JP2007171229A - Map display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To display a 3-dimensional map image in which a realistic city landscape is regenerated by displaying buildings having big influence with distinctive appearance in high reality, and by displaying the other buildings in low reality. <P>SOLUTION: In the 3-dimensional map image, the building which is conspicuous on appearance and a structure which a driver tends to see such as a sign etc. installed on a road, such as traffic lights 28, 29 and buildings 30, 31 are displayed in high reality, based on real data. Also, for example, the structure which the driver does not tend to see, such as a non-distinctive building 32 and trees 33 to 36, having no influence on real feeling in viewing of a whole 3-dimensional map image, is displayed in low reality based on non-real data. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an apparatus for displaying a three-dimensional map.

  There is known an apparatus capable of displaying a three-dimensional cityscape even in a small computer system having a low processing capacity by generating a three-dimensional model of a building according to a plurality of three-dimensional model patterns prepared in advance ( Patent Document 1). In addition, data of the bottom shape and height information of each building is stored in map data, and the three-dimensional shape of the building is drawn using the map data to reproduce a three-dimensional and realistic cityscape. An apparatus is also known (see Patent Document 2).

JP 2002-298162 A JP 2005-316702 A

  The apparatus disclosed in Patent Literature 1 displays a three-dimensional model generated according to a three-dimensional model pattern prepared in advance for all buildings. Therefore, a building that has a large influence on the landscape due to its characteristic appearance is displayed in the same shape as other buildings, and thus lacks realism. On the other hand, in the apparatus disclosed in Patent Document 2, since all buildings are displayed realistically regardless of the influence on the landscape, the amount of processing data at the time of drawing increases, and it is necessary to use a CPU with high processing capacity. . Therefore, unnecessary cost increases may occur.

The map display device according to the invention of claim 1 has a control circuit for executing various processes, and using the control circuit, real data for displaying the appearance of the structure in a highly realistic manner, and the structure The map data including non-real data for displaying the appearance of the image in low real is read, and the three-dimensional image of the structure based on the real data and the three-dimensional image of the structure based on the non-real data are included in one map image. 3D map images mixed together are displayed, and the created 3D map images are displayed on a display monitor.
According to a second aspect of the present invention, in the map display device of the first aspect, the ratio of the stereoscopic image of the structure based on the real data and the stereoscopic image of the structure based on the non-real data is changed according to the processing load of the control circuit. Is.
According to a third aspect of the present invention, in the map display device of the first or second aspect, for the same structure, the amount of non-real data is smaller than that of real data.
According to a fourth aspect of the present invention, in the map display device of the third aspect, the real data and the non-real data include bottom data for representing the bottom shape of the structure and polygons for representing the wall surface of the structure by a plurality of polygons. For the same structure, at least one of the number of bottom vertices based on bottom surface data and the number of polygons based on polygon data is less for non-real data than for real data. .

  According to the present invention, buildings that have a large influence on the landscape due to their characteristic appearance are displayed in high realism, and buildings that are not so are displayed in low realism, and there is a real feeling while avoiding unnecessary cost increases. A three-dimensional map image that reproduces the cityscape can be displayed.

  A configuration of a navigation apparatus according to an embodiment of the present invention is shown in FIG. The navigation device 1 of FIG. 1 is mounted on a vehicle, displays a three-dimensional map image simulating a landscape seen in front of the host vehicle with a three-dimensional realistic image, and displays the host vehicle up to a set destination. To guide you. This provides the driver with realistic navigation information that is easy to understand.

  The navigation device 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 the processing executed in the control circuit 11, a recommended route to the destination is searched based on the map data recorded on the DVD-ROM 19, and a three-dimensional map image simulating the scenery ahead of the host vehicle is created. And displayed on the display monitor 16.

  The current location detection device 14 is a device that detects the current location of the host vehicle, that is, the 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 the vehicle speed, and a GPS signal from a GPS satellite. It consists of a GPS sensor 14c to be detected. The navigation device 1 determines a route search start point when searching for a recommended route based on the vehicle position detected by the current location detection device 14, and a viewpoint when determining the creation range of the three-dimensional map image The position can be set.

