JP2006113013A - Digest map display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a digest map display device which can discriminate between a search route passing through a high-level road and a search route passing through a road under the high level road even when the amount for shifting the search route is small. <P>SOLUTION: When the search route 101 passing through the high-level road overlaps with the search route 102 passing through the road under the high-level, the search route 101 is moved parallel to the direction of an arrow 103 by the length half of the line width of the search route 101. The search route 102 is then moved parallel to the direction of an arrow 104 by the length half of the line width of the search route 102. A pipe 105 is displayed, in the state that it looks as if the search route 102 passed through the pipe 105. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an apparatus for displaying a summary map obtained by simplifying a road map.

  In order to make it easier to see the elevated road and the road below it in the deformed map creation means that deforms the map, the display position of the elevated road is moved in parallel so that it is between the elevated road and the road below it. 2. Description of the Related Art A traffic information display device that displays an elevated road and a road located therebelow by adding pier marks at regular intervals is known (Patent Document 1).

Japanese Patent Laid-Open No. 10-177338

  In the apparatus disclosed in Patent Document 1, in order to distinguish a road having an upper and lower positional relationship such as an elevated road and a road located thereunder, the position of one road displayed on the deformed map is shifted, There is a problem that the position of the pier mark must be shifted to such an extent that it can be displayed between the two roads, and the amount of shift becomes large.

(1) The summary map display device of the invention of claim 1 comprises search means for calculating a plurality of search routes, and summary map creation means for creating a summary map with a simplified road shape based on road map data. The summary map creating means is configured to select at least one elevated road and at least one road under the elevated road from the plurality of searched routes. A tubular mark is drawn so that it overlaps a part of the search route that passes through one road and part of the search route that passes through the other road, and the search route that passes through one road passes through the tubular mark. It is characterized by doing.
(2) According to the invention of claim 2, in the summary map display device according to claim 1, when the summary map creating means has a plurality of search routes passing through one road, the plurality of search routes are the tubular marks. It is displayed so that it may pass through.
(3) The invention of claim 3 is the summary map display device according to claim 1 or 2, wherein the road map data represents the shape of the road by the shape of a link set for each predetermined road section. The creating means creates a summary map on which a plurality of search routes are displayed by fixing the positions of both end points of the link and simplifying the shape of the link.
(4) According to the invention of claim 4, in the summary map display device according to claim 3, the summary map creating means selects one of the points preset on the link as a storage point, The positions of the both end points are fixed, and the shape of the link is simplified.
(5) The invention according to claim 5 is the summary map display device according to claim 3 or 4, wherein the point selection means for selecting any of points preset on the link and the point selection means are selected. Line segment setting means for setting a plurality of second line segments connecting the point and each of both end points in order, and each of the second line segments set by the line segment setting means is set in a predetermined direction. Direction correcting means for correcting the direction of each of the second line segments, and second direction whose direction has been corrected by the direction correcting means so that the angle formed with respect to the predetermined unit angle is an integral multiple of a predetermined angle. The intersection detection means for obtaining an intersection when each of the line segments is extended, the intersection detected by the intersection detection means, and either one of the two end points or the selected point is connected to the second point Length correction means for correcting the length of each line segment; The point selection means further selects a point farthest from the third line segment connecting each of the end points and the selected point among the points set in advance on the link to create a summary map The means creates a summary map in which a plurality of search routes are displayed by simplifying the shape of the link using each of the second line segments whose lengths are corrected by the length correction means. And

  According to the present invention, in a section where the search route passing through the elevated road and the search route passing through the elevated road are displayed in an overlapping manner, one of the search routes is displayed so as to pass through the tubular mark. Therefore, even if the amount of shift of the search route is small, it can be distinguished whether the search route passes through the elevated road or the search route passes through the road under the elevated road.

  A configuration of a navigation apparatus according to an embodiment of the present invention is shown in FIG. This navigation device is mounted on a vehicle, searches for multiple routes to a set destination, and simplifies the shape of the road based on the normal map for each route. Create and display a summarized map (hereinafter referred to as a summary map). Then, the user is allowed to select one of the displayed routes, and the vehicle is guided to the destination using the route as a recommended route. Although the summary map will be described in detail later, a map that performs direction quantization processing, curve approximation processing, and the like on the road shape data of the map data to represent the original road shape in a deformed manner is generically named.

