JP4428712B2 - Navigation system, route search server, terminal device, and map display method - Google Patents

Description

  The present invention relates to a navigation system, a route search server, a terminal device, and a map display method for searching and guiding an optimum route from a departure place to a destination for pedestrians and automobile drivers. In particular, the present invention includes a polygon database in which roads are represented by polygons in order to display roads and guide routes in three dimensions, and a route search server creates guide route images based on polygon data and distributes them to a terminal device. The present invention relates to a navigation system, a route search server, a terminal device, and a map display method.

  Conventionally, when visiting a destination place on an unknown land, the user arrives while checking the transportation, road, landmark and address drawn on the map by using a map book or the like. In a car equipped with a car navigation system (hereinafter simply referred to as a car navigation system), a guidance displayed on a monitor screen or a voice output guidance (navigation) by starting the car navigation system and inputting a destination. Information) was reached.

  The car navigation system uses a GPS (Global Positioning System), receives GPS signals transmitted from a plurality of GPS satellites orbiting the earth with a GPS antenna, and transmits the GPS signals to the GPS signals. The position is specified by analyzing the satellite position and clock information included. At least four GPS satellites are required. The single positioning accuracy of GPS is generally over 10 m, but it is improved to 5 m or less by adopting DGPS (Differential GPS). In particular, GPS receivers that are currently installed only in some mobile phones are now being installed in all models of mobile phones called third generation.

  Various technologies have been proposed for using mobile terminals having such a positioning function. For example, a navigation device (car navigation) for automobiles has been developed, and map / route information is obtained using a mobile phone as a terminal. A communication navigation system for pedestrians distributed from an information distribution server (route search server) has been proposed.

  In recent years, the performance of mobile communication terminal devices such as mobile phones and PHS has been dramatically improved, and multi-functionalization has been progressing. In particular, the data communication function is strengthened in addition to the call function, and various data communication services are provided to the user via the Internet. A navigation service is one of them, and a communication navigation system that provides route guidance from a current position to a destination for not only a driver of a car but also a mobile phone user has been put into practical use.

  A general navigation device, a route search device and a route search method used in a communication navigation system are disclosed in, for example, the following Patent Document 1 (Japanese Patent Laid-Open No. 2001-165681). This navigation system is configured to send information on a departure point and a destination from a portable navigation terminal to an information distribution server, and the information distribution server searches and guides a route that matches a search condition from road network and traffic network data. Has been. As the search condition, there are means for moving from the departure place to the destination, for example, walking, automobile, combined use of railroad and walking, and the route is searched as one of the search conditions.

  The information distribution server has roads (routes) of map data as nodes and nodes as the positions of inflection points, links connecting the nodes as links, and cost information (distance and required time) of all links as a database. ing. Then, the information distribution server sequentially searches for a link from the departure node to the destination node with reference to the database, and traces the node and link with the smallest cost information of the link as a guide route. The shortest route can be guided to the portable navigation terminal. As such a route search method, a method called label determination method or Dijkstra method is used. Patent Document 1 also discloses a route search method using this Dijkstra method.

  By the way, a terminal device that has received a guidance route from an information distribution server such as a route search server is provided with a display means such as a liquid crystal display device, and displays a map and a guidance route on the display means as well as the current state of pedestrians and cars The position (current position of the terminal device) is displayed on the guidance route to guide pedestrians and cars to the destination. Generally, the map displayed on the display means is a plan view, that is, a display of a two-dimensional figure, but the building is simulated in order to make it easy to see the state of the plane bird's-eye view, landmarks and buildings with a sense of perspective. In particular, a method of displaying a bird's eye view expressed three-dimensionally and a method of displaying roads and buildings as a three-dimensional polygon image by the Z buffer method have been proposed.

  For example, the following Patent Document 2 (Japanese Patent Laid-Open No. 2001-27535) discloses a map display device that displays buildings and roads in three dimensions. In the map display device disclosed in Patent Document 2, when a three-dimensional map is displayed, the route guide line is shaded on the road and displayed three-dimensionally. When the route guide line is in a positional relationship hidden in the building, the overlapping portion of the route guide line is displayed in a different color from the non-overlapping portion. In particular, the display color of the route guide line and the display color of the building are drawn on a VRAM (video RAM) by a semi-transparent method in which pixels are alternately set, and the relative positional relationship between the route guide line and the building is shown. It is clarified to improve the visibility of the route guide line.

  In order to perform the display as described above, in the map display device disclosed in Patent Document 2, building shape data and height information are stored in the map data, and three-dimensional intersections are also stored as road shape data. Has been. Based on this map data, a three-dimensional drawing of a three-dimensional intersection of a building or road is drawn on the drawing unit, and a desired image is drawn on the drawing unit when the vehicle travels and reaches a route guidance position. A predetermined voice is uttered to guide the user to the destination.

  Similarly, in the navigation device disclosed in the following Patent Document 3 (Japanese Patent Laid-Open No. 10-267680), a guide route near an intersection displaying a road in three dimensions is displayed with a height from the road surface. Furthermore, a shadow is added to display the height so that it can be easily understood. When one or both of the road and the other road is an elevated road, the height of the guide route is displayed so as to appear higher.

  If a building is displayed three-dimensionally as well as a map and a route, the road and route are hidden by the figure of the building. For this reason, intersections that should turn left and right are behind the building, making it difficult to see. In order to eliminate such inconveniences, for example, the following Patent Document 4 (Japanese Patent Laid-Open No. 2000-112343) discloses a “navigation stereoscopic display method” technology that makes the three-dimensional display of a building in front of an intersection transparent. It is disclosed.

  In the three-dimensional display method for navigation disclosed in Patent Document 4, when a building is three-dimensionally displayed, it is determined whether or not there is an intersection scheduled to turn left or right on the map on the screen. It is determined whether or not there is a three-dimensionally displayed building in front of the intersection on the side to bend. In some cases, the building is stereoscopically displayed in a frame, and the inside of the building is transparently colored such as transparent red, and the other buildings are distinguished by performing normal stereoscopic display or simple wire frame display. This avoids the inconvenience that roads and routes are hidden by the figure of the building.

  Further, in the following Patent Document 5 (Japanese Patent Laid-Open No. 10-232605), a route in which altitude information (altitude) is added to a node (intersection, inflection point, etc.) constituting road data together with position information (latitude / longitude). A map database for search is provided, and three-dimensional road drawing information (image data) and guide route drawing information (image data) are calculated and generated based on map data (position and altitude information) of the searched guide route. An intersection road guidance display device configured to stereoscopically display roads, roads, and guidance routes is disclosed.