  The image memory 15 temporarily stores image data to be displayed on the display monitor 16. This image data includes data for drawing a three-dimensional map image created by the control circuit 11. Using the image data stored in the image memory 15, various images such as a three-dimensional map image simulating a landscape in front of the host vehicle are 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 in accordance with a screen instruction displayed on the display monitor 16 to set a destination by designating a place name, a position on the map, a facility name, etc., and search for a route to the destination. The navigation device 1 can be started. When the destination is set according to the operation of the user's input device 17, the route calculation to the set destination is performed by a predetermined algorithm using the current location detected by the current location detection device 14 as a route search start point. A recommended route to the destination is required. In accordance with the recommended route thus obtained, guidance to the destination is performed.

  The disk drive 18 reads map data used for searching a recommended route and creating a three-dimensional map image 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 recorded on the DVD-ROM 19 represents route calculation data for recommended route calculation, route guidance data such as intersection names and road names used when guiding the vehicle to the destination according to the recommended route, and roads. The road data includes structure data representing structures such as buildings and various structures displayed on the three-dimensional map image.

  There are two types of structure data. One is data with a high degree of realism, and the appearance of each structure can be faithfully reproduced and displayed in a highly realistic manner. Such structure data is called real data. The other is data that is less real than real data, and displays the appearance of each structure in a low real manner. Such structure data is called non-real data. Here, the real degree refers to the degree that looks like the real thing. That is, high real means that it looks as if the real thing is displayed as it is, and low real means that it looks close to the real thing but is simplified or partially omitted. Such real data and non-real data are set for each structure.

  The real data and the non-real data each include three-dimensional shape data for displaying the structure in three dimensions. This includes bottom surface data for representing the bottom surface shape of the structure, polygon data for representing the wall surface shape of the structure with a plurality of polygons, and image data to be pasted on the polygon. Various data such as texture data for representing patterns, colors, and the like are included. Note that the bottom surface data is represented as a plurality of vertex coordinates constituting the bottom surface. Polygon data is represented as the number of polygons and a vertex coordinate sequence forming each polygon.

  Real data and non-real data differ in the number of vertices of the bottom surface, the number of polygons and the number of vertices of each polygon, the degree of realism of texture data, etc. in the three-dimensional shape data. In real data, a detailed shape of a structure can be reproduced by constructing a bottom surface using more vertices than in non-real data, or by increasing the number of polygons and polygon vertices. In addition, for the texture data included in the real data, a high-resolution image, an image created from a photograph of the real object, or the like is used in order to obtain an appearance close to the real object. On the other hand, in the non-real data, the shape of the structure is simplified by reducing the number of vertices and polygons on the bottom surface compared to the real data. In addition, as the texture data included in the non-real data, a low-resolution image, an image patterned using a certain color or pattern, or the like is used.

  When creating a three-dimensional map image in the control circuit 11, a difference occurs in the processing load of the control circuit 11 when using real data and when using non-real data. When real data is used, the structure can be expressed in a highly realistic manner, but a large amount of data processing is required, which increases the processing load. On the other hand, when non-real data is used, the structure is represented as low real, but the amount of non-real data is less than that of real data for the same structure, so the processing load can be reduced. it can.

  An example of a three-dimensional map image displayed on the display monitor 16 in the navigation device 1 is shown in FIG. The three-dimensional map image includes a center line 20, lane boundary lines 21 and 22, traveling direction arrows 23, 24 and 25, crosswalks 26 and 27, traffic lights 28 and 29, buildings 30, 31 and 32, and roadside trees 33 to 33. 36 and the like are displayed three-dimensionally. A signboard 37 is installed in the upper part of the building 31.