  The navigation device 1 shown in FIG. 1 includes a control circuit 11, a ROM 12, a RAM 13, a current location detection device 14, an image memory 15, a display monitor 16, an input device 17, and a disk drive 18. The disc drive 18 is loaded with a DVD-ROM 19 in which map data is recorded.

  The control circuit 11 includes a microprocessor and its peripheral circuits, and performs various processes and controls by executing a control program stored in the ROM 12 using the RAM 13 as a work area. By executing processing as will be described later in the control circuit 11, a plurality of routes are searched for the set destination based on the map data recorded on the DVD-ROM 19, and the whole of each route is searched. A summary map is created and displayed on the display monitor 16 respectively.

  The current location detection device 14 is a device that detects the current location of the host vehicle. For example, a vibration gyro 14a that detects the traveling direction of the host vehicle, a vehicle speed sensor 14b that detects a vehicle speed, and a GPS sensor that detects a GPS signal from a GPS satellite. 14c and the like. The navigation device 1 can determine a route search start point when searching for a recommended route based on the current location of the host vehicle detected by the current location detection device 14.

  The image memory 15 temporarily stores image data to be displayed on the display monitor 16. This image data includes road map drawing data for displaying a summary map image, various graphic data, and the like, and is created by the control circuit 11 based on the map data recorded on the DVD-ROM 19. Using the image data stored in the image memory 15, a summary map of the entire route is displayed on the display monitor 16.

  The input device 17 has various input switches for the user to set a destination and the like, which is realized by an operation panel, a remote controller, or the like. The user operates the input device 17 according to a screen instruction displayed on the display monitor 16 to set a destination by designating a place name or a position on the map, and to search the navigation apparatus 1 for a route search to the destination. Can be started.

  The disk drive 18 reads map data used to create a summary map from the loaded DVD-ROM 19. Although an example using a DVD-ROM is described here, the map data may be read from a recording medium other than the DVD-ROM, such as a CD-ROM or a hard disk. The map data includes a route calculation data used for calculating a plurality of routes, an intersection name, a road name, road altitude information, and the like to guide the host vehicle to the destination according to a recommended route selected by the user. Include route guidance data, road data representing roads, and background data representing map shapes other than roads such as coastlines, rivers, railways, and various facilities (landmarks) on maps.

  In the road data, the smallest unit representing a road section is called a link. That is, each road is composed of a plurality of links set for each predetermined road section. In addition, the length of the road section set by a link differs, and the length of a link is not constant. A point connecting the links is called a node, and each node has position information (coordinate information). Also, a point called a shape interpolation point may be set between nodes in the link. Each shape interpolation point also has position information (coordinate information) like each node. The link shape, that is, the shape of the road is determined based on the position information of the node and the shape interpolation point. In the route calculation data, a value called a link cost for representing the time required for passing the vehicle is set corresponding to each of the links.

  As described above, when a route search process is selected by a user operation on the input device 17, a route search program is executed in the control circuit 11. This program processing will be described with reference to the flowchart shown in FIG. In this route search process, the route calculation to the set destination is performed by a predetermined algorithm based on the route calculation data using the current location detected by the current location detection device 14 as a route search start point, and a plurality of destinations are calculated. Is required. Then, a summary map of the entire route obtained in this way is created based on the road data and displayed on the display monitor 16.

  In step S100, the route search destination is set according to the destination input by the user. In step S200, a plurality of routes are searched from the current location of the host vehicle, which is a route search start point, to the destination set in step S100. At this time, as described above, the route calculation is performed by a predetermined algorithm based on the route calculation data. Note that the current location of the host vehicle is obtained by the current location detection device 14 at regular intervals.

  In step S200, a route search is performed according to various route search conditions in order to search for a plurality of routes. For example, a route search is performed according to route search conditions such as toll road priority, general road priority, and distance priority, and a plurality of routes are searched by obtaining an optimum route under each condition. Alternatively, a plurality of routes may be searched by searching for routes other than the optimum route under one route search condition. For example, by obtaining a route search result including a route having the smallest total link cost to a destination as an optimum route and further including a route having a difference between the optimum route and the sum of link costs within a predetermined value. A plurality of routes can be searched under the route search condition.

