US4821209A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Data transformation and clipping in a graphics display system
Assignee: International Business Machines Corp
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Filing: 1986-01-21
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Granted: 1989-04-11
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Expires: 2006-01-21
Abstract
Abstract A display processor in a raster graphics display system includes a transformation, clipping and mapping feature which controls the transformation, clipping and mapping of graphics data. A control byte contains 5 bits identified as: M--Window to viewport mapping; P--perspective projection; D--2D/3D mode; T--transformation; and C--clipping. Each bit in the control byte is tested to determine what operations are to be performed on the figure to be drawn.
Inventors
- 👤 Bruce C. Hempel
- 👤 Bob C. Liang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:35
CPC Classifications
G; G06; G06T; G06T15/00; G06T15/10; G06T15/30
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
169 words
A display processor for selectively providing transformation, clipping and mapping processes in a graphics display system comprising, in combination; a plurality of registers for storing branch addresses relating to said transformation, clipping and mapping processes; one of said registers being associated with each of said processes, means for branching to the value of one of said registers in accordance with the process being performed; means for determining the dimensions of a figure to be displayed; means for determining whether said figure is to be transformed; means for providing transformation of said figure; means for determining whether said figure is to be clipped against a predetermined clipping enclosure; means responsive to said last named determining means for clipping said figure against said predetermined clipping enclosure; and means for drawing said figure as a series of vectors for display on a display device in said graphic display system whereby the control decision for selective transformation, clipping and mapping processes is performed only when the transformation, clipping and mapping parameters are modified.
Claim 2
Dependent Claim
169 words
A display processor for selectively providing transformation, clipping and mapping processes in a graphics display system comprising, in combination; a plurality of registers for storing branch addresses relating to said transformation, clipping and mapping processes; one of said registers being associated with each of said processes, means for branching to the value of one of said registers in accordance with the process being performed; means for determining the dimensions of a figure to be displayed; means for determining whether said figure is to be transformed; means for providing transformation of said figure; means for determining whether said figure is to be clipped against a predetermined clipping enclosure; means responsive to said last named determining means for clipping said figure against said predetermined clipping enclosure; and means for drawing said figure as a series of vectors for display on a display device in said graphic display system whereby the control decision for selective transformation, clipping and mapping processes is performed only when the transformation, clipping and mapping parameters are modified.
Claim 3
Dependent Claim
21 words
Apparatus according to claim 1, further comprising: means for determining whether said figure is to be displayed as a perspective view.
Claim 4
Dependent Claim
31 words
Apparatus according to claim 1, further comprising: means for determining whether said figure is to be mapped to a view port; and means for mapping said figure to said view port.
Claim 5
Dependent Claim
18 words
Apparatus according to claim 1 wherein each of said plurality of determining means comprises input data responsive means.
Claim 6
Dependent Claim
19 words
Apparatus according to claim 1 wherein said means for transforming, clipping and drawing said figure comprise microcode control means.
Claim 7
Dependent Claim
117 words
In a graphics display system, a method for selectively controlling tranformation, clipping, mapping and drawing of a figure comprising the steps of: determining the dimensions of a figure to be displayed; determining whether said figure is to be transformed; determining whether said figure is to be clipped against a predetermined clipping enclosure; determining whether said figure is to be mapped; said determining steps being performed whenever the associated operations are specified; in an attributed register; and selectively transforming, clipping, mapping and drawing vector coordinates of said figure to be mapped without any other than with only the original specified condition of the said determining steps whenever a command to draw vector coordinates of said figure is executed.
Claim 8
Dependent Claim
117 words
In a graphics display system, a method for selectively controlling tranformation, clipping, mapping and drawing of a figure comprising the steps of: determining the dimensions of a figure to be displayed; determining whether said figure is to be transformed; determining whether said figure is to be clipped against a predetermined clipping enclosure; determining whether said figure is to be mapped; said determining steps being performed whenever the associated operations are specified; in an attributed register; and selectively transforming, clipping, mapping and drawing vector coordinates of said figure to be mapped without any other than with only the original specified condition of the said determining steps whenever a command to draw vector coordinates of said figure is executed.
Claim 9
Dependent Claim
23 words
A method according to claim 6, further comprising the step of: determining whether said figure is to be displayed as a perspective view.
References Cited (Backward Citations)
US4449201A
Cited
US4631690A
Cited
US4645459A
Cited
US4667190A
Cited
US4623880A
Cited
US4642790A
Cited
US4679038A
Cited
US4646075A
Cited
US4625289A
Cited
US4651278A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-04-10 | 1992-10-10 | 1993-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-04-10 | 1996-10-10 | 1997-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-04-10 | 2000-10-10 | 2001-04-11 | $7700.00 | Window Closed / Lapsed |