JPH07334077A - On-vehicle navigation device - Google Patents

Abstract

PURPOSE:To quickly observe a map picture of a distant area. CONSTITUTION:A map picture of the area, in which a vehicle is located, is displayed on the screen of a CRT display 4 in a head up manner along with a vehicle location mark employing the map data having a 1/12,500 scale specified by the user and stored in a CD-ROM 1. When the user pushes a scroll key to conduct a map scroll, the device is put into a scroll mode. A map picture drawing section 15 first draws the map picture, whose center coordinates continuously change for every prescribed distance, on a video RAM 16 in a head up manner employing the map data having a user specified 1/12,500 scale and displays the picture on the screen. When the scroll key is continuously pushed over a prescribed period, the map picture, whose center coordinates continuously change for every prescribed distance, is drawn on the RAM 16 in a north up manner employing the map data having a 1/50,000 scale, which is two steps smaller and the picture is displayed on the screen.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle-mounted navigation device, and more particularly to a map scroll for drawing and displaying a map image whose center coordinates continuously change in accordance with a map scroll operation made by a scroll key, a joystick or the like. The present invention relates to a vehicle-mounted navigation device having a function.

[0002]

2. Description of the Related Art There is a vehicle-mounted navigation device that displays a vehicle position on a map image to provide driving guidance.
With the spread of the highway network, it is now possible to easily drive long distances.By using an on-vehicle navigation device, it is possible to drive on the road without mistakes even in strange areas, and to bypass traffic congestion appropriately. It has excellent convenience.
In this vehicle-mounted navigation device, a vehicle position is detected by satellite navigation or self-contained navigation, map data including the vehicle position is read from a map data storage medium such as a CD-ROM, an IC memory card, etc., and a map image including the vehicle position is displayed on the screen. Is drawn, and a vehicle position mark is drawn so as to overlap a portion corresponding to the vehicle position on the map image.

By the way, when a scroll operation is carried out with a scroll key, a joystick or the like in the on-vehicle navigation device, the map image is rewritten so that the center coordinates continuously change in the scroll operation direction, and the map is moved continuously. There is a scroll function, tourist spots, customer homes,
When going to a desired place such as a friend's house for the first time, the user can scroll the map in advance to confirm the location of the desired place on the map and the roads around the desired place.

Specifically, for example, in a state where a map image centering on the vehicle position is drawn together with the vehicle position mark using map data of a scale specified by the user (navigation mode), up, down, left, When any one of the four azimuth scroll keys consisting of the right key is operated, for example, the right key, the in-vehicle navigation device enters the map scroll mode, and as shown in FIG. 10, on the current map image,
The coordinates that are apart from the center coordinates (longitude, latitude) by a fixed distance (fixed length L on the screen) in the right direction are calculated, and the calculated coordinates become a new center, and the scale of the user-specified scale is calculated. Redraw the map image using the map data, and after that, as long as the right key operation (press) continues, at regular intervals,
Draw a map image whose center coordinates continuously change to the right by a fixed distance. As a result, it is possible to display on the screen the map image of the portion of the map image last viewed in the navigation mode that is extended to the right. Similarly, if you operate the left key, the map image of the part extended to the left can be displayed on the screen, and if you operate the up key (down key), the map image of the part extended to the up direction (down). Since it can be displayed on the screen, it is possible to easily see the map image in any direction from the vehicle position.

[0005]

However, in the conventional map scroll function, when it is desired to see a map image far from the area of the map image immediately after switching to the map scroll mode, the map scroll operation must be performed for a long time. It was very inconvenient because I could not see the map image of the desired area. In view of the above, an object of the present invention is to provide a vehicle-mounted navigation device that can quickly see a map image of a distant area. Another object is to provide a vehicle-mounted navigation device that facilitates map scroll operation.

[0006]

SUMMARY OF THE INVENTION In the present invention, the above-mentioned problem is solved by the following: map information storing means for storing map information by scale, scale specifying means for performing map scale specifying operation, and map scrolling operation for map scrolling operation. And a display unit for displaying a map image, and a map image drawing unit for drawing a map image whose center coordinates continuously change according to the map scroll operation in the map scroll mode and displaying the map image on the display unit. In the navigation device for a map, the map image drawing means initially draws a map image whose center coordinates continuously change in accordance with the map scroll operation using the map information of the scale specified by the scale specifying means in the map scroll mode. , When the user performs the map scroll operation continuously for a certain period of time or later, the map scroll is performed based on the large scale map information. Center coordinates in accordance with the operation is achieved by drawing continuously change map image.

