Computer graphics processing and selective visual display system – Computer graphics processing – Graph generating
Reexamination Certificate
1994-02-28
2001-07-03
Nguyen, Phu K. (Department: 2671)
Computer graphics processing and selective visual display system
Computer graphics processing
Graph generating
Reexamination Certificate
active
06256042
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method and apparatus for displaying graphics on a display device, for use in a system, such as a computer-aided design (CAD) system, that displays many graphic items on a display device. More particularly, the invention relates to a method and apparatus for displaying graphics on a display device in a multi-window environment.
2. Description of the Related Art
Application programs implementing a CAD system generate a large number of graphic elements such as lines with their attributes, including color and line width, specified, and display the generated graphic elements sequentially on a display device Display of a graphic element is accomplished by sending to a display device a command that specifies the attributes of the graphic element, and a graphic drawing command with the coordinates of the graphic element specified.
In the multi-window environment, since screen redraw requests are generated at frequent intervals, it is required that the screen, including the many graphic elements already generated, be output at once onto the display device in the shortest possible time. To achieve this, a graphic management facility for managing graphic information is provided between the application program and the display device. The graphic management facility receives graphic element data, including data specifying, for example, color, line width, etc., from the application program, and stores them into memory. When a draw request is input from the operating system (OS) or application program, the stored data are retrieved, and screen drawing is performed by sending an attribute specifying command and a draw command to the display device accordingly. At this time, instead of outputting an attribute specifying command prior to a draw command each time the command is invoked, the graphic management facility outputs an attribute specifying command only when the attributes of the graphic element to be output are different from those of the previously output graphic element. This is necessary to finish the drawing process in the shortest possible time.
The graphic management facility is delivered, for example, in the form of a library containing a large number of subroutines. When generating an execution module for an application program, the subroutines needed by the application program are fetched into the execution module.
Such a graphic management facility has contributed to drastically reducing the length of time required from the input of a draw request until the drawing process is completed. However, the above-described graphic management facility requires that the attribute data be compared each time the graphic element data are retrieved from memory. When processing a large number of line drawing data generated in a CAD system, the length of time required for the comparison of data cannot be neglected. This has been a major obstacle to speeding up the drawing process.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a graphic display method and an apparatus, which overcome the shortcomings of the prior art graphic management facility and are capable of displaying many graphic elements in a much shorter time than the prior art has been able to achieve.
According to the present invention, there is provided a graphic display method comprising the steps of: generating data of graphic elements having a plurality of attributes; classifying the generated graphic element data into groups according to the attributes thereof and storing the same into memory: and displaying the graphic element data stored in memory onto a display device, one group at a time.
According to the present invention, there is also provided a graphic display apparatus comprising: means for generating data of graphic elements having a plurality of attributes; means for classifying the generated graphic element data into groups according to the attributes thereof and for storing the same into memory; and means for outputting the graphic element data stored in memory onto a display device, one group at a time.
REFERENCES:
patent: 4847788 (1989-07-01), Shimada
patent: 5133052 (1992-07-01), Bier et al.
patent: 5257349 (1993-10-01), Alexander
patent: 5293469 (1994-03-01), Outa et al.
Fujitsu Limited
Nguyen Phu K.
Staas & Halsey , LLP
LandOfFree
Graphic display method and apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Graphic display method and apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Graphic display method and apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2462811