JP5366170B2 - Map display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a map display device capable of performing a stereoscopic map display matched with an undulating state capable of being sensuously recognized by a user. <P>SOLUTION: A control section 102 reads map data including the altitude value of each point on a map read from a hard disk 22 by an HDD 20 and stored in a buffer memory 104. Further, the control section 102 sets an altitude value for three-dimensional display indicating a virtual altitude value in the three-dimensional display of a first point determined in accordance with the difference between the altitude value of a first point and the altitude value of a second point around the first point on the map contained in the map data contained in the map data. A map drawing section 106 draws, on the basis of the altitude value for stereoscopic display, a stereoscopic display image of the map including the first point and displays it on a display 70. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a map display device that performs stereoscopic display of a map.

  A navigation device as a map display device is generally mounted on a vehicle, reads map data corresponding to the position of the vehicle from a map data recording medium such as a hard disk, CD-ROM, DVD-ROM, and the like, and based on this map data. The map image around the vehicle position is displayed on the display device. Further, the navigation device displays the vehicle position mark superimposed on the map image, and further scrolls the map image according to the movement of the vehicle so that the user can grasp the position of the vehicle. It has become.

Some navigation devices have a function of generating and displaying a stereoscopic display image of a map viewed from a predetermined viewpoint position such as above a vehicle position in order to display a more realistic map image. However, if a 3D display image is generated and displayed using the elevation values of each point on the map as they are, it may be difficult for the user to understand the terrain undulation state. For this reason, for example, in the technique described in Patent Document 1, an elevation magnification for highlighting the undulating state of the terrain is obtained, and the elevation magnification at each point is multiplied by the elevation magnification for virtual display for stereoscopic display. A high altitude value is calculated, and a stereoscopic display image of the map is generated and displayed based on the virtual altitude value.
Japanese Patent Laid-Open No. 11-237836

  By the way, when the user perceives the undulation of the terrain, the user often feels that the large undulation portion of the terrain is larger than the actual undulation, and the small undulation portion is smaller than the actual undulation. However, in the technique described in Patent Document 1 described above, the undulation state is highlighted as the terrain undulation state is smaller, and a deviation occurs between the undulation state that the user grasps sensuously. Sometimes.

  An object of the present invention is to solve the above-described problems, and to provide a map display device capable of three-dimensional display of a map that matches a undulation state that a user grasps sensuously.

According to the present invention, a map display device for performing a three-dimensional display of a map has a difference between an altitude value at a first point, which is each point on the map, and an altitude value at a second point around the first point. Map data acquisition means for acquiring map data including an elevation value for stereoscopic display indicating a virtual elevation value in the stereoscopic display of the first point, and the first point included in the map data Display processing means for displaying a stereoscopic display image of a map including the first point on a display unit based on the elevation value for stereoscopic display.

  According to this configuration, when a stereoscopic display is made for the first point on the map, the first point determined according to the difference in elevation value between the first point and the surrounding second point. Based on a virtual elevation value (elevation value for stereoscopic display), a stereoscopic display image of the map is displayed. Therefore, it is possible to display a stereoscopic display image of a map in which the undulation portion of the terrain is larger than the actual undulation, and the small undulation portion is smaller than the actual undulation, and the user grasps sensuously. Can match the undulation state.

According to the present invention, a map display device that performs stereoscopic display of a map includes map data acquisition means for acquiring map data including an elevation value of each point on the map, and each point on the map included in the map data determined in which according to the difference between the altitude value of the second point near the point of elevation and the first of the first point, the three-dimensional indicating a virtual elevation values in the stereoscopic display of the first point 3D display altitude value setting means for setting the display altitude value, and a display for displaying a 3D display image of a map including the first point on the display unit, based on the 3D display altitude value of the first point. And processing means.

  According to this configuration, in the same manner as described above, when the stereoscopic display is made for the first point on the map, the first point determined according to the difference in altitude value between the first point and the surrounding second point. A virtual elevation value (stereoscopic display elevation value) at one point is set, and a stereoscopic display image of the map is displayed based on the stereoscopic display elevation value at the first point. Therefore, it is possible to display a stereoscopic display image of a map in which the undulation portion of the terrain is larger than the actual undulation, and the small undulation portion is smaller than the actual undulation, and the user grasps sensuously. Can match the undulation state.

