JP6143871B2 - Map display system, map display method and program - Google Patents

Description

  The present invention relates to a map display system, a map display method, and a program. The present invention relates to a texture prefetching device, for example.

  Conventionally, there is a navigation device that prefetches a texture (image) for a three-dimensional model when drawing a three-dimensional map (for example, see Patent Document 1).

JP 2003-294457 A

  A conventional navigation device predicts a map area where a vehicle is likely to pass in the future based on a route set by a user or a type of road on which the vehicle is traveling. The navigation device prefetches the texture for the three-dimensional model linked to the map area. Thereby, the navigation apparatus can immediately perform texture mapping on the three-dimensional model when the map area is displayed due to the movement of the vehicle.

  However, when the route is not set and the vehicle is not running, the navigation device cannot prefetch the texture. When the user performs a scroll operation in such a case, it takes time to perform texture mapping of the map area displayed after scrolling. That is, the conventional navigation device has a problem that when the map area to be displayed is changed by the scroll operation, the texture mapping cannot be immediately performed on the three-dimensional model.

An object of the present invention is to prefetch an image (for example, a texture for a three-dimensional model) of an object existing in a map area that may be displayed in the future by a user operation (for example, a scroll operation) .

A map display system according to one aspect of the present invention includes:
For a display device that displays a map, a display unit that displays an image of an object existing in a display area in the display device of the map on the map;
An acquisition unit that acquires an image that the display unit displays on the display device from a storage device that stores an image of an object existing on the map;
A storage unit for storing definition information defining a plurality of divided areas into which the map is divided;
An input unit that accepts user operations;
Each time the display area of the map on the display device is changed by the operation received by the input unit , the divided area is expanded from the plurality of divided areas based on the definition information stored by the storage unit. In this case, a divided area that overlaps at least a part of the display area after the change of the map is selected as an area outside and near the display area after the change of the map, and after the change of the map to the acquisition unit And a control unit that acquires an image of an object existing in a region near and outside the display region.

According to one aspect of the present invention, the map display system is an image of an object (for example, a texture for a three-dimensional model ) that exists in a map area that may be displayed in the future by a user operation (for example, scroll operation). ) Can be read ahead. For this reason, the map display system can immediately display an image when the map area is displayed by a user operation .

1 is a diagram showing a configuration of a map display system according to Embodiment 1. FIG. 1 is a block diagram showing a detailed configuration of a map display system according to Embodiment 1. FIG. FIG. 3 is a block diagram illustrating a processing configuration of a control unit of the map display system according to the first embodiment. The latitude longitude plane projection figure which shows the example of a three-dimensional model. The oblique projection figure corresponding to FIG. The table | surface which shows the example of the model data list | wrist of the map display system which concerns on Embodiment 1. FIG. The table | surface which shows the example of the texture data list | wrist of the map display system which concerns on Embodiment 1. FIG. 3 is a flowchart showing a preprocessing procedure of the map display system according to the first embodiment. The figure which shows the example of a division area. The table | surface which shows the example of the reference texture list | wrist of the map display system which concerns on Embodiment 1. FIG. The table | surface which shows the example of the expansion area | region list of the map display system which concerns on Embodiment 1. FIG. 5 is a flowchart showing a procedure of real-time processing of the map display system according to the first embodiment. The latitude longitude plane projection figure which shows the example of a display area. FIG. 14 is an oblique projection corresponding to FIG. 13. The figure which shows the example of the expansion area which overlaps with a display area. The block diagram which shows the process structure of the control part of the map display system which concerns on Embodiment 2. FIG. 9 is a flowchart showing a preprocessing procedure of the map display system according to the second embodiment. The table | surface which shows the example of the division | segmentation area | region list of the map display system which concerns on Embodiment 2. FIG. 9 is a flowchart showing a procedure of real-time processing of the map display system according to the second embodiment. The figure which shows the example of the expansion area which overlaps with a display area. FIG. 5 is a diagram showing a configuration of a map display system according to a third embodiment. FIG. 9 is a block diagram showing a detailed configuration of a map display system according to Embodiment 3. The figure which shows the example of the hardware constitutions of each apparatus of the map display system which concerns on Embodiment 1-3.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Embodiment 1 FIG.
FIG. 1 is a diagram showing a configuration of a map display system 100 according to the present embodiment.

  In FIG. 1, the map display system 100 includes a navigation device 101.

  The navigation device 101 is mounted on a vehicle.

  The navigation device 101 includes a display device 200. The display device 200 displays a three-dimensional map. A three-dimensional map is an example of a map. In the present embodiment, the three-dimensional map can be replaced with another type of map such as a two-dimensional map. The display device 200 is implemented by, for example, an LCD (Liquid / Crystal / Display).

  The navigation device 101 further includes a storage device 300. The storage device 300 stores a texture 500 for a 3D model of an object (for example, a building) existing on a 3D map. The texture 500 is an example of an object image. In the present embodiment, the texture 500 can be replaced with other types of images. The storage device 300 is implemented by, for example, an HDD (Hard / Disk / Drive) or an SSD (Solid / State / Drive).

  The navigation device 101 further includes an input device 400. The input device 400 is operated by a user such as a vehicle driver. The input device 400 is implemented with operation buttons, for example. Alternatively, the input device 400 is mounted with a touch panel integrated with the display device 200.

  FIG. 2 is a block diagram illustrating a detailed configuration of the map display system 100.

  2, the map display system 100 includes a detection unit 111, a display unit 112, an acquisition unit 113, an input unit 114, a storage unit 115, and a control unit 116. The detection unit 111, the display unit 112, the acquisition unit 113, the input unit 114, the storage unit 115, and the control unit 116 are all provided in the navigation device 101.

