JP2885203B2 - Map data display device - 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 data display device for reading and displaying map data according to selection from a recording medium on which map data corresponding to a plurality of scales are recorded.

[0002]

2. Description of the Related Art An electronic map system is a system for reading map data recorded on a CD-ROM as a recording medium and displaying a map. A navigation system is constructed by mounting the electronic map system and displaying the current position on a map. In the current position detection method, for example, position information such as a vehicle speed and a traveling direction is detected via a hardware device mounted on a vehicle, and the information is combined and displayed on a display device. Various methods for obtaining information on the current position using the above hardware device have been studied and implemented.

An electronic map system viewed through hardware such as a navigation system has only a display resolution that depends on hardware. Therefore, the relationship between the range that can be simultaneously viewed on one screen and the object that can be expressed within this range is considerably limited.

[0004] On the other hand, a user requires a map resolution suitable for the purpose of the map. In order to respond to this request, simply changing the scale and displaying it is possible, for example, by recording detailed map data from the beginning on a recording medium and devising the hardware side for display. However, in order to respond to the higher demands of users, it is necessary to respond on the software side. A map viewed through hardware in consideration of the necessity of software has a plurality of sets of map data describing the same area corresponding to the range of a range displayed on one screen. Having a plurality of sets of map data in this way is called map hierarchy. There are a plurality of types of map scales corresponding to this map hierarchy.

[0005] Here, as for the maps at the same hierarchical level, data is taken from an original drawing of the same scale in principle. It is possible to bring the hierarchy further into the map created from the original map of the same scale and display it. This is a function for filling the display resolution of the original image and the display device, which is generally called a “view set”.

This view set includes a plurality of types of view sets, and is set, for example, to display a detailed description of a sequentially displayed map. The map display range at this time is a window provided for each view set.

As described above, in addition to the display depending on the hierarchy (scale level) of the recording medium, the display range is changed and the user displays the desired map data on the screen.

[0008]

By the way, the size of the distance scale displayed in advance in accordance with the map data and the numerical value of the distance corresponding to the size of the distance scale are fixed and used. Has not been fully utilized.

[0009] Here, when displaying by the above-mentioned view set by arbitrarily changing the scale of the display device so as to take advantage of the features of the electronic map display device, the map display screen is a diagram of the map display area shown in FIG. The distance scale size and the numerical value of the distance scale size are shown in the display area of the reduced scale provided in the lower right area of FIG.

If the distance scale size displayed in the scale display area is kept constant and only the numerical value of the distance indicated by the distance scale size is variably displayed, for example, the distance scale shown in FIG. In FIG. 5B in which the numerical value of “2 km” is magnified and displayed seven times, the numerical value of the distance is not represented by a well-divided numerical value. For example, a numerical value of “285 m” is displayed. In this case, since the distance scale size displayed on the map is constantly displayed, the user intuitively determines the distance between two points based on the distance scale size of the reduced scale in multiples of the distance scale size. Easy to catch. However, in many cases, the numerical value of the distance is not a divisible numerical value, and it is difficult for the user to obtain the actual distance from the map, which is complicated and intuitive.

As described above, when the distance scale size of the scale scale is fixed and the numerical value of the distance is changed according to the variable scale of the map, recognition for associating the actual distance with the distance of the map, that is, the map image is displayed. It will be difficult.

Therefore, the present invention has been made in view of such circumstances, and when displaying map data on a screen by performing enlargement / reduction, the distance scale size of the scale display of the map is displayed on the map. It is an object of the present invention to provide a map data display device capable of displaying a numerical value of an optimum distance by changing the range of the map data so as not to disturb.

A map data display device according to the present invention is a map data display device for reading and displaying map data from a recording medium on which map data corresponding to a plurality of scales are recorded. Has an enlargement / reduction display function unit for displaying on the display screen while arbitrarily changing the scale ratio.The enlargement / reduction display function unit includes a plurality of scale ratios in the distance scale display area for displaying the distance scale on the display screen. The above-described problem is solved by displaying a plurality of unit distances set in advance for a section while changing the length of the distance scale according to an arbitrary scale factor to be changed.

Here, the map displayed on the display screen is:
For example, a map area designated as a window for a part of a map at a certain scale level is shown. The above-described problem is solved by displaying the length of the unit distance representing the distance scale displayed in the distance scale display area so as to be within a predetermined range in the distance scale display area while changing the scale. Solve.