  From the same point of view, in the map display device according to the present invention, the elevation value for the first stereoscopic display is such that the difference between the elevation value at the first point and the elevation value at the second point is a first predetermined value. A difference between the elevation value for stereoscopic display at the first point and the elevation value for stereoscopic display at the second point is set to be greater than the difference between the elevation values, When the difference between the elevation value at one point and the elevation value at the second point is less than or equal to a second predetermined value, the elevation value for stereoscopic display at the first point and the elevation value are more than the difference between the elevation values. You may make it set so that the difference with the elevation value for stereoscopic display of a 2nd point may become small.

  In the map display device according to the present invention, when the stereoscopic display elevation value setting means designates the display of the stereoscopic display image of the map based on the elevation value for stereoscopic display by the operation of the operation unit, The elevation value for stereoscopic display of the first point may be set.

  According to this configuration, it is possible to set an appropriate elevation value for stereoscopic display and further to display a stereoscopic display image of a map according to a user's request.

  In the map display device according to the present invention, the map data includes an attribute of each point on the map, and the 3D display elevation value setting means specifies the attribute by an operation of an operation unit. In such a case, the elevation value for stereoscopic display of the point having the attribute may be set.

  According to this configuration, for example, only when the point attribute is “mountain”, an appropriate elevation for 3D display according to the user's request such as making a large undulation portion of the terrain larger than the actual undulation It is possible to set a value and display a stereoscopic display image of a map.

  According to the present invention, a virtual elevation value (elevation value for stereoscopic display) corresponding to an elevation difference from a surrounding point is set for a predetermined point, and a three-dimensional map is displayed based on the elevation value for stereoscopic display. By displaying the image, the stereoscopic display image of the map can be matched with the undulation state that the user grasps sensuously.

  Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. FIG. 1 is a diagram showing a configuration of a navigation device to which a map display device of the present invention is applied. A navigation device 100 shown in FIG. 1 is mounted on a vehicle, and includes a main body 10, a hard disk drive (HDD) 20, an operation unit 30, a VICS reception unit 40, a GPS reception unit 50, an autonomous navigation sensor 60, a display 70, and a speaker 80. Consists of.

  The HDD 20 is equipped with a hard disk 22 and reads map data recorded on the hard disk 22. The map data recording medium is not limited to the hard disk 22, and may be a DVD, a CD-ROM, or the like, and a drive corresponding to the recording medium is prepared. The map data is provided for each rectangular area called a figure leaf and specified by the longitude and latitude of the four corners. The map data for each leaf includes information on the scale of the leaf and the longitude and latitude of the four corners of the rectangular area corresponding to the leaf, and is uniquely specified by the longitude and latitude. The map data for each leaf includes map image data of the leaf and road information of a road existing in a rectangular area corresponding to the leaf.

  FIG. 2 is a diagram illustrating an example of road information. A road is represented by a start point and an end point (node) and a straight line (road link) connecting these nodes. The road information includes a node record shown in FIG. 2 (a) and a link record shown in FIG. 2 (b). The node record shown in FIG. 2A is provided for each node. The node number, which is identification information of the node, the coordinates (longitude and latitude) of the node, and a link at which the node is an end portion. And a connection link number that is identification information of (connection link).

  On the other hand, the link record shown in FIG. 2B is provided for each road link. This link record includes a link number that is identification information of a corresponding road link, link attributes such as whether the road link is a general road or a highway, and identification information of a node that is the starting point of the road link. It includes a certain start point node number and an end point node number that is identification information of a node that is the end point of the road link. With these node records and link records, it is possible to specify the position of a road composed of two nodes, a start point and an end point, and a road link connecting these nodes.

  In addition, the map data for each leaf includes information on the point for each point existing in the rectangular area corresponding to the leaf. This point is a position representing a predetermined area (for example, a rectangular area) (for example, the center of the predetermined area), and is set at a predetermined interval.

  FIG. 3 is a diagram illustrating a first example of point information. As shown in FIG. 3, the point information includes a point number that is identification information of the corresponding point, the coordinates of the corresponding point (longitude and latitude), the elevation value for the stereoscopic display of the corresponding point, and the corresponding point is a mountainous area And a point attribute indicating whether it is a plain or the like. Here, the elevation value for stereoscopic display refers to the elevation value of the first point and the elevation values of the points around the first point (second point) for the corresponding point (first point). It is determined according to the difference (elevation value difference). Specifically, the elevation value for stereoscopic display at the first point is equal to the elevation value for stereoscopic display at the first point than the elevation value difference when the elevation value difference is greater than or equal to the first predetermined value. When the difference from the elevation value for stereoscopic display at the point 2 is set to be large, and the elevation value difference is equal to or smaller than a second predetermined value (where the second predetermined value <the first predetermined value), The difference between the elevation value for stereoscopic display at the first point and the elevation value for stereoscopic display at the second point is set to be smaller than the difference in elevation value. On the other hand, when the elevation value difference is larger than the second predetermined value and smaller than the first predetermined value, the elevation value at the first point is directly used as the stereoscopic display elevation value at the first point.

