JPH06347279A - Onboard map display device - Google Patents

Abstract

PURPOSE:To display a road map easy to see with the adjusting of the number of characters to be displayed by dividing a display screen into a plurality of areas to set characters to be displayed for each divided area. CONSTITUTION:A road map data is read out of a display control means 102 from a memory means 100. A character data retrieving means 103 retrieves a character data corresponding to a display range of a display device 101 from the road map data. A screen division means 104 divides a display screen into a plurality of areas according to a display mode. A display character setting means 105 sets characters to be displayed from among character data retrieved for each divided area by the character data retrieving means 103. Then, display characters for each divided area is displayed superimposed on the road map shown on the display device 101. In addition, a screen division means 104A is provided to divide the display screen into the optimum number of parts according to a display mode during the stoppage and the display mode during the running. Thus, the number of division parts is increased during the stoppage to display more information.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle-mounted map display device for displaying a current position of a vehicle on a road map and guiding an occupant to a destination.

[0002]

2. Description of the Related Art A vehicle-mounted map display device is known in which, in accordance with a display priority set by an occupant, map information is displayed on a display device in order from a map information having a higher order until a predetermined display density is reached (for example, Japanese Patent Laid-Open No. Hei 10-1999) 1-213516 gazette). In this on-vehicle map display device, when the occupant sets the display priority of information items, the map information stored in the storage device is read out in order from the item with the highest order until the display density reaches a predetermined display density. Is displayed on the display device.

[0003]

However, in the above-described conventional vehicle-mounted map display device, since the display density of the entire display screen is calculated and the display processing is performed, the distribution of the display density varies depending on the screen. However, if characters such as road names are concentrated and displayed on a portion of the road where the display density is high, there is a problem that it becomes difficult to see.

An object of the present invention is to provide a vehicle-mounted map display device in which a display screen is divided into a plurality of areas and the number of characters displayed in each divided area is adjusted to make the road map easy to see.

[0005]

The present invention will be described with reference to FIG. 1 which is a claim correspondence diagram. The present invention is based on a storage means 100 for storing road map data and a storage means 1 for storing the road map data.
Display 1 based on road map data read from 00
It is applied to a vehicle-mounted map display device including a display control unit 102 for displaying a road map on 01. Then, from the road map data read by the display control means 102, character data search means 103 for searching character data corresponding to the road map in the display range of the display 101, and a plurality of display screens depending on the display mode. Screen dividing means 1 for dividing into areas
04 and display character setting means 105 for setting a character to be displayed from the character data searched by the character data searching means 103 for each divided area by the screen dividing means 104. The above-mentioned object is achieved by displaying the display character for each divided area set by the display character setting means 105 so as to be superimposed on the road map displayed on the display 101. Also,
The display mode of the vehicle-mounted map display device according to claim 2 includes at least a display mode in which the vehicle is stopped and a display in which the vehicle is running, and is optimal depending on the display mode in the stopped state and the display mode in the traveling by the screen dividing unit 104A. The display screen is divided into the number of divisions.

[0006]

Operation: Display characters are set for each of the areas divided according to the display mode, and the characters are superimposed and displayed on the road map. As a result, the characters can be displayed uniformly on the entire screen.

[0007]

FIG. 2 is a block diagram showing the structure of an embodiment. The current position detection device 1 detects the current position of the vehicle by self-contained navigation or GPS. The self-contained navigation is a method of calculating the position of the vehicle based on the traveling distance of the vehicle detected by the vehicle speed sensor, the traveling direction of the vehicle detected by the angular velocity sensor, and the road map data. Also, G
PS is a position detection system using satellites. The external storage device 2 is a storage device such as a CD-ROM for storing road map data, and the input device 3 is an input device for selecting a destination setting and various display modes. The ROM 4 is a memory that stores various control programs executed by the control circuit 5, and the RAM 6 is a memory that temporarily stores display data and the like. Further, the storage device 8 is a memory such as an EEPROM or a backup RAM that stores the contents of change processed by the control circuit 5. The display device 8 is a display device such as a CRT or a liquid crystal that displays a road map. The control circuit 5 is composed of a microcomputer and its peripheral parts, sets a display position of characters such as a road name, and displays it on the display device 8 together with a road map.

FIG. 3A shows a background information table stored in the external storage device 2. This background information table stores background information of lakes, parks, golf courses, etc., which occupy a certain amount of area on the road map. The background information table stores background type codes such as lakes, parks, and golf courses, coordinates indicating the maximum and minimum values of the background area in the x-axis direction and the y-axis direction, and the name of the background. Contains the memory address pointer. Taking the case of Lake Sagami as an example, the background information table will be described. In the background information table of Lake Sagami, the background type code is lake, and the coordinates of the maximum and minimum values in the x-axis and y-axis directions of the area of Lake Sagami are P1.
(X1, y1), P2 (x2, y2), P3 (x3, y
In 3) and P4 (x4, y4), the memory addresses storing “Lake Sagami” are set in the name pointers.