  Further, a map display device that has a two-dimensional display mode and a three-dimensional display mode and is configured so that a user can select one of the display modes or automatically switch according to a predetermined condition is also disclosed in, for example, the following patents: It is disclosed in Document 6 (Japanese Patent Laid-Open No. 2004-151752) and Patent Document 7 (Japanese Patent Laid-Open No. 11-24556).

  The electronic map display device disclosed in Patent Literature 6 senses a map information storage unit that stores map information of a plurality of display formats, a display unit, a display screen of the display unit, or an inclination angle of the electronic map display device. The control unit is configured to read out and display map information of a corresponding display format from the map information storage unit based on the detected tilt angle.

  In addition, the map display device disclosed in Patent Document 7 takes into account the height of a plurality of points in the plane map, the bird's-eye view map obtained by converting the plane map into a display format using the bird's-eye view method, and the ground surface of the bird's-eye view map. In a map display device that selectively displays a three-dimensional bird's-eye view map and a house map, (a) when a planar map is displayed, the display is switched to either the bird's-eye view map or the house map, (B) When the bird's-eye view map is displayed, the display is switched to either the stereoscopic bird's-eye view map or the planar map. (C) When the stereoscopic bird's-eye view map is displayed, either the bird's-eye view map or the planar map is displayed. The display is switched, and (d) when the house map is displayed, the display is switched to the plane map.

JP 2001-165681 A (FIGS. 1 and 2) JP 2001-27535 A (FIG. 1, FIG. 4, paragraph [0054]) JP-A-10-267680 (FIGS. 3 and 6) JP 2000-112343 A (FIGS. 14 and 15) Japanese Patent Laid-Open No. 10-232605 (FIGS. 4, 11, and 12) Japanese Patent Laying-Open No. 2004-151752 (FIG. 4) Japanese Patent Laid-Open No. 11-24556 (FIG. 23)

  In the navigation system, an optimum route from a desired departure point to a destination is searched based on map data, and a guidance route is specified. Then, the current position is measured by positioning means such as a GPS receiver, and when displaying a map or a guide route, the current position mark indicating the current position and the direction mark indicating the traveling direction are superimposed and displayed to the user. Inform location and direction of travel. In addition, guidance points such as intersections are set in the guide route data, and voice guidance data (for example, a voice message such as “This is a 300m intersection, please turn left”) is added as guidance at the guidance points. In this case, a voice message is reproduced and output through a speaker to guide the user.

  In general, a navigation device mounted on a vehicle and dedicated to search for a moving route for the vehicle has a high processing capacity of a processor and a large capacity of a storage device that accumulates map data and road data for route search. Therefore, the position and altitude information is stored in the map data as in Patent Document 5, and the road drawing information and the guidance route drawing for three-dimensional display are obtained by using the position and altitude information in the searched guidance route information. Information can be calculated and generated, and three-dimensional display can be performed.

  On the other hand, in a communication-type navigation system in which a mobile terminal device such as a mobile phone is used as a terminal device of the navigation system, the processing capacity of the processor constituting the terminal device is not as high as that of a vehicle-mounted navigation device. Controls not only the navigation function, but also the execution of other functions of the terminal device. For example, when a mobile phone is used as a terminal device, the processor is also used to execute a call function that is an original function of the mobile phone.

  For this reason, in a navigation system using a portable terminal device, in order to display a road and a guide route three-dimensionally by applying the method disclosed in Patent Document 5, the processor on the terminal device side is: It is necessary to calculate the three-dimensional drawing data of the road and the three-dimensional drawing data of the guidance route from the position and altitude information of the guidance route information distributed from the route search server. Further, when displaying on the display means of the terminal device, since the 3D image is displayed according to the height of the user's line of sight, the user's viewpoint is calculated when calculating the 3D drawing data of the road and the guide route. It is necessary to perform an operation according to the position (height of the line of sight).

  Therefore, there has been a problem that it is practically difficult to execute such an operation on a processor having a small processing capacity mounted in a terminal device such as a mobile phone. If such a calculation is executed on the terminal device side, there is a problem that the drawing speed is slow and processing of other functions of the terminal device is delayed.

Further, a route search server that receives a route search request from a terminal device and searches for a route to distribute a guide route to the terminal device also has the following problems. That is, the road network data required for the route search by the route search server only needs to be the position data of the link connecting the nodes, and does not require the altitude information of the nodes. The route search server needs to perform a plane (two-dimensional) route search as before, and also needs road network data (plane map data) having only position information. In addition to the plane map data, simultaneously providing road network data having altitude information as in Patent Document 5 has a problem in that it is a burden in search and data maintenance.

  Therefore, when displaying a three-dimensional road or a guide image, even if a route search is performed by a route search server having a processor with high calculation processing capability, the road network data is composed only of conventional position information and has altitude information. It is preferable to use a route that is not found. However, since the guide route information obtained as a result does not have height information as a matter of course, if the guide route drawing data used for drawing is generated as it is for the processing of the three-dimensional display, the height ( Elevation) is represented by 0.

  In addition to the road network data for search, the route search server includes a polygon database that stores polygon data for three-dimensional drawing of roads, and is configured to deliver road polygons corresponding to the guide route to the terminal device. However, there is a problem that the guide route image cannot be displayed on the road image displayed in three dimensions. That is, even if the terminal device displays a road three-dimensionally based on the polygons distributed from the route search server, the three-dimensional guide route drawing data cannot be calculated from the guide route information having no altitude information. A route image cannot be drawn on the road.

  FIG. 8 is a diagram schematically showing the above problem. As shown in FIG. 8, polygon data for three-dimensionally displaying a road RDRT corresponding to the guide route RT includes planes RD0 to RDN3... Having normal vectors according to the road inclination (direction of the road surface). When this is expressed by continuous polygon data and displayed on the display means, the road is three-dimensionally displayed according to the actual inclination as shown in FIG. However, since the guide route RT has no height, it is drawn on an image obtained by projecting the road RDRT onto a plane.

  That is, there is no difference in height when the polygonal surface of the road RDRT is horizontal, and the guide route image is displayed on the road image, but the continuous polygon (road) is a surface inclined upward, In such a portion where the surface continues continuously, the drawing data of the guide route is 0 height, so the guide route RT is drawn on the projection plane indicated by the dotted line in FIG. There is a problem that the guide route RT is displayed below the road image RDRT.