  Here, the elevation value difference can be obtained as follows. For example, when a point is set for each of the rectangular areas as shown in FIG. 4, the first point 201 that is the representative position (center) of the central rectangular area 211 and the first point 201 are surrounded. The difference in altitude value from the second point 202, which is the representative position (center) of the surrounding eight rectangular areas 212, calculates the average value of the altitude values of the eight second points 202, and further the first point It can be obtained by calculating the difference between the altitude value of 201 and its average value. In addition, in order to calculate the average value of the altitude value, it is arbitrary which altitude value of the area is used, and as shown in FIG. 4, the eight rectangular areas 212 around the first point 201 are surrounded. The altitude value of the second point 202 is not limited. For example, the elevation value of a point selected from the second points 202 of these eight rectangular regions 212 may be used, or the elevation value of a point in a region outside the eight rectangular regions 212 may be used.

  On the other hand, FIG. 5 is a diagram illustrating a second example of point information. The point information shown in FIG. 5 includes a point number that is identification information of a corresponding point, coordinates of the corresponding point (longitude and latitude), an altitude value of the corresponding point, and whether the corresponding point is a mountain area or a plain. And a point attribute indicating whether or not there is.

  Again, returning to FIG. The operation unit 30 includes an operation button, a joystick, and the like (not shown), and is operated by the user in setting a destination when searching for a guidance route. The VICS receiving unit 40 receives VICS information including traffic information transmitted from a radio wave beacon or an optical beacon, or multiplexed and transmitted in FM broadcasting. The VICS information is updated and transmitted at a predetermined cycle such as an interval of 5 minutes.

  The GPS receiver 50 receives GPS signals from GPS satellites necessary for detecting the position of the vehicle. The autonomous navigation sensor 60 includes a gyro and the like for detecting the traveling direction of the vehicle, and a distance sensor that generates a pulse (vehicle speed pulse) at every constant travel distance.

  The main body 10 includes a control unit 102, a buffer memory 104, a map drawing unit 106, an operation screen / mark generation unit 108, a guidance route storage unit 110, a guidance route drawing unit 112, a traffic information drawing unit 114, a guidance unit 116, and an image composition unit. 118.

  The control unit 102 is configured by a CPU or the like and incorporates a memory 103. The control unit 102 controls the entire navigation device 100. Specifically, the control unit 102 calculates the position and speed of the vehicle based on the GPS signal received by the GPS receiving unit 50 and the output interval of the vehicle speed pulse from the autonomous navigation sensor 60, and the autonomous navigation sensor 60. The traveling direction of the vehicle detected by is acquired. Further, the control unit 102 instructs the HDD 20 to read the map data recorded on the hard disk 22. The map data read by the HDD 104 in response to an instruction from the control unit 102 is stored in the buffer memory 104.

  The map drawing unit 106 reads the map data stored in the buffer memory 104 and draws a map image corresponding to the screen of the display 70 based on the map data. At this time, the map drawing unit 106 uses the above-described point information in accordance with the operation of the operation unit 30 by the user and the operation state of the navigation device 100 as well as the planar display image of the map. An image can be drawn.

  Specifically, when drawing a map stereoscopic display image using the spot information shown in FIG. 3, the map drawing unit 106 performs predetermined processing based on the point coordinates and the stereoscopic display elevation value included in the spot information. A three-dimensional model of a map when a predetermined direction is viewed from the viewpoint position is generated, and processing for projecting the three-dimensional model onto the coordinate system of the screen of the display 70 that is two-dimensional is performed. On the other hand, when drawing the stereoscopic display image of the map using the spot information shown in FIG. 5, first, the control unit 102 determines the elevation value of the first spot and the elevation value of the second spot included in the spot information. Is calculated, and the elevation value for stereoscopic display at the first point is calculated according to the elevation value difference. Further, the map drawing unit 106 is a three-dimensional model of a map when a predetermined direction is viewed from a predetermined viewpoint position based on the point coordinates included in the point information and the elevation value for stereoscopic display calculated by the control unit 102. Is generated, and the three-dimensional model is projected onto a two-dimensional screen coordinate system.