[0007]

According to the present invention, in the map scroll mode,
First, using the map information of the scale specified by the scale specifying means, draw a map image whose center coordinates continuously change according to the map scroll operation, and when the user continuously performs the map scroll operation for a certain period of time, thereafter, A map image whose center coordinates continuously change is drawn according to a map scroll operation based on map information with a large scale. As a result, when the user performs a scroll operation continuously for a certain period of time or more, the map image is switched to a larger scale, so that even a map image of a distant area can be quickly displayed on the screen.
It is possible to quickly confirm the location of the desired place and the roads around the desired place.

According to another aspect of the invention, in the map scroll mode, the map information of the scale designated by the scale designating means is first used, and when the scale is smaller than a certain level, the heading-up is such that the vehicle azimuth direction is upward. When the scale is larger than a certain scale, draw a map image in which the center coordinates continuously change according to the map scroll operation by north-up with the north facing upward, and when the user continuously performs the map scroll operation for a certain period of time, , A map image whose center coordinates continuously change according to a map scrolling operation is drawn by North Up based on map information with a large scale. As a result, even if the map image is initially displayed in the head-up mode, the map scrolling operation is continued for a certain period of time or more, and after switching to a large scale, the north-up map image that the user is accustomed to using on a map book etc. Is displayed,
The map scroll operation becomes easy.

According to still another aspect of the present invention, in the map scroll mode, the map information of the scale initially designated by the scale designating means is used, and when the scale is smaller than a certain level, the head in which the vehicle azimuth direction is directed upward is used. Up, when the scale is larger than a certain scale, draw a map image in which the center coordinates continuously change in the map scroll operation direction according to the map scroll operation by north up, and when the user performs the map scroll operation continuously for a certain period of time, After that, by north-up based on the map information with a large scale, while the map scroll operation continues, a map image in which the central coordinates continuously change in the previous change direction is drawn, and the map scroll operation is temporarily interrupted. When it is restarted after being restarted, the center coordinates change continuously in the map scroll operation direction according to the map scroll operation. To draw a map image. This allows
Initially, the map image with the vehicle direction facing upward was displayed, but when the map image with the north facing upward at a large scale was displayed because the map scroll operation was continued for a certain period of time or more, the same map image was displayed before the scale was changed. While the map scroll operation in the direction continues, you can continue to scroll the map in the same map scroll azimuth direction, so for the map image displayed in the original head-up,
If the direction of the desired location is known, the map image displayed in the north up mode can be scrolled in the direction of the desired location without changing the scroll operation direction. easy.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an overall configuration diagram of a vehicle-mounted navigation device according to an embodiment of the present invention. 1 is CD-ROM
Therefore, map data divided into predetermined longitude widths and latitude widths by scale is stored. Reference numeral 2 denotes an operation panel, which is a four-direction scroll including a navigation mode setting key, an enlargement / reduction key for designating a scale of a map image, and up / down / left / right keys 2a to 2d for performing a map scroll operation. Equipped with keys etc. 3 is a GPS receiver that detects the vehicle position by satellite navigation using GPS satellites, and periodically detects the vehicle position (longitude, latitude) and vehicle direction,
It outputs vehicle position data and vehicle direction data. 4 is CR
The T display device displays a map image around the vehicle position together with the vehicle position mark on the screen, or displays a map image whose center coordinates continuously change according to a map scroll operation together with a cursor mark.

Reference numeral 10 denotes a navigation controller having a microcomputer configuration, and in the navigation mode, the CD-RO is based on the vehicle position data detected by the GPS receiver 3.
A map image around the vehicle position is drawn together with the vehicle position mark using the map data of M1 and displayed on the CRT display device 4, or in the map scroll mode, the center coordinates are continuous according to the map scroll operation by the scroll key. The map image that changes to is drawn together with the cursor mark and displayed on the screen. 11 is a CD-ROM 1
A buffer memory for temporarily storing the map data read from, 12 is a cursor coordinate calculation unit that calculates the cursor coordinates that change according to the operation of the scroll key in the map scroll mode, and 13 is up / down / down in the map scroll mode. Of the left / right keys 2a to 2d, a timer that measures the operation duration of the same key and outputs a time-up signal when a certain time is exceeded, and 14 is a scale management unit that manages the scale.