Here, the predetermined range is defined as a range not exceeding at least the range of the distance scale display area. The map data display device of the present invention is a map data display device that reads and displays map data from a recording medium on which map data corresponding to a plurality of scales is recorded,
A scale display function unit for selecting a desired region of the read map data and displaying the selected region on the display screen while changing the scale, wherein the scale display function unit includes a distance scale on the display screen. By displaying a distance scale using a unit distance selected from a plurality of unit distances preset for a section of the scale while changing the scale in the distance scale display area for displaying the distance scale display area. The numerical value indicating the unit distance of the distance scale to be displayed in is expressed as a limited number and a simple integer value, and the symbol length, which is the display length of the distance scale, falls within the variable range set according to the above scale factor Display as follows.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a map data display device according to the present invention will be described with reference to the drawings.

The map data display device according to the present invention will be described with reference to the schematic functional block configuration shown in FIG. Here, the map data is an optical disk, for example, a CD, which can have a large amount of digital data.
-Written in the ROM 10.

The map data display device includes a data reading unit 11 serving as a data reading unit for reading information recorded on a recording medium, a process based on information from the data reading unit 11, and a map reading unit. A data processing unit 12 which is an enlargement / reduction display function unit for displaying a desired area of data at an arbitrary size on a display screen; and a graphic control unit 13 which is a display control means for controlling display data from the data processing unit 12 And a display device 14 as display means for displaying an output signal from the graphic control unit 13.

The operation based on this circuit configuration is as described below. Digital data recorded on the CD-ROM 11 shown in FIG. 1 is supplied to a data processing unit 12 via a data reading unit 11. The data reading section 11 is generally constituted by an optical pickup 11a and a signal processing circuit 11b.

The optical pickup 11a has a C
It is driven according to a control signal from a PU (Central Processing Unit: CPU) 12a and moves to a target position.
The target position is irradiated with laser light, the return light reflected by the CD-ROM 10 is converted into an electric signal, and the signal processing circuit 11b
To supply. The information thus read is sent from the signal processing circuit 11b to the CPU 12a in the data processing unit 12.

The data processing unit 12 includes a CPU 12a for controlling a map data display device, a RAM 12b for temporarily storing read information, a data processing procedure for creating image data, and a table for displaying a scale display. And the like are written in the ROM 12c which is a storage means.

The CPU 12a stores the input information in the RAM 1
2b for writing. Also, R
AM 12b is read again in response to a read signal from CPU 12a. The ROM 12c has, for example, a table for storing a control processing program for a display operation of the map data display device and data to be displayed in a distance scale display area. The CPU 12a supplies a control signal to the ROM 12c. The ROM 12c operates the device according to the supplied control signal and the written processing program procedure. Further, as data of a table preset in the ROM 12c, data to be displayed in the distance scale display area is created in advance under the control of the CPU 12a as shown in a flowchart of FIG.

By operating on the basis of the information stored in the ROM 12c in this manner, a map display corresponding to an arbitrary enlargement or reduction and a simple enlargement for display in the distance scale display area on the map are performed. Alternatively, distance scale display can be performed at high speed by taking measures for reduction.

A simple integer value is used for the numerical value displayed in the distance scale display area. This simple integer value is, in principle, a preset integer such as 1, 2, 4, 5, etc., and its integral multiple of 10 (where N is an integer, 10 N times).
It is preferable that Alternatively, as the simple integer, a divisible number, for example, 25 or 250, which is a product of an integer power of 10 and a reciprocal of a preset integer can be used. When the above simple integer is used as the scale value, it is easy to measure the distance between the points displayed on the map based on the reduced scale and the distance scale. Note that seven types of scale values can be set as one set together with the length of the corresponding scale bar. The setting of this scale value is 70 km, 15 km, 4 km, not set,
Each of 2 km, 1 km, and 250 m is an integer that can be easily multiplied, that is, an integer value that is easily divisible.
For the scale bar length 20a and the scale value 20b used for the scale display that is set in advance in the distance scale display area 20 shown in FIG. 2, display data is created with reference to a table in the ROM 12c.

The program and CPU of the ROM 12c
The map data read from the CD-ROM 10 under the control of 12a and subjected to data processing necessary for displaying the map is sent to the graphic control unit 13. The graphic controller 13 includes a GDC (graphic display controller: hereinafter abbreviated as GDC) 13a and a V-RAM (video RAM: abbreviated as V-RAM) 13b.

The map data supplied to the graphic controller 13 is stored in the V-RAM 13 under the control of the GDC 13a.
b and temporarily stores the map data. By storing the map data in the V-RAM 13b in this manner, the display on the display device 14 can be performed more easily.

Information such as the read image data is displayed on a two-dimensional display screen of the display device 14 in response to an operation of an operation unit (not shown) (see FIG. 2).