  For the projection, known methods such as orthographic projection and perspective projection can be used. The predetermined viewpoint position is, for example, an upper position opposite to the traveling direction of the vehicle position, and is set based on the vehicle position and the traveling direction calculated by the control unit 102 described above. The predetermined direction is, for example, the traveling direction of the vehicle, and the traveling direction calculated by the control unit 102 described above is used.

  Further, the control unit 102 issues an image drawing instruction to the operation screen / mark generation unit 108 according to the operation of the operation unit 30 by the user or the operation state of the map display device 10. In response to this instruction, the operation screen / mark generation unit 108 draws various menu screens, a vehicle position mark, and an image of the cursor position.

  Further, the control unit 102 reads the map data stored in the buffer memory 104 in response to an operation of the operation unit 30 for searching for a guidance route by the user, and based on the map data, a predetermined route search algorithm, for example, Then, using a simulation calculation such as a horizontal search method or a Dijkstra method, a guide route having the lowest link cost from the starting point to the destination is searched. Information on the guide route is stored in the guide route storage unit 110.

  FIG. 6 is a diagram illustrating an example of guide route information. When a guide route that should pass through nodes of node numbers # 1, # 5, # 3, # 8, and # 7 in this order from the departure point to the destination is searched, as shown in FIG. In the information, node information on the guide route configured by associating the node numbers and node coordinates of these nodes is arranged in the order in which they should pass.

  Again, returning to FIG. The guide route drawing unit 112 generates a guide route image based on the guide route information stored in the guide route storage unit 110.

  In addition, the control unit 102 instructs the traffic information drawing unit 114 to select an image mode corresponding to the traffic information indicated by the VICS information received by the VICS receiving unit 40. The traffic information drawing unit 114 draws an image corresponding to the traffic information in a mode corresponding to this instruction.

  In addition, the control unit 102 instructs the guidance processing unit 114 to draw an image and generate a voice for guidance when the vehicle needs to turn at an intersection during route guidance based on the guidance route information. To do. The guidance processing unit 114 draws an enlarged image of an intersection and generates a guidance voice in response to an instruction from the control unit 102. The guidance voice is output from the speaker 80.

  Further, the control unit 102 instructs the image composition unit 118 to perform image composition in accordance with the operation of the operation unit 30 by the user and the operation state of the navigation device 100. In response to this instruction, the image synthesis unit 118 appropriately synthesizes various images drawn by the map drawing unit 106, the operation screen / mark generation unit 108, the guidance route drawing unit 112, the traffic information drawing unit 114, and the guide unit 116. Then, the obtained image is displayed on the display 70 as a display unit.

  In addition, the control unit 102 generates sound according to the operation of the operation unit 30 by the user and the operation state of the navigation device 100, and causes the speaker 80 to output the sound via the guide unit 116.

  In the present embodiment, the control unit 102 corresponds to a map data acquisition unit and a stereoscopic display elevation value setting unit, and the map drawing unit 106 and the image composition unit 118 correspond to a display processing unit.

  Next, details of the display of the stereoscopic display image of the map in the navigation device 100 will be described.

  First, a description will be given of a first embodiment which is a display of a stereoscopic display image of a map when the point information shown in FIG. 3 is included in the map data. FIG. 7 is a flowchart showing an operation of displaying a map stereoscopic display image in the first embodiment.

  The control unit 102 calculates the position and speed of the vehicle based on the GPS signal received by the GPS receiving unit 50 and the output interval of the vehicle speed pulse from the autonomous navigation sensor 60, and the vehicle detected by the autonomous navigation sensor 60. Is obtained (S101).

  Next, based on the calculated vehicle position, the control unit 102 draws a predetermined scale (for example, a scale set at that time) included in a predetermined range around the vehicle position based on the calculated vehicle position. Is instructed to read out map data corresponding to. The predetermined range is, for example, a rectangular area, specified by the longitude and latitude of the four corners, and the longitude and latitude of the four corners and the predetermined scale are output to the HDD 20 as a read instruction. In response to this instruction, the HDD 20 identifies and reads out map data of a predetermined scale of the leaf overlapping the predetermined range based on the input longitude and latitude of the four corners of the predetermined range from the hard disk 22 (S102). The read map data is stored in the buffer memory 104.