  In order for the terminal device to perform arithmetic processing for drawing the image of the guide route up to the surface of the 3D polygon (road polygon), there is a problem that the processing speed of the portable terminal device cannot provide a sufficient display speed. there were. This problem is particularly problematic in places where roads intersect three-dimensionally. This is because, even if a three-dimensionally intersecting road can be displayed three-dimensionally, it is unclear which road the guide route is on.

  The inventor of the present application has made various studies in order to solve the above-described problems. As a result, the route search server generates a guide route polygon on the display surface side of the polygon data, which is continuous surface data forming a road. As guide route data, it is distributed to the terminal device together with the polygon data of the road, and if this is displayed on the terminal device, the present invention is completed by conceiving that the road and the guide route can be displayed correctly in three dimensions. It is a thing.

  That is, the present invention has an object to solve the above-mentioned problems, and includes a database that stores road polygon data representing roads in polygons, and uses a route search server that can display roads in three dimensions, and guide routes A navigation system, a route search server, a terminal device, and a map display in which polygons are generated based on the road polygon data and distributed to the terminal device so that the terminal device can easily display roads and guide routes correctly in three dimensions. It is intended to provide a method.

In order to solve the above-mentioned problem, the invention according to claim 1 of the present application is
A route search server having a polygon database storing search network data for route search and road polygon data for three-dimensional display, and connected to the route search server via a network and distributed from the route search server A navigation system comprising a terminal device having display means for displaying a guidance route based on the guidance route data.
The route search server includes route search means, guidance route data creation means, and distribution data editing means. The route search means refers to search network data in response to a request from the terminal device. A planar two-dimensional guide route having no height information is searched, and the guide route data creating means refers to the road polygon stored in the polygon database, and the planar two-dimensional guide is placed on the road polygon. Based on the three-dimensional display guide route data obtained by projecting the route , a three-dimensional guide route polygon is created on the display surface of the three-dimensional display road polygon, and the distribution data editing means Deliver the route polygon to the terminal device,
The terminal device includes distribution data storage means for storing guide route data distributed from the route search server, three-dimensional display control means, two-dimensional display control means, and display mode control means. When the control means operates the three-dimensional display control means, the three-dimensional guide route polygon distributed from the route search server is displayed on the display means.

  The invention according to claim 2 of the present application is the invention according to claim 1, wherein the guide route data creating means generates the three-dimensional guide route data along data of continuous surfaces of the road polygon for three-dimensional display. It is characterized by creating.

  The invention according to claim 3 of the present application is the invention according to claim 2, wherein the guide route data creating means is configured to display the guide route polygon on the display surface side of the road polygon for three-dimensional display based on the three-dimensional guide route. It is characterized by creating.

  The invention according to claim 4 of the present application is the invention according to claim 1, wherein the terminal device displays the three-dimensional guide route polygon and the three-dimensional guide route polygon to which an offset value for offsetting the viewpoint position by a predetermined height is added. It is characterized by displaying on a means.

  The invention according to claim 5 of the present application is the invention according to claim 1, wherein the terminal device determines the direction of the line of sight based on the three-dimensional guide route and the guide route polygon received from the route search server. A guide route polygon is displayed on the display means.

  In the invention according to claim 6 of the present application, in the invention according to claim 1, when the terminal device performs two-dimensional display or bird's-eye view display, the height component is obtained from the data of the three-dimensional guide route received from the route search server. And the guide route is displayed on the display means.

The invention according to claim 7 of the present application is
Distribution data storage means for storing guide route data distributed from the route search server, three-dimensional display control means, two-dimensional display control means, display mode control means, and guide route data distributed from the route search server A route search server connected via a network to a terminal device having display means for displaying a guidance route based on
The route search server includes search network data for route search, a polygon database storing road polygon data for three-dimensional display, route search means, guidance route data creation means, distribution data edit means, The route search means searches for a planar two-dimensional guide route having no height information with reference to search network data in response to a request from the terminal device, and the guide route data creation means , Referring to the road polygon stored in the polygon database and projecting the planar two-dimensional guide route onto the road polygon , based on the data of the three-dimensional display guide route , create a 3D guide route polygon on the display surface of the road polygon, the distribution data editing means, said guide path polygon to the terminal device Characterized by trust.

  The invention according to claim 8 of the present application is the invention according to claim 7, wherein the guide route data creating means generates the three-dimensional guide route data along data of continuous surfaces of the road polygon for three-dimensional display. It is characterized by creating.

  The invention according to claim 9 of the present application is the invention according to claim 8, wherein the guide route data creating means is configured to provide the guide route polygon on the display surface side of the road polygon for three-dimensional display based on the three-dimensional guide route. It is characterized by creating.

  The invention according to claim 10 of the present application is the invention according to claim 7, wherein the guide route data creating means adds an offset value for offsetting the viewpoint position to a predetermined height based on the two-dimensional guide route. It is characterized by creating a three-dimensional guide route polygon and a three-dimensional guide route.

The invention according to claim 11 of the present application is
A route search comprising: search network data for route search; polygon database storing road polygon data for three-dimensional display; route search means; guidance route data creation means; and distribution data editing means. The means searches for a planar two-dimensional guide route having no height information by referring to the search network data in response to a request from the terminal device, and the guide route data creating means is stored in the polygon database. On the display surface of the road polygon for 3D display based on the data of the 3D display guide route obtained by referring to the road polygon and projecting the planar 2D guide route onto the road polygon. A three-dimensional guide route polygon is created, and the distribution data editing means sends a route search server that distributes the guide route polygon via a network. A terminal device connected Te,
The terminal device includes distribution data storage means for storing guide route data distributed from the route search server, three-dimensional display control means, two-dimensional display control means, display mode control means, and the route search server. Display means for displaying a guide route based on the guide route data distributed, and when the display mode control means operates the three-dimensional display control means, the three-dimensional information distributed from the route search server. The guide route polygon is displayed on the display means.

  The invention according to claim 12 of the present application is the invention according to claim 11, wherein the terminal device determines the direction of the line of sight based on the three-dimensional guide route and the guide route polygon received from the route search server. A guide route polygon is displayed on the display means.

  In the invention according to claim 13 of the present application, in the invention according to claim 11, when the terminal device performs two-dimensional display or bird's-eye view display, the height component is obtained from the data of the three-dimensional guide route received from the route search server. And the guide route is displayed on the display means.

