JPH024953B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a graphic display device such as a graphic CRT display device.

B. Summary of the Invention The present invention provides a graphic display device that specifies an area to be displayed from a wide range of input data as graphic information and displays a range corresponding to the designation. By using a size table to decide whether or not to display figures and the size of the figure, it is possible to display figures that are easy to see and meet the needs of the viewer when displaying a wide or narrow range. is possible,
Moreover, this is intended to speed up the processing.

C. Conventional technology Graphic CRT devices have traditionally been based on CAD,
They are mainly used for offline work such as creating and modifying figures in fields such as CAM and CAE, but recently their use as terminal devices for online systems has been increasing. Graphics as a terminal device for this online system
CRT display devices have more functionality than previous ones.
In terms of performance, the following two points are strongly required.

(1) High-speed display: Good responsiveness is an essential condition for online systems, and the process from display request to display completion must be performed quickly, and various display updates must also be performed quickly.

(2) Wide area support...Some online systems operate on equipment installed over a wide area. be able to display. (It must have a so-called computer mapping function.) To meet these demands, a system configuration called an intelligent terminal type has been adopted as a graphic display system. As shown in FIG. 2, in this system, a graphic CRT display device 1 with a computer is used 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 host computer. In this configuration, a distributed processing method is used in which the host computer system 2 performs a large amount of arithmetic processing or data processing, and the computer in the terminal-side graphic CRT display device 1 performs display processing, which improves responsiveness on the terminal side. While improving the host computer system 2
It also reduces the load on The graphic display process in the configuration shown in FIG. 2 will be described in detail below.

The graphic CRT display device 1 performs refresh drawing using a raster scan display method.
It has a CRT monitor 3, a display processor 4 as a control center, and graphic information (information such as line segment symbols, characters, etc.) to be displayed is stored in a segment buffer ₅₁ . The graphical information stored in the segment buffer 5 ₁ includes individual graphical elements located at the lowest level (data type, display position, display color, etc. that specifies the displayed graphic) SD, as shown in the logical relationship shown in Figure 3. and an attribute element SP that is positioned above these graphic elements SD and defines the attributes (visible attributes, detection attributes, etc.) of each graphic element.

From the graphic information stored in the segment buffer ₅₁ , graphic information in a range (rectangular area determined by coordinate values) required to be displayed is cut out. This cutting process includes a matrix calculation processing unit 5 ₂ that performs parallel translation and rotation transformation of the displayed figure;
A clipping processing unit 5 ₃ is prepared to remove the portion that protrudes from the displayable screen frame of the CRT monitor 3, and a frame buffer 6 corresponding to the line segment display position (coordinate position) of the cut out figure information is prepared.
A digital differential analysis (DDA) processing unit ₅₄ is provided which develops the on/off information of the above bit.

The frame buffer 6 is physically a memory that has bits that correspond one-to-one to each pixel on the screen of the CRT monitor 3. For color display, it has multiple bit brains and uses the lookup table 7. to determine the display color.

Returning to FIG. 2, the host computer system 2 uses the host computer 8 as a control center,
As one of the processing functions of online processing, data processed with graphic information is divided into appropriate formats and stored in an auxiliary storage device 9 such as a magnetic disk, and graphic information within the range required by the graphics CRT display device 1 is transferred to the interface. Ace 10, 11, transmission line 1
The received data is transmitted to the graphic CRT display device 1 through the communication line 2, and the received data is stored in the segment buffer ₅₁ in the graphic CRT display device 1.

By the way, when using such a system, after displaying a figure on the screen, there are cases where it is desired to enlarge a part of the area where the figure is displayed. Conventionally, all the graphic information included in the cut out area is displayed, and the size of the graphic elements in the segment structure of the figure information is fixed, so the graphic information included in the cut out area changes depending on the enlargement ratio. uniformly expanded at the same rate. To explain this situation using Fig. 4, figure A is displayed on the tube surface ₃₁ ,
When the area cut out by the dotted line is displayed on the tube surface ₃₁ , the figure A is enlarged according to the area ratio of the tube surface to the cutout area. The same can be said for reduction.

On the other hand, in reality, the importance of graphical information is determined by its properties. When displaying such multiple figure information, when zooming out (when viewing a wide range)
It is sufficient to be able to see only highly important information and understand the whole picture, but when zooming in (when looking at a narrow range), you may want to know detailed information about the cutout area. However, conventionally, all of the graphic information included in the cut out area is displayed in a state in which the groups of shapes included in each graphic information are uniformly enlarged or reduced, so the density of information does not change and the shapes are simply displayed. The above requirements cannot be satisfied because the size of the size is only increased or decreased. In addition, in order to change the size of a figure according to the cutout area, the elements that determine the size of the figure in the segment structure must be changed for each figure each time the cutout area is specified. Therefore, it becomes impossible to increase the speed of graphic display.

D Problems to be Solved by the Invention The present invention has been made based on this background, and provides a graphical display that is easy to see and meets the needs of the viewer when displaying a wide or narrow range. The object of the present invention is to provide a graphic display device that can display images at high speed.

E Means and Effects for Solving Problems In the present invention, graphic information consisting of a group of graphics is stored in a segment buffer as a segment structure, and a size table is also stored in the segment buffer. In this size table, the presence or absence of display of a graphic element and the display size are defined using the graphic type and the index indicating the enlargement rate corresponding to the cutout area as addresses. The graphic type is defined within a graphic element in the segment structure. A control section is provided that includes means for referring to a size table using a graphic type and an index indicating an enlargement rate as an address regarding graphic information to be displayed. For example, in the system shown in FIG. 2, the function of this control section is shared between the host computer and the display processor. Therefore, by referring to the size table, among the graphical elements of the graphical information, those that correspond to "No display" will not be displayed, and those for which the display size is specified will be displayed at that size. Ru.