Reference numeral 15 denotes a map image drawing section, which inputs vehicle position data and vehicle direction data detected by the GPS receiver 3 in the navigation mode, and is designated in advance by the user from the CD-ROM 1 with the enlargement / reduction key. Read the map data around the vehicle position at a reduced scale into the buffer memory 11,
Using the read map data, a map image centering on the vehicle position is drawn in a video RAM described later, and a vehicle position mark is also drawn. In the navigation mode, the map image drawing unit 15 draws a map image by head-up with the vehicle azimuth direction facing upward when the scale specified by the user with the enlargement / reduction key is larger than 1/25000 or less, and the user specifies it. When the scale is smaller than 1 / 50,000 or more, the map image is drawn by north-up with north facing upward (see Fig. 2).

In the map scroll mode, the map image drawing unit 15 initially operates (presses) any one of the up, down, left, and right keys 2a to 2d, for example, the right key (left key). Then, based on the cursor coordinates calculated by the cursor coordinate calculation unit 12, a constant distance (fixed length on the screen) in the right direction (left direction) with respect to the center coordinates (longitude, latitude) on the current map image. The position apart by L) becomes the new center, and the map image is redrawn with the head-up or north-up according to the scale using the map data of the scale specified by the user as in the navigation mode. Draw the cursor mark on the center of the map image, and then, while the operation of the right key (left key) continues, the center coordinates move to the right by a fixed distance (left direction) at regular time intervals.
A map image that changes continuously is drawn, and a cursor mark is drawn on the center of the map image. When the up key (down key) is operated, on the current map image,
The map data at the scale specified by the user is set so that the position apart from the center coordinate (longitude, latitude) by a certain distance (a certain length L on the screen) in the upward direction (downward direction) becomes the new center. Use the same as in the navigation mode to redraw the map image at the head-up or north-up according to the scale and draw the cursor mark at the center, and while the operation of the up key (down key) continues. , Draws a map image whose center coordinates continuously change upward (downward) by a fixed distance and draws a cursor mark at the center.

Then, in the map scroll mode, up,
When any one of the down, left, and right keys, for example, the right key, is operated (pressed) continuously for a certain period of time and the timer 13 times out, thereafter, the scale is smaller than the scale up to that point (here, 1). Within the range of 100000 or less, 2 than before
Change to a small scale) and draw a map image by North Up.

A video RAM 16 has a storage area for one screen and stores a map image together with a vehicle position mark and a cursor mark. A reference numeral 17 reads an image drawn in the video RAM 16 and converts it into a predetermined video signal. CRT
It is an image conversion unit for outputting to the display device 4.

3 to 5 are flow charts showing the operation of the navigation controller 10, and FIGS. 6 and 7 are explanatory views of screen display examples, which will be described below with reference to these figures. In this case, the CD-ROM 1 has a smaller scale from 1
It is assumed that map data of four kinds of scales of / 100,000, 1/50000, 1/25000, and 1/12500 are stored. Navigation Mode After the power is turned on, the GPS receiver 3 periodically detects the current vehicle position and vehicle azimuth and outputs these data to the navigation controller 10. On the other hand, the navigation controller 10 is turned on and automatically enters the navigation mode (step 101 in FIG. 3), and the scale management unit 14 sets the scale data A to the minimum scale for which map data is prepared in the CD-ROM 1 (step). 102). Here, A = 1/12500. Next, the map image drawing unit 15 inputs the vehicle position data and the vehicle direction data from the GPS receiver 3, reads the map data of the scale A including the vehicle position from the CD-ROM 1 into the buffer memory 11, and reads the read map data. Based on the vehicle position based on 1
When the scale A is 1/25000 or more (here, the scale is 1/12500 and 1/25000), the map image for the screen is scaled up by head-up with the vehicle azimuth direction facing upward.
Is 1/50000 or less, the scale here is 1 / 50,000 and 1
/ 100,000) is drawn in the video RAM 16 by north up with north facing upward (steps 103, 10).
4, 105 or 104, 106) and also the video RA
A vehicle position mark in which the vehicle azimuth direction on the map image is oriented is drawn at the center of M16 (step 107). Video R
The image drawn on the AM 16 is read by the image conversion unit 17, output to the CRT display device 4 and displayed on the screen (step 108).