  In the three-dimensional map image displayed on the display monitor 16, structures that are easily noticed by the driver, such as buildings that are conspicuous on the exterior and signs installed on the road, are high on the basis of real data as described above. Realistic display. In the example of FIG. 2, the traffic lights 28 and 29 and the buildings 30 and 31 correspond to this. Further, the center line 20, lane boundary lines 21 and 22, road direction arrows 23, 24 and 25, and pedestrian crossings 26 and 27, which are road markings, are similarly displayed on the three-dimensional map image based on real data. .

  On the other hand, structures such as non-characteristic buildings and roadside installations that do not attract much attention from the driver and have little effect on the real appearance of the entire three-dimensional map image are non-real data as described above. Based on the low real display. In the example of FIG. 2, the building 32 and the roadside trees 33 to 36 correspond to this.

  As described above, in one 3D map image, a stereoscopic image of a structure that is highly realistic based on real data and a stereoscopic image of a structure that is lowly realistic based on non-real data In addition, the load on the control circuit 11 can be reduced to simplify the hardware and improve the processing speed while maintaining the real appearance of the entire three-dimensional map image. As to whether the stereoscopic image of each structure is displayed based on real data or non-real data, in addition to the driver's attention as described above, the type of structure and surrounding structures It is determined in advance for each structure in consideration of the installation density and the like.

  FIG. 4 shows a flowchart of processing executed in the control circuit 11 when a three-dimensional map image as shown in FIG. 2 is displayed on the display monitor 16. By executing this flowchart at every predetermined processing cycle, the contents of the three-dimensional map image are updated. In step S10, the creation range of the three-dimensional map image is set. At this time, a viewpoint position is determined based on the vehicle position detected by the current position detection device 14, and a predetermined direction and a range within the viewpoint position are set as a three-dimensional map image creation range.

  In step S20, the map data within the creation range of the three-dimensional map image set in step S10 is read from the DVD-ROM 19 using the disk drive 18. This map data includes real data and non-real data for each structure existing within the creation range of the three-dimensional map image. In step S30, a structure to be displayed in the three-dimensional map image is selected by selecting any structure from the map data read in step S20.

  In step S40, it is determined whether to use real data or non-real data in order to create a stereoscopic image of the structure selected in step S30. If it is determined that real data is used, the process proceeds to step S50. If it is determined that non-real data is used, the process proceeds to step S60. In the map data, information necessary for the determination in step S40 is recorded for each structure according to a predetermined condition. The determination in step S40 is performed by referring to the information.

  In step S50, a three-dimensional image of the structure is created based on real data for the structure selected in step S30. Thereby, the selected structure is displayed in a highly realistic manner. If step S50 is performed, it will progress to step S70.

  On the other hand, in step S60, a three-dimensional image of the structure is created based on the non-real data for the structure selected in step S30. Thereby, the selected structure is displayed in a low real manner. After step S60 is executed, the process proceeds to step S70.

  In step S70, it is determined whether all the structures within the creation range of the three-dimensional map image have been selected in step S30 executed so far. If all the structures have been selected, the process proceeds to step S80. If there is a structure that has not yet been selected, the process returns to step S30, one of them is selected, and the above process is repeated.

  In step S80, a three-dimensional map image is created. The three-dimensional map image includes a three-dimensional image of the structure based on the real data created by the process of step S50 executed so far and a three-dimensional structure of the structure based on the non-real data created by the process of step S60. The image is mixed. In step S90, the three-dimensional map image created in step S80 is displayed on the display monitor 16. If step S90 is performed, the flowchart of FIG. 4 will be complete | finished. Through the processing described above, a three-dimensional map image as shown in FIG. 2 is displayed on the display monitor 16.

