JPS61205989A - Graphic display unit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a graphic display device such as a graphic C'R, T display, and the like.

B0 Summary of the Invention The present invention provides a graphic display device that bit-expands graphic information stored in a segment buffer into a frame buffer, and displays a graphic based on this bit expansion, which erases the graphic information displayed on the screen. By receiving a command and specifying an area where no graphic information stored in the segment buffer exists as the area to be displayed, it is possible to speed up the erasing of graphic information displayed on the screen. .

C0 Conventional technology Graphic CRT display devices have traditionally been manufactured using CAD, CA
Although they are mainly used in offline work such as creating and modifying figures in the fields of M, OA, E, etc., their use as terminal devices for online systems has recently increased. This graphic 0RTfi display device as an online/system terminal device is required to have the following two points in terms of functionality and performance compared to the previous ones.

(1) High-speed display: Good responsiveness is an essential condition for an online system, and the process from display request to display completion must be performed at high speed, and the display of valley rice must be updated at high speed.

(2+ Support for wide area... Since the online system operates on equipment installed in a wide area, it must support a wide display area and be able to display the necessary range according to display requests.

In order to meet these demands, a system configuration called an intelligent terminal type has been adopted as a graphic display system.

As shown in FIG. 3, this system uses a graphic CRT display device #1 with a computer as a terminal side, and a host computer system 2 is connected to this terminal side via a communication line. An online system is constructed by connecting to a terminal device or a host computer. In this configuration, a distributed processing system is used in which the host computer system 2 performs a large amount of arithmetic processing or data processing, and the terminal-side graphic CRT display computer performs the disk V processing. The load on the host computer system 2 is also reduced while improving performance.

The graphic display process in the configuration shown in FIG. 3 will be described in detail below.

The graphic CRT display device 1 has a refresh drawing 1-rcRT monitor 3 using a rask scan display method, a display processor 4 as a control center, and a graphic CRT display device 1 that uses a display processor 4 to display information such as graphics (line segments, symbols, characters, etc.). )
is stored in the segment buffer 5I. Segment buffer 5. As shown in the logical relationship shown in Figure 4, the graphical information stored in S
It is configured in a tree structure by l:l and an attribute element sp that is located above these graphic elements SD and defines attributes (visible attributes, detected attributes, etc.) of each graphic element.

This segment buffer 5. From the graphic information stored within, the graphic information in the range (rectangular area determined by the coordinate values) requested to be displayed is cut out. This cutting process involves parallel translation and rotational transformation of the displayed figure.
Jx calculation processing unit 5. , a clipping processing unit 5 that removes portions of the CRT monitor 3 that extend beyond the displayable screen frame;
A digital differential analysis (T)DA) processing unit 54 further develops the cut out line segment of graphic information from the display position (coordinate position) into on/off information of the corresponding bit on the frame buffer 6. will be prepared.

The frame buffer 6 is physically a memory that has bits that correspond one-to-one to each pixel on the screen of the ORT monitor 3. For color display, the frame buffer 6 has multiple bit planes, and uses the lookup table 7. Decide the display color. This will be explained with reference to FIG. The figure shows frame buffer 6
is 3 bitplanes + 1. 2. +3, and the on/off state of the bit corresponding to the graphic information in the segment buffer 51 is developed as a combination of bit planes +1 to ◆3. %The display on the screen of the CRT monitor 3 is performed by raster scanning the frame buffer 6 and using the combination value of the bits on of valley bit plane + 1 to 4P3 as an address according to the display color table defined in the lookup table 7. R (red), G (green), B (
The output of each beam (blue) is given to the CRT monitor 3. The table below shows the strong display color difference 14) for each beam in the look-up table 7 for each bit planar 1 to ≠ 3 bit combination of the frame buffer 6 in terms of correspondence percentage.
Eight types of colors are specified for each pixel using three bit planes φ1 to φ3, and R of the lookup table 7 is used.
By applying 3 bits to each of the eG and 1llr beams, 512 (2') colors can be selected.