  The detection unit 111 detects the current position of the vehicle on which the display device 200 is mounted. The detection unit 111 detects the current latitude and longitude of the vehicle using, for example, a GPS (Global Positioning System) receiver and various sensors such as a gyro sensor and a vehicle speed sensor.

  The display unit 112 causes the display device 200 to display a texture 500 for a three-dimensional model of an object (for example, a building) existing in the display area of the display device 200 of the three-dimensional map on the three-dimensional map. When the position detected by the detection unit 111 is present in the display area of the 3D map display device 200, the display unit 112 further displays a mark indicating the position on the 3D map on the display device 200. Let

  The acquisition unit 113 acquires the texture 500 that the display unit 112 displays on the display device 200 from the storage device 300.

  The input unit 114 receives a user's scroll operation via the input device 400. The scroll operation is an example of the operation. In the present embodiment, the input unit 114 may accept other types of operations such as a zoom-in operation and a zoom-up operation together with the scroll operation instead of the scroll operation.

  The storage unit 115 stores definition information 600. The definition information 600 includes divided region information 601 that defines a plurality of divided regions obtained by dividing the three-dimensional map. The definition information 600 further includes enlargement area information 602 that defines a plurality of enlargement areas each obtained by enlarging a plurality of divided areas by a certain margin. The definition information 600 further includes correspondence information 603 that defines the correspondence between a plurality of divided areas and a plurality of enlarged areas.

Whenever the display area in the 3D map display device 200 is changed by the scroll operation received by the input unit 114, the control unit 116 changes the "area outside and near the display area after the 3D map change". Determine as follows.
(1) The control unit 116 refers to the definition information 600 stored in the storage unit 115.
(2) Based on the enlarged area information 602 of the definition information 600 referred to in (1), the control unit 116 selects an enlarged area that overlaps at least a part of the display area after the change of the three-dimensional map from a plurality of enlarged areas. select.
(3) Based on the correspondence information 603 of the definition information 600 referred to in (1), the control unit 116 selects a divided region corresponding to the enlarged region selected in (2) from a plurality of divided regions.
(4) The control unit 116 determines the divided region selected in (3) as “a region outside and near the display region after the three-dimensional map is changed”.

  The control unit 116 specifies the texture 500 for the three-dimensional model of the object existing in the region determined in (4) based on the divided region information 601 of the definition information 600 referenced in (1). The control unit 116 causes the acquisition unit 113 to acquire the specified texture 500. Thereby, the acquisition unit 113 can prefetch the texture 500 for the three-dimensional model of the object existing in the map area that may be displayed in the future by the user's scroll operation. For this reason, the display part 112 can display the texture 500 immediately, when the map area | region will be displayed by a user's scroll operation.

  In (2) to (4), the control unit 116 may select a specific divided region by referring only to the divided region information 601 without referring to the enlarged region information 602 and the correspondence relationship information 603. The specific divided area is a divided area that overlaps at least a part of the display area after the change of the three-dimensional map when the divided area is enlarged by the predetermined margin described above. If the control unit 116 does not refer to the enlarged region information 602 and the correspondence relationship information 603, the storage unit 115 may not store the enlarged region information 602 and the correspondence relationship information 603. Therefore, the storage capacity can be reduced.

  FIG. 3 is a block diagram illustrating a processing configuration of the control unit 116.

  In FIG. 3, the processing of the control unit 116 includes pre-processing 120 that is executed before the operation of the model display function, and real-time processing 130 that is performed during the operation of the model display function.

  The pre-processing 120 includes an area division process 121, a model determination process 122, a reference texture list creation process 123, and an enlarged area calculation process 124.

  The area division processing 121 is a process of dividing the model storage area indicated by the model storage area data 141 into a plurality of division areas according to the number of divisions indicated by the area division number data 142. The model storage area is a storage range of the three-dimensional model. The model storage area data 141 and the area division number data 142 are stored in the storage unit 115 as part of the definition information 600.

  The model determination process 122 is a process for determining to which divided region each three-dimensional model indicated by the model data list 143 belongs. The model data list 143 is stored in the storage unit 115 as part of the definition information 600.

  The reference texture list creation process 123 is a process for creating the reference texture list 144. The reference texture list 144 is data indicating the index of the texture 500 referred to by the three-dimensional model belonging to each divided area for each divided area. The reference texture list 144 is stored in the storage unit 115 as part of the definition information 600.

  The enlarged area calculation process 124 is a process for calculating an enlarged area and creating an enlarged area list 146. The enlarged area is an area that can be created by expanding each divided area calculated by the area dividing process 121 by the margin indicated by the prefetch determination margin data 145. The enlarged area list 146 is data indicating an enlarged area for each divided area. The prefetch determination margin data 145 and the enlarged area list 146 are stored by the storage unit 115 as part of the definition information 600.

  The real-time process 130 includes a display center acquisition process 131, a display area calculation process 132, a duplication determination process 133, a reference texture extraction process 134, and a reference texture prefetch process 135.

  The display center acquisition process 131 is a process for acquiring the center coordinates of the display range moved by the user's scroll operation.

  The display area calculation process 132 is a process for calculating a display area based on the center coordinates acquired by the display center acquisition process 131.

  The overlap determination process 133 is a process for determining overlap between the display area calculated by the display area calculation process 132 and each enlarged area in the enlarged area list 146.

  The reference texture extraction process 134 specifies a divided area associated with the enlarged area determined to be overlapped by the overlap determination process 133 from the enlarged area list 146, and the texture 500 referred to by the three-dimensional model belonging to the specified divided area. Is extracted from the reference texture list 144.

