US4698779A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Graphic display with determination of coincidence of subject and clip areas
Assignee: International Business Machines Corp
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Filing: 1985-04-30
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Granted: 1987-10-06
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Expires: 2005-04-30
Abstract
Abstract A method of determining the coincidence of a subject area and a clip area in a graphic display system, comprising creating three parts list, one for parts of the subject area that are outside the clip area, a second for parts of the clip area that are inside the subject area and a third for overlapping lines. The parts of the subject area which lie outside the clip area are defined by examining the parts lists. The output can then be used to control a pen plotter, in which different colors are used so that underlying areas do not have to be linked over with overlay colors.
Inventors
- 👤 Ian Holden
- 👤 Michael J. Malings
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 02:37
CPC Classifications
G; G06; G06T; G06T15/00; G06T15/10; G06T15/30; G06K; G06K15/00; G06K15/22; G09; G09G; G09G5/00; G09G5/42
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
240 words
A method of determining the coincidence of a subject area and a clip area, in a graphic display system in which area definitions are stored in a display list store comprising the steps of: (a) creating and storing a subject area parts list comprising separate entries for each part of one or more contiguous lines of the subject area that do not pass through the clip area (b) creating and storing a clip area parts list comprising separate entries for each part of one or more contiguous lines of the clip area that pass through the subject area (c) creating and storing an overlap parts list comprising separate entries for each part of one line of the subject and clip areas that overlap (d) for each entry in the subject area parts list scanning unprocessed entries first in the subject area parts list secondly in the clip area parts list thirdly in the overlap parts list for any entry having an end point definition the same as on end point definition of the part being processed, creating a new part by joining any part found to the part being processed storing the created part in a results part list and reiterating the process for the entry in the results part list until no further parts are found whereby the results part list includes the definition of the portion of the subject area which does not coincide with the clip area.
Claim 2
Independent Claim
240 words
A method of determining the coincidence of a subject area and a clip area, in a graphic display system in which area definitions are stored in a display list store comprising the steps of: (a) creating and storing a subject area parts list comprising separate entries for each part of one or more contiguous lines of the subject area that do not pass through the clip area (b) creating and storing a clip area parts list comprising separate entries for each part of one or more contiguous lines of the clip area that pass through the subject area (c) creating and storing an overlap parts list comprising separate entries for each part of one line of the subject and clip areas that overlap (d) for each entry in the subject area parts list scanning unprocessed entries first in the subject area parts list secondly in the clip area parts list thirdly in the overlap parts list for any entry having an end point definition the same as on end point definition of the part being processed, creating a new part by joining any part found to the part being processed storing the created part in a results part list and reiterating the process for the entry in the results part list until no further parts are found whereby the results part list includes the definition of the portion of the subject area which does not coincide with the clip area.
Claim 3
Dependent Claim
35 words
A method as claimed in claim 1 in which the graphic display system includes an output pen plotter and the result parts list is used to control the plotter when the subject area is drawn.
Claim 4
Dependent Claim
253 words
A graphic display system, in which complex area definitions are stored in a display list buffer, including control means adapted to control the operation of the system to perform the method of determining the coincidence of a subject area and a clip area comprising the steps of: (a) creating and storing a subject area parts list comprising separate entries for each part of one or more contiguous lines of the subject area that do not pass through the clip area (b) creating and storing a clip area parts list comprising separate entries for each part of one or more contiguous lines of the clip area that pass through the subject area (c) creating and storing an overlap parts list comprising separate entries for each part of one line of the subject and clip areas that overlap (d) for each entry in the subject area parts list scanning unprocessed entries first in the subject area parts list secondly in the clip area parts list thirdly in the overlap parts list for any entry having an end point definition the same as on end point definition of the part being processed, creating a new part by joining any part found to the part being processed storing the created part in a results part list and reiterating the process for the entry in the results part list until no further parts are found whereby the results part list includes the definition of the portion of the subject area which does not coincide with the clip area.
Claim 5
Dependent Claim
253 words
A graphic display system, in which complex area definitions are stored in a display list buffer, including control means adapted to control the operation of the system to perform the method of determining the coincidence of a subject area and a clip area comprising the steps of: (a) creating and storing a subject area parts list comprising separate entries for each part of one or more contiguous lines of the subject area that do not pass through the clip area (b) creating and storing a clip area parts list comprising separate entries for each part of one or more contiguous lines of the clip area that pass through the subject area (c) creating and storing an overlap parts list comprising separate entries for each part of one line of the subject and clip areas that overlap (d) for each entry in the subject area parts list scanning unprocessed entries first in the subject area parts list secondly in the clip area parts list thirdly in the overlap parts list for any entry having an end point definition the same as on end point definition of the part being processed, creating a new part by joining any part found to the part being processed storing the created part in a results part list and reiterating the process for the entry in the results part list until no further parts are found whereby the results part list includes the definition of the portion of the subject area which does not coincide with the clip area.
Claim 6
Dependent Claim
33 words
A graphic display system as claimed in claim 3 including an output pen plotter and in which the results part list is used to control the plotter when the subject area is drawn.
Claim 7
Dependent Claim
231 words
In a graphic display system a process for determining the coincidence of complex areas comprising for each subject area and clip area the steps of: (a) creating and storing a subject area parts list comprising separate entries for each part of one or more contiguous lines of the subject area that do not pass through the clip area (b) creating and storing a clip area parts list comprising separate entries for each part of one or more contiguous lines of the clip area that pass through the subject area (c) creating and storing an overlap parts list comprising separate entries for each part of one line of the subject and clip areas that overlap (d) for each entry in the subject area parts list scanning unprocessed entries first in the subject area parts list secondly in the clip area parts list thirdly in the overlap parts list for an entry having an end point definition the same as on end point definition of the part being processed, creating a new part by joining any part found to the part being processed storing the created part in a results part list and reiterating the process for the entry in the results part list until no further parts are found whereby the results part list includes the definition of the portion of the subject area which does not coincide with the clip area.
Claim 8
Dependent Claim
231 words
In a graphic display system a process for determining the coincidence of complex areas comprising for each subject area and clip area the steps of: (a) creating and storing a subject area parts list comprising separate entries for each part of one or more contiguous lines of the subject area that do not pass through the clip area (b) creating and storing a clip area parts list comprising separate entries for each part of one or more contiguous lines of the clip area that pass through the subject area (c) creating and storing an overlap parts list comprising separate entries for each part of one line of the subject and clip areas that overlap (d) for each entry in the subject area parts list scanning unprocessed entries first in the subject area parts list secondly in the clip area parts list thirdly in the overlap parts list for an entry having an end point definition the same as on end point definition of the part being processed, creating a new part by joining any part found to the part being processed storing the created part in a results part list and reiterating the process for the entry in the results part list until no further parts are found whereby the results part list includes the definition of the portion of the subject area which does not coincide with the clip area.
Claim 9
Dependent Claim
31 words
A system as claimed in claim 5 including an output pen plotter and in which the results parts list is used to control the plotter when the subject area is drawn.
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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) | 1990-10-05 | 1991-04-06 | 1991-10-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-10-05 | 1995-04-06 | 1995-10-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-10-05 | 1999-04-06 | 1999-10-06 | $7700.00 | Window Closed / Lapsed |