The invention according to claim 14 of the present application is
A route search server having a polygon database storing search network data for route search and road polygon data for three-dimensional display, and connected to the route search server via a network and distributed from the route search server A map display method in a navigation system comprising a terminal device having display means for displaying a guide route based on guide route data,
The route search server includes route search means, guidance route data creation means, and distribution data editing means, and the route search means refers to search network data in response to a request from the terminal device. Searching for a planar two-dimensional guide route having no height information;
The guide route data creation means refers to road polygons stored in the polygon database, and based on data of a guide route for three-dimensional display obtained by projecting the planar two-dimensional guide route onto the road polygon. Generating a three-dimensional guide route polygon on the display surface of the road polygon for three-dimensional display ;
The delivery data editing means comprises delivering the guide route polygon to the terminal device;
The terminal device includes distribution data storage means for storing guide route data distributed from the route search server, three-dimensional display control means, two-dimensional display control means, and display mode control means,
When the display mode control means operates the three-dimensional display control means, the display mode control means includes a step of displaying the three-dimensional guide route polygon distributed from the route search server on the display means.

  The invention according to claim 15 of the present application is the invention according to claim 14, wherein the guide route data creating means creates a three-dimensional guide route on the road polygon by referring to the road polygon stored in the polygon database. Then, the step of creating a three-dimensional guide route polygon includes a process of creating the three-dimensional guide route data along data of continuous surfaces of the road polygon for three-dimensional display.

  The invention according to claim 16 of the present application is the invention according to claim 15, wherein the guide route data creating means creates a three-dimensional guide route on the road polygon by referring to the road polygon stored in the polygon database. Then, the step of creating the three-dimensional guide route polygon includes a process of creating the guide route polygon on the display surface side of the road polygon for three-dimensional display based on the three-dimensional guide route.

  The invention according to claim 17 of the present application is the invention according to claim 14, wherein the guide route data creating means creates a three-dimensional guide route on the road polygon by referring to the road polygon stored in the polygon database. Then, the step of creating a three-dimensional guide route polygon creates a three-dimensional guide route and a three-dimensional guide route polygon to which an offset value for offsetting the viewpoint position to a predetermined height is added based on the two-dimensional guide route. Including processing.

In the invention according to claim 1, the route search server includes search network data, a polygon database storing road polygon data for three-dimensional display, route search means, guidance route data creation means, and distribution data. Editing means, and the route search means searches for a planar two-dimensional guide route having no height information with reference to the search network data in response to a request from the terminal device, and guide route data creation means Refers to the road polygon stored in the polygon database and projects the planar two-dimensional guide route onto the road polygon , based on the data of the guide route for three-dimensional display obtained by the three-dimensional display guide A three-dimensional guide route polygon is created on the road polygon display surface and distributed to the terminal device.

  According to such a configuration, three-dimensional guide route data, guide route polygons using road polygon data for three-dimensional display without providing three-dimensional route search network data having route search server altitude information. Is generated and distributed to the terminal device, the terminal device can display a three-dimensional map without any arithmetic processing using the three-dimensional guide route data and the guide route polygon distributed from the route search server. It becomes like this.

In the invention according to claim 2, in the invention of claim 1, the guide route data creating means creates the three-dimensional guide route data along data of continuous surfaces of the road polygon for three-dimensional display.
According to such a configuration, it is possible to correctly create guide route data for three-dimensional display on a corresponding road even if the road intersects three-dimensionally.

In the invention according to claim 3, in the invention according to claim 2, the guide route data creating means places the guide route polygon on the display surface side of the road polygon for three-dimensional display based on the three-dimensional guide route. create.
According to such a configuration, a guide route polygon for three-dimensional display can be correctly created on a corresponding road even if the road intersects three-dimensionally.

In the invention according to claim 4, in the invention according to claim 1, the terminal device provides a three-dimensional guide route and a three-dimensional guide route polygon to which the offset value for offsetting the viewpoint position to a predetermined height is added to the display means. indicate.
According to such a configuration, the guide route can be three-dimensionally displayed by offsetting the height of the viewpoint, and a display that is easy to visually recognize can be achieved.

In the invention according to claim 5, in the invention according to claim 1, the terminal device determines the direction of the line of sight based on the three-dimensional guide route and the guide route polygon received from the route search server, and the guide route The polygon is displayed on the display means.
According to such a configuration, even when a road with a steep slope is three-dimensionally displayed, a road within a required viewing angle can be displayed, and a display that is easy to visually recognize can be displayed.

In the invention according to claim 6, in the invention according to claim 1, the terminal device removes a height component from the data of the three-dimensional guide route received from the route search server when performing the two-dimensional display or the bird's-eye view display. Then, the guide route is displayed on the display means.
According to such a configuration, when the terminal device displays a two-dimensional map, the two-dimensional map is used by using the three-dimensional guide route data without requesting the route search server for a two-dimensional route again. Can be displayed.

  In the invention according to claims 7 to 10, it is possible to provide a route search server constituting the navigation system according to claims 1 to 4, respectively. Moreover, in the invention concerning Claim 11 thru | or 13, the terminal device which comprises the navigation system concerning Claim 1, Claim 5, Claim 6 can be provided now, respectively. Furthermore, in the invention according to claims 14 to 17, the map display method in the navigation system according to claims 1 to 4 can be provided, respectively.

  Hereinafter, specific examples of the present invention will be described in detail with reference to examples and drawings. In the following embodiments, a mobile phone is a terminal device, and a navigation system that can selectively use a display mode for displaying a map or the like in a two-dimensional display, a display mode for displaying a bird's-eye view, or a display mode for displaying a three-dimensional display. However, the present invention is not limited to such an embodiment, and the terminal device may be a mobile terminal such as an in-vehicle terminal device. In this specification, the term “terminal device” including a mobile terminal is generically referred to.

  FIG. 1 is a block diagram showing a configuration of a navigation system according to an embodiment of the present invention. As shown in FIG. 1, the navigation system 10 includes a terminal device 20 and a route search server 30 connected via a network 12 such as the Internet. The route search server 30 includes route search means 316, search network data 317, a map database 315 storing map data, and a polygon database 318 storing three-dimensional polygons of roads and buildings.

  If there is a route search request from the terminal device 20 including a route search condition such as the current position, destination, moving means (automobile, walking, transportation or combined use of walking and transportation), the search network data 317 is referred to. A plurality of guide routes are searched in order of the shortest guide route or route length that matches the route search condition. Guide route data obtained as a result of the search is obtained from a plurality of unit map data (map data divided into areas of a predetermined size by latitude and longitude) including the current position selected from the map database 315 and from the polygon database 318. The data is distributed to the terminal device 20 together with the three-dimensional polygon data of the roads and buildings on the selected unit map data.

  The search network data 317 includes road network data 317A and traffic network data 317B, and can search for routes using walking, automobiles, or transportation. The road network data 317A and the traffic network data 317B are network data based on a normal plane map having no node altitude information. Therefore, the guidance route data searched by the route search means 316 is planar route data and does not have altitude information.