FIG. 3B shows an example in which the characters of the background name are arranged based on the background information in the background information table. Taking the Sagami Lake as an example to explain the placement of the name characters,
Coordinates P1 (x1, y1), P2 (x2, y2), P3 of the maximum and minimum values in the x-axis and y-axis directions of the background area of Sagami Lake
From (x3, y3) and P4 (x4, y4), the center coordinates of the area are obtained, and the name character "Lake Sagami" is arranged from the center coordinates.

FIG. 4A shows a road information table stored in the external storage device 2. This road information table stores road information of highways, national roads, prefectural roads, and general roads. Road information tables include highways, national roads,
It includes a road type code such as a prefectural road, the number of connected nodes of the road, a node pointer indicating a memory address storing node information, and an address pointer of a memory storing a road name. Taking the Tomei Expressway as an example, the road information table is explained. In the Tomei Expressway road information table, the road type code is expressway, the number of connected nodes is the number of nodes of the road, and the node pointer is node information. As the memory address, the memory address storing “Tomei Expressway” is set in the name pointer.

FIG. 4B shows an example in which the characters of the road name are arranged based on the road information in the road information table. Taking the above-mentioned Tomei Expressway as an example, the placement of the name characters will be described. The name letters "Tomei Expressway" are placed in character units along the Tomei Expressway drawn according to the node information.

FIG. 5A shows a point information table stored in the external storage device 2. The point information table stores information about what is represented by points on road maps of public facilities and stations. In the point information table,
The type code, the point coordinates (x, y), and the address pointer of the memory that stores the point name are included. Taking the National Diet Building as an example, the point information table will be explained. The type code is the public facility, the point coordinate is the position coordinate on the road map of the National Diet Building, and the name pointer is the memory address storing "National Diet Building". Each is set.

FIG. 5B shows an example in which the characters of the point name are arranged based on the point information in the point information table. Taking the above-mentioned National Assembly Building as an example, the arrangement of the name characters will be described. The name character “National Diet Building” is arranged from the point coordinates (x, y). However, when a mark or the like indicating the point is displayed at the point coordinate (x, y), the point name character is arranged from the immediate left of the branch coordinate (x, y).

FIG. 6 shows an example of division of the display screen according to the display mode. When the vehicle is running, the display screen of the display device 8 cannot be continuously viewed for a long time. Therefore, at a glance, the minimum characters can be uniformly displayed on the entire display screen so that the information required by the occupant can be provided. It is desirable to display. Therefore, as shown in FIG. 6A, in the display mode during traveling, for example, the display screen is divided into 16 parts. On the other hand, when the vehicle is stopped, the occupant can continue to look at the display screen as many times as necessary, and thus more characters can be displayed on the entire screen than when the vehicle is running. In this embodiment, as shown in FIG. 6B, for example, the display screen is divided into 25 in the display mode while stopped. Further, when displaying a menu screen on the display device 8 to select various functions, it is necessary to display many characters on the display screen. In this embodiment, as shown in FIG. Then, for example, the display screen is divided into 36 parts. In any display mode, characters are uniformly arranged on the entire display screen.

FIG. 7 shows a character arrangement table for setting the character arrangement for each divided area of the display screen. This character arrangement table includes background, road, point name type codes, arrangement coordinates (x, y) on the display screen, the number of display characters, and actual display character data.

FIG. 8 is a flow chart showing a display control program executed by the control circuit 5. The operation of the embodiment will be described with reference to this flowchart. The microcomputer of the control circuit 5 starts executing this control program when a main switch (not shown) is turned on. First, in step S1, the display mode of the vehicle is set based on the traveling speed of the vehicle detected by the vehicle speed sensor included in the current position detection device 1, operation information of the input device 3, and the like, and the above-described display mode is set according to the display mode. The display screen is divided into a plurality of areas. In a succeeding step S2, it is determined whether or not the character arranging process has been completed for all the divided areas, and when it is completed, the execution of the program is completed. If not completed, the process proceeds to a step S3. In step S3, as shown in FIG.
The subroutines 11 to 11 are executed to set the character data in each divided area.

FIG. 9 is a flowchart showing a character data setting routine for background information. By executing this subroutine, the character data of the background information is set for each divided area. In step S11, the coordinates indicating the maximum value and the minimum value in the x-axis direction and the y-axis direction of the background area are read from the background information table shown in FIG. Continued Step S12
Then, the center coordinates of the background area are calculated based on the read coordinates. In step S13, the name pointer of the background information table is referred to, and in step S14, the character data of the background name is read from the memory at the address designated by the name pointer. Then, in step S15, the read character data is set in the character arrangement table shown in FIG. 7 for each divided area. In step S16, it is determined whether or not the processing of all the background information tables has been completed, and if completed, the processing returns to step S3 in FIG.
Returning to 11, the above process is repeated.