Thereafter, it is checked whether or not the scale change operation is performed by the user with the enlargement / reduction key (step 109), and if so, the scale management unit 14 changes A according to the operation (step 110), If not, A is left as it is (NO in step 109). Further, it is checked whether or not the scroll key has been operated by the user (step 111). If not, the process returns to step 103 to repeat the same processing. Therefore, a map image centering on the vehicle position is displayed on the screen together with the vehicle position mark, and the map image on the screen scrolls as the vehicle moves, so that the user can always confirm the own vehicle position on the map. it can. Since a detailed map image with a large scale is displayed with the vehicle traveling direction facing upward, it is easy to compare the roads on the map with the actual roads. Since it is displayed, it is possible to confirm the whereabouts of the main road in a familiar direction when confirming the map with a map book (see FIG. 2).

Map Slocool Mode In a state where a map image centering on the vehicle position is displayed head-up based on the map data of the scale A = 1/12500 with the east direction, which is the current vehicle azimuth direction, facing upward. 6 (1) (screen state), in order to confirm the whereabouts of the desired place in the area far away from the current position and the road around the desired place, when the right key 2d is pressed, the navigation controller 10 enters the map scroll mode ( 4, the cursor coordinate calculation unit 12 sets the current vehicle position as the initial value of the cursor coordinates (step 20).
2). Since the scale A preset by the user is 1/25000 or more, the cursor coordinate calculation unit 12
Is a coordinate system with the east direction, which is the current vehicle azimuth direction, facing upward, and is a constant distance L / right from the cursor coordinates up to that point.
Coordinates separated by A (mm) are calculated and set as new cursor coordinates (steps 203 and 204).

Then, the map image drawing unit 15 is a CD-RO.
The map data of the scale A including the cursor coordinates is read from M1, and the map image of the scale A with the cursor coordinates as the center and the east facing upward is drawn in the video RAM 16 by the head-up (step 205), and the map image is displayed at the center of the map image. A cross-shaped cursor mark is drawn (step 206). Video RA
The image of M16 is read by the video conversion unit 17, converted into a video signal, output to the CRT display device 4, and displayed on the screen (step 207, see FIG. 6 (2)). Here, if L = 1 (mm), the map image moves 1 (mm) on the screen, and the center moves 1 × 12500 (mm) in the south direction (to the right of the screen), but the map image itself is opposite. Scroll to the north (to the left of the screen).

Next, the navigation controller 10 checks whether the timer 13 outputs a time-up signal (step 301 in FIG. 5). First timer 1
Since No. 3 does not perform the time counting operation yet and is NO, subsequently, it is checked whether the same right key 2d is still pressed (step 302). If YES, the timer 13 does not perform the time counting operation ( If NO in step 303), the timer 13 is started to measure a fixed time (step 304). Then, returning to step 204 of FIG. 4, the cursor coordinate calculation unit 12 uses the coordinate system with the east facing upward, and moves a predetermined distance L / A (m
m) is calculated to be a new cursor coordinate, and the map image drawing unit 15 draws the map image with the center changed by a certain distance in the south direction (right direction of the screen) at the scale A together with the cursor mark of the center. Then, the screen is displayed (steps 205 to 207). Next, the navigation controller 10 checks whether the time-up signal is input from the timer 13 (step 301 in FIG. 5). If not, it is checked whether the same right key 2d is continuously pressed (step 302), and if YES, the timer 13
Is in the time counting operation, the process returns to step 204 in FIG. As a result, the map image on the screen is scrolled so that the central coordinates continuously change in the right direction of the screen, which is the scroll operation direction.

