JP2806270B2 - Map display control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a map information processing system for vector data (a map information processing system for expressing map information indicating roads, buildings, map symbols and characters using vector data). The present invention relates to a map display control method for controlling display of a map.

[0002]

2. Description of the Related Art Generally, a map information processing system reads an existing map with an image scanner and processes the map as raster data, and maps elements constituting the map to coordinate values (forming elements forming the map). And the map information processing system which manages the coordinates of the line segment and the vector information and expresses the element as vector data.

[0003] The former map information processing system (map information processing system for raster data) has a main purpose of displaying a map only, and displays a map on a graphic display device mounted on a vehicle to display a map of a driver. An application example is a navigation system that provides road guidance. The maps targeted by this map information processing system are mainly road information, and are often relatively simple.

On the other hand, the latter map information processing system (map information processing system for vector data) has a main purpose of operating the map more than displaying the map, and has a water supply facility, a power facility, and a gas facility. An application example is an equipment design system for underground buried objects. Many of the maps targeted by this map information processing system are more detailed than those targeted by the former map information processing system.

As described above, the present invention is applied to the latter map information processing system.

In these map information processing systems, maps are handled at various scales. That is, even when a map of the same area is displayed, the display is performed at a scale suitable for the purpose of use. In particular, in a map information processing system targeting vector data, an optimal scale is required at each stage of a map information operation process in facility design or the like. It is necessary to change the scale of the target map itself.

In the map display control method in the map information processing system, one of the following two methods is often performed for controlling the change of the scale of the map.

[0008] A method of storing map information on a map of the same area in a separate file for each required scale, and extracting and displaying map information on a map of a designated scale each time.

[0009] Only map information for a specific scale is stored in a file as map information relating to a map of the same area,
A method for displaying a map that fits a specified scale by enlarging / reducing the map at that scale

[0010] Of these two systems, the system is generally employed, and the present invention is directed to a map display control system in which the system is performed.

Conventionally, in this type of map display control method, when a map is enlarged / reduced so as to conform to a display scale (scale of a map to be displayed), the map is simply enlarged / reduced as a graphic. However, the display contents have not been changed (e.g., selection of which map information should be displayed) due to the enlargement / reduction. On the other hand, in general, there is a demand to display more map information when the map is enlarged, and there is a demand to omit extra map information when the map is reduced.

[0012]

In the above-described conventional map display control method, since the map is simply enlarged / reduced as a graphic and the display content is not changed with the enlargement / reduction, it is stored in a file. When the scale of the displayed map is changed to the display scale, there is a problem that it is not always possible to obtain a map having contents that match the scale after the change. Therefore, in order to cope with such a change in the scale, it is necessary for the operator to “change the content of selection between map information to be displayed and map information not to be displayed”. There is a drawback that this leads to a decrease in

In view of the foregoing, an object of the present invention is to provide a map information processing system for vector data, in a map display control system for controlling a change in scale of a map to be displayed, in accordance with a display scale. It is an object of the present invention to provide a map display control method capable of displaying a map having appropriate contents (a map in which map information to be displayed and map information not to be displayed are appropriately selected).

In the map information processing system for raster data, a measure for dealing with a similar problem (a measure for displaying a map having appropriate contents according to the display scale).
For example, a technique according to Japanese Patent Application Laid-Open No. 58-122593 (graphic display device) has been proposed. This technology is
"Among the map information stored in the first storage means, the map information is stored in a predetermined priority order for each of the scales from the information section predetermined according to the scale set by the scale setting means. A display control unit having two storage means;
And display means for displaying the map information stored in the storage means.
(Refer to page 7, left column, lines 7-13), the correspondence between the information section (set of dots) in the graphic memory (first storage means) and the set of dots in the refresh memory (second storage means) is represented by a scale factor. And it is assumed that raster data is targeted. Therefore, this technology has a different configuration from the present invention, which is applied to a map information processing system for vector data.

[0015]

A map display control method according to the present invention is a map information processing system for vector data. In a map display control method for controlling a change in the scale of a map to be displayed, the map display control method comprises the steps of: A scale management table for setting display control information indicating whether the information type item is displayed at each scale, a map information file storage means for storing map information in a map information file for each map information type item ,
Display control information setting means for setting display control information in the scale management table; and map information stored in the map information file based on the scale management table in which display control information is set by the display control information setting means. Map information type item to be displayed at the specified display scale from
A corresponding map information extracting means for extracting only the eye map information,
And an extracted map information display means for displaying the map information extracted by the corresponding map information extraction means.

[0016]

According to the map display control method of the present invention, the map information file storage means stores the map information in the map information file, and the display control information setting means stores the map information type in the scale management table.
Display control information indicating whether or not to display another item at each scale is set, and the corresponding map information extracting means is stored in the map information file based on the scale management table in which the display control information is set by the display control information setting means. Only the map information corresponding to the display scale is extracted from the existing map information, and the extracted map information display means displays the map information extracted by the corresponding map information extraction means.

[0017]

Next, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the map display control system according to the present invention.

The map display control method of the present embodiment includes a map information file storage means 1, a display control information setting means 2, a corresponding map information extraction means 3, an extracted map information display means 4,
It includes a map information file 5 set on a magnetic disk or the like, a scale management table 6, and a graphic display device 7 having a display memory 71 and a display 72 (see FIG. 5).