  The reference texture prefetch process 135 is a process of notifying the acquisition unit 113 of the index extracted by the reference texture extraction process 134. The acquisition unit 113 reads the texture 500 corresponding to the index notified by the reference texture prefetch process 135 from the texture data list 147. The acquisition unit 113 expands the read texture 500 in the drawing memory 150. The texture data list 147 is a list for storing a plurality of textures 500 and is stored in the storage device 300.

  Below, the example of operation | movement (The map display method which concerns on this Embodiment, the process sequence of the program which concerns on this Embodiment) of the map display system 100 is demonstrated.

  FIG. 4 is a latitude / longitude plane projection view showing an example of a three-dimensional model. FIG. 5 is an oblique projection corresponding to FIG.

  4 and 5, the coordinate system used is latitude and longitude coordinates.

  The model storage area indicated by the model storage area data 141 is a rectangular area whose four sides are parallel to the graticule, the southwest end coordinates are (0, 0), and the northeast end coordinates are (10, 10).

  Although not shown, the division number indicated by the area division number data 142 is (longitude direction division number, latitudinal direction division number) = (2, 2).

  FIG. 6 is a table showing an example of the model data list 143.

  In FIG. 6, the five model data A to E stored in the model data list 143 include combinations of vertex data (center of gravity coordinates) and texture names of the three-dimensional models A to E, respectively.

  The three-dimensional model A of the model data A consists of vertices constituting a rectangular parallelepiped, the latitude and longitude of the barycentric coordinates A are (1, 1), and the used texture name is “image A”. The three-dimensional model B of the model data B is composed of vertices constituting a rectangular parallelepiped, the latitude and longitude of the barycentric coordinates B are (6, 1), and the used texture name is “image B”. The three-dimensional model C of the model data C is composed of vertices constituting a rectangular parallelepiped, the latitude / longitude of the barycentric coordinates C is (1, 7), and the used texture name is “image C”. The three-dimensional model D of the model data D is composed of vertices constituting a rectangular parallelepiped, the latitude / longitude of the barycentric coordinates D is (8, 7), and the used texture name is “image D”. The three-dimensional model E of the model data E consists of vertices constituting a rectangular parallelepiped, the latitude and longitude of the barycentric coordinates E are (2, 4), and the used texture name is “image E”.

  Although not shown, the margin indicated by the prefetch determination margin data 145 is (longitude direction margin, latitude direction margin) = (5, 5).

  FIG. 7 is a table showing an example of the texture data list 147.

  In FIG. 7, five textures 500 stored in the texture data list 147 are data of images A to E, respectively. The indexes in the texture data list 147 of the images A to E are “0” to “4”, respectively.

  FIG. 8 is a flowchart showing the procedure of the preprocessing 120. FIG. 9 is a diagram illustrating an example of divided areas. FIG. 10 is a table showing an example of the reference texture list 144. FIG. 11 is a table showing an example of the enlarged area list 146.

  In FIG. 8, first, an area division process 121 is executed.

  In the area division processing 121, the control unit 116 divides the model storage area indicated by the model storage area data 141 in accordance with the area division number data 142. Thereby, the control unit 116 calculates a plurality of divided regions. As a division method, a method of dividing the model storage area by the number of longitude divisions in the east-west direction and the number of divisions by latitude in the north-south direction is used.

  In this example, (longitude direction division number, latitudinal direction division number) = (2, 2). Therefore, as shown in FIG. 9, the control unit 116 divides the model storage area into four divided areas. The four divided areas are divided areas (0,0) = (0,0) to (5,5), divided areas (1,0) = (5,0) to (10,5), and divided areas (0 , 1) = (0, 5) to (5, 10), and divided regions (1, 1) = (5, 5) to (10, 10). The divided area (i, j) is the i-th divided area in the east direction and the j-th divided area in the north direction with respect to the southwest end. When the divided area (i, j) = (k, l) to (m, n), the divided area (i, j) has the southwest end coordinate (k, l) and the northeast end coordinate (m, n). ).

  Next, the model determination process 122 is executed.

  In the model determination process 122, the control unit 116 determines whether each three-dimensional model in the model data list 143 belongs to the divided area for each divided area calculated in the area dividing process 121. Whether the three-dimensional model belongs to the divided area depends on whether the latitude and longitude of the barycentric coordinates of the three-dimensional model are included in the divided area. When the latitude and longitude of the barycentric coordinates are included in the divided area, the control unit 116 determines that the three-dimensional model belongs to the divided area. On the other hand, when the latitude and longitude of the barycentric coordinates are not included in the divided area, the control unit 116 determines that the three-dimensional model does not belong to the divided area.

  In this example, the control unit 116 determines that the three-dimensional models A and E belong to the divided region (0, 0). The control unit 116 performs the same process for other divided regions.

  Next, a reference texture list creation process 123 is executed.

  In the reference texture list creation process 123, the control unit 116 creates (or updates) the reference texture list 144. In the update of the reference texture list 144, the control unit 116 determines the index in the texture data list 147 of the image (that is, the texture 500) referred to by the three-dimensional model determined to belong to the divided area in the model determination process 122, and the divided area. Create a combination with a range definition. The control unit 116 adds the created combination to the end of the reference texture list 144.

  In this example, the three-dimensional models A and E belong to the divided region (0, 0), and images referred to by the three-dimensional models A and E are images A and E, respectively. Therefore, as shown in FIG. 10, the control unit 116 has indexes in the texture data list 147 of “0” and “4”, and the range of the divided areas is (0, 0) to (5, 5). The combination is added to the reference texture list 144. As shown in FIG. 10, the control unit 116 performs the same process for other divided regions.

  Next, an enlarged area calculation process 124 is executed.