  In step S300, coastline extraction processing is executed. Here, as preprocessing necessary for executing the coastline drawing process in step S800, the shape of the coastline within a predetermined range is extracted from each route searched in step S200. The coastline extraction process may be executed as necessary, and may not be executed. In the present invention, since the processing contents here are not directly related, detailed description thereof is omitted.

  In step S400, a link simplification process is executed. Here, as a pre-process for enabling the process to be executed correctly in the summary map creation process in step S500, a process for simplifying the link of each route searched in step S200 is performed. Specifically, a process of integrating adjacent parts of a plurality of links and expressing them as one link (proximity link integration process), a process of removing a minute link (minute link removal process), A process of removing a shape interpolation point having a minute interval between the points (a minute interval intermediate point removing process) is executed for each path. The link simplification process may be executed as necessary, and may not be executed. In the present invention, since the processing contents here are not directly related, detailed description thereof is omitted.

  In step S500, a summary map creation process is executed for each route searched in step S200 and further subjected to the link simplification process in step S400 as necessary. By this summary map creation process, a summary map representing the entire route, that is, the current location to the destination is created. The processing content at this time will be described in detail later.

  In step S600, a scale change process is executed. Here, a process of partially changing the scale of the summary map created in step S500 is performed. For example, the scale around the starting point and the destination is made larger than the other parts so that the surroundings of the starting point and the destination are enlarged so that it can be easily seen. Note that the scale changing process may be executed as necessary, and may not be executed. In the present invention, since the processing contents here are not directly related, detailed description thereof is omitted.

  In step S700, an overlapping part drawing process is executed. Here, a process is performed on the summary map created in step S500 to draw a portion (section) where two or more routes overlap each other in a display form in which each route can be identified. The processing content at this time will be described in detail later.

  In step S800, coastline drawing processing is executed. Here, based on the coastline shape extracted in step S300, a process of drawing a coastline within a predetermined range from the route is performed. The coastline drawing process may be executed as necessary, and may not be executed. In the present invention, since the processing contents here are not directly related, detailed description thereof is omitted.

  In step S900, the summary map of each route created in step S500 and subjected to the processing in steps S600 to S800 as necessary is displayed on the display monitor 16. At this time, a departure place mark and a destination mark are displayed at the departure place and the destination, respectively. After executing Step S900, the flowchart of FIG. As described above, a plurality of routes to the destination are searched, and a summary map of each route is displayed on the display monitor 16.

  When the processing of the flowchart of FIG. 2 is executed and the summary map of the entire route is displayed on the display monitor 16, the navigation device 1 thereafter instructs the user to select one of the routes. When the user selects one of the routes by operating the input device 17, the selected route is set as a recommended route, a road map around the current location is displayed, and the recommended route is displayed thereon. Then, the vehicle is guided along the recommended route and guided to the destination. At this time, either a normal map or a summary map may be displayed as a road map around the current location. The summary map at this time can also be created by the same process as the flowchart of FIG.

  Next, the contents of the summary map creation process executed in step S500 will be described. In the summary map creation process, a summary map of each route is created by simplifying the road shape of each route by executing a process called a direction quantization process. This direction quantization process will be described below.

  In the direction quantization process, the link of each route is divided by a predetermined number of divisions, and then the road shape is simplified. 3 and 4 are detailed explanatory diagrams for explaining the contents of the direction quantization process. FIG. 3 shows the case where the number of link divisions is 2 (two divisions), and FIG. 4 shows the number of link divisions. For the case of 4 (4 divisions), the contents of each direction quantization process are shown. Hereinafter, the description will be given before the case of the two divisions shown in FIG.

  Reference numeral 30 in FIG. 3A illustrates one of the links included in the searched route. For this link 30, as shown in (b), a point 32 on the link 30 that is farthest from the line segment 31 connecting the both end points is selected. Note that the point 32 selected here corresponds to the aforementioned node or shape interpolation point.

When the point 32 as described above is obtained, next, as shown in (c), line segments 33 and 34 connecting the point 32 and each of the end points of the link 30 are set. The angles formed by the line segments 33 and 34 with respect to the respective reference lines are represented as θ ₁ and θ ₂ . Here, the reference line is a line extending from each end point of the link 30 in a predetermined direction (for example, a true north direction). (C), the angle of the portion sandwiched by the reference line and the line segment 33 from one end point is represented as theta _1. The angle of the portion sandwiched by the reference line and the line segment 34 from the other end point is represented as theta _2.