  In the present invention, since the route search server 30 displays the guide route without the altitude information searched by the route search means 316 as a three-dimensional guide route, the three-dimensional polygon of the road stored in the polygon database 318 is used. A guide route polygon is generated on the display surface side of the road polygon data by a procedure described later, and distributed to the terminal device 20 as guide route data. When the terminal device 20 displays a road or a guide route in a three-dimensional manner, a three-dimensional map display can be easily performed by displaying the road polygon and the guide route polygon distributed from the route search server 30 on the display means. Will be able to.

  The route search server 30 also includes a control unit 311, a communication unit 312, a distribution data editing unit 313, and a guide route data creating unit 314. Although not shown, the control unit 311 is a microprocessor having a RAM, a ROM, and a processor, and controls the operation of each unit by a control program stored in the ROM. The communication unit 312 is an interface for communicating with the terminal device 20 via the network 12. The guide route data creation means 314 creates guide route data, map data, guidance points, guidance data at guidance points, and the like searched as described above, and the distribution data editing means 313 stores the data such as the guide routes. Edit the data to be distributed to the device 20.

  When the terminal device 20 requests display of a three-dimensional map, the guide route data creation unit 314 uses road three-dimensional polygons stored in the polygon database 318 as described above to use road polygon data. A guide route polygon is generated on the display surface side and is output to the distribution data editing means 313 together with the road polygon as guide route data. At this time, if 3D polygons of buildings are accumulated in the polygon database 318, polygons of buildings around the road, which are guide routes, are also distributed to the terminal device 20, and the roads, guide routes, and surrounding buildings are displayed in 3D. Enable display.

  The road network data 317A is configured as follows. For example, when the road is composed of roads A, B, and C as shown in FIG. 6, the end points, intersections, and bending points of the roads A, B, and C are used as nodes, and the roads connecting the nodes are directed links. Link cost data with node data (node latitude / longitude), link data (link number) and link cost of each link (link distance or time required to travel the link) as data Composed.

  That is, in FIG. 6, Nn (◯ mark) and Nm (◎ mark) indicate nodes, and Nm (◎ mark) indicates a road intersection. Directional links connecting the nodes are indicated by arrow lines (solid line, dotted line, two-dot chain line). As for the links, there are links facing in the upward and downward directions of the road, but in FIG. 6, only the links in the direction of the arrows are shown for the sake of simplicity.

  When route search is performed using such road network data as a route search database, links linked from the starting node to the destination node are traced to accumulate the link cost, thereby minimizing the accumulated link cost. Search and guide the route. That is, in FIG. 6, when a route search is performed with the departure point as the node AX and the destination as the node CY, the road travels from the node AX to the road A, turns right at the second intersection, enters the road C, and reaches the node CY. The link cost is accumulated sequentially, and a route that minimizes the accumulated link cost is searched for and guided.

  Although other routes from the node AX to the node CY are not shown in FIG. 6, there are actually other such routes, so that a plurality of routes that can be reached from the node AX to the node CY are displayed. A search is performed in the same manner, and a route with the lowest link cost is determined as the optimum route. This method is performed by, for example, a known method called the Dijkstra method.

  On the other hand, the traffic network data 317B for route search of the transportation system is configured as follows. For example, as shown in FIG. 7, in the case of traffic routes A, B, and C, each station (each airport on an aircraft route) provided on each traffic route A, B, and C is used as a node, and the nodes are connected. A section is represented by a directional link, and node data (latitude / longitude) and link data (link number) are network data. In FIG. 7, Nn (◯ mark) and Nm (◎ mark) indicate nodes, Nm (◎ mark) indicates a transit point (such as a transfer station) on a traffic route, and a directional link connecting each node. It is indicated by an arrow line (solid line, dotted line, two-dot chain line). As links, there are links facing in the upward and downward directions of the traffic route. In FIG. 7, only the links in the direction of the arrows are shown for the sake of simplicity.

  However, the traffic network basically has a different link cost compared to the road network. In other words, in the road network, the link cost is fixed and static. However, in the traffic network, as shown in FIG. 7, trains and airplanes (hereinafter referred to as individual trains and airplanes) that operate traffic routes are used. A plurality of means of transportation). The time of departure from one node and the time of arrival at the next node are determined for each means of transportation (specified by timetable data and operation data), and individual routes do not necessarily link to adjacent nodes. There is a case. This is the case, for example, with express trains and trains that stop at each station. In such a case, a plurality of different links exist on the same traffic route, and the required time between nodes may differ depending on the transportation means.

  In the transportation network illustrated in FIG. 7, a plurality of transportation means (routes) Aa to Ac... Exist on the same link of the transportation route A, and a plurality of transportation means (routes) Ca to Cc. Will do. Therefore, unlike a simple road network, the transportation network of a transportation facility has a data amount proportional to the total number of transportation means (routes such as individual aircraft and trains). For this reason, the data of the traffic network becomes a huge amount of data compared to the data amount of the road network. Accordingly, much time is required for route search accordingly.

  In order to search for a route from a certain departure point to a certain destination using such traffic network data, all the means of transportation that can be used (ride) when arriving from the departure point to the destination are searched. It is necessary to specify the means of transportation that matches the search conditions.

  For example, in FIG. 7, when performing a route search with the departure point as a node AX of the traffic route A and specifying a certain departure time and using the node CY of the traffic route C as the destination, the route operates on the traffic route A. Of the transportation means Aa to Ac..., All transportation means after the departure time are sequentially selected as the departure route. Based on the arrival time at the transit node on the transit route C, among all the transit means Ca to Cc... Operating on the transit route C, all combinations of transit means after the time that can be boarded at the transit node. The total time required for each route, the number of transfers, and the like are guided.

  On the other hand, the terminal device 20 is a mobile phone equipped with a GPS positioning unit 212 such as a GPS receiver, for example, and includes a control unit 211, a GPS positioning unit 212, a display mode control unit 213, a bird's eye view display control unit 214, and a two-dimensional display. A control unit 215, a three-dimensional display control unit 216, a communication unit 217, a distribution request editing unit 218, a distribution data storage unit 219, a VRAM 220, a display unit 221, an operation / input unit 222, and the like are configured. Users can select walking or transportation as a means of transportation and receive route guidance using walking or transportation, and when they are in the passenger seat of a car, they can select a car as the means of transportation and get directions. Can receive.