  In the enlarged area calculation process 124, the control unit 116 calculates an enlarged area from the divided areas calculated in the area dividing process 121. The enlarged region is obtained by adding the margin indicated by the prefetch determination margin data 145 to the divided region in the outward direction of the region.

  In this example, (longitude direction margin, latitude direction margin) = (5, 5). Therefore, the control unit 116 calculates the range (−5, −5) to (10, 10) of the enlarged area corresponding to the divided area (0, 0). As shown in FIG. 11, the control unit 116 adds the calculated range definition to the enlarged region list 146 together with the definition of the divided region range. As shown in FIG. 11, the control unit 116 performs the same process for other divided regions.

  In FIG. 11, the enlarged area list 146 is data including all the divided area information 601, the enlarged area information 602, and the correspondence information 603 described above.

  FIG. 12 is a flowchart showing the procedure of the real-time process 130. FIG. 13 is a latitude / longitude plane projection view showing an example of the display area. FIG. 14 is an oblique projection corresponding to FIG. FIG. 15 is a diagram illustrating an example of an enlarged region overlapping with the display region.

  In FIG. 12, first, a display center acquisition process 131 is executed.

  In the display center acquisition process 131, the control unit 116 acquires the moved display center coordinates every time the display center coordinates are moved by the user's scroll operation. The display center coordinates are the coordinates of the center (that is, the display center) of the screen (or window) of the display device 200. In this example, the value of the display center coordinates is acquired as latitude and longitude coordinates.

  Next, the display area calculation process 132 is executed.

  In the display area calculation process 132, the control unit 116 calculates the display area of the screen of the display device 200 from the display center coordinates acquired in the display center acquisition process 131. The display area is a part of a three-dimensional map and is displayed on the screen of the display device 200. The display area is calculated by the following formula.

In the formula, an arrow above P _center etc. indicates a position vector. P _center is a position vector of the display center and indicates display center coordinates. P _eye is a position vector of the viewpoint position, and indicates viewpoint position coordinates. U is the upward vector, aspect is the screen width / screen height, and θ is the vertical viewing angle. The viewpoint position, the upward vector, and the vertical viewing angle are parameters that must be set in the three-dimensional overhead view. As the viewpoint position, the upward vector, and the vertical viewing angle, predetermined values are used. Calculate α, β, γ, and δ such that the elevation components (third component) of P _RT , P _RB , P _LT , and P _LB are 0, and substitute α, β, γ, and δ into the upper four equations P _RT , P _RB , P _LT , and P _LB calculated in this way become the upper right, lower right, upper left, and lower left vertex coordinates (that is, coordinates indicating the range of the display area), respectively. The relationship between each parameter and the display area is as shown in FIGS.

  The above formula is an example, and the display area may be calculated by another formula.

  Next, the overlap determination process 133 is executed.

  In the overlap determination process 133, the control unit 116 determines overlap between all the enlarged areas in the enlarged area list 146 and the display area calculated in the display area calculation process 132. As an overlap determination method, a method of determining overlap between two quadrangles can be used. Specifically, a method for determining the intersection of four line segments constituting one rectangle and the four line segments constituting the other rectangle, and four vertices of one rectangle are included in the other rectangle. It can be used in combination with a method for determining whether or not. If at least one line segment intersects the other quadrangular line segment, or if at least one vertex is included in the other quadrangle, the two quadrilaterals overlap.

  Next, a reference texture extraction process 134 is executed.

  In the reference texture extraction process 134, the control unit 116 acquires the definition of the range of the divided area corresponding to the enlarged area determined to overlap with the display area in the overlap determination process 133 from the enlarged area list 146. The control unit 116 extracts an index corresponding to the acquired definition of the range of the divided area from the reference texture list 144.

  For example, as shown in FIG. 15, it is assumed that the enlarged area of the divided area (0, 1) overlaps the display area. In this case, the control unit 116 extracts the range (0, 5) to (5, 10) of the divided region (0, 1) from the enlarged region list 146. The control unit 116 extracts the index “2” corresponding to the range of the extracted divided area (0, 1) from the reference texture list 144.

  Next, a reference texture prefetch process 135 is executed.

  In the reference texture prefetch process 135, the control unit 116 notifies the acquisition unit 113 of the index extracted in the reference texture extraction process 134. The acquisition unit 113 reads the texture 500 corresponding to the notified index from the texture data list 147 into the drawing memory 150.

  For example, assume that the control unit 116 notifies the index “2”. In this case, the acquisition unit 113 reads the image C corresponding to the index “2”.

  In this example, as the model storage area, the range in which the southwest end coordinate is (0, 0) and the northeast end coordinate is (10, 10) is used, but other ranges can be used in the same manner.

  In this example, five three-dimensional models are included in the model storage area, but any number of three-dimensional models may be included in the model storage area.

  In this example, for simplicity, the model storage area is equally divided in the latitude direction and the longitude direction. However, the method for dividing the model storage area can be freely selected. For example, as long as the vertex coordinate value for identifying the divided area is determined, the divided area may be an indefinite polygon. As a polygon overlap determination method, the same method as the quadrangle overlap determination method can be used. That is, a method for determining the intersection of a line segment constituting one polygon and a line segment constituting the other polygon, and a method for determining whether the vertex of one polygon is included in the other polygon Can be used in combination. The polygon enlargement region can be created, for example, by adding a margin in the outward direction to the circumscribed rectangle of the polygon.

  In this example, a latitude / longitude coordinate system is used. However, other types of coordinate systems such as a metric coordinate system can be used as long as the coordinate system can uniquely determine the positional relationship.

  In this example, the barycentric coordinates of the three-dimensional model are used to determine whether the three-dimensional model belongs to the divided area. However, another point in the 3D model can also be used. For example, the northernmost point or the center point of a circumscribed rectangle can be used.