When the line segments 33 and 34 connecting the point 32 and the both end points of the link 30 are set as described above, the directions of the line segments 33 and 34 are respectively quantized as shown in FIG. . The quantization in the direction here means that the line segments 33 and 34 are respectively rotated around the respective end points so that the aforementioned angles θ ₁ and θ ₂ become an integral multiple of a preset unit angle, respectively. Say. That is, the values of θ ₁ and θ ₂ are corrected by rotating the line segments 33 and 34 so that θ ₁ = m · Δθ and θ ₂ = n · Δθ (n and m are integers), respectively. The values of m and n at this time are set so that θ ₁ and θ ₂ after correction calculated by the above formulas are closest to the original values.

As described above, when the directions of the line segments 33 and 34 are quantized, the angles θ ₁ and θ ₂ between the line segments 33 and 34 and the reference line are corrected in increments of the unit angle Δθ. In FIG. 4D, Δθ = 15 °. Then, the theta ₁ is shows an example in which the angle after correction is set to m = 6 to 90 °, for theta ₂ is the angle of the corrected set to n = 0 to 0 °.

  If the directions of the line segments 33 and 34 are respectively quantized in this way, then the intersection points when the line segments 33 and 34 are respectively extended are obtained. Then, as shown in (d), the lengths of the line segments 33 and 34 are corrected so as to connect the intersections and the end points.

  As described above, the line segments 33 and 34 are obtained, the directions are quantized, and the length is corrected, whereby the direction quantization processing in the case of the division into two for the link 30 is performed. By using these line segments 33 and 34 instead of the link 30, the shape of the link 30 can be simplified. At this time, since the shape of the link 30 is simplified while the positions of both end points of the link 30 are fixed, the position of the adjacent link is not affected. Therefore, by simplifying each link shape of the route using the direction quantization process, the road shape can be easily simplified while maintaining the overall positional relationship of the route.

  Next, the direction quantization process in the case of four divisions will be described. Reference numeral 40 in FIG. 4A illustrates one of the links included in the searched route, as in FIG. 3A. For this link 40, as shown in (b), first, a point 42a on the link 40 that is farthest from the line segment 41a connecting the both end points is selected. Next, line segments 41b and 41c connecting the point 42a and each end point of the link 40 are set, and points 42b and 42c on the link 40 that are farthest from the line segments 41b and 41c are selected. To do. Note that the points 42a to 42c selected here correspond to the above-described nodes or shape interpolation points as in the case of two divisions.

When the points 42a to 42c as described above are obtained, next, as shown in (c), line segments 43 sequentially connecting the end points of the link 40 and the points 42a to 42c in the same manner as in the case of two divisions. , 44, 45 and 46 are set. The angles formed by the line segments 43 to 46 with respect to the respective reference lines are represented as θ ₃ , θ ₄ , θ ₅ and θ ₆ . The reference line at this time is determined not only for the both end points of the link 40 but also for the first selected point 42a located in the middle of the points 42a to 42c.

When the line segments 43 to 46 are set as described above, the direction of each line segment is quantized as shown in (d). At this time, using the point 42a as a storage point, the line segments 44 and 45 are rotated around the storage point 42a, respectively. The line segments 43 and 46 are rotated around the respective end points as in the case of the two division. Here, an example is shown in which Δθ = 15 ° is set in advance, and angles after correction of θ ₃ to θ ₆ are 60 °, 45 °, 180 °, and 60 °, respectively.

  When the directions of the line segments 43 to 46 are quantized in this way, the intersection point when the line segments 43 and 44 are extended next and the intersection point when the line segments 45 and 46 are extended are obtained. Then, as shown in (d), the lengths of the line segments 43 to 46 are corrected so as to connect each intersection and each end point or storage point 42a.