  Next, the control unit 102 determines whether or not a three-dimensional map display is instructed by the operation of the operation unit 30 by the user (S103). When the map display is not instructed, the control unit 102 outputs the vehicle position calculated in S101 to the map drawing unit 106 and instructs the map drawing unit 106 to draw a planar display image of the map. . In response to this instruction, the map drawing unit 106 reads the map data stored in the buffer memory 104 and, based on the map data, corresponds to the screen of the display 70 and displays a planar display image of the map centered on the vehicle position. Draw. The planar display image of the drawn map is output to the image composition unit 118. Further, the control unit 102 instructs the image composition unit 118 to perform image composition. In response to this instruction, the image compositing unit 118 draws a planar display image of the map from the map drawing unit 106, the operation screen / mark generation unit 108, the guidance route drawing unit 112, the traffic information drawing unit 114, and the guide unit 116. The obtained various images are appropriately combined, and the obtained image is displayed on the display 70 (S104).

  On the other hand, if it is determined in S103 that the map is displayed in three dimensions, the control unit 102 outputs the vehicle position calculated in S101 and the acquired traveling direction to the map drawing unit 106, and also displays the map. Is instructed to draw a stereoscopic display image. In response to this instruction, the map drawing unit 106 reads the map data stored in the buffer memory 104 and specifies the point coordinates and the elevation value for stereoscopic display included in the point information corresponding to each point included in the map data. (S105).

  Next, the map drawing unit 106 calculates, based on the vehicle position and the traveling direction from the control unit 102, an upper position opposite to the traveling direction of the vehicle position as a viewpoint position in the stereoscopic display of the map. Furthermore, the map drawing unit 106 shows a case where the traveling direction is viewed from the viewpoint position based on the point coordinates and the stereoscopic display altitude value corresponding to each point specified in S105 and the map image data included in the map image. A three-dimensional model of the map is generated, and the process of projecting the three-dimensional model onto a two-dimensional screen coordinate system is performed to draw a map stereoscopic display image corresponding to the screen of the display 70. The drawn map stereoscopic display image is output to the image composition unit 118. Further, the control unit 102 instructs the image composition unit 118 to perform image composition. In response to this instruction, the image composition unit 118 renders the map stereoscopic display image from the map drawing unit 106, the operation screen / mark generation unit 108, the guidance route drawing unit 112, the traffic information drawing unit 114, and the guide unit 116. The obtained various images are appropriately combined, and the obtained image is displayed on the display 70 (S106).

  Next, a second embodiment, which is a display of a stereoscopic display image of a map when the point information shown in FIG. 5 is included in the map data, will be described. FIG. 8 is a flowchart showing an operation of displaying a map stereoscopic display image in the second embodiment.

  The operations in S201 to S204 in FIG. 8 are the same as the operations in S101 to S104 in FIG. That is, the control unit 102 calculates the position and speed of the vehicle based on the GPS signal received by the GPS receiving unit 50 and the output interval of the vehicle speed pulse from the autonomous navigation sensor 60 and is detected by the autonomous navigation sensor 60. The traveling direction of the selected vehicle is acquired (S201).

  Next, based on the calculated vehicle position, the control unit 102 instructs the HDD 20 to read map data corresponding to a predetermined scale of map leaf included in the vehicle position and a predetermined range around it. In response to this instruction, the HDD 20 identifies map data of a predetermined scale that overlaps the predetermined range and reads it from the hard disk 22 (S202). The read map data is stored in the buffer memory 104.

  Next, the control unit 102 determines whether or not a stereoscopic display of the map is instructed by operating the operation unit 30 by the user (S203). When the map display is not instructed, the control unit 102 outputs the vehicle position calculated in S101 to the map drawing unit 106 and instructs the map drawing unit 106 to draw a planar display image of the map. . In response to this instruction, the map drawing unit 106 reads the map data stored in the buffer memory 104 and, based on the map data, corresponds to the screen of the display 70 and displays a planar display image of the map centered on the vehicle position. Draw. The planar display image of the drawn map is output to the image composition unit 118. Further, the control unit 102 instructs the image composition unit 118 to perform image composition. In response to this instruction, the image compositing unit 118 draws a planar display image of the map from the map drawing unit 106, the operation screen / mark generation unit 108, the guidance route drawing unit 112, the traffic information drawing unit 114, and the guide unit 116. The obtained various images are appropriately combined, and the obtained image is displayed on the display 70 (S204).

  On the other hand, in S203, when it is determined that the stereoscopic display of the map has been instructed, the control unit 102 operates the operation unit 30 by the user to perform the stereoscopic display using the stereoscopic display altitude value. It is determined whether or not the attribute is designated (S205).

