JPH0527879B2 - - Google Patents

Description

[Detailed description of the invention]

(Technical Field) The present invention relates to a graphic display device using a graphic CRT display device, and more particularly to a display information processing method. (Prior art and problems) Graphic CRT display devices have higher precision (resolution) of information that users can manage than conventional character-type display devices, and are more complex. It enables precise display, and its uses have expanded as the functions required of various systems have become more sophisticated, and it is still used in a wide variety of applications, including image processing, CAD/CAM, and animation. Among the graphic display devices using this graphic CRT display device, the device mainly targeted by the present invention is
Like CAD/CAM, line figures are displayed, but CAD/CAM differs greatly from CAD/CAM.
In CAM, the display target is a single closed figure, whereas in the present invention, the display target is applied to the display of figures that are widely distributed on a plane. For example, for graphical information distributed discretely on topography, it can be applied to extract graphical information in a designated area from the information covering the entire area and display the graphical information on a CRT display device based on the information. It is something to do. An example of the configuration of a graphic display device using a graphic CRT display device is shown in FIG. Host computer system A includes host computer 1 and storage device 2.
and an interface 3-1, and for graphical display, the desired display information is retrieved from the storage device 2 under the control of the host computer 1 and sent to the graphic CRT display device B via the interface 3-1.
give to CRT display device B includes an interface 3-2, a display processor 4, a video memory 5, a monitor 6, and a picture memory 7.
The processor 4 receives display information from the host computer system A through the interface 3-2.
The image is displayed as a graphic on the monitor 6 under the control of. In such a graphic display device, when the host computer 1 receives a display request for a partial area of display information, the conventional display processing outline is as follows. (i) The host computer 1 uses the area information instructed to be displayed to calculate the coordinate values of the area of the display information to be transmitted to the graphic CRT display device B. (ii) The host computer 1 searches for display information contained within the above area. (iii) After the host computer 1 performs processing such as coordinate transformation and information editing on the searched display information,
Transfer to graphic CRT display device B. (iv) The display processor 4 constructs the received display information into a database within the graphic CRT display device and stores it in the picture memory 7. (v) The display processor 4 processes information stored in the picture memory 7 and performs control to develop it on the video memory 5. This deployment uses special internal hardware. (vi) The bit image developed on the video memory 5 is displayed as a figure on the monitor 6. These conventional processing methods have a problem in that the processing time from the display request to the display completion is long.
There are two reasons for this: (1) This is mainly due to the processing capacity of the display processor, but it takes time to transfer information between the host computer system A and the graphic CRT display device B. (2) The search for display information performed by the host computer 1 takes time because it searches for information located within an arbitrary small area from a huge amount of display information distributed over a surface area. Also,
Conventional processing methods have had the problem that the amount of information handled by the host computer system is enormous.
The causes of this are as follows. (3) In addition to code information indicating the content of display information, coordinate information indicating the display position within the entire display area is required. In the above-mentioned problem, display information processing of a figure whose display targets are dispersed will be specifically described below. Each element of display information within the area that spreads over the area has coordinate information for indicating the position within the area. Each coordinate is set as a distance from the origin when one point within the area is the origin (hereinafter referred to as absolute coordinates). Therefore, the data structure of each display information is
As shown in Table 1 below, the absolute coordinates X, Y and information type. color. DATA that gives meaning to attributes etc.
The display information as a whole is a collection of these.