By storing in the table the data relating to the preset scale scale configured in this manner, it is possible to replace the recording medium with another scale scale,
Even when using a storage medium in which other map areas are recorded, an area whose size is specified is converted into map data within, for example, an allowable variable range of a window, and a scale value and a scale that can be easily divided into areas that do not interfere with the display of a reduced scale. -A bar can be displayed.

Here, the relationship between the scale ratio of the map to be actually displayed and a plurality of unit distances set in advance for displaying the distance scale and the display of the scale scale and the distance scale of the map to be actually displayed (symbol) (A) of FIG.
This will be described with reference to FIGS.

The relationship between the scale of the map actually displayed in FIG. 3A and the unit distance of the distance scale is represented by a log-logarithmic graph. For example, in FIG. 3A, the range is set so that sections in which the scale is substantially constant are the same. In other words, the unit distance of the distance scale is set so that only a plurality of limited numbers are displayed.

The symbols (lengths) displayed in the distance scale display area corresponding to FIG. 3A are, for example, within a range R of ± 0.6 cm with reference to 1 cm shown in FIG. 3B. You have set. Here, if the range of the scale shown by the broken line A in FIG. 3A is treated as a constant distance, areas B1 and B2 exceeding the variable range shown in FIG. 3B are generated.

Therefore, in order to display the symbols so as not to exceed the set range while varying the length of the symbols, first,
The distance scale display area is defined by a size that does not disturb the map display. The set number of scale ratios that reach the standard 1 cm within the arbitrarily variable scale range is determined by satisfying the condition that the length of the variably displayed symbols does not exceed the specified range.

By setting the length of the scale bar as described above, the length of the scale bar can be represented by a length of about 1 cm in the above-described setting, for example, and the scale intuitive for the user. Helping to understand. In addition, since this scale value is represented by the above-described simple integer value, the actual distance can be easily calculated by mental calculation.

The procedure for setting and displaying the scale scale displayed on the map will be described with reference to the flowchart shown in FIG. FIG. 1 is referred to as needed. The display of the scale level is a part of the routine for displaying the map data. Activate the map data display device and press C
The D-ROM 10 is set.

In step S10, a scale bar length (distance scale size as a display length) and a scale value, which are display parameters of the reduced scale display, stored in the ROM 12c shown in FIG. 1 for simplifying the routine. (A numerical value indicating a unit distance) is stored in a table. The operation of storing the data in the ROM 12c is performed in advance at the time of manufacturing. Therefore, the RO
When using the values of the table stored in M12c, the operation for creating the table is jumped and the process proceeds to step S11.

In step S11, the size of the scale level to be displayed is specified according to the operation of the map data display device. The user can arbitrarily specify the size of this scale level. After this scale level designation, the process proceeds to step S12.

In step S12, the display data of the length of the scale and the numbers stored in the table is stored in step S1.
The map is converted to the size on the display screen of the map whose size is specified in 1. This conversion process is performed by the CPU 12a shown in FIG. The result of this conversion processing is stored in the RAM 12b. After this conversion process, the process proceeds to step S13.

In step S13, it is determined whether the data converted in step S12 is suitable for the variable range of the scale bar. Here, the variable range of the length of the unit distance in the map display is defined. If it is determined that the data converted to the variable range of the scale bar is inappropriate, the process returns to step S12 to convert the scale value in the next table to the size on the display screen whose size is specified. According to this routine, the scale scale conversion processing sequentially converts the scale value in the table into the size on the display screen corresponding to the scale value in the table.

If it is determined in step S13 that the data in the table falls within the variable range of the scale bar on the display screen and is appropriate, the process proceeds to step S14. As described above, by causing the apparatus to determine whether or not the scale is a scale that can be displayed on the map of the designated size, it is possible to display only the scale that can be displayed without the user's determination.

In step S14, the data of the reduced scale, that is, the scale bar and the scale value are superimposed and displayed on the screen displaying the map data read from the CD-ROM 10.

At this time, the scale value displayed is a numerical value that is easily divisible. For example, FIG.
When the scale value “2 km” of the reduced scale shown in FIG. 5A is enlarged and displayed 7 times, “285” is displayed in FIG.
"m" and a scale value that is difficult to perform a multiple operation is displayed as it is. However, the map data display device of the present invention can display the scale value “250 m” within the variable range of the scale bar from the table while specifying the size as shown in FIG. doing.