  Although not shown, the control unit 211 includes a microprocessor (CPU) having a RAM and a ROM, and controls the operation of each unit by a control program stored in the ROM. The operation / input means 222 is for operation / input means consisting of numeric keys, alphabet keys, other function keys, selection keys, scroll keys, and the like. From the menu screen displayed on the display means 221 as output means Various input operations are performed by selecting a desired menu or operating keys. Accordingly, the display unit 221 also functions as a part of the operation / input unit 222. The communication unit 217 is an interface for communicating with the route search server 30 via the network 12.

  When a user wants to request a route search from the route search server 30, the user operates the operation / input unit 222 on the terminal device 20, selects a route search from the service menu displayed on the display unit 221, Enter route search conditions such as location, means of transportation (car, walking, transportation, or a combination of walking and transportation). The route search condition is edited into a distribution request to the route search server 30 by the distribution request editing unit 218 and transmitted to the route search server 30 via the communication unit 217.

  Distribution data from the route search server 30 is temporarily stored in the distribution data storage unit 219, read out from the distribution data storage unit 219 as necessary, and displayed on the display unit 221. The terminal device 20 has a first display mode (hereinafter referred to as a two-dimensional display mode) for two-dimensionally displaying a map, a guide route, a building image, and the like included in the distribution data, and a second three-dimensionally displayed for three-dimensional display. A display mode (hereinafter referred to as a 3D display mode) and a third display mode (hereinafter referred to as a bird's eye view display mode) for displaying a bird's eye view of a road or a building from a viewpoint position set at a predetermined altitude; The display mode control unit 213 selectively operates one of the bird's eye view display control unit 214, the two-dimensional display control unit 215, and the three-dimensional display control unit 216 to perform display on the display unit 221. The user designates a desired display mode using the operation / input means 222.

  The two-dimensional display control means 215 performs control to display them as a two-dimensional image (planar image) using plane data such as maps, roads, guide routes, and buildings distributed from the route search server 30, and performs three-dimensional display. The control means 215 performs control to process and display a three-dimensional image using the map, road, guide route, and building three-dimensional polygon data distributed from the route search server 30. The bird's eye view display control means 214 performs control for creating and displaying a bird's eye view image viewed from a viewpoint position at a predetermined altitude. The image data created by the bird's eye view display control unit 214, the two-dimensional display control unit 215, and the three-dimensional display control unit 216 is developed in dot units in the VRAM 220 as a drawing unit, and an image in a desired display mode is displayed on the display unit 221. Is displayed.

  The GPS positioning means 212 periodically measures the current position of the terminal device 20 and acquires the current position (latitude / longitude). A current position mark indicating the current position measured by the GPS positioning means 212 is displayed superimposed on an image such as a map or a guide route displayed on the display means 221.

  Next, a guide route polygon generation method according to the present invention will be described. Prior to that, a road three-dimensional polygon used for generating a guide route polygon will be described. When the road RD1 is viewed three-dimensionally, the road is composed of a continuous body having different slopes. That is, as shown in FIG. 2, the road RD1 becomes a surface (a) to a surface (d) having different inclinations. The three-dimensional polygon of the road includes the shape data of the continuous surfaces (a) to (d), the position data (position coordinates) of each vertex, and a normal vector (in FIG. 2) indicating the direction of each surface. Each arrow). Therefore, if surface image data is generated according to the surface shape data and each surface is arranged along the direction calculated based on the normal vector, a stereoscopic image of the road as shown in FIG. 2 can be displayed. Can do.

  Here, the orientation of each surface can be calculated by arranging the coordinates of each vertex of the surface according to a certain rule, even if the normal vector is not included in the polygon data. For example, if the rules are such that the respective coordinate points are arranged counterclockwise when viewed from the front side, the orientation of the surface can be calculated without having a normal vector.

  The same applies to the three-dimensional polygons of buildings. The building is broken down into its constituent faces, and each shape data, position data (position coordinates) of each vertex, and a normal vector indicating the orientation of each face It can be expressed by the normal vector which direction each face of the building is facing. Using such polygons, image data is generated by performing hidden surface processing by a well-known Z buffer method. Hidden surface processing refers to processing for erasing a surface that is not visible from the direction of the line of sight, thereby displaying a three-dimensional image of the building.

  For example, a building polygon is made up of graphic data of surfaces constituting the building as shown in FIG. In FIG. 3, building A is composed of graphic data of surfaces such as surfaces SA1, SA2, and SA3, and has a normal vector indicating the direction of each surface. For example, the surface SA1 of the building A has a normal vector A1. Further, in FIG. 3, the back side surface of the building is not visible, but polygon data of the back side surfaces SA4, SA5, and SA6 are prepared in the same manner. For example, the surface on the back side of the surface SA1 is the surface SA4, and has a normal vector A4 that is opposite to the normal vector A1 of the surface SA1.

  The same applies to the building B, which is composed of graphic data of the surfaces SB1 to SB6 and has a normal vector indicating the direction of each surface. When such a polygonal figure is viewed from the viewpoint position P of FIG. 3 on the surface of each building, the surface in which the surface is visible from the viewpoint position from the vector that anticipates the surface of interest from the viewpoint position and the normal vector of the surface Whether or not and the direction the surface is facing can be known.

  For example, assuming that the surface of interest from the viewpoint position P is the surface SA1 of the building A, a vector VA1 that looks into the surface SA1 from the viewpoint position P is taken. If the angle θA1 formed by the vector VA1 and the normal vector A1 (the inner product of both vectors is less than a right angle) is less than a right angle, it can be seen that the surface of this surface faces the viewing direction. Therefore, it can be seen that this surface is a surface displayed on the display means. If the angle formed by both vectors is not less than a right angle, such as the vector VB1 and the normal vector B1, it can be seen that the surface is not visible from the viewpoint position, and this surface is not displayed on the display means. In FIG. 3, E is the height of the viewpoint position.

  On the other hand, the guide route data searched by the route search means 316 is composed of nodes having only position information (latitude / longitude) having no altitude information and link data connecting the nodes. Even if this is drawn along the road shape of the map, since the image has an altitude of 0, it becomes only a planar image as shown in FIG. Therefore, in the present invention, the guide route polygon is generated on the display surface side of the road polygon using the data of the road polygon corresponding to the guide route.

[Create guide route for 3D display]
FIG. 4 is a schematic diagram showing this procedure, and a guide route is generated on the road polygon RDRT corresponding to the guide route RT. The route search server 30 (guide route data creation means 314) projects the guide route RT as a route search result onto the road polygon data RDRT for three-dimensional display corresponding to the guide route RT, and displays the top of the polygon. A guide route for three-dimensional display is created.