  As described above, the line segments 43 to 46 are obtained, the directions are quantized, and the length is corrected, whereby the direction quantization processing in the case of the quadruple division for the link 40 is performed. By using these line segments 43 to 46 instead of the link 40, the shape of the link 40 can be simplified. At this time, in addition to the positions of both end points of the link 40, the shape of the link 40 is simplified while the position of the storage point 42a is also fixed. Therefore, it is possible to appropriately simplify the road shape while maintaining the overall positional relationship with respect to a route constituted by links having complicated shapes.

  In addition, although the direction quantization process in the case of 2 divisions and 4 divisions has been described above, the direction quantization process can be executed in the same manner for other division numbers. For example, in the case of 8 divisions, first, as in the case of 4 divisions, one point farthest from the line segment connecting the two end points of the link and two points farthest from the two line segments connecting the point and the two end points, respectively. Select. Thereafter, four points farthest from the four line segments connecting the points obtained by adding both end points to these three points are selected. The direction quantization processing is performed by obtaining eight line segments sequentially connecting the total of the seven points thus selected and both end points, and performing the direction quantization and the length correction as described above on these line segments. It can be performed.

  The number of divisions in the direction quantization process may be set in advance, or may be determined based on the link shape. For example, when the points farthest from the line segments connecting the two end points or the points selected so far are sequentially selected as described above (the processing described in (b) of FIGS. 3 and 4), each line is selected. The selection is made sequentially until the distance from the minute to the farthest point becomes a predetermined value or less. In this way, the number of divisions in the direction quantization process can be determined by the shape of the link.

  By sequentially executing the direction quantization process as described above for all the links of each route, it is possible to simplify the road shape of each route and create a summary map. Note that the direction quantization process may not be sequentially performed for each link, but the direction quantization process may be collectively performed for several links.

  Alternatively, in the summary map creation process in step S500, the road shape of each route can be simplified without executing the above-described direction quantization process. Here, a method of simplifying the road shape of each route by approximating each link shape with a curve will be described with reference to FIG.

  FIG. 5A illustrates links 50, 51, and 52 as a part of the links included in the searched route. For these links 50 to 52, first, the link directions quantized at both end points of each link are obtained as shown in (b). Here, the link direction that is closest to the original angle and is an integral multiple of the unit angle is obtained in the same manner as the quantization of the direction of each line segment in the above-described direction quantization process. As a result, a link direction as indicated by an arrow in (b) is obtained for each end point.

  Next, as shown in (c), curves 53, 54 and 55 connecting the end points are obtained to approximate the shape of each link. At this time, the shapes of the curves 53 to 55 are determined so that the direction of the tangent line near the end point of each curve matches the quantized link direction. As a method for obtaining such a curve, for example, there is a spline approximation using a spline function, but a detailed description thereof is omitted here.

  The above-described processing is sequentially executed for all the links of each route, and the road shape is expressed using the obtained curve, thereby simplifying the road shape of each route and creating a summary map. be able to. At this time, as in the case of the direction quantization process, the shape of each link is simplified while the positions of both end points of each link are fixed. Therefore, also in this case, the road shape can be easily simplified while maintaining the overall positional relationship of the route.

  The path on which the direction quantization process has been performed is stored in the RAM 13. Next, the data format of the route stored in the RAM 13 will be described. A description will be given by taking as an example a link on which direction quantization processing in the case of four divisions is performed. Here, it is assumed that the link 40 constitutes a part of the route. FIG. 6A shows the nodes 61 and 62 of the link 40 and the shape interpolation points 64 to 69 and 610 to 613 before the direction quantization processing is performed. On the other hand, FIG. 6B shows the nodes 61 and 62 of the link 40 and the shape interpolation points 42a to 42c after the direction quantization processing is performed. The link 40 in FIG. 6B after the direction quantization process is performed has three shape interpolation points 42a to 42b, whereas FIG. 6A before the direction quantization process is performed. The number of shape interpolation points 64 to 69 and 610 to 613 is 11. Thus, by performing the direction quantization process, the number of shape interpolation points is reduced, and the shape interpolation points are thinned out.

  The link 40 subjected to the direction quantization processing is stored in the RAM 13 in the node data format shown in FIG. 7A, the link data format shown in FIG. 7B, and the path data format shown in FIG. 7C. . The node data format shown in FIG. 7A is a format for storing the node ID of each node stored as map data in the DVD-ROM 19 and the coordinate position after the direction quantization processing of that node is performed. It is. In FIG. 7A, the code “61” is stored in the RAM 13 as the node ID of the node 61 in FIG. 6, and the coordinates (X1, Y1) of the node 61 and the altitude of the node 61 are stored in the RAM 13.