FIG. 2 is a diagram for explaining the operation of the map information file storage means 1. Each piece of map information stored in the map information file 5 by the map information file storage means 1 is represented by a coordinate value (x coordinate and y coordinate of the start point and end point of the line segment).
), And management information indicating a scale, a map information type, a display color, a line type, and the like.

FIG. 3 is a diagram showing the configuration of the scale management table 6. The scale management table 6 is a table that has a dimension of a scale item and a dimension of a map information type item, and holds display control information specified by both items. Note that “1” in the display control information indicates “display target”, and “0” indicates “not display target”.

FIG. 4 is a flowchart showing the processing of the corresponding map information extracting means 3. This processing includes a scale management table reading step 401 and a map information reading step 402.
And a display object determination step 403 and a map information display memory storage step 404.

FIG. 5 is a diagram for explaining the operation of the extracted map information display means 4.

Next, the operation of the map display control system according to the present embodiment configured as described above will be described.

As shown in FIG. 2, the map information file storage means 1 reads each piece of map information (vectorized map information and management information) constituting the map to be displayed, and writes the map information into the map information file 5. .

The map information file storage means 1 performs a process of writing all the map information relating to the map to be displayed into the map information file 5 described above.

The display control information setting means 2 sets each display control information specified by the scale item and the map information type item in the scale management table 6 (see FIG. 3). That is, when map information of a map information type (information indicating roads such as national roads and map symbols) on a map of a certain scale (scales such as 1/500 and 1/1250) is to be displayed, "1" is set to the display control information specified by the scale item related to the scale and the map information type item related to the map information type. Also, if map information of a map information type on a map of a certain scale should be excluded from display,
“0” is set to the display control information specified by the scale item related to the scale and the map information type item related to the map information type. The value of each display control information is provided by the operator from an input device such as a keyboard.

The corresponding map information extracting means 3 performs the following processing (see FIG. 4).

Before reading map information from the map information file 5, first, the scale management table 6 is read (step 401).

Next, each map information is sequentially read from the map information file 5 (step 402).

Based on the reference to the scale management table 6 read in step 401, the map information read in step 402 is a map to be displayed at the display scale (display scale in the current map display given by the operator in advance). Information (hereinafter, "map information corresponding to the display scale"
Is determined (step 40).
3).

In step 403, "The map information read in step 402 is the map information corresponding to the display scale (the scale item related to the display scale and the map information type item related to the map information type of the map information in the scale management table 6). The display control information specified by "1" is "1"). "
(When the map information is determined to be a display target), the map information is stored in the display memory 71 in the graphic display device 7 (step 404), and the next map information (in the map information file 5) is stored. Control is returned to step 402 in order to read the next record of

On the other hand, in step 403, "step 402
Is determined to be not the map information corresponding to the display scale (the display control information is “0”) ”(when the map information is determined to be out of the display target), Control returns to step 402 to read map information.

The process shown in FIG. 4 ends when the process for all the map information (records) in the map information file 5 is completed.

As shown in FIG. 5, the extracted map information display means 4 is provided with a display memory 71 by the corresponding map information extraction means 3.
Is displayed on the display 72 in the graphic display device 7. As a result, display of a map having appropriate contents according to the display scale is realized.

[0036]

As described above, according to the present invention, display control information is set in a map display control system for controlling a change in scale of a map to be displayed in a map information processing system for vector data. By using the scale management table or the like, it is possible to automatically display a map having contents suitable for the display scale without requiring the operator to perform display control every time the map is displayed. That is, unlike the conventional case, the "change in the selection of the map information to be displayed and the map information not to be displayed when the scale is changed" does not depend on the operator. It becomes possible.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment according to a map display control method of the present invention.

FIG. 2 is a diagram for explaining an operation of a map information file storage unit in FIG. 1;

FIG. 3 is a diagram showing a configuration of a reduced scale management table in FIG. 1;

FIG. 4 is a flowchart showing a process of a corresponding map information extracting means in FIG. 1;

FIG. 5 is a diagram for explaining the operation of the extracted map information display means in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Map information file storage means 2 Display control information setting means 3 Applicable map information extraction means 4 Extracted map information display means 5 Map information file 6 Scale management table 7 Graphic display device 71 Display memory 72 Display

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G06T 1/00 G09G 5/00 G09B 29/00

Claims (3)

(57) [Claims] In a map information processing system for vector data, a map display control method for controlling a change in scale of a map to be displayed indicates whether each map information type item is displayed at each scale. A scale management table that sets display control information, a map information file storage unit that stores map information in a map information file for each map information type item, and a display control information setting unit that sets display control information in the scale management table. Based on the scale management table in which the display control information is set by the display control information setting means, display is performed at a designated display scale from the map information stored in the map information file. A corresponding map information extracting means for extracting only the map information of the map information type item, and the map information extracted by the corresponding map information extracting means are displayed. A map display control method comprising: extracted map information display means. 2. It has a dimension of a scale item and a dimension of a map information type item, holds display control information specified by the scale item and the map information type item in a table format, and indicates “1” indicating “display target”. 2. The map display control method according to claim 1, further comprising a scale management table indicating display control information by "0" indicating "not displayed". 3. A graphic display device comprising a display memory and a display, wherein the corresponding map information extracting means sets map information corresponding to a display scale in the display memory, and the extracted map information display means sets the map information in the display memory. 3. The map display control method according to claim 1, wherein the displayed map information is displayed on the display.