  At this time, when a plurality of road polygons RDCPG for 3D display overlap at the beginning (starting point) of the 3D guide route, a 3D guide route is created with reference to the uppermost polygon. And according to a route search result, a guide route is extended on the surface of a continuous road polygon.

  If a three-dimensional guide route cannot be drawn on the continuous road polygon plane at this time, it indicates that the road polygon at the beginning of writing is an error. In this case, the process returns to the beginning, and a three-dimensional guide route is drawn from the underlying road polygon. Even in the determination of the three-dimensional guide route ahead, even if there is a three-dimensional intersection in the middle if the three-dimensional guide route is drawn while following the connection of road polygon data (continuous surfaces) for three-dimensional display. There is no mistake in the route.

  That is, in FIG. 4, when the guide route RT is a route passing through the road RDRT passing over the three-dimensional intersection, even if the road RDC is assumed to be on and the guide route polygon is started to be created on the road polygon of the road RDC, If you follow a continuous surface of an RDC road polygon, you will not be able to draw a guide route on one of the continuous surfaces. According to the method of following a continuous surface as described above, Guide routes can be created.

[Create a guide route polygon]
Next, the guide route data creating means 314 creates a guide route polygon for 3D display based on the 3D display guide route data created as described above. When a three-dimensional guide route is obtained as described above, a guide route polygon RTPG (see FIG. 4) is created on the surface of the three-dimensional display road polygon RDPG referred to at that time.

  Here, if the guide route polygon RTPG is included in the same plane as the road polygon for 3D display, it is not determined which plane is visible when the terminal device 20 performs 3D display using the Z buffer method or the like. Therefore, the guide route polygon is created slightly apart in the surface direction (normal vector) of the road polygon for 3D display. At this time, it is sufficient to keep the minimum effective number that can be processed by the three-dimensional display control means 216 of the terminal device 20, and for example, about 0.1 m. On the display means 221, the three-dimensional display road polygon appears to be exactly overlapped, so that the user will not be mistaken as if the guide route polygon is on another road.

  Note that this method can also be applied to displaying a route on the back surface of an elevated road, for example, when the elevated road is looked up from below, as processing unique to a polygon for three-dimensional display. If the link of the route search result has an attribute of elevated or three-dimensional intersection, in addition to the guide route polygon created on the road surface, the road is based on the downward 3D display road polygon. A guide route polygon may be created below the surface. In this way, the guidance route can be displayed even when the route is mistaken and route matching is lost and the viewpoint moves to another place, or when the viewpoint is moved manually, which is very easy to understand.

  When the terminal device 20 is operated by a pedestrian to display a map or a guide route, the viewpoint position is generally offset to the average eye height (about 1.5 m height) of the pedestrian. And display according to the height of the user's viewpoint. FIG. 5 is a schematic diagram showing this concept. As shown in FIG. 5, when the height of the pedestrian's eyes is set as the viewpoint position E and the height to the viewpoint is added as an offset value, and the road RD is displayed based on the three-dimensional road polygon, the inclination of the road is actually The displayed road can be viewed with the same feeling as when the road is viewed. In this case, on the route search server 30 side, a 3D display road polygon, guide route data, and guide route polygon are created by adding a standard pedestrian eye height of about 1.5 m as an offset in advance. It may be distributed to the device 20.

[Display on terminal device 20]
The terminal device 20 receives the three-dimensional display guide route, the guide route polygon, and the three-dimensional display road polygon generated as described above from the route search server 30 and displays the three-dimensional display of the road and the guide route. It can be carried out.

  At this time, for example, the default viewpoint may be a three-dimensional guide route, and the height of the viewpoint may be moved by a user operation on the terminal device 20 side. The standard direction of the line of sight is the vector direction of the three-dimensional guide route. This makes it possible to follow the direction of the line of sight even when encountering a steep slope. An image within a required viewing angle can be displayed. For example, if a road with a steep slope such as a stairs (pedestrian bridge) is displayed in the horizontal line-of-sight direction, the road image that has gone down the stairs and the road image that has gone up the stairs are displayed sufficiently. The display is unnatural.

  By aligning the direction of the line of sight with the vector direction of the three-dimensional guide route, it is possible to display a road image within a necessary viewing angle and display a natural road image. In any case, the terminal device 20 can perform quick three-dimensional display without worrying about overlapping roads and guide routes only by performing general three-dimensional display using the Z buffer method. Become.

  In addition, the terminal device 20 can select a display mode using the operation / input unit 222 to perform normal three-dimensional display or bird's-eye view display. In this case, it is not necessary to re-receive the two-dimensional guide route data from the route search server 30, and the guide route may be drawn on the plane map by ignoring the height data of the three-dimensional guide route data. I can do it.

  As described above in detail, according to the present invention, a database for storing road polygon data representing roads in polygons is provided, and a route search server that can display roads in three dimensions is used. In order to create 3D guide route data and guide route polygons using the road polygon data for distribution to the terminal device, the terminal device uses the 3D guide route data and guide route polygon distributed from the route search server. It is possible to display a three-dimensional map without any calculation processing. As a result, the terminal device can easily display the road and the guide route in three dimensions correctly.

It is a block diagram which shows the structure of the navigation system concerning the Example of this invention. It is a schematic diagram for demonstrating the structure of a road polygon. It is a schematic diagram for demonstrating the structure of a building polygon. It is a schematic diagram for demonstrating the production | generation procedure of the guidance route polygon concerning this invention. It is a schematic diagram which shows the concept of offsetting the height of a user's viewpoint and displaying in three dimensions. It is a schematic diagram which shows the concept of the road network data for a route search. It is a schematic diagram which shows the concept of the traffic network data for a route search. It is a schematic diagram which shows the relationship with the two-dimensional guidance route data at the time of carrying out the three-dimensional display of the road using three-dimensional polygon data.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 .... Navigation system 12 ... Network 20 ... Terminal device 211 ... Control means 212 ... GPS positioning means 213 ... Display mode control means 214 ... Bird's eye view display control means 215 ... 2D display control means 216 ... 3D display control means 217 ... Communication means 218 ... Distribution request editing means 219 ... Distribution data storage means 220 ... VRAM
221 ... Display means 222 ... Operation / input means 30 ... Route search server 311 ... Control means 312 ... Communication means 313 ... Distribution data editing means 314 ... Guide route data creation Means 315 ... Map database 316 ... Route search means 317 ... Search network data 317A ... Road network data 317B ... Traffic network data 318 ... Polygon database

Claims (17)

