent: 5566330 (1996-10-01), Sheffield
patent: 5570462 (1996-10-01), McFarland
patent: 5572643 (1996-11-01), Judson
patent: 5638499 (1997-06-01), O'Connor et al.
patent: 5638502 (1997-06-01), Murata
patent: 5652851 (1997-07-01), Stone et al.
patent: 5694603 (1997-12-01), Reiffin
patent: 5694604 (1997-12-01), Reiffin
patent: 5740343 (1998-04-01), Tarolli et al.
patent: 5745121 (1998-04-01), Politis
patent: 6034694 (2000-03-01), Evans et al.
patent: 6130676 (2000-10-01), Wise et al.
Ronald L. Johnston, “The Dynamic Incremental Compiler of APL/3000” Proceedings of the API '79 Conference, published as APL Quote Quad, 9(4), p 82-87.
Leo J. Guibas et al., “Compilation and Delayed Evaluation in APL,” Fifth Annual Synposium on Principles in Programming Languages, p 1-8, 1978.
Gleen Krasner “The Smalltalk-80 Virtual Machine” BYTE Publications Inc., Aug. 1991, pp 300-320.
Thomas Porter et al. “Compositing Digital Images” Association for Computing Machinery (ACM), 1984, pp. 253-259.
Evans Jerald
Graham James
Nguyen Thanh
Cao Hoedung X.
Sun Microsystems Inc.
The Hecker Law Group
Zimmerman Mark
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