  In this example, the number of divisions defined by the region division number data 142 and the margin defined by the prefetch determination margin data 145 are fixed. However, when the scale on the display screen of the three-dimensional map can be changed, a different division number and margin may be defined for each scale. In this case, every time the scale is changed, the number of divisions and the margin to be applied can be switched. Therefore, the efficiency of prefetching is improved.

  As described above, the map display system 100 according to the present embodiment, when an area obtained by expanding the model storage area by a margin overlaps with the display area, before drawing the 3D model existing in the model storage area, The texture 500 relating to the three-dimensional model is prefetched. Therefore, when the display area reaches the model storage area and it becomes necessary to draw the three-dimensional model, the texture 500 can be displayed immediately.

Embodiment 2. FIG.
In the present embodiment, differences from the first embodiment will be mainly described.

  The configuration of map display system 100 according to the present embodiment is the same as that of the first embodiment shown in FIG.

  The detailed configuration of the map display system 100 is also the same as that of the first embodiment shown in FIG.

  In the present embodiment, the storage unit 115 stores the definition information 600 as in the first embodiment. However, the definition information 600 does not include the enlarged area information 602 and the correspondence information 603.

In the present embodiment, every time the display area in the 3D map display device 200 is changed by the scroll operation received by the input unit 114, the control unit 116 "outside the display area after the change of the 3D map" The “near area” is determined as follows.
(1) The control unit 116 refers to the definition information 600 stored in the storage unit 115.
(2 ′) The control unit 116 determines a margin according to the scroll direction and the scroll speed of the scroll operation received by the input unit 114.
(3 ′) The control unit 116 calculates, for each of the plurality of divided areas, an enlarged area in which the divided area is enlarged by the margin determined in (2 ′), and the enlarged area is a display area after the change of the three-dimensional map. Whether it overlaps with at least a part of. The control unit 116 selects a divided region where the enlarged region overlaps at least a part of the display region after the change of the three-dimensional map from the plurality of divided regions.
(4) The control unit 116 determines the divided region selected in (3 ′) as “a region outside and in the vicinity of the display region after changing the three-dimensional map”.

  As in the first embodiment, the control unit 116 creates the texture 500 for the three-dimensional model of the object existing in the region determined in (4) based on the divided region information 601 of the definition information 600 referenced in (1). Identify. The control unit 116 causes the acquisition unit 113 to acquire the specified texture 500. Thereby, the acquisition unit 113 can prefetch the texture 500 for the three-dimensional model of the object existing in the map area that may be displayed in the future by the user's scroll operation, as in the first embodiment. For this reason, the display part 112 can display the texture 500 immediately, when the map area | region will be displayed by a user's scroll operation.

  In the present embodiment, the control unit 116 determines the shape of the “region outside and near the display region after changing the three-dimensional map” according to the scroll direction of the scroll operation received by the input unit 114. Therefore, the acquiring unit 113 can prefetch the texture 500 for the three-dimensional model of the object existing in the scroll direction more than the texture 500 for the three-dimensional model of the object existing in the direction other than the scroll direction. Therefore, the efficiency of prefetching is improved.

  In the present embodiment, the control unit 116 determines the size of “an area outside and in the vicinity of the display area after the change of the three-dimensional map” according to the scroll speed of the scroll operation received by the input unit 114. . Therefore, the acquisition unit 113 prefetches the texture 500 for the three-dimensional model of the object existing in a wider range if the scroll speed is high, and the three-dimensional model of the object present in the narrower range if the scroll speed is slow. The texture 500 can be prefetched. Therefore, the efficiency of prefetching is improved.

  In the first embodiment, the enlarged area is an area obtained by expanding the divided area by a fixed margin. In contrast, in the present embodiment, as described above, the margin can be dynamically changed according to the scroll direction and the scroll speed.

  FIG. 16 is a block diagram illustrating a processing configuration of the control unit 116.

  In FIG. 16, the processing of the control unit 116 includes pre-processing 120 and real-time processing 130 as in the first embodiment shown in FIG. 3.

  In the following, description of the same processing as in the first embodiment will be omitted.

  In the present embodiment, instead of the prefetch determination margin data 145, the reference margin 171 and the reference speed 172 are stored as part of the definition information 600 by the storage unit 115. Further, instead of the enlarged area list 146, the divided area list 173 is stored by the storage unit 115 as a part of the definition information 600. The divided area list 173 is data indicating a plurality of divided areas calculated by the area dividing process 121.

  In the present embodiment, the preprocess 120 does not include the enlarged area calculation process 124. Instead, the real-time process 130 includes an enlarged area calculation process 163. The real-time process 130 further includes a movement information acquisition process 161 and a margin calculation process 162.

  The movement information acquisition process 161 is a process of calculating the movement speed (that is, scroll speed) and movement direction (that is, scroll direction) of the center of the display area based on the center coordinates acquired by the display center acquisition process 131. .

  The margin calculation process 162 is a process for calculating a margin based on the movement speed and movement direction calculated by the movement information acquisition process 161, and the reference margin 171 and the reference speed 172.

  The enlarged area calculation process 163 is a process for calculating an enlarged area by expanding each divided area calculated by the area dividing process 121 by the margin calculated by the margin calculating process 162. In the overlap determination process 133, the overlap between the enlarged area and the display area calculated by the display area calculation process 132 is determined.

  Below, the example of operation | movement (The map display method which concerns on this Embodiment, the process sequence of the program which concerns on this Embodiment) of the map display system 100 is demonstrated.

  In this example, the three-dimensional model shown in FIGS. 4 and 5, the model data list 143 shown in FIG. 6, and the texture data list 147 shown in FIG. 7 are applied.