  In addition, when displaying a three-dimensional map image according to the flowchart of FIG. 4, according to the processing load of the control circuit 11, by switching and displaying real data and non-real data for some structures, real data is displayed. You may make it change the ratio of the three-dimensional image of the structure based on, and the three-dimensional image of the structure based on non-real data in a three-dimensional map image. In other words, when the processing load is relatively small, the structure is displayed in a highly realistic manner based on the real data, but when the processing load is greater than a predetermined state, the structure is displayed based on the non-real data. By displaying in low real, the processing load of the control circuit 11 itself is reduced. By doing so, it is possible to select appropriate processing contents according to the processing load state of the control circuit 11 and prevent a reduction in processing speed.

  FIG. 3 is an example of a three-dimensional map image displayed using non-real data with respect to a part of the structure displayed using real data in FIG. In this three-dimensional map image, the building 31 is displayed in low real using non-real data, and therefore has a form different from that in FIG. 2 and the signboard 37 is not displayed. As described above, when a processing load is small, a part of the structure that creates a stereoscopic image based on real data can be displayed in a low real state by creating a stereoscopic image based on non-real data when the processing load is large. To do. It should be noted that which structure is to be displayed by non-real data when the processing load increases can be set in advance.

According to the embodiment described above, the following operational effects can be achieved.
(1) Using the control circuit 11, map data including real data and non-real data is read (step S20), and a three-dimensional image of the structure based on the real data and a three-dimensional image of the structure based on the non-real data Creates a three-dimensional map image mixed in one map image (step S80). The three-dimensional map image created in this way is displayed on the display monitor 16 (step S90). Because of this, buildings that have a large impact on the landscape due to their characteristic appearance are displayed in high realism, and buildings that are not so are displayed in low realism, avoiding unnecessary cost increases and providing a sense of realism. A three-dimensional map image that reproduces the cityscape can be displayed.

(2) If the ratio of the stereoscopic image of the structure based on real data and the stereoscopic image of the structure based on non-real data is changed in the three-dimensional map image according to the processing load of the control circuit 11, the control circuit It is possible to select appropriate processing contents according to the 11 processing load states and prevent a reduction in processing speed.

(3) For the same structure, at least one of the number of bottom vertices based on bottom surface data and the number of polygons based on polygon data is less real than real data because non-real data is less than real data. The amount of data is less for data. Therefore, the processing load when using non-real data can be reduced as compared with real data.

  Note that the map display method as described above can be applied to other than the vehicle navigation device. That is, the present invention reads map data including real data and non-real data, and creates a three-dimensional map image in which a stereoscopic image of a structure based on real data and a stereoscopic image of a structure based on non-real data are mixed. The present invention can be applied to a map display device that displays the image.

  Each embodiment and various modifications described above are merely examples, and the present invention is not limited to these contents as long as the features of the invention are not impaired. When interpreting the invention, there is no limitation or restriction on the correspondence between the matters described in the above embodiments and the matters described in the claims.

It is a block diagram which shows the structure of the navigation apparatus by one Embodiment of this invention. It is an example of a three-dimensional map image. It is an example of the three-dimensional map image displayed using the non-real data about a part of structure of FIG. It is a flowchart performed when displaying a three-dimensional map image.

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

Claims (4)

It has a control circuit for executing various processes, and using that control circuit,
Reads map data including real data for displaying the appearance of the structure in high reality and non-real data for displaying the appearance of the structure in low reality.
Creating a three-dimensional map image in which a three-dimensional image of the structure based on the real data and a three-dimensional image of the structure based on the non-real data are mixed in one map image;
A map display device that displays the generated three-dimensional map image on a display monitor. The map display device according to claim 1,
A map display device, wherein a ratio of a stereoscopic image of a structure based on the real data and a stereoscopic image of a structure based on the non-real data is changed according to a processing load of the control circuit. The map display device according to claim 1 or 2,
A map display device characterized in that the non-real data has a smaller data amount than the real data for the same structure. The map display device according to claim 3,
The real data and the non-real data each include bottom data for representing the bottom shape of the structure and polygon data for representing the wall surface shape of the structure by a plurality of polygons,
At least one of the number of bottom vertices based on the bottom surface data and the number of polygons based on the polygon data for the same structure is less in the non-real data than in the real data. .

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