  The link data format shown in FIG. 7B is the code “40” as the link ID of each link stored as map data in the DVD-ROM 19 and the node IDs of the start point node 61 and the end point node 62 of the link. Codes “61” and “62” are stored. In the link data format, the number of shape interpolation points 42a to 42c on the link 40 and their positions (Xb, Yb), (Xa, Ya), (Xc, Yc) are also stored.

  The route data format shown in FIG. 7C is that an identification symbol (route ID) is given to each route that has undergone direction quantization processing, and the number of links and links that constitute that route for each route ID. ID is stored in this format. Here, the route ID of the route including the link 40 is R1. The RAM 13 stores R1 which is the route ID of the route, the number n of links constituting the route, and L1 to Ln as IDs of the links constituting the route. When a plurality of searched routes are displayed, the link ID stored in the route data format of each searched route is referred to, and when the same link ID exists, the searched routes having the same link ID are the same link ID. It can be seen that there is overlap in the position of the link, that is, part of the route passes through the same route.

  Next, the overlapping partial drawing process executed in step S700 will be described. First, the summary map after the overlapping part drawing process in step S700 will be described in comparison with the summary map before the overlapping part drawing process. FIGS. 8A and 8B respectively show a summary map 81 before the overlapping portion rendering process in step S700 and a summary map 82 after the overlapping portion rendering process in step S700. The summary maps 81 and 82 are summary maps in which a plurality of routes are displayed in the full route display after the route search of the navigation device 1 is performed.

  In the summary maps 81 and 82, five search routes 85, 86, 87, 88 and 89 connecting the current location 83 to the destination 84 are shown. In the section 810, the search route 85 passes through the elevated road, and the search route 86 and the search route 87 pass through the underpass road.

  In the summary map 81 before the overlapping portion drawing process, whether the search routes 85, 86, and 87 all pass the same road in the section 810, or one of the search routes passes through the elevated road and the other search I don't know if the route is passing over an elevated road. Therefore, in this embodiment, when the road under the elevated road overlaps with the elevated road, it is collectively represented by a pipe. That is, as shown in FIG. 8B, in the summary map 82 after the overlapping portion drawing processing, the search route 86 and the search route 87 in the section 810 are drawn so as to pass through the pipe 811. As a result, the occupant can recognize that the search route 85 passes through the elevated road, and the search route 86 and the search route 87 pass through the road under the elevated.

  Next, the contents of the overlapping partial drawing process executed in step S700 will be described with reference to the flowchart of FIG. FIG. 9 is a flowchart showing the overlapping partial drawing process executed in step S700.

  In step S701, information on a plurality of search paths on which the direction quantization processing stored in the RAM 13 is performed is searched. In step S702, it is determined from the search route information whether there is a search route with a portion where links of the same position coordinates exist among a plurality of search routes, that is, a section with overlapping display. If there is a searched route with a section that is displayed in duplicate, an affirmative determination is made and the process proceeds to step S703. If there is no search path with a section displayed in duplicate among a plurality of search paths, a negative determination is made and the overlapping partial drawing process ends.

  In step S703, it is determined whether there are both a search route that passes through the elevated road and a search route that passes through the road under the elevated road in the section in which a plurality of search routes are displayed in duplicate from the altitude information of the node. To do. If an affirmative determination is made, the process proceeds to step S704, and the search paths in the overlapping display section (hereinafter referred to as the overlapping display section) are translated from each other by half the line width of each search path. Then, the process proceeds to step S705, and along the search route passing through the underpass road, an opaque pipe is displayed so as to overlap a part of the search route passing through the overpass road, and the search route passing through the underpass road The drawing process is performed so that the image passes through the opaque pipe and is displayed. If all of the plurality of search routes in the overlapping display section pass through the elevated road or pass through the road under the elevated, a negative determination is made, and the process proceeds to step S706. In step S706, the search path of the overlapping display section is translated by half the line width of one search path. Then, the overlapping partial drawing process ends.