  Although not shown, the division number indicated by the area division number data 142 is (longitude direction division number, latitudinal direction division number) = (2, 2).

  The reference margin 171 is “5”, and the reference speed 172 is “2”.

  FIG. 17 is a flowchart showing the procedure of the preprocessing 120. FIG. 18 is a table showing an example of the divided area list 173.

  In FIG. 17, first, an area division process 121 is executed.

  In the area dividing process 121, the control unit 116 calculates a plurality of divided areas as in the example of FIG.

  In this example, (longitude direction division number, latitudinal direction division number) = (2, 2). Therefore, the control unit 116 divides the model storage area into four divided areas as shown in FIG. As shown in FIG. 18, the control unit 116 creates a divided area list 173 indicating the definition of the range of the four divided areas.

  In FIG. 18, a divided area list 173 is data including the divided area information 601 described above.

  Next, the model determination process 122 and the reference texture list creation process 123 are executed in the same manner as in the example of FIG.

  In the reference texture list creation process 123, the control unit 116 creates the reference texture list 144 shown in FIG.

  FIG. 19 is a flowchart showing the procedure of the real-time process 130. FIG. 20 is a diagram illustrating an example of an enlarged region overlapping with the display region.

  In FIG. 19, first, the display center acquisition process 131 and the display area calculation process 132 are executed in the same manner as in the example of FIG.

  Next, the movement information acquisition process 161 is executed.

In the movement information acquisition processing 161, the control unit 116 displays the display center coordinates acquired in the display center acquisition processing 131 of the previous real time processing 130 (ie, before movement), the time of the previous real time processing 130, and the current time (ie, The movement speed and direction are calculated from the display center coordinates acquired in the display center acquisition process 131 of the real time process 130 after the movement and the time of the real time process 130 this time. The moving speed and moving direction are calculated by the following formulas.
Speed = | C _aft −C _bef | / (T _aft −T _bef ) = (√ ((C _aft .x−C _bef .x) ² + (C _aft .y−C _bef .y) ² )) / ( T _aft -T _bef )
Dir = tan ⁻¹ ((C _aft .y−C _bef .y) / (C _aft .x−C _bef .x))

In the equation, Speed is the moving speed, Dir is the moving direction, C _bef is the previous display center coordinate, C _aft is the current display center coordinate, T _bef is the start time of the previous movement information acquisition process 161, and T _aft is the current display center coordinate. This is the start time of the movement information acquisition process 161. The subscript x indicates the longitude coordinate of the vertex, and the subscript y indicates the latitude coordinate of the vertex.

  The above formula is an example, and the moving speed and the moving direction may be calculated by another formula. For example, instead of the start time of the movement information acquisition process 161, another type of time such as an acquisition time of display center coordinates may be used.

  Next, a margin calculation process 162 is executed.

In the margin calculation process 162, the control unit 116 calculates the longitude margin and the latitude direction margin according to the reference margin 171 and the reference speed 172 and the movement speed and movement direction calculated in the movement information acquisition process 161. The longitude direction margin and the latitude direction margin are calculated by the following equations.
LonMargin = Speed / BaseSpeed * BaseMargin * cos (Dir)
LatMargin = Speed / BaseSpeed * BaseMargin * sin (Dir)

  In the formula, LonMargin is a longitude margin, LatMargin is a latitude margin, BaseSpeed is a reference speed 172, and BaseMargin is a reference margin 171.

  For example, as shown in FIG. 20, it is assumed that the display center has moved from (-15, 8) to (-10, 10). Further, it is assumed that the time before the display center is moved is “0” and the time after the display center is moved is “2”. In this example, the reference margin 171 is “5” and the reference speed 172 is “2”. Therefore, in this case, the control unit 116 calculates (longitude direction margin, latitude direction margin) = (6.25, 2.5).

  The above formula is an example, and the margin may be calculated by another formula. Alternatively, instead of using an expression, a table may be prepared in advance that shows a combination of the moving speed and moving direction and the corresponding margin, and the margin may be determined by referring to the values in the table. In this case, calculation of the margin can be omitted, so that the processing can be speeded up.

  Next, an enlarged area calculation process 163 is executed.

  In the enlarged area calculation process 163, the control unit 116 calculates an enlarged area from each of the plurality of divided areas in the divided area list 173. The enlarged area is obtained by adding the margin calculated in the margin calculation process 162 to the outer side of the area.

  In this example, (longitude direction margin, latitude direction margin) = (6.25, 2.5) is calculated in the margin calculation process 162. Therefore, the control unit 116 calculates the range (−6.25, −2.5) to (11.25, 7.5) of the enlarged region corresponding to the divided region (0, 0). The control unit 116 performs the same process for other divided regions.

  Next, the overlap determination process 133 is executed.

  In the overlap determination process 133, the control unit 116 determines overlap between all the enlarged areas calculated in the enlarged area calculation process 163 and the display area calculated in the display area calculation process 132. As the duplication determination method, the method described above can be used.

  Next, a reference texture extraction process 134 is executed.

  In the reference texture extraction process 134, the control unit 116 acquires the definition of the range of the divided area corresponding to the enlarged area determined to overlap with the display area in the overlap determination process 133 from the divided area list 173. The control unit 116 extracts an index corresponding to the acquired definition of the range of the divided area from the reference texture list 144.

  For example, as shown in FIG. 20, it is assumed that the enlarged area of the divided area (0, 1) overlaps with the display area. In this case, the control unit 116 extracts the range (0, 5) to (5, 10) of the divided region (0, 1) from the divided region list 173. The control unit 116 extracts the index “2” corresponding to the range of the extracted divided area (0, 1) from the reference texture list 144.