Returning to FIG. 3, the host computer system 2 has a host computer 8 as its control center.

As one of the processing functions of online processing, data subjected to graphic information processing is divided into appropriate formats and stored in an external storage device 19 such as a magnetic disk, and the graphic information within the range required by the graphic CR7 display device 1 is transferred to the interface. 10, 11, transmit to the graphic CR7 display device t1 through the communication line 12, and display the graphic C
In the R7 display device 1, the received data is stored in the segment buffer 51.

By the way, generally when switching the figure displayed on the screen of the monitor 3 to a new figure, the original figure displayed on the screen is once erased. The erasure described in this proposal does not mean erasure by deleting the graphic information in the segment buffer, but rather the graphic information in the segment buffer remains registered and is erased on the screen (frame buffer). Refers to something to do. Therefore, it is possible to redisplay the graphic information without registering it.

Conventionally, when performing such erasure, segment buffer 5. By turning off the visibility attribute of the segment structure within, the graphic information that is already displayed is bit-expanded to the frame buffer so that it becomes the background color, and the graphic information is displayed in the background color. Ta.

Problems to be solved by the D0 invention However, if such processing were performed when displaying a new graphic, bit expansion would have to be performed in the frame buffer each time, and the processing required for this would be This has the disadvantage that the processing is almost the same as that for displaying, and therefore the processing is slow.

The present invention was made under these circumstances,
It is an object of the present invention to provide a graphic display device that can instantly erase graphic information displayed on a screen and speed up switching processing of the I[1ii plane.

Means and operation for solving the E0 problem The present invention specifies an area where no graphic information stored in a segment buffer exists as an area to be displayed in response to an instruction to erase graphic information displayed on a screen. Further, an erasing unit is provided that turns off the visible attribute of the segment structure of the graphic information to be erased in the segment buffer and erases at once bit signals corresponding to the graphic information already stored in the frame buffer. Become. Therefore, all figure information A
is being displayed on the screen, and when the erasing section receives a command to erase this graphic information A, the bit signals corresponding to the graphic information mA stored in the frame buffer are erased at once.

Then, the visibility attribute of the segment structure of graphic information A is turned off.

Since an area where no graphic information stored in the segment buffer exists is specified as the display target area, graphic information A does not exist in this area, so it is excluded from the processing target by clipping processing, and background color drawing is not performed. .

F. Example The present invention will be explained in detail below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention. In the figure, 13 is a main control unit, and segment buffer 5. This is the part that controls when performing processing such as constructing graphic information as a segment structure within the frame, turning on the visibility attribute of the segment structure, and expanding bits into the frame buffer. In the figure, 55.6 is the same part as the part with the same reference numeral in FIG.

A clipping processing unit and a frame buffer are shown respectively.

Reference numeral 14 denotes an erasing section, which receives an instruction to erase the graphic information displayed on the screen from the main control section 13, and erases the area S1 containing all the graphic information stored in the segment buffer 51 as shown in FIG. Area S away from! is designated as the display target area, and the designation command is sent to the clipping processing section 53. Further, the erasing unit 14 turns off the visibility attribute of the segment structure of the graphic information to be erased in the segment buffer 5I, and also
It has the function of erasing all bit signals corresponding to the graphic information stored in the memory at once. Therefore, drawing to the frame buffer 6 is performed on bit planes Φ1 to Φ1 according to the graphic information.
In step 3, bit expansion is performed using a combination of rlJ and rOJ, and the erasing unit 14 erases all "1" signals stored in each bit plane +1 to +3.
O”. Therefore, by setting the background color beam to be emitted when the bit combinations of bit planes 1 to 3 are rO, O, OJ, all the graphic information displayed on the screen is erased. The reason why the visibility attribute is turned off here is that if it were to remain on, when a new graphic is displayed on the screen, the previously displayed graphic information would be displayed again.