F. Embodiments Examples of the present invention will be described below with reference to the drawings.

In FIG. 1, I is graphic information consisting of a group of graphics, which is constructed and stored as a segment structure in the segment buffer 5 ₁ (see FIG. 2).
Graphical elements in this segment structure (Fig. 3)
(corresponding to SD) has a figure type defined.
13 is a size table, which is stored in the segment buffer ₅₁ . In this size table 13, the presence or absence of display of the graphic element and the display size are defined using the graphic type in the graphic element included in the graphic information and the index indicating the enlargement rate corresponding to the cutout area as an address. .
To describe the contents of the size table 13 in detail, a to e are graphic types defined by graphic elements;
M ₁ to _{M 5} are indices that indicate the magnification rate according to the cutout area, S ₀ to _{S 5} indicate the display size, and the size group of the horizontal row (row) corresponds to the figure type shown at the left end. The size group of the vertical rows (columns) corresponds to the index indicating the magnification rate shown at the top of the group, and the presence or absence of display of graphic elements and the display size are determined by the intersection of rows and columns. Determined by the content. For example, figure type a
When displaying a graphic element defined with a magnification corresponding to M ₃ , size S ₂ is selected. The size shown here as S ₀ corresponds to zero, and when the size S ₀ is selected, the figure is not displayed. 14 is a control unit, and this control unit 14 is
Determine the graphic information according to the enlargement rate from among the graphic information included in the cutout area, turn on the visibility attribute of the segment structure in the segment buffer ₅₁ related to the graphic information, and refer to the size table. , means for determining whether or not to display a graphic element and the size of the display based on the index and the graphic type included in the determined graphic information. Regarding the reference to the "row" of the size table, the "row" to be referenced is determined by the graphic type in the graphical element of the segment structure, which determines what size the graphical element is displayed. Furthermore, two or more graphic elements may have the same graphic type, and in this case, the same "row" is specified. Although the illustrated size table is a table with 5 rows and 5 columns, in reality, for example, a table with 256 rows and 8 columns is used. Regarding the functions of the control section 14, when applied to the graphic display system shown in FIG. This is performed by dividing the functions between the display processor 4 and the size table reference.

Next, the effect when such an embodiment is applied to the system shown in FIG. 2 will be described.

For example, when the host computer system 2 specifies a certain cutting area corresponding to the enlargement ratio _M1 , the host computer 8 selects graphic information in response to the specification. When a command is input from the host computer 8 to the display processor 4 on the graphics CRT display device 1 side to display graphic information at a magnification ratio corresponding to _M1 , the visible image of the graphic information in the segment buffer ₅₁ is input. Turn on attributes and turn off visible attributes related to graphic information outside the specified area. Furthermore, when the cutout area is determined, the index indicating the enlargement rate (M ₁ in this case) is determined, and the "column" to be referred to in the size table is determined. Then, with reference to the size table 13 corresponding to the graphic information, the presence or absence of a graphic element and the display size of each graphic element are determined based on the graphic type and index _M1 included in the graphic information. In this case, size _S1 is selected for all of the graphic types a to c, and the size of graphic types d and e is zero, which corresponds to no display. Therefore, figure type a~
c is drawn on the frame buffer according to the color information included in the segment structure, and displayed on the monitor by raster scanning the frame buffer. Even if a magnification ratio other than that corresponding to _M1 is specified, graphic information is selected accordingly, and graphic elements are displayed in the same way by referring to the size table.

G. Effects of the Invention As described above, according to the present invention, graphic information is selected by specifying a cutout area, and
By using the size table, the presence or absence of a figure to be displayed and its size are determined according to the magnification ratio, so the density of information and the size of information can be changed depending on the size of the cutout area. . Therefore, when displaying a wide range or a narrow range, the information desired to be viewed can be reliably seen at an appropriate display size, and graphical display that is easy to view and meets the needs of the viewer can be achieved. Moreover, instead of modifying the graphic elements related to the size of the segment structure each time a cutting area is specified, a size table is set up in advance and the size is determined by referring to this table. Because of this, graphics can be displayed at high speed.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an embodiment of the present invention, FIG. 2 is a configuration diagram showing a graphic display system consisting of a graphic CRT display device, which is a graphic display device, and a host computer system, and FIG. 3 is a segment diagram of a graphic display system. FIG. 4 is an explanatory diagram showing a segment structure of graphic information stored in a buffer, and FIG. 4 is an explanatory diagram showing how a graphic is enlarged in a conventional device. 1... Graphic CRT display device, 2... Host computer system, 3... CRT monitor, 4...
Display processor, 5 ₁ ... Segment buffer, 6... Frame buffer, 8... Host computer, 13 ₁ to 13 ₃ ... Size table, 14
...Control unit, I...Graphic information.

Claims (1)

[Claims] 1. Graphic information consisting of a group of graphics is constructed as a segment structure and stored in a segment buffer, and the stored graphic information is designated as an area to be cut out and displayed. In a graphic display device that displays display information of graphic information included in an area, a graphic type is defined in a graphic element in a segment structure of the graphic information, and an index indicating an enlargement rate corresponding to the graphic type and the cutout area. With this as an address, a size table that specifies whether or not to display the graphic element and its display size is stored in the segment buffer, and the size table is referenced to correspond to the shape and cutout area included in the graphic information. 1. A graphic display device comprising a control section including means for determining whether or not each graphic element is to be displayed and the size of the display based on an index indicating an enlargement rate.