  Next, the reference texture prefetch process 135 is executed in the same manner as in the example of FIG.

  As described above, the map display system 100 according to the present embodiment sets a large margin in the scroll direction and sets a small margin in the other direction. Therefore, the prefetch frequency of the divided areas in the scroll direction increases, and the prefetch frequency of the divided areas in the other direction decreases. For this reason, the map display system 100 can prefetch preferentially the texture 500 of the divided area that is likely to be displayed in the future by the scroll operation.

  The map display system 100 according to the present embodiment increases the margin amount as the scroll speed increases. Therefore, even when the arrival time by scrolling to the divided area far away from the display area is short, it is possible to prefetch the divided area.

Embodiment 3 FIG.
In the present embodiment, differences from the first embodiment will be mainly described.

  FIG. 21 is a diagram showing a configuration of the map display system 100 according to the present embodiment.

  In FIG. 21, the map display system 100 includes a navigation device 101, a mobile terminal 102, and a server device 103.

  The navigation device 101 is mounted on a vehicle as in the first embodiment.

  The mobile terminal 102 is used by a user (for example, a vehicle driver). The mobile terminal 102 is, for example, a smartphone, a tablet, or a mobile phone.

  The navigation device 101 and the mobile terminal 102 transmit / receive data to / from each other by wired communication or wireless communication.

  The mobile terminal 102 and the server device 103 transmit / receive data to / from each other via the network 104. The network 104 is, for example, a mobile communication network, a WAN (Wide / Area / Network), the Internet, or a combination thereof.

  The navigation device 101 includes the same display device 200 and input device 400 as in the first embodiment.

  In the first embodiment, the navigation device 101 includes the storage device 300, but in the present embodiment, the server device 103 includes the storage device 300. The storage device 300 stores a texture 500 for a three-dimensional model of an object (for example, a building) existing on a three-dimensional map, as in the first embodiment.

  FIG. 22 is a block diagram illustrating a detailed configuration of the map display system 100.

  In FIG. 22, the map display system 100 includes a detection unit 111, a display unit 112, an acquisition unit 113, an input unit 114, a storage unit 115, and a control unit 116, as in the first embodiment. In the present embodiment, the detection unit 111, the display unit 112, the acquisition unit 113, the input unit 114, the storage unit 115, and the control unit 116 are all provided in the mobile terminal 102.

  The detection unit 111 detects the current position of the mobile terminal 102. When mobile terminal 102 is used in a vehicle in which navigation device 101 is mounted, detection unit 111 detects the current position of the vehicle in which display device 200 is mounted, as in the first embodiment. Become. The detection unit 111 detects the current latitude and longitude of the vehicle using, for example, a GPS receiver built in the mobile terminal 102.

  The display unit 112 communicates with the navigation device 101 to display the three-dimensional model of an object (for example, a building) existing in the display area of the three-dimensional map display device 200 with respect to the display device 200 of the navigation device 101. A texture 500 is displayed on a three-dimensional map. When the position detected by the detection unit 111 is present in the display area of the display device 200 of the three-dimensional map, the display unit 112 further displays a mark indicating the position on the display device 200 of the navigation device 101 in a three-dimensional manner. Display on the map.

  The acquiring unit 113 acquires the texture 500 that the display unit 112 displays on the display device 200 from the storage device 300 of the server device 103 by communicating with the server device 103 via the network 104.

  The input unit 114 receives the user's scroll operation via the input device 400 of the navigation device 101 by communicating with the navigation device 101.

  The storage unit 115 stores definition information 600 similar to that in the first embodiment.

  Whenever the display area in the 3D map display device 200 is changed by the scroll operation received by the input unit 114, the control unit 116 changes the "area outside and near the display area after the 3D map change". This is determined in the same manner as in Embodiment 1. The control unit 116 specifies the texture 500 for the three-dimensional model of the object existing in the determined area. The control unit 116 causes the acquisition unit 113 to acquire the specified texture 500. Thereby, the acquisition unit 113 can prefetch the texture 500 for the three-dimensional model of the object existing in the map area that may be displayed in the future by the user's scroll operation. For this reason, the display part 112 can display the texture 500 immediately, when the map area | region will be displayed by a user's scroll operation.

  In the first embodiment, the navigation device 101 prefetches the texture 500 from the storage device 300 into a memory (for example, the drawing memory 150) that can read data faster than the storage device 300. The display is speeded up. On the other hand, as described above, in the present embodiment, the mobile terminal 102 prefetches the texture 500 in the mobile terminal 102 from the storage device 300 of the server apparatus 103 that must read data via the network 104. By doing so, the display speed of the texture 500 is increased.

  In the present embodiment, all parts of the map display system 100 are provided in the mobile terminal 102. However, each part of the map display system 100 can be distributed and provided in the navigation device 101, the mobile terminal 102, and the server device 103. For example, the detection unit 111, the display unit 112, the input unit 114, the storage unit 115, and the control unit 116 may be provided in the navigation device 101, and only the acquisition unit 113 may be provided in the mobile terminal 102.

  In the present embodiment, the map display system 100 includes a navigation device 101, a mobile terminal 102, and a server device 103. However, the map display system 100 may be configured with only the navigation device 101 and the mobile terminal 102. Alternatively, the map display system 100 may be configured only by the navigation device 101 and the server device 103. In this case, the navigation device 101 and the server device 103 transmit / receive data to / from each other via the network 104. The map display system 100 may include a device other than the navigation device 101, the mobile terminal 102, and the server device 103.

  FIG. 23 is a diagram illustrating an example of a hardware configuration of each device (that is, the navigation device 101, the portable terminal 102, and the server device 103) of the map display system 100 according to the first to third embodiments.