When a display target area is specified, the clipping processing unit 5° cuts out the graphic information included in the area, and draws the cut out graphic in the frame buffer 6 by bit expansion. This clipping process is started by turning on or off the visibility attribute of the segment structure. For example, when the visibility attribute is turned off, the graphic information to be erased is cut out and displayed in the background color, but only one display object If graphic information does not exist within the area, it is excluded from the processing target by clipping processing, and therefore, the bit expansion processing that normally follows is not performed. When this embodiment is used in the system shown in FIG.
It is configured to be distributed between the side and the graphic CR7 display device 11 side.

Next, the operation when the embodiment shown in FIG. 1 is applied to the system shown in FIG. 3 will be described. First, from the host computer system 2 to the segment buffer 5 of the graphic CR7 display device 1. Predetermined graphic information is stored in advance. Now, when the host computer 8 issues an instruction to display the graphic information @l,it.

For the graphic CR7 display device 1, graphic information 1.
If you specify the area containing II as the display target area (the corresponding area in S1), the graphic CRT
Display device costs 1 yen.

According to the display command of the processor 4, the segment buffer 5.
The visibility attributes related to the figures @l and II inside are turned on.

As a result, the bit plane of frame buffer 6 ÷ 1 ~
The bits corresponding to the graphic information at and n are expanded to the motor 3, and the graphic information 1. It is displayed. If you want to delete figure information 1.1 and display new figure information here,
When an erase command is input to the host computer 8, the area S where no graphic information stored in the segment buffer 5I exists is designated as the area to be displayed, and the host computer 8 sends the graphic CRT display device 1
A signal for specifying area S and erasing command is sent within.

The erasing unit 14 on the side of the graphic CRT display device 1 receives the erasing command and erases the graphic information 1 of the segment buffer 51 yen.
．． The visual attribute related to (2) is turned off, and the signals "1" stored in bit planes φ1 to φ3 are all set to rOJ at once. - A designation signal for area S is input to the clipping processing unit 53, but since graphic information I, ■ does not exist in area S, clipping occurs even if the visual attribute related to graphic information Il■ is turned off. The processing target is excluded from the processing, and accordingly, bit development related to drawing the background color to the frame buffer 6 is not performed. This result figure information 1
．． it is instantly set to the background color and erased from the screen. Thereafter, graphical information to be newly displayed is displayed on the screen in the same manner.

G0 Effects of the Invention As described above, when erasing an entire screen, the present invention erases the bit signals of the frame buffer at once, and also specifies the area where no graphic information stored in the segment buffer exists as the display target. Because of this,
The subsequent processing associated with turning off the visible attribute is no longer subject to internal processing, and as a result, background color drawing processing using bit expansion is not performed.

Therefore, graphic information can be deleted instantly.

It is possible to speed up the screen switching process.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing an embodiment of the present invention, FIG. 2 is an explanatory diagram showing the display target area specified by the erasing section, and FIG. 3 is a graphic CRT display device as a graphic display device and a host computer system. FIG. 4 is an explanatory diagram showing the structure of graphic information stored in a segment buffer, and FIG. 5 is an explanatory diagram schematically showing the processing stages of graphic information. 1... Graphic CRT device, 2... Host computer system, 3... CRT monitor, 4... Display processor as a control center, 5. ... segment buffer, 5. ... Clipping processing section, 6
. . . Frame buffer, 7. Lookup table, 8. Host computer, 13. Main control unit, 14. Eraser.

Claims (1)

[Claims] Graphic information is constructed and stored as a segment structure in a segment buffer, and from among the stored graphic information, a clipping processing unit cuts out graphic information included in a designated display target area and creates a frame. In a graphics display device that draws by expanding bits into a buffer, in response to an instruction to erase graphic information displayed on the screen, an area where graphic information stored in a segment buffer circle does not exist is set as the display target area. An erasing unit is provided that turns off the visible attribute of the segment structure of the specified graphic information to be erased in the segment buffer, and erases at once the bit signals corresponding to the graphic information already stored in the frame buffer. A graphic display device characterized by: