JP3611650B2 - Vehicle map display device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle map display device capable of displaying a road map around a vehicle position on a display device.
[0002]
[Prior art]
When displaying a road map on a display device, a vehicle map display device that displays a road map in a so-called bird's eye view display format that displays a road map around the current location of the vehicle in an enlarged manner from a distance is known (for example, JP-A-2-244188). The device disclosed in the above publication displays a state in which the viewpoint is placed behind the current location of the vehicle and the vehicle is viewed from the viewpoint on the screen of the display device. When such bird's-eye view display is performed, map information around the current location can be enlarged and displayed, and a wide range from the current location to a distant location can be displayed, so that it is easy to visually grasp the connection state of the road network. In addition, a realistic road map can be displayed as if the driver is looking down at the road map.
[0003]
[Problems to be solved by the invention]
Altitude information is usually stored in a map CD-ROM for storing road map data, and a map display method for displaying contour lines using this altitude information or color-coded according to altitude has been conventionally known. Yes. However, when displaying contour lines, it is necessary to read from the map what height each contour line represents, and if you want to know the height of the intermediate position between the contour lines, the adjacent contour lines It is only possible to estimate the altitude from the above, and it is impossible to know the exact altitude. On the other hand, when color-coded display according to altitude, it is difficult to know whether the slope is gentle or steep, and it is necessary to know in advance which color corresponds to what altitude. Thus, the conventional map display method has a problem that the altitude of each point on the map cannot be intuitively grasped.
[0004]
On the other hand, the bird's eye view display method is a method for displaying a state where the road map is looked down obliquely from above, so if the altitude information stored in the map CD-ROM is used, each map information on the road map is three-dimensionally displayed. It is also possible to display. For example, in the three-dimensional graphic display method disclosed in Japanese Patent Application Laid-Open No. 5-101163, the interval between the grid component points on the map data is changed according to the distance from the viewpoint, and 3 A method for generating a dimensional figure is disclosed.
[0005]
However, in the case of the above publication, since the height is calculated for all the selected grid constituent points, it takes time to generate a three-dimensional figure, that is, to draw a map, and the usability is deteriorated. In addition, when the map information is displayed in three dimensions, a larger amount of display area is required as compared with the case where the map information is displayed two-dimensionally, and therefore the amount of map information that can be displayed on one screen may be reduced.
[0006]
An object of the present invention is to provide a map display device for a vehicle that can display a bird's eye view with a sense of presence and excellent visibility with a simple process.
[0007]
[Means for Solving the Problems]
The present invention will be described with reference to FIG. 1 showing an embodiment of the present invention. The present invention includes a road map storage means 3 for storing road map data relating to a road map, and an area around the current location on the road map. Bird's-eye view data conversion for reading out a predetermined range of road map data from the road map storage means 3 and converting it into bird's-eye view data so that a bird's-eye view looking down on the road map with a predetermined look-down direction and angle from the selected viewpoint is displayed on the display device the vehicle map display and means, the road map data includes altitude information corresponding to each point on a road map, the point is the bird's-eye view data converting means having a high degree or more advanced criteria highly have line conversion to bird's-eye view data based on the altitude information included in the road map data to be displayed three-dimensional bird's-eye view according advanced less than the reference altitude For point having modifies the altitude information included in the road map data to be displayed as a constant altitude point at a predetermined constant high altitude information, intends row conversion of the bird's-eye view data on the basis of the corrected altitude information Is.
In the first aspect of the invention, since the road map storage means 3 composed of a map CD-ROM or the like generally includes altitude information corresponding to each point on the road map, this altitude information is used. The altitude of each point is detected, and only a point having an altitude higher than the reference altitude is displayed in 3D according to the altitude. As a result, the map information to be stereoscopically displayed is limited to improve the map drawing speed.
[0008]
The invention described in claim 2 is a road map storage means 3 for storing road map data relating to a road map, and looks down the road map with a predetermined look-down direction and a look-down angle from a viewpoint placed above the current location on the road map. A vehicle map display device comprising: a bird's eye view data conversion means for reading out a predetermined range of road map data from the road map storage means 3 and converting it into bird's eye view data so that the bird's eye view is displayed on the display device. The data includes altitude information corresponding to each point on the road map. Of the altitude information included in the road map data in a predetermined range read from the road map storage means 3, Equipped with altitude information correction means that corrects everything to altitude information at a predetermined altitude, and points with altitudes above the standard altitude are included in the road map data That performs conversion of on the basis of altitude information to the bird's-eye view data so as to display the three-dimensional bird's-eye view, for other points constitute a bird's-eye view data converting means to perform a conversion into the bird's-eye view data as constant altitude is there.
In the invention according to claim 2, of the altitude information included in the road map data in advance, all the altitude information less than the standard altitude is corrected to a predetermined constant altitude (for example, 0 meters), The points are displayed three-dimensionally according to the altitude, and the other points are displayed two-dimensionally.
[0009]
In the section of the means for solving the above-described problems for explaining the configuration of the present invention, the drawings of one embodiment of the present invention are used for easy understanding of the present invention. It is not limited to the form.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a block diagram of an embodiment of a map display device for a vehicle according to the present invention. In FIG. 1, 1 is a vehicle speed sensor that detects the traveling speed of a vehicle, and 2 is a current position detection device that detects the current position of the vehicle. The current location detection device 2 detects the current location of the vehicle using the vehicle speed sensor 1, an orientation sensor that detects the traveling direction of the vehicle, a GPS sensor that detects a GPS signal from a GPS (Global Positioning System) satellite, or the like. Reference numeral 3 denotes a map storage memory for storing road map data, which is composed of a large-capacity recording medium such as a CD-ROM. As will be described later, it is assumed that the road map data includes position coordinates and altitude information of each point on the road map.
[0011]
A control circuit 4 controls the entire apparatus and includes a microprocessor and its peripheral circuits. 5 is an input device for inputting the destination of the vehicle, 6 is a bird's eye view data memory for temporarily storing road map data for bird's eye view display, and 7 is an image memory for storing image data for display on the display device 8. The image data stored in the image memory 7 is appropriately read out and displayed on the display device 8.
[0012]
FIG. 2 is a flowchart showing a bird's eye view display process of the control circuit 4, and the operation of the present embodiment will be described below based on this flowchart. The control circuit 4 starts the process of FIG. 2 when the ignition key is operated to the ignition on position.
[0013]
In step S <b> 1 of FIG. 2, the vehicle position is detected using the current position detection device 2. In step S2, based on the vehicle position detected in step S1, a viewpoint position when displaying a bird's eye view, a look-down angle from the viewpoint, and the like are set. When the user inputs a bird's eye view scale or the like via the input device 5, the viewpoint position and the like are set in consideration of the input information.
[0014]
In step S3, a map range to be displayed on the display device 8 is calculated based on the setting content of step S2. In step S4, road map data corresponding to the calculated map range is read from the map storage memory 3.
[0015]
FIG. 3 is a diagram showing a data structure of road map data stored in the map storage memory 3. In the road map data, X-axis coordinate data, Y-axis coordinate data, and altitude data are stored for each point (node) as shown in the figure. In step S4, for example, point A → point B →. Road map data is read in the order of NN.
[0016]
In step S5, altitude information of each point included in the read road map data is extracted in order. For example, in the example of FIG. In step S6, it is determined whether or not the altitude at the point extracted in step S5 is greater than or equal to a predetermined reference altitude h meter. If it is less than the reference altitude h meter, the process proceeds to step S7, and the altitude at that point is changed to 0 meter. .
[0017]
If it is determined in step S6 that the altitude is higher than the reference altitude h meters, or if the process in step S7 is completed, the process proceeds to step S8, and it is determined whether or not the processes in steps S5 to S7 have been performed for all points. . If the determination in step S8 is negative, the process returns to step S5, and if the determination is positive, the process proceeds to step S9.
[0018]
In step S9, the road map data is converted into bird's eye view data taking into account the altitude information included in the road map data and the altitude information corrected in step S7. In other words, for points with altitudes higher than the standard altitude h meters, conversion to bird's eye view data is performed based on the altitude information contained in the road map data, and for altitudes below the standard altitude h meters, the altitude is converted to 0 meters. Do.
[0019]
In step S10, the converted bird's-eye view data is converted into image data and stored (drawn) in the image memory 7. Thereby, a bird's-eye view as shown in FIG. 4A is displayed on the display device 8. That is, a point where the altitude is lower than the reference altitude h meter is displayed in a plane, and a point where the altitude is higher than the reference altitude h meter is displayed in a three-dimensional manner. In step S11, the vehicle position is detected again to determine whether or not the vehicle position has changed. If the vehicle position has not changed, the process stays at step S11, and if it has changed, the process returns to step S2.
[0020]
FIG. 5 is a diagram for simply explaining the processing of FIG. 2, and the processing of FIG. 2 is summarized using FIG. 5. First, road map data in a range to be displayed is read from the map storage memory 3, altitude information included in the read road map data is detected, and each point on the road map has a reference altitude h meter (see FIG. 5A). It is determined whether or not it is equal to or higher than the dotted line. And about the area | region (black area | region of FIG.5 (b)) below reference | standard height h, let altitude be 0 meters like FIG.5 (c).
[0021]
Thus, in the present embodiment, when displaying a bird's-eye view, only the map area above the reference altitude is displayed in a three-dimensional manner, so that a bird's-eye view with a sense of reality can be obtained as compared to the case of not displaying a three-dimensional display as shown in FIG. Can be displayed. In addition, since the map information to be stereoscopically displayed is limited to those having a reference altitude of h meters or more, a bird's-eye view can be drawn at a high speed, and the map information displayed on one screen by the stereoscopic display is not limited.
[0022]
In the above embodiment, the user may arbitrarily change the reference value h that is a reference for determining whether or not to perform stereoscopic display. Further, it may be possible to select whether or not to perform a stereoscopic display. In the embodiment described above, a specific building or the like existing on the map may be three-dimensionally displayed even if it is below the reference altitude h.
[0023]
In the embodiment thus configured, the map storage memory 3 is the road map storage means, step S9 in FIG. 2 is the bird's eye view data conversion means, and step S7 in FIG. 2 is the altitude information correction means. Correspond.
[0024]
【The invention's effect】
As described above in detail, according to the present invention, when a bird's-eye view is displayed, a spot having an altitude that is higher than the reference altitude is stereoscopically displayed according to the altitude, so that a realistic bird's-eye view can be drawn at high speed. Further, since the map information to be stereoscopically displayed is limited, the amount of map information displayed on one screen can be increased. Furthermore, since all points below the reference altitude are converted to bird's eye view data as the same altitude, the conversion process to bird's eye view data can be simplified and the map drawing speed can be improved.
[Brief description of the drawings]
FIG. 1 is a block configuration diagram of an embodiment of a map display device for a vehicle according to the present invention.
FIG. 2 is a flowchart showing a bird's eye view display process of a control circuit.
FIG. 3 is a data configuration diagram of road map data stored in a map storage memory.
4A is an example of a bird's eye view display in which a part of map information is stereoscopically displayed, and FIG. 4B is a diagram showing an example of a bird's eye view display in which all map information is displayed in a plane.
FIG. 5 is a diagram for simply explaining the processing of FIG. 2;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Vehicle speed sensor 2 Present location detection device 3 Map memory 4 Control circuit 5 Input device 6 Bird's eye view data memory 7 Image memory 8 Display device

Claims (2)

Road map storage means for storing road map data relating to the road map;
A predetermined range of the road map data from the road map storage means is displayed on the display device so that a bird's eye view looking down the road map at a predetermined look-down direction and a look-down angle from a viewpoint placed above the current location on the road map is displayed. And a bird's-eye view data conversion means for reading out and converting it into bird's-eye view data,
The road map data includes altitude information corresponding to each point on the road map,
The bird's-eye view data converting means, said conversion based on said altitude information included in the road map data into the bird's-eye view data so the point with a high degree of more than the reference altitude in accordance with altitude steric bird's-eye view is displayed There row, the point with a high degree of less than the reference altitude is modified to the said altitude information a predetermined constant altitude altitude information included in the road map data to be displayed as a point of constant altitude, altitude and the modified vehicle map display device comprising a row Ukoto conversion to the bird's-eye view data on the basis of the information. Road map storage means for storing road map data relating to the road map;
A predetermined range of the road map data from the road map storage means is displayed on the display device so that a bird's eye view looking down the road map at a predetermined look-down direction and a look-down angle from a viewpoint placed above the current location on the road map is displayed. And a bird's-eye view data conversion means for reading out and converting it into bird's-eye view data,
The road map data includes altitude information corresponding to each point on the road map,
Altitude information correcting means for correcting all altitude information less than a reference altitude into altitude information of a predetermined constant altitude among the altitude information included in the road map data in the predetermined range read from the road map storage means. ,
The bird's eye view data conversion means performs conversion to the bird's eye view data so as to display a three-dimensional bird's eye view based on the altitude information included in the road map data for a point having an altitude equal to or higher than the reference altitude, A map display apparatus for a vehicle, which converts the bird's eye view data as the constant altitude for points other than the above.

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