A route search server having a polygon database storing search network data for route search and road polygon data for three-dimensional display, and connected to the route search server via a network and distributed from the route search server A navigation system comprising a terminal device having display means for displaying a guidance route based on the guidance route data.
The route search server includes route search means, guidance route data creation means, and distribution data editing means. The route search means refers to search network data in response to a request from the terminal device. A planar two-dimensional guide route having no height information is searched, and the guide route data creating means refers to the road polygon stored in the polygon database, and the planar two-dimensional guide is placed on the road polygon. Based on the three-dimensional display guide route data obtained by projecting the route , a three-dimensional guide route polygon is created on the display surface of the three-dimensional display road polygon, and the distribution data editing means Deliver the route polygon to the terminal device,
The terminal device includes distribution data storage means for storing guide route data distributed from the route search server, three-dimensional display control means, two-dimensional display control means, and display mode control means. A navigation system configured to display a three-dimensional guide route polygon distributed from the route search server on the display unit when the control unit operates the three-dimensional display control unit.   2. The navigation system according to claim 1, wherein the guide route data creating means creates the three-dimensional guide route data along data of continuous surfaces of the road polygon for three-dimensional display.   The navigation system according to claim 2, wherein the guide route data creating means creates the guide route polygon on the display surface side of a road polygon for three-dimensional display based on the three-dimensional guide route.   The navigation system according to claim 1, wherein the terminal device displays a three-dimensional guide route polygon and a three-dimensional guide route polygon to which an offset value for offsetting the viewpoint position by a predetermined height is displayed on the display means. .   The terminal device determines the direction of the line of sight based on the three-dimensional guide route and the guide route polygon received from the route search server, and displays the guide route polygon on the display means. The navigation system described in.   The terminal device, when performing two-dimensional display or bird's-eye view display, removes a height component from the data of the three-dimensional guide route received from the route search server and displays the guide route on the display means. The navigation system according to claim 1. Distribution data storage means for storing guide route data distributed from the route search server, three-dimensional display control means, two-dimensional display control means, display mode control means, and guide route data distributed from the route search server A route search server connected via a network to a terminal device having display means for displaying a guidance route based on
The route search server includes search network data for route search, a polygon database storing road polygon data for three-dimensional display, route search means, guidance route data creation means, distribution data edit means, The route search means searches for a planar two-dimensional guide route having no height information with reference to search network data in response to a request from the terminal device, and the guide route data creation means , Referring to the road polygon stored in the polygon database and projecting the planar two-dimensional guide route onto the road polygon , based on the data of the three-dimensional display guide route , create a 3D guide route polygon on the display surface of the road polygon, the distribution data editing means, said guide path polygon to the terminal device The route search server characterized by Shin.   8. The route search server according to claim 7, wherein the guide route data creating means creates the three-dimensional guide route data along data of continuous surfaces of the road polygon for three-dimensional display.   9. The route search server according to claim 8, wherein the guide route data creating means creates the guide route polygon on the display surface side of a road polygon for three-dimensional display based on the three-dimensional guide route.   The guide route data creating means creates a three-dimensional guide route and a three-dimensional guide route polygon to which an offset value for offsetting a viewpoint position to a predetermined height is added based on the two-dimensional guide route. Item 8. The route search server according to Item 7. A route search comprising: search network data for route search; polygon database storing road polygon data for three-dimensional display; route search means; guidance route data creation means; and distribution data editing means. The means searches for a planar two-dimensional guide route having no height information by referring to the search network data in response to a request from the terminal device, and the guide route data creating means is stored in the polygon database. On the display surface of the road polygon for 3D display based on the data of the 3D display guide route obtained by referring to the road polygon and projecting the planar 2D guide route onto the road polygon. A three-dimensional guide route polygon is created, and the distribution data editing means sends a route search server that distributes the guide route polygon via a network. A terminal device connected Te,
The terminal device includes distribution data storage means for storing guide route data distributed from the route search server, three-dimensional display control means, two-dimensional display control means, display mode control means, and the route search server. Display means for displaying a guide route based on the guide route data distributed, and when the display mode control means operates the three-dimensional display control means, the three-dimensional information distributed from the route search server. The guide route polygon is displayed on the display means.   12. The terminal device according to claim 11, further comprising: determining a direction of a line of sight based on the three-dimensional guide route and the guide route polygon received from the route search server and displaying the guide route polygon on the display unit. The terminal device described in 1.   The terminal device, when performing two-dimensional display or bird's-eye view display, removes a height component from the data of the three-dimensional guide route received from the route search server and displays the guide route on the display means. The terminal device according to claim 11. A route search server having a polygon database storing search network data for route search and road polygon data for three-dimensional display, and connected to the route search server via a network and distributed from the route search server A map display method in a navigation system comprising a terminal device having display means for displaying a guide route based on guide route data,
The route search server includes route search means, guidance route data creation means, and distribution data editing means, and the route search means refers to search network data in response to a request from the terminal device. Searching for a planar two-dimensional guide route having no height information;
The guide route data creation means refers to road polygons stored in the polygon database, and based on data of a guide route for three-dimensional display obtained by projecting the planar two-dimensional guide route onto the road polygon. Generating a three-dimensional guide route polygon on the display surface of the road polygon for three-dimensional display ;
The delivery data editing means comprises delivering the guide route polygon to the terminal device;
The terminal device includes distribution data storage means for storing guide route data distributed from the route search server, three-dimensional display control means, two-dimensional display control means, and display mode control means,
A map display method comprising a step of displaying, on the display means, a three-dimensional guide route polygon distributed from the route search server when the display mode control means operates the three-dimensional display control means. .   The step of the guide route data creating means creating a three-dimensional guide route polygon by referring to the road polygon stored in the polygon database and creating a three-dimensional guide route on the road polygon is the three-dimensional display. The map display method according to claim 14, further comprising a process of creating the three-dimensional guide route data along data of continuous surfaces of road polygons.   The step of the guide route data creating means creating a 3D guide route polygon by referring to the road polygon stored in the polygon database and creating a 3D guide route on the road polygon includes the 3D guide 16. The map display method according to claim 15, further comprising a process of creating the guide route polygon on the display surface side of the road polygon for three-dimensional display based on the route.   The step of the guide route data creating means creating a three-dimensional guide route polygon by referring to the road polygon stored in the polygon database and creating a three-dimensional guide route polygon on the road polygon includes the two-dimensional guide. The map display method according to claim 14, further comprising a process of creating a three-dimensional guide route and a three-dimensional guide route polygon to which an offset value for offsetting the viewpoint position to a predetermined height is added based on the route.

Images