[Table] Searching for display information within a certain section (certain area) from a display information group having such a data structure is as follows. The total number of display information is N, and each display information
Di (i=1, 2,...N) is defined by the following equation. Di={(Xi, Yi), DATAi} Also, let the coordinates of the upper right and lower left of the rectangular area specified for display be (X _RU , X _RU ) and (X _LD , Y _LD ), respectively. At this time, it is determined whether or not X _LD ≦Xi≦X _RU Y _LD ≦Yi≦Y _RU is satisfied for each display information Di, and when both expressions are satisfied, the display information Di falls within the rectangle. Suppose there is.
This process is performed on all display information, and as a result, the display information that falls within the designated rectangle is determined. Note that when the display information Di is vector information, the search processing contents are different because the absolute coordinates are paired, but the processing method is substantially the same. As is clear from the above explanation, the conventional data structure and its processing method have the following specific drawbacks. Note that (2-1) and (2-2) are the same as the above 2
(3-1) corresponds to the above-mentioned three terms. (2-1) Since it is necessary to determine whether each piece of display information falls within a designated area, the processing time becomes enormous in proportion to the amount of display information. Particularly when the actual specified display range is a part of the entire area, the amount of determination processing is large despite the small amount of required display information, resulting in very poor calculation efficiency. (2-2) Since all display information is to be processed, it takes an enormous amount of time to load that information from the auxiliary storage device onto the main memory. In other words, the total amount of display information can be several tens of megabytes or more, and must be loaded from the auxiliary storage device onto the main memory and processed by the host computer, which requires the transfer of information from the auxiliary storage device to the main memory. Requires. (3-1) The coordinate value to indicate the position of display information is
The amount of information that requires 4 bytes each for the direction and the Y direction requires a total of 8 bytes as coordinate information, and the total amount of information for this becomes enormous. For example, in a two-dimensional display, if the actual distance of 1m is the coordinate unit and the total display area is 100km square, then
There may be 100×10 ² ×100×10 ³ =10 ¹⁹ coordinate points. Since this value is larger than the number 65.536 that can be expressed in 2 bytes, the coordinates are expressed in 4 bytes. Note that the number of coordinate points differs in coordinate units and in the entire display area, but generally a 2-byte coordinate representation cannot correspond to various cases.
In addition, the information units handled by computers are usually even-numbered bytes such as 2 bytes, 4 bytes, and 6 bytes.In the above case, it may be possible to handle 3 bytes, but depending on the specifications of the computer, it may be handled in units of 4 bytes. In many cases, it is necessary to handle the (Object of the Invention) The present invention has been made in view of the above-mentioned circumstances, and it reduces the amount of coordinate information for indicating the position of display information, improves the efficiency of use of the storage device, and improves the process from display request to display completion. An object of the present invention is to provide a graphic display device that can shorten processing time. In a specific example of the above-mentioned drawback, directly (3-
Solving 1), the ripple effect is (2-1),
(2.2) is solved. (Summary of the Invention) The present invention divides a display information group into a plurality of subsets, stores and manages them, adds representative coordinate information to each subset that indicates the display position within the entire display area, and stores information within each subset. The display information group is characterized in that relative coordinate information with respect to representative coordinate information is given as figure position information, and position information of each display information is obtained from the representative coordinate information and relative coordinate information. (Example) Examples of the present invention will be described in detail below with reference to the drawings. First, on the condition that display information can be managed in any form, display information is divided into a plurality of subsets and stored and managed. For example, as shown in Figure 2A, the entire display area where display information is distributed (the shaded area) is divided into multiple rectangular areas of the same size, and each rectangular area is parallel to the X and Y axes. Each line segment and each piece of display information belong to a single rectangle. However, display information located on the boundary of a rectangle is made to belong to one of the adjacent rectangles. As another example, as shown in FIG. 2B, when the entire display area is divided into a plurality of regional subsets, each subset is stored and managed as a closed region. At this time, each subset area is not limited to being set as a rectangular area (broken line block in FIG. 2B) that covers the area, but may also be set as a subset along the subset area of the display information. Note that the display information of the portion where the subset regions overlap each other includes portions belonging to each. As illustrated in Figure 2 AA and B, by dividing individual display information into multiple subsets and storing and managing them, each display information belongs to one subset, and the subset can be specified. makes all display information it contains searchable. Next, representative coordinate information indicating where it is located within the entire display area is added to each subset. This representative coordinate information is location information added to the conventional display information.
Like Xi and Yi, it is a 4-byte number. This representative coordinate information is absolute coordinates (AXi, AYi) based on the origin coordinates set in the entire display area, and absolute coordinates (AXi, AYi) are assigned to each subset Ki (i=1, 2,...n), respectively. Save and manage one additional item. Next, the display information group belonging to each subset Ki is stored and managed by giving relative coordinates as relative coordinate information from the representative coordinates (AXi, AYi) of the subset Ki to which it belongs as position information indicating the figure display position. do. This relative coordinate (X, Y) is given as a 2-byte numerical value. These absolute coordinates (AXi, AYi) and relative coordinates (X, Y) have a relationship as shown in FIGS. 3A and 3B. That is, as shown in the absolute coordinates in FIG. 3A, the subsets K ₁ , K ₂ , and K ₃ have 4-byte representative coordinates (AX ₁ , AY ₁ ), respectively, at appropriate positions within the set.
Given (AX ₂ , AY ₂ ), (A ₃ , AX ₃ ), each subset
Give 2-byte relative coordinates (X, Y) for each representative coordinate in K ₁ , K ₂ , and K ₃ . In Fig _{. 3B ,} relative values _{( X 1} ,
Y′ ₁ ), (X ₂ , Y ₂ ) are given. Using these 4-byte absolute coordinates (AXi, AYi) and 2-byte relative coordinates (X, Y), in order to specify the position coordinates of the display information group within the entire display area, the size of each subset Ki is the representative coordinate. The condition is that it can be expressed in a 2-byte coordinate space from do not have. From the above, the display information group Dj in the subset Ki
is expressed as Dj={(Xj, Yj), DATAj), where Xj, Yj are the relative coordinate values of the j-th display information Dj among the total L display information groups, and DATAj is the j-th display information Dj. This becomes the display entity information such as the display type, color, and attribute of Dj, and the set Si of the display information group Dj (j=1, 2, . . . , L) subset Ki is as shown in Table 2 below.

【table】 : : :

Claims (1)

[Claims] 1. Display information of a figure that spreads over a surface is stored in a storage device as digital information, a processing device extracts display information of a partial figure that is requested to be displayed from the above storage device, and displays the extracted display information as a figure. A graphics display device for displaying on a graphic CRT display device, wherein the storage device stores display information divided into a plurality of subsets, and adds representative coordinate information to each subset indicating the display position within the entire display area. The display information group in each subset is given its position information as relative coordinate information with respect to the representative coordinate information and stored, and the processing device converts the position information of each display information in the subset into the representative coordinates of the subset. A graphic display device characterized in that information is obtained from information and relative coordinate information of the displayed information.