The recording media are all at the same scale level,
For example, there is a recording medium having a nationwide scale and a recording medium having map data only in each region, which are not represented by so-called hierarchies. If this map data display device is stored in the ROM 12c so as to perform distance scale display from numerical values set in advance according to the layers included in these recording media, the map data display device can also be used for recording media formed in another layer. The display of distance information (scale value, scale bar) can be displayed in the distance scale display area in the same manner as described above. In addition, as shown in FIG.
In addition to displaying a certain range including 1000, 1/2000,..., 1/10000 and the like as a unit distance, for example, a section of a reduced scale level indicating a break of the hierarchy,
It is also possible to display the scale value with a constant value and to change the display length of the scale bar in accordance with enlargement or reduction.

As described above, the map data display device designates a map area desired by the user, selects a scale value corresponding to a variable range permitted in the scale-variable display of the map from the table, and displays the map value on the map. , The multiple operation can be easily performed by mental arithmetic. For this reason,
The map data display device facilitates eye measurement based on the display of the accurate distance value and the distance scale size, so that the map size can be recognized intuitively. As a result, when the map data display device is mounted on a vehicle and used in a situation where other processes are being performed at the same time, such as while actually driving a moving object such as an automobile, the recognition of the map size is effective without a sense of incongruity. Can be done.

Further, by storing the data relating to the preset scale scale in the table as described above, it is possible to replace the recording medium with another scale scale or use a storage medium in which another map area is recorded. Even though the specified area is converted into map data within, for example, an allowable variable range of the window, it is possible to display a well-divided scale value and a scale bar in an area that does not interfere with the display of the reduced scale.

When the map data display device calls and displays a map area desired by the user from a plurality of map data, if the scale levels of the plurality of map data are different, the plurality of map data are displayed. The scale is adjusted in common, so that it looks like a single map in appearance.

In the operation procedure of the map data display device,
By causing the device to determine whether or not the scale is a scale that can be displayed on a map of a designated size, it is possible to display only the scale that can be displayed without the user's determination.

[0047]

As is apparent from the above description, according to the map data display device of the present invention, a map for reading and displaying map data from a recording medium on which map data corresponding to a plurality of scales is recorded. In the data display device, there is provided an enlargement / reduction display function unit for selecting a desired area of the read map data and displaying the selected area on a display screen while arbitrarily changing the scale. In the distance scale display area for displaying the distance scale on the display screen, the display length using a unit distance selected from a plurality of unit distances preset for a section of the scale while arbitrarily changing the scale. By displaying the distance scale where the distance is changed, it is possible to intuitively recognize the map size based on the display of the accurate distance value and the unit distance of the distance scale. It was actually in parallel at the same time such while driving the movable body such as an automobile when used in situations that do other work or the like, it is possible that the recognition of the map size effectively performed without discomfort.

The length of the unit distance representing the distance scale displayed in the distance scale display area of the map data display device is displayed so as to be within a predetermined range in the distance scale display area while changing the scale. By doing so, it is possible to display only the scale scale that can be displayed without the user determining whether the scale scale can be displayed on the map of the designated size.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic block configuration in a map data display device according to the present invention.

FIG. 2 is a diagram showing an example of a display screen on which a scale display is displayed in a map whose size is designated;

FIG. 3 shows a relationship between a plurality of unit distances set in advance to display a scale of a map to be actually displayed and a distance scale, and a length of display (symbol) of a scale and a distance scale of a map to be actually displayed. FIG. 3 is a schematic diagram showing a relationship between the above and FIG.

FIG. 4 is a flowchart illustrating a procedure for displaying distance information to be displayed in a distance scale display area while maintaining the relationship shown in FIG. 3 using the schematic block configuration shown in FIG. 1;

FIG. 5 is a schematic diagram showing a display of a numerical value of a distance that is not easily divided when a distance scale size of a conventional scale display is displayed at a fixed length.

[Explanation of symbols]

Reference Signs List 10 CD-ROM, 11 data reading unit, 12 data processing unit, 13 graphic control unit, 14 display device

Continuation of the front page (56) References JP-A-63-4400 (JP, A) JP-A-4-335390 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G09B 29 / 10 G01C 21/00 G08G 1/0969

Claims (2)

(57) [Claims] 1. A map data display device for reading and displaying map data from a recording medium on which map data corresponding to a plurality of scales is recorded, wherein a scale of a desired area of the read map data is changed arbitrarily. br /> has a scaling display function unit to be displayed on the display screen while reduction, the scaling display function unit, a distance scale display area for displaying the distance scale on the display screen, for a plurality of sections to scale for preset plurality of unit distance it was, is changed
A map data display device for displaying while changing the length of a distance scale according to an arbitrary scale factor . 2. A display length of the distance scale displayed in the distance scale display area is displayed so as to be within a predetermined range in the distance scale display area while changing the scale. The map data display device according to claim 1.