  In the case where the attribute of the point to be stereoscopically displayed using the stereoscopic display elevation value is not designated, the stereoscopic display using the stereoscopic display elevation value is performed for all the points. That is, the control unit 102 reads the map data stored in the buffer memory 104, and for each point, the altitude value of that point (first point) based on the altitude value in the point information included in the map data. And elevation values of a plurality of points (second points) around the first point. For example, when the points are set as shown in FIG. 4, the second points are eight surrounding the first point. Next, the control part 102 calculates the average value of the altitude value of a some 2nd point. Further, the control unit 102 calculates a difference (elevation value difference) between the elevation value at the first point and the average value of the elevation values at the plurality of second points.

  Next, the control unit 102 compares the elevation value difference with the first predetermined value and the second predetermined value (wherein the second predetermined value <the first predetermined value). Then, when the elevation value difference is equal to or greater than the first predetermined value, the control unit 102 determines the stereoscopic display elevation value at the first point and the stereoscopic display elevation value at the second point from the elevation value difference. In other words, the elevation value for stereoscopic display of the first point is set so that the portion of the topography with a large undulation is made larger than the actual undulation. On the other hand, when the altitude value difference is equal to or smaller than the second predetermined value, the control unit 102 determines the stereoscopic display altitude value at the first point and the stereoscopic display altitude value at the second point from the altitude value difference. In other words, the elevation value for stereoscopic display at the first point is set so that the small undulation portion of the terrain is smaller than the actual undulation. In addition, when the difference in altitude value is larger than the second predetermined value and smaller than the first predetermined value, the control unit 102 uses the altitude value at the first point as it is for the stereoscopic display altitude at the first point. A value is set (S206).

  A filter is used to calculate the elevation value for stereoscopic display. FIG. 9A is an elevation value of a point, and FIG. 9B is a diagram showing a filter value. In FIG. 9A, the elevation value at the first point 201 is E, and the elevation values at the eight neighboring second points 202 are A, B, C, D, F, G, H, and I. . 9B, the filter value corresponding to the first point 201 is e, and the filter values corresponding to the eight neighboring second points 202 are a, b, c, d, f, g, h, i. These filter values are stored in the memory 103 in the control unit 102. In this case, the elevation value for stereoscopic display at the first point 201 is calculated by (aA + bB + cC + dD + eE + fF + gG + hH + iI) / (a + b + c + d + e + f + g + h + i). In addition, in order to calculate the elevation value for stereoscopic display, the elevation value and the filter value of which region are used are arbitrary, and as shown in FIG. 9, eight rectangles surrounding the first point 201 are surrounded. The altitude value and the filter value of the second point 202 in the area 212 are not limited. For example, an elevation value and a filter value at a point selected from the second points 202 of these eight rectangular regions 212 may be used, and an elevation value and a filter value at a point outside the eight rectangular regions 212 are used. May be.

  When setting the stereoscopic display elevation value at the first point so that the difference between the elevation value for stereoscopic display at the first point and the elevation value for stereoscopic display at the second point is larger than the difference in elevation value A high-pass filter is used. FIGS. 10A and 10B are diagrams illustrating examples of filter values of the high-pass filter. On the other hand, when the elevation value for stereoscopic display at the first point is set so that the difference between the elevation value for stereoscopic display at the first location and the elevation value for stereoscopic display at the second location is smaller than the elevation value difference. For this, a low-pass filter is used. FIGS. 11A and 11B are diagrams illustrating examples of filter values of the low-pass filter.

When the stereoscopic display altitude value of the thus each point is set, then the control unit 102, to the MAP drawing unit 106, for each point, for the point coordinates and three-dimensional display corresponding to the point In addition to outputting the altitude value, the vehicle position calculated in S201 and the acquired traveling direction are output to instruct to draw a three-dimensional display image of the map.

  In response to this instruction, the map drawing unit 106 calculates an upper position opposite to the traveling direction of the vehicle position as a viewpoint position in the stereoscopic display of the map based on the vehicle position and the traveling direction from the control unit 102. . Further, when the map drawing unit 106 sees the traveling direction from the viewpoint position based on the point coordinates and the stereoscopic display altitude value corresponding to each point from the control unit 102 and the map image data included in the map data. A three-dimensional model of the map is generated, and the three-dimensional model is projected onto a two-dimensional screen coordinate system. Thereby, a stereoscopic display image of the map corresponding to the screen of the display 70 is drawn. The drawn map stereoscopic display image is output to the image composition unit 118. Further, the control unit 102 instructs the image composition unit 118 to perform image composition. In response to this instruction, the image composition unit 118 renders the map stereoscopic display image from the map drawing unit 106, the operation screen / mark generation unit 108, the guidance route drawing unit 112, the traffic information drawing unit 114, and the guide unit 116. The obtained various images are appropriately combined, and the obtained image is displayed on the display 70 (S208).