  A summary map of each route that has been subjected to the overlapping portion drawing processing is displayed on the display monitor 16, and in a section where the search route that passes through the elevated road and the search route that passes through the road under the elevated route are displayed in duplicate, The search route that passes through the underpass road is displayed so as to pass through the pipe.

  Next, the processing in steps S705 and S706 in FIG. 9 will be described in more detail with reference to FIG. As shown in FIG. 10A, a case will be described in which the search route 101 passing through the elevated road and the search route 102 passing through the underpass road overlap. In step S705 of FIG. 9, as shown in FIG. 10B, the search path 101 is translated in the direction of the arrow 103 by half the length of the line width of the search path 101. On the other hand, the search path 102 is translated in the direction of the arrow 104 at a length half the length of the line width of the search path 102. In step S706 of FIG. 9, the drawing process is performed so that the pipe 105 is displayed in a manner that the search path 102 seems to pass through the pipe 105 as shown in FIG. The displayed pipe 105 is opaque, and if the displayed pipe 105 is too thick, the search path 101 is hidden behind the pipe 105 and cannot be seen. Therefore, the pipe 105 has a thickness overlapping with a part of the search path 101. The drawing process is performed so that is displayed.

According to the navigation device according to the embodiment described above, the following operational effects can be obtained.
(1) Since the search route passing through the elevated road is displayed so as to pass through the pipe, even if the amount of shifting the search route in the overlapping display section is small, the displayed search route is searched through the elevated road. It is possible to distinguish between a route and a searched route passing through a road under an elevated route. This is particularly effective when there is little space to display by shifting the search route.
(2) When there are a plurality of search routes that pass through the road under the elevated route, the plurality of search routes that pass through one road are collectively displayed so as to pass through one pipe. As a result, even if the number of displayed search routes is large, it is difficult to understand which route passes the search route passing through the elevated road and the search route passing through the road under the elevated road. There is nothing.
(3) If the link shape is simplified with the positions of both end points of each link being fixed, the shape of each link can be simplified without affecting the position of the adjacent link. As a result, the road shape can be easily simplified while maintaining the overall positional relationship of the road, so even if the road shape is simplified over a long distance, the position of the road will deviate significantly from the original position. There is no. By the way, if the search route that passes through the underpass road is displayed so as to pass through the pipe, the search of the overlapping display section is performed in order to distinguish the search route that passes the overpass road and the search route that passes the underpass road. The amount of shifting the route is small. Therefore, the effect of simplifying the road shape that the position of the road is not significantly shifted from the original position is not reduced by the overlapping portion drawing process.
(4) In the direction quantization process in the case of four divisions, in addition to the positions of both end points of the link 40, the link shape is simplified while the position of the storage point 42a is also fixed. In this way, it is possible to appropriately simplify the road shape while maintaining the overall positional relationship even for roads configured with links having complicated shapes. By the way, if the search route that passes through the underpass road is displayed so as to pass through the pipe, the search of the overlapping display section is performed in order to distinguish the search route that passes the overpass road and the search route that passes the underpass road. The amount of shifting the route is small. Therefore, even for roads composed of links with complicated shapes, the effect of direction quantization processing that can appropriately simplify the road shape while maintaining the overall positional relationship is reduced by overlapping part drawing processing Never do.
(5) Since the indication that the search route passes through the pipe is a concise indication, the search route that passes through the elevated road without any sense of incongruity in the simplified map with a simplified road shape or the like or under the overpass Display for distinguishing the search route passing through the road.

  In the embodiment described above, the pipe to be displayed is opaque, but may be made semi-transparent so that it can be understood which search route passes through the pipe. In addition, the search route in the overlapping display section is displayed by translating each other by half the line width of the search route, but is the search route passing through the elevated road or the search route passing through the road under the elevated road? As long as it can be distinguished, the amount of movement to be translated is not particularly limited. Further, the search route passing through the elevated road is displayed so as to pass through the pipe, but the search route passing through the elevated road may be displayed so as to pass through the pipe.

  In the above embodiment, an example has been described in which the navigation device reads map data from a storage medium such as a DVD-ROM to create a summary map, but the present invention is not limited to this. For example, the present invention can be applied to a communication navigation apparatus that downloads map data from an information distribution center using wireless communication using a mobile phone or the like. In this case, the information distribution center performs the summary map creation process and the pipe display process in the overlapping part drawing process as described above, and the result is output from the information distribution center and distributed to the navigation device. Also good. That is, the information distribution center includes a device that creates a summary map and a device that outputs the summary map to the outside.