After the character data of the background information is set in the character arrangement table, the character data setting routine of the road information shown in FIG. 10 is executed to set the character data of the road information for each divided area. In step S21, the node pointer of the road information table shown in FIG. 4A is referred to, and in subsequent step S22, the node information is read from the memory of the address designated by the node pointer. In step S23, the arrangement position of the character along the road is calculated based on the read node information. In step S24, the name pointer of the road information table is referred to, and in the following step S25, one-character data of the road name is read from the memory of the address designated by the name pointer. Then, in step S26,
The read one character data is set in the character arrangement table for each divided area. In step S27, it is determined whether or not the processing of all the road information tables has been completed. If completed, the processing returns to step S3 in FIG. 8. If not completed, the processing returns to step S21 and the above processing is repeated.

After the character data of the road information is set in the character arrangement table, the character data setting routine of the point information shown in FIG. 11 is executed to set the character data of the point information for each divided area. In step S31, the point coordinates are read from the point information table shown in FIG. Step S
In 32, the name pointer of the point information table is referred to, and in the subsequent step S33, character data of the name is read from the memory at the address designated by the name pointer. Then, in step S34, the read character data of the point name is set in the character arrangement table for each divided area. Step S35
Then, it is determined whether or not the processing of all the point information tables is completed, and when the processing is completed, the processing returns to step S3 of FIG.
If not completed, the process returns to step S31 to repeat the above process.

After setting the character data of the background information, road information and point information in the character arrangement table for each divided area, the process proceeds to step S4 in FIG. 8 and the display mode, the display priority of the occupants set by the input device 3, etc. Select the character to be placed according to. In step 5, it is determined whether or not the selected character can be arranged based on the restrictions such as the number of characters that can be displayed in the divided area. If the character can be arranged, the process proceeds to step S6. If not, the process returns to step S4. In step S6, the characters that can be arranged are arranged on the road map and displayed on the display device 8.

The display mode and the number of divisions of the display screen in each display mode are not limited to those in the above embodiment. Further, the number of display characters for each split screen may be changed according to the display mode.

In the configuration of the above embodiment, the external storage device 2 constitutes a storage means, and the control circuit 5 constitutes a display control means, character data search means, screen division means, and display character setting means.

[0023]

As described above, according to the present invention, the display screen is divided into a plurality of areas according to the display mode, and the character to be displayed is set for each of these divided areas and displayed on the road map. Since this is done, the characters can be displayed uniformly on the entire screen, and the road map display screen becomes easier to see. further,
The display screen is divided into the optimal number of divisions depending on at least the display mode when the vehicle is stopped and the display mode when the vehicle is running, so you can check the characters on the road map at a glance by reducing the number of divisions while driving. If so, more information can be displayed by increasing the number of divisions while stopped.

[Brief description of drawings]

FIG. 1 is a complaint correspondence diagram.

FIG. 2 is a block diagram showing the configuration of an embodiment.

FIG. 3 is a diagram showing a background information table and a character arrangement example of background information.

FIG. 4 is a diagram showing a road information table and an example of character arrangement of road information.

FIG. 5 is a diagram showing a point information table and an example of character arrangement of point information.

FIG. 6 is a diagram showing an example of division of a display screen according to a display mode.

FIG. 7 is a diagram showing a character arrangement table for setting character arrangement.

FIG. 8 is a flowchart showing a display control program of a microcomputer.

FIG. 9 is a flowchart showing a character data setting routine of background information.

FIG. 10 is a flowchart showing a road information character data setting routine.

FIG. 11 is a flowchart showing a character data setting routine for dot information.

[Explanation of symbols]

 1 current position detecting device 2 external storage device 3 input device 4 control circuit 5 ROM 6 RAM 7 storage device 8 display device 100 storage means 101 display device 102 display control means 103 character data search means 104, 104A screen division means 105 display character setting means

Claims (2)

[Claims] 1. A vehicle-mounted map display device comprising: storage means for storing road map data; and display control means for displaying a road map on a display based on the road map data read from the storage means. Character data retrieval means for retrieving character data corresponding to the road map in the display range of the display from the road map data read by the display control means, and dividing the display screen into a plurality of areas according to the display mode. Screen division means, and a display character setting means for setting a character to be displayed from the character data searched by the character data search means for each divided area by the screen division means, the display control means, The display character for each of the divided areas set by the display character setting means is displayed by being superimposed on the road map displayed on the display. In-vehicle map display device according to. 2. The on-vehicle map display device according to claim 1, wherein the display mode includes at least a display mode in which the vehicle is stopped and the vehicle is running, and the screen dividing unit is in the display mode in the stopped state and the running mode. An on-vehicle map display device, characterized in that the display screen is divided into an optimum number of divisions according to the display mode in use.