Patent US3639736A successfully refreshed from Google Patents.
US3639736A
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Assignee: Individual
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Filing: 1969-11-19
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Granted: 1972-02-01
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Expires: 1989-11-19
Abstract
Abstract A computation system is disclosed, as for interpolating lines with specific application to the selection of a portion of a line which is to be presented in a fragmentary display. The system as disclosed eliminates those portions of lines that are contained within a drawing (as defined in computer storage) which lie outside a rectangular ''''window'''' (defining a portion of the drawing) by computing vector coordinates for the terminal ends (start and end) of the visible portions of each such lines. The described embodiment utilizes a binary system of shifting coordinate differential data to clip and divide the lines which are defined by their end points. Repetitive operations attain the desired definition.
Inventors
- 👤 Ivan E Sutherland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:13
CPC Classifications
G; G09; G09G; G09G1/00; G09G1/06; G09G1/08; G06; G06T; G06T15/00; G06T15/10
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
106 words
A computing system comprising: a first register means for registering representations of vector coordinates for a first point; a second register means for registering representations of vector coordinates for a second point; means for computing signals representative of vector coordinates defining an interim point which is a linear combination of said first and second points; means for transferring said signals representative of vector coordinates defining an interim point to one of said register means to replace the prior contents of said register means; and means for controlling said means for transferring, in accordance with signals, including said signals representative of vector coordinates of an interim point.
Claim 2
Dependent Claim
106 words
A computing system comprising: a first register means for registering representations of vector coordinates for a first point; a second register means for registering representations of vector coordinates for a second point; means for computing signals representative of vector coordinates defining an interim point which is a linear combination of said first and second points; means for transferring said signals representative of vector coordinates defining an interim point to one of said register means to replace the prior contents of said register means; and means for controlling said means for transferring, in accordance with signals, including said signals representative of vector coordinates of an interim point.
Claim 3
Dependent Claim
48 words
A computing system according to claim 1 wherein said means for controlling said means for transferring said signals representative of vector coordinates of an interim point includes, a logic circuit connected to receive signals indicative of the signs of said vector coordinates to control said means for transferring.
Claim 4
Dependent Claim
83 words
A computing system according to claim 1, wherein said vector coordinates represented in said first and second register means are signed quantities and the signs thereof are registered in said first and second registers and wherein said means for computing signals comprises means for computing signals representative of vector coordinates, including signs therefor and wherein said means for controlling said means for transferring is connected to be controlled by signals representative of the signs of coordinates including said coordinates of an interim point.
Claim 5
Dependent Claim
37 words
A computing system according to claim 3 further including control means connected to said register means, to cyclically operate said means for computing whereby to define the coordinate end points of a line within a predetermined area.
Claim 6
Dependent Claim
27 words
A computing system according to claim 3 wherein said vector coordinates are specified by four values, whereby said first and second register means each register four coorDinates.
Claim 7
Dependent Claim
27 words
A computing system according to claim 3 further including means for registering coordinates defining at least four references to which said coordinates for said points are referenced.
Claim 8
Dependent Claim
20 words
A computing system according to claim 1 wherein said means for computing includes adder means and digital shift register means.
Claim 9
Dependent Claim
91 words
A process of machine computing, comprising the steps of: defining vector coordinates for a first point in machine language; defining vector coordinates for a second point in machine language; machine computing vector coordinates of an interim point which lies in linear relationship with said first and second points; and treating said vector coordinates of an interim point as the coordinates to selectively replace one of said vector coordinates for a first point or a second point and repeating said computing step to finally define a pair of coordinates within predetermined limits.
Claim 10
Dependent Claim
91 words
A process of machine computing, comprising the steps of: defining vector coordinates for a first point in machine language; defining vector coordinates for a second point in machine language; machine computing vector coordinates of an interim point which lies in linear relationship with said first and second points; and treating said vector coordinates of an interim point as the coordinates to selectively replace one of said vector coordinates for a first point or a second point and repeating said computing step to finally define a pair of coordinates within predetermined limits.
Claim 11
Dependent Claim
18 words
A process according to claim 8 wherein in said steps of defining said points, four-value coordinates are utilized.
Claim 12
Dependent Claim
19 words
A process according to claim 9 wherein said points are defined and computed in a binary system of numbers.
Claim 13
Dependent Claim
20 words
A process according to claim 9 wherein said coordinates are referenced to four reference levels definitive of a rectangular configuration.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-31 | 1975-08-02 | 1976-02-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-31 | 1979-08-02 | 1980-02-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-31 | 1983-08-02 | 1984-02-01 | $7700.00 | Window Closed / Lapsed |