  In the above embodiment, a summary map is created by simplifying the road shape of each route by direction quantization processing or curve approximation processing. However, as disclosed in Japanese Patent Application Laid-Open No. 2004-139485, direct / direct The summary map may be simplified by evolution processing, horizontal / vertical processing, smoothing processing, connection processing, and the like.

  The present invention is not limited to the above embodiment. Other embodiments conceivable within the scope of the technical idea of the present invention are also included in the scope of the present invention.

It is a block diagram which shows the structure of the navigation apparatus by one Embodiment of this invention. It is a flowchart of the process performed when searching a some route to the set destination and displaying the summary map of each route. It is a figure for demonstrating the content of the direction quantization process in the case of 2 division utilized when producing a summary map. It is a figure for demonstrating the content of the direction quantization process in the case of 4 divisions similarly. It is a figure for demonstrating the method of simplifying the road shape of each path | route by approximating each link shape with a curve. (A) is a figure which shows a link, a node, and a shape interpolation point before performing the direction quantization process in the case of 4 divisions, (b) is after the direction quantization process in the case of 4 divisions is performed It is a figure which shows a link, a node, and a shape interpolation point. It is a figure explaining the storage format of the path | route where the direction quantization process memorize | stored in RAM was performed. It is the figure which showed the summary map before performing an overlapping part drawing process, and the summary map after performing an overlapping part drawing process. It is a flowchart which shows the process of an overlapping part drawing process. (A) is a figure which shows a mode that two search paths have overlapped. (B) is a figure which shows a mode that the location where two search paths overlap was translated. (C) is the figure which processed so that one of the search paths moved in parallel might pass the inside of a pipe.

Explanation of symbols

1 Navigation device 11 Control circuit 12 ROM
13 RAM
14 Current location detection device 15 Image memory 16 Display monitor 17 Input device 18 Disk drive 19 DVD-ROM
30, 40, 50, 51, 52 Link 85-89, 101, 102 Search path 811, 105 Pipe

Claims (5)

Search means for calculating a plurality of search paths;
A summary map creating means for creating a summary map with a simplified road shape based on the road map data;
The summary map creating means includes at least one of the plurality of search routes in which at least two search routes are overlapped and displayed for at least one of the elevated roads and at least one of the roads under the elevated route. A tubular mark is drawn so as to overlap with a part of the search route passing through the other road along the search route passing through the other road, and the search route passing through the one road passes through the tubular mark A summary map display device characterized in that display is performed as described above. The summary map display device according to claim 1,
The summary map creation device displays the plurality of search routes so as to pass through the tubular mark when there are a plurality of search routes passing through the one road. In the summary map display device according to claim 1 or 2,
The road map data represents the shape of the road by the shape of the link set for each predetermined road section,
The summary map creating means creates a summary map on which the plurality of searched routes are displayed by fixing the positions of both end points of the link and simplifying the shape of the link. Display device. In the summary map display device according to claim 3,
The summary map creation means selects one of points set in advance on the link as a storage point, and fixes the position of the storage point and the both end points to simplify the shape of the link. Summary map display device characterized by the above. In the summary map display device according to claim 3 or 4,
Point selection means for selecting any of the points set in advance on the link;
Line segment setting means for setting a plurality of second line segments that connect the point selected by the point selection means and each of the both end points in order;
The second line segment set by the line segment setting means is configured so that an angle formed with respect to a predetermined direction determined in advance is an integral multiple of a predetermined unit angle set in advance. Direction correction means for correcting the direction of each of the line segments;
Intersection detecting means for obtaining an intersection when each of the second line segments whose directions are corrected by the direction correcting means is extended;
Length correction means for correcting the length of each of the second line segments so as to connect the intersection detected by the intersection detection means and either one of the both end points or the selected point. And further comprising
The point selection means further selects a point farthest from a third line segment connecting each of the end points and the selected point among points preset on the link,
The summary map creation means uses the second line segments whose lengths are corrected by the length correction means to simplify the shape of the link, thereby displaying the plurality of search paths. A summary map display device characterized by creating a map.

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