  On the other hand, when it is determined in S205 that the attribute of the point where the stereoscopic display using the stereoscopic display elevation value is to be specified is specified, the control unit 102 reads the map data stored in the buffer memory 104 and includes the map data in the map data. The point information having the attribute designated by the user is specified. The point information specified here is point information corresponding to a point having an attribute designated by the user. Further, the control unit 102 specifies the elevation value in the point information corresponding to the point (first point) having the attribute specified by the specified user, and also the elevation value in the point information read from the buffer memory 104. Thus, the elevation values of a plurality of points (second points) around the first point are specified. Further, the control unit 102 calculates a difference (elevation value difference) between the elevation value at the first point and the average value of the elevation values at the plurality of second points.

  Thereafter, the same operation as that in S206 is performed. That is, the control unit 102 compares the altitude value difference with the first predetermined value and the second predetermined value. Then, when the elevation value difference is equal to or greater than the first predetermined value, the control unit 102 uses the high-pass filter to determine the stereoscopic display elevation value at the first point and the second point from the elevation value difference. The elevation value for stereoscopic display at the first point is set so that the difference from the elevation value for stereoscopic display becomes larger. On the other hand, when the elevation value difference is equal to or smaller than the second predetermined value, the control unit 102 uses the low-pass filter to determine the stereoscopic display elevation value at the first point and the second point from the elevation value difference. The elevation value for stereoscopic display at the first point is set so that the difference from the elevation value for stereoscopic display becomes smaller. In addition, when the difference in altitude value is larger than the second predetermined value and smaller than the first predetermined value, the control unit 102 uses the altitude value at the first point as it is for the stereoscopic display altitude at the first point. A value is set (S207).

  When the 3D display elevation value is set in this way, the control unit 102 next instructs the map drawing unit 106 for each point, the point coordinates corresponding to that point and the 3D display elevation value or elevation. And the vehicle position calculated in S201 and the acquired traveling direction are output to instruct to draw a three-dimensional display image of the map.

  In response to this instruction, the map drawing unit 106 calculates an upper position opposite to the traveling direction of the vehicle position as a viewpoint position in the stereoscopic display of the map based on the vehicle position and the traveling direction from the control unit 102. . Further, the map drawing unit 106 determines the traveling direction from the viewpoint position based on the point coordinates corresponding to each point from the control unit 102, the stereoscopic display elevation value or elevation value, and the map image data included in the map data. A three-dimensional model of the map when viewed is generated, a process of projecting the three-dimensional model onto the coordinate system of the two-dimensional screen is performed, and a stereoscopic display image of the map corresponding to the screen of the display 70 is drawn. . The drawn map stereoscopic display image is output to the image composition unit 118. Further, the control unit 102 instructs the image composition unit 118 to perform image composition. In response to this instruction, the image composition unit 118 renders the map stereoscopic display image from the map drawing unit 106, the operation screen / mark generation unit 108, the guidance route drawing unit 112, the traffic information drawing unit 114, and the guide unit 116. The obtained various images are appropriately combined, and the obtained image is displayed on the display 70 (S208).

  FIG. 12A is a diagram illustrating an example of a stereoscopic display image of a conventional map, and FIG. 12B is a diagram illustrating an example of a stereoscopic display image of a map according to the first and second examples. is there. FIG. 13A is a diagram showing an example of a cross section of the terrain in the conventional stereoscopic display image of the map, and FIG. 13B is a stereoscopic display image of the maps of the first and second embodiments. It is a figure which shows an example of the cross section of topography. Comparing FIG. 12 (a) and FIG. 13 (a) with FIG. 12 (b) and FIG. 13 (b), the topography 301 of the large undulation in FIG. 12 (a) and FIG. In 12 (b) and FIG. 13 (b), a larger undulation is obtained. On the other hand, the terrain 302 of the small undulation portion in FIGS. 12A and 13A becomes a smaller undulation in FIGS. 12B and 13B.