If the user continues to press the right key 2d for a certain time or longer to scroll to a region far away to the south, the timer 1 is activated when a certain time has elapsed from the start of the pressing.
3 times up and outputs a time-up signal. Then, the navigation controller 10 determines YES in step 301 of FIG. 5, and the scale management unit 14 reduces A by two steps to 1/50000 (step 305). Then, the cursor coordinate calculation unit 12 calculates a coordinate that is a certain distance L / A (mm) away from the previous cursor coordinate in the rightward direction in the coordinate system with north facing upward, and sets it as a new cursor coordinate ( Step 208 of FIG. 4). Further, the map image drawing unit 15 reads the map data of the scale A including the cursor coordinates from the CD-ROM 1 and draws the map image of the scale A with the cursor coordinates at the center and the north facing upward in the video RAM 16 by northing up. (Step 209), a cross cursor mark is drawn in the center of the map image (Step 210). The image in the video RAM 16 is the image conversion unit 1.
It is read by 7, converted into a video signal, output to the CRT display device 4, and displayed on the screen (step 211, see FIG. 7 (1)).

After that, the navigation controller 1
For 0, it is checked whether the scroll key is pressed (step 212), in which the user once presses the right key 2
When the pressing of d is stopped, it is judged as NO, and in this case,
Then, it is checked whether the scale change operation is performed by the enlargement / reduction key (step 213). If NO, it is checked whether the navigation mode setting key is pressed (step 215). Return to 212.

When the user wants to display the southern region on the screen when the map image is switched to North Up, the down key 2b corresponding to South in the map book may be pressed. When the user presses the down key 2b, the navigation controller 10 determines YES in step 212, and the cursor coordinate calculation unit 12 uses the coordinate system with north facing upward, and the cursor coordinate calculation unit 12 moves downward by a predetermined distance L / Coordinates separated by A (mm) are calculated as new cursor coordinates (step 208 in FIG. 4). Further, the map image drawing unit 15 is C
The map data of the scale A including the cursor coordinates is read out from the D-ROM 1, and the map image of the scale A with the cursor coordinates as the center and the north facing upward by north up is recorded in the video RAM.
16 is drawn (step 209), and a cross cursor mark is drawn in the center of the map image (step 210). The image in the video RAM 16 is read by the image conversion unit 17 and converted into an image signal, and the CRT display device 4
And is displayed on the screen (step 211, FIG. 7).
(See (2)).

When L = 1 (mm), the map image moves 1 (mm) on the screen and the center moves 1 × 50000 (mm) in the south direction (downward of the screen), and the map image itself Scroll in the opposite north direction (upward on the screen). After that, when the user continues to press the down key 2b, the map image on the screen scrolls so that the central coordinates continuously change in the downward direction of the screen, which is the scroll operation direction. At this time, the scale A
Since it is smaller in two steps from when the map is switched to the map scroll mode, you can quickly display the area containing the desired place on the screen, check the location of the desired place, and the roads around the desired place. Can be confirmed.

After setting the map scroll mode,
If the user temporarily stops the scrolling operation before the timer 13 times out, the timer 13 stops counting the time (steps 301, 302, 306 in FIG. 5), and then performs the scale changing operation with the enlarge / reduce key. At this time, after the scale management unit 14 changes the scale A according to the operation (steps 307 and 308), the process proceeds to step 209 of FIG. 4, and the map image drawing unit 15 uses the map data of the scale A after the change, A map image centered on the current cursor coordinates is drawn in the video RAM 16 by north-up with north facing upward. Then, the cursor mark is overlaid on the center of the map image to draw it and display it on the screen (steps 210 and 21).
1). Thereafter, the map image by North Up is scrolled according to the scroll operation. Even when the scale is increased or decreased by the enlargement / reduction key after switching to the north-up, the scale management unit 14 can be used.
After changing the scale A according to the operation (Step 21
3, 214), and proceed to step 208 in FIG.

As described above, when the user changes the scale after changing to the map scroll mode, the map image is displayed in the north-up, and the user can see the map in a familiar direction with a map book or the like. , Scroll key up, down,
By operating the left and right keys 2a to 2d, the map can be scrolled in the natural north, south, west, and east directions that are commonly used in a map book or the like, which facilitates the operation. Since it is not the case to check the road near the vehicle position when changing the scale, there is no particular inconvenience even if the map image is not displayed in the head-up. After the map scroll operation is completed, the navigation mode setting key can be pressed to return to the original navigation mode (step 2 in FIG. 4).
15 or step 309 in FIG. 5, step 10 in FIG.
1).

According to this embodiment, in the map scroll mode, when the user performs a scroll operation continuously for a certain period of time with any one of the up, down, left and right keys 2a to 2d, the scale is reduced from the beginning. Since it is automatically switched to a large map image of, the map image of a distant area can be quickly displayed on the screen, and the location of the desired place and the roads around the desired place can be quickly confirmed. Moreover, even if the map image is displayed in the head-up mode at the beginning of the map scroll mode, the user has become accustomed to using the map book etc. after switching to a large scale due to the map scroll operation being continued for a certain period of time. Since the north-up map image is displayed, the map scroll operation becomes easy.

FIG. 8 is a flow chart showing the map scrolling operation of the navigation controller 10 according to the modification of the above-mentioned embodiment, and FIG. 9 is an explanatory diagram of a screen display example. FIG. 8 shows the processing until the process proceeds to step 212 of FIG. 4 after YES in step 301 of FIG. 5 in the above embodiment. In this modified example, when the map image is displayed by the head-up at the beginning of the map scroll mode, the user presses any one of the up, down, left, and right keys 2a to 2d for a certain time or more. Continue scrolling,
When the timer 13 times out, the scale management unit 14 reduces the scale A by two steps (step 40 in FIG. 8).
1, 402), when the same key is still pressed, the cursor coordinate calculation unit 12 uses a coordinate system in which the vehicle azimuth direction is upward, and a predetermined distance L / in the direction of the pressed key from the cursor coordinates up to that point. Coordinates separated by A (mm) are calculated and set as new cursor coordinates (steps 403 and 40).
4). Further, the map image drawing unit 15 reads the map data of the scale A including the cursor coordinates from the CD-ROM 1 and draws the map image of the scale A with the cursor coordinates at the center and the north facing upward in the video RAM 16 by northing up. (Step 405), a cross-shaped cursor mark is drawn at the center of the map image (Step 406). The image in the video RAM 16 is read by the video conversion unit 17, converted into a video signal, output to the CRT display device 4, and displayed on the screen (step 407, see FIG. 9).

After that, when the user continues to press the same key, the cursor coordinate calculation unit 12 uses the coordinate system in which the north is directed upward, and the cursor coordinate calculation unit 12 moves a predetermined distance L / A from the cursor coordinates so far in the direction of the pressed key. Coordinates separated by (mm) are calculated as new cursor coordinates (steps 403, 40).
4), the map image drawing unit 15 reads the map data of the scale A including the cursor coordinates from the CD-ROM 1 and draws the map image of the scale A with the cursor coordinates at the center and the north facing upward in the video RAM 16 by northing up. Then, a cross-shaped cursor mark is drawn in the center of the map image and displayed on the screen (steps 406 and 407). Therefore, even if the timer 13 times out while the scroll operation is continued with the same key and the map image is switched to the north-up map image with a smaller scale than before, the central coordinates are continuous in the same azimuth direction as before. The map is scrolled so as to change to (see broken arrow B in FIG. 9).

For example, at the beginning when the map was changed to the slow cool mode, the scale was set so that the head was up and the east was directed upwards A = 1.
A map image of / 12500 is drawn, and the user scrolls the map so that the center coordinates continuously change to the south (right side of the screen) by pressing the right key 2d to view the map of the south area. When the right key 2d is pressed continuously for a certain period of time, the timer 13 times out, and as long as the right key 2d continues to be pressed after that, the scale up A = 1/50000 with north facing up due to north up The map image can be scrolled so that the center coordinates continuously change in the south direction (downward direction of the screen), the scale changes, and even after the display direction changes from head up to north up, the same key The map image displayed in the head-up display can be scrolled in a desired direction by an operation, and since it is not necessary to change the key, the operation is easy.

After the scale and the display direction are changed due to time-up, the up, down, left and right keys 2a to 2d are moved to the upper (north), lower (south), left (west) and right (east) map images. ) If you want to scroll with the same correspondence as
After stopping, for example, when it is desired to see the southern area, the down key 2b may be pressed. Once the scrolling operation is stopped, it is determined NO in step 403 of FIG. 8 and the process proceeds to step 209 of FIG. 4, in which the map image drawing unit 15 draws the map image of the reduced scale A by north up together with the cursor mark at the center, The screen is displayed (210, 211). When the down key 2b is pressed, step 212 in FIG.
After that, the process proceeds to step 208, and the cursor coordinate calculation unit 12
Is a coordinate system with north facing upward, and is a fixed distance L / A from the cursor coordinates up to that point to the south direction corresponding to the down key 2b.
The coordinates separated by (mm) are calculated as new cursor coordinates, and the map image drawing unit 15 reads the map data of the reduced scale A including the cursor coordinates from the CD-ROM 1, the cursor coordinates are the center, and the north is moved to the north. A map image with the scale A facing upward is drawn in the video RAM 16 (step 209), a cross-shaped cursor mark is drawn in the center of the map image, and it is displayed on the screen (steps 210, 211).

According to this modification, the map image with the vehicle azimuth direction facing upward is initially displayed, but the map image with the north facing upward is displayed at a large scale because the map scroll operation is continuously performed for a certain time or longer. In this case, since the map scroll operation can be continued in the same map scroll azimuth direction while the map scroll operation in the same direction continues before the scale is changed, it is displayed in the original head-up. If the direction of the desired location is known with respect to the map image, the map image displayed in the north-up can be scrolled in the direction of the desired location without changing the scroll operation direction on the way, Easy to scroll map.

In the above-mentioned embodiments and modified examples, the case where the map scroll operation is performed by the 4-direction scroll key has been described, but the same can be applied to the case where the map scroll is operated by the 8-direction scroll key or the joystick. . Also, after entering the map scroll mode,
When the scroll operation is continued for a certain time or longer, the map image with a scale smaller by 2 stages than before is displayed, but the map image with a scale larger by 1 stage or a scale image larger than 3 stages is displayed than before. Alternatively, a fixed fixed small scale map image may be displayed.

[0034]

According to the present invention, in the map scroll mode, initially, map information whose center coordinates are continuously changed according to the map scroll operation is drawn by using the map information of the scale specified by the scale specifying means, When the user performs the map scroll operation continuously for a certain period of time or more, thereafter, the map image in which the central coordinates continuously change according to the map scroll operation is drawn based on the map information with a large scale. When scrolling continuously for more than a time, it switches to a map image with a larger scale than before, so you can quickly display even a map image of a distant area on the screen, the location of the desired place and the surrounding roads of the desired place. Can be confirmed promptly.

According to another aspect of the invention, in the map scroll mode, the map information of the scale designated by the scale designating means is initially used, and when the scale is smaller than a certain value, the head-up is set so that the vehicle azimuth direction is upward. When the scale is larger than a certain scale, draw a map image in which the center coordinates continuously change according to the map scroll operation by north-up with the north facing upward, and when the user continuously performs the map scroll operation for a certain period of time, , Even if the map image is initially displayed in the head-up mode, the map image with the center coordinates continuously changing in accordance with the map scrolling operation by Northup based on the large-scale map information is rendered constant. After switching to a large scale due to the map scrolling operation continued for more than an hour, the user usually sees it in a map book etc. And since the map image of the north-up display, it is easy to map scrolling.

According to still another aspect of the invention, in the map scroll mode, the map information of the scale designated by the scale designating means is initially used, and when the scale is smaller than a certain level, the head in which the vehicle azimuth direction is directed upward is used. Up, when the scale is larger than a certain scale, draw a map image in which the center coordinates continuously change in the map scroll operation direction according to the map scroll operation by north up, and when the user performs the map scroll operation continuously for a certain period of time, After that, by north-up based on the map information with a large scale, while the map scroll operation continues, a map image in which the central coordinates continuously change in the previous change direction is drawn, and the map scroll operation is temporarily interrupted. When it is restarted after being restarted, the center coordinates change continuously in the map scroll operation direction according to the map scroll operation. Since it was configured to draw a map image, it initially displayed a map image with the vehicle azimuth direction facing upward, but since the map scroll operation continued for a certain period of time or more, the map image with the north facing upward at a large scale. When displaying, the map can be scrolled continuously in the same map scroll azimuth direction while the map scroll operation is continuing in the same direction before the scale is changed. If the direction of the desired location is known for the displayed map image,
Even if the scrolling operation direction is not changed, the map image displayed in the north-up direction can be scrolled in the direction in which the desired place exists, and the map scrolling operation is easy.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a vehicle-mounted navigation device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a relationship between a scale and a display direction.

FIG. 3 shows a first operation of the navigation controller
2 is a flowchart of.

FIG. 4 is a second diagram showing the operation of the navigation controller.
2 is a flowchart of.

FIG. 5 is a third view showing the operation of the navigation controller.
2 is a flowchart of.

FIG. 6 is an explanatory diagram showing a screen display example.

FIG. 7 is an explanatory diagram showing a screen display example.

FIG. 8 is a flowchart showing an operation of a navigation controller according to a modified example of the present invention.

FIG. 9 is an explanatory diagram showing a screen display example in a modified example.

FIG. 10 is an explanatory diagram of a conventional map scroll operation.

[Explanation of symbols]

 1 CD-ROM 2 Operation panel 2a Up key 2b Down key 2c Left key 2d Right key 3 GPS receiver 4 CRT display device 10 Navigation controller 12 Cursor coordinate calculation unit 13 Timer 14 Scale management unit 15 Map image drawing unit 16 Video RAM 17 Video converter

Claims (3)

[Claims] 1. A map information storage means for storing map information for each scale, and a scale specifying means for performing a map scale specifying operation.
Map scroll operation means for performing map scroll operation,
A vehicle-mounted navigation device including display means for displaying a map image and map image drawing means for drawing a map image whose center coordinates continuously change in accordance with a map scroll operation in the map scroll mode and displaying the map image on the display means. In the map scroll mode, the map image drawing means initially draws a map image in which the central coordinates continuously change according to the map scroll operation using the map information of the scale specified by the scale specifying means, and the user When a map scroll operation is continuously performed for a certain period of time or later, a map image in which the central coordinates continuously change according to the map scroll operation is drawn based on the map information with a large scale. apparatus. 2. A map information storage means for storing map information for each scale, a vehicle direction detection means for detecting a vehicle direction, a scale specification means for performing map scale specifying operation, and a map scroll operation means for performing map scroll operation. A display means for displaying a map image, and a map image drawing means for drawing a map image whose center coordinates continuously change according to the map scroll operation in the map scroll mode and displaying the map image on the display means,
In the vehicle-mounted navigation device, the map image drawing means, in the map scroll mode, initially using the map information of the scale specified by the scale designating means, when the scale is smaller than a certain direction, the vehicle azimuth direction upward When the scale is larger than a certain scale, the head-up makes the north upward and draws a map image in which the center coordinates continuously change according to the map scroll operation, and the user continues the map scroll operation for a certain period or longer. At that time, the vehicle-mounted navigation device is characterized in that, thereafter, a map image whose center coordinates continuously change according to a map scroll operation by north-up is drawn based on map information of a large scale. 3. A map information storage means for storing map information by scale, a vehicle direction detection means for detecting a vehicle direction, a scale specification means for performing a map scale specifying operation, and a map scroll operation means for performing a map scroll operation. A display means for displaying a map image, and a map image drawing means for drawing a map image whose center coordinates continuously change according to the map scroll operation in the map scroll mode and displaying the map image on the display means,
In the vehicle-mounted navigation device, the map image drawing means, in the map scroll mode, initially using the map information of the scale specified by the scale designating means, when the scale is smaller than a certain direction, the vehicle azimuth direction upward When the scale is larger than a certain level, the map image with the center coordinates continuously changing in the map scroll operation direction is drawn by the north up when the scale is larger than a certain scale, and the user continues the map scroll operation for a certain period of time or more. Then, based on the map information with a large scale, the north-up draws a map image in which the center coordinates continuously change in the direction of change until the map scroll operation continues, and the map scroll operation continues. When it is resumed after being interrupted, the center coordinates are changed according to the map scroll operation. The vehicle-mounted navigation device is characterized in that a map image that continuously changes in the operation direction is drawn.