  As described above, in the case where the stereoscopic display is performed on the first point on the map, the navigation device 100 according to the present embodiment corresponds to the elevation value difference between the first point and the surrounding second point. The elevation value for the stereoscopic display of the first point is obtained so that the large undulation portion of the terrain is larger than the actual undulation, and the small undulation portion is smaller than the actual undulation, and the elevation value for the stereoscopic display is obtained. Based on this, a stereoscopic display image of the map is displayed. Therefore, it is possible to match the undulation state that the user grasps sensuously.

  In the above-described embodiment, the navigation device 100 as the map display device has been described. However, the present invention can be similarly applied to a map display device other than the navigation device 100.

  As described above, the map display device according to the present invention can match the three-dimensional display image of the map with the undulation state that the user grasps sensuously, and is useful as a map display device.

It is a figure which shows the structure of a map display apparatus. It is a figure which shows an example of road information. It is a figure which shows the 1st example of point information. It is a figure which shows an example of a point setting. It is a figure which shows the 2nd example of point information. It is a figure which shows an example of guidance route information. It is a flowchart which shows the operation | movement of the display of the map three-dimensional display image in 1st Example. It is a flowchart which shows the operation | movement of the display of the map three-dimensional display image in 2nd Example. It is a figure which shows the altitude value of a point, and the value of a filter. It is a figure which shows an example of the filter value of a high pass filter. It is a figure which shows an example of the filter value of a low-pass filter. It is a figure which shows an example of the conventional stereoscopic display image of a map, and an example of the stereoscopic display image of the map of 1st Example and 2nd Example. It is a figure which shows an example of the cross section of the topography in the stereoscopic display image of the conventional map, and the cross section of the topography of the stereoscopic display image of the map of 1st Example and 2nd Example.

Explanation of symbols

10 Main body 20 Hard disk drive (HDD)
DESCRIPTION OF SYMBOLS 22 Hard disk 30 Operation part 40 Communication part 50 GPS receiving part 60 Autonomous navigation sensor 70 Display 80 Speaker 100 Navigation apparatus 102 Control part 103 Memory 104 Buffer memory 106 Map drawing part 108 Operation screen and mark generation part 110 Guidance path memory | storage part 112 Guidance path Drawing unit 114 Traffic information drawing unit 116 Guide unit 118 Image composition unit

Claims (6)

A map display device that displays a three-dimensional map,
A virtual display in the three-dimensional display of the first point, which is determined according to the difference between the elevation value of the first point, which is each point on the map, and the elevation value of the second point around the first point. Map data acquisition means for acquiring map data including an elevation value for stereoscopic display indicating a correct elevation value;
A map display device comprising: a display processing unit configured to display a stereoscopic display image of a map including the first point on a display unit based on an elevation value for stereoscopic display of the first point included in the map data. A map display device that displays a three-dimensional map,
Map data acquisition means for acquiring map data including the elevation value of each point on the map;
The first data is determined according to a difference between an altitude value of a first point that is each point on the map and an altitude value of a second point around the first point, which is included in the map data. 3D display elevation value setting means for setting a 3D display elevation value indicating a virtual elevation value in the 3D display of the point;
A map display device comprising: a display processing unit configured to display a stereoscopic display image of a map including the first point on a display unit based on the elevation value for stereoscopic display of the first point.   The elevation value for stereoscopic display at the first point is the difference between the elevation values when the difference between the elevation value at the first point and the elevation value at the second point is equal to or greater than a first predetermined value. Is set such that the difference between the elevation value for stereoscopic display at the first point and the elevation value for stereoscopic display at the second point is larger than the elevation value at the first point and the second point. When the difference between the altitude value of the first point and the altitude value is equal to or smaller than a second predetermined value, the difference between the altitude value and the elevation value for stereoscopic display at the first point and the elevation value for stereoscopic display at the second point The map display device according to claim 1, wherein the map display device is set so that the difference is small.   The stereoscopic display altitude value setting means determines the stereoscopic display altitude value of the first point when display of a map stereoscopic display image based on the stereoscopic display altitude value is designated by operation of the operation unit. The map display device according to claim 2 to set. The map data includes an attribute of each point on the map,
The map display device according to claim 2 or 4, wherein, when the attribute is designated by an operation of an operation unit, the stereoscopic display altitude value setting unit sets the stereoscopic display altitude value of a spot having the attribute. . The elevation value for stereoscopic display at the first point depends on the difference between the elevation value at the first point and the elevation value determined from the elevation values at a plurality of second points around the first point. The map display device according to claim 1 or 2 defined as follows.

Images