  In FIG. 23, each device of the map display system 100 is a computer, and includes hardware such as an output device 910, an input device 920, a storage device 930, and a processing device 940. The hardware is used by each unit of each device of the map display system 100 (what will be described as “˜unit” in the description of the embodiment of the present invention).

  The output device 910 is, for example, a display device such as an LCD (Liquid / Crystal / Display), a printer, or a communication module (communication circuit or the like). The output device 910 is used for outputting (transmitting) data, information, and signals by each unit (“˜unit”). The display device 200 described above corresponds to the output device 910.

  The input device 920 is, for example, a keyboard, a mouse, a touch panel, or a communication module (communication circuit or the like). The input device 920 is used for input (reception) of data, information, and signals by each unit (“˜unit”). The input device 400 described above corresponds to the input device 920.

  The storage device 930 is, for example, a ROM (Read Only Memory), a RAM (Random Access Memory), an HDD, or an SSD. The storage device 930 stores a program 931 and a file 932. The program 931 includes a program for executing processing (function) of each unit (“˜unit”). The file 932 includes data, information, signals (values), and the like that are calculated, processed, read, written, used, input, output, and the like by each unit (“˜unit”). The drawing memory 150 and the storage device 300 described above correspond to the storage device 930.

  The processing device 940 is, for example, a CPU (Central Processing Unit). The processing device 940 is connected to other hardware devices via a bus or the like, and controls those hardware devices. The processing device 940 reads the program 931 from the storage device 930 and executes the program 931. The processing device 940 is used for performing calculation, processing, reading, writing, use, input, output, and the like by each unit (“˜ unit”).

  In the description of the embodiments of the present invention, what is described as “to part” may be “to circuit”, “to device”, and “to device”, and “to step” and “to process”. , “˜procedure”, and “˜processing”. That is, what is described as “˜unit” is realized by software alone, hardware alone, or a combination of software and hardware. The software is stored in the storage device 930 as the program 931. The program 931 causes the computer to function as “˜unit” described in the description of the embodiment of the present invention. Alternatively, the program 931 causes the computer to execute the processing of “˜unit” described in the description of the embodiment of the present invention.

  As mentioned above, although embodiment of this invention was described, you may implement in combination of 2 or more among these embodiment. Alternatively, one of these embodiments may be partially implemented. Alternatively, two or more of these embodiments may be partially combined. In addition, this invention is not limited to these embodiment, A various change is possible as needed.

  100 map display system, 101 navigation device, 102 mobile terminal, 103 server device, 104 network, 111 detection unit, 112 display unit, 113 acquisition unit, 114 input unit, 115 storage unit, 116 control unit, 120 preprocessing, 121 area Division processing, 122 model determination processing, 123 reference texture list creation processing, 124 enlarged region calculation processing, 130 real-time processing, 131 display center acquisition processing, 132 display region calculation processing, 133 overlap determination processing, 134 reference texture extraction processing, 135 reference Texture prefetch processing, 141 model storage area data, 142 area division number data, 143 model data list, 144 reference texture list, 145 prefetch determination margin data, 146 enlarged area list, 147 Sture data list, 150 drawing memory, 161 movement information acquisition process, 162 margin calculation process, 163 enlarged area calculation process, 171 reference margin, 172 reference speed, 173 divided area list, 200 display device, 300 storage device, 400 input device , 500 texture, 600 definition information, 601 divided region information, 602 enlarged region information, 603 correspondence information, 910 output device, 920 input device, 930 storage device, 931 program, 932 file, 940 processing device.

Claims (8)

For a display device that displays a map, a display unit that displays an image of an object existing in a display area in the display device of the map on the map;
An acquisition unit that acquires an image that the display unit displays on the display device from a storage device that stores an image of an object existing on the map;
A storage unit for storing definition information defining a plurality of divided areas into which the map is divided;
An input unit that accepts user operations;
Each time the display area of the map on the display device is changed by the operation received by the input unit , the divided area is expanded from the plurality of divided areas based on the definition information stored by the storage unit. In this case, a divided area that overlaps at least a part of the display area after the change of the map is selected as an area outside and near the display area after the change of the map, and after the change of the map to the acquisition unit A map display system comprising: a control unit that acquires an image of an object existing outside and in a region near the display region. Wherein the input unit, as the operation, to accept any scroll operation,
The control unit, based on the definition information stored by the storage unit, every time the display area of the display device of the map is changed by the scroll operation received by the input unit, from the plurality of divided areas, When the divided area is enlarged by a margin according to the scroll direction of the scroll operation, a divided area that overlaps at least a part of the display area after the change of the map is outside and near the display area after the change of the map. The map display system according to claim 1, wherein the map display system is selected as an area. Wherein the input unit, as the operation, to accept any scroll operation,
The control unit, based on the definition information stored by the storage unit, every time the display area of the display device of the map is changed by the scroll operation received by the input unit, from the plurality of divided areas, When the divided area is enlarged by a margin corresponding to the scroll speed of the scroll operation, a divided area that overlaps at least a part of the display area after the change of the map is outside and near the display area after the change of the map. The map display system according to claim 1, wherein the map display system is selected as an area. The storage unit stores, as the definition information, information that further defines a correspondence relationship between the plurality of divided regions and a plurality of enlarged regions in which the plurality of divided regions are each expanded by a certain margin,
The control unit, based on the definition information stored in the storage unit, every time the display area of the map on the display device is changed, from the plurality of enlarged areas, at least of the display area after the change of the map The enlarged area which overlaps with a part is selected, and the divided area corresponding to the selected enlarged area is selected from the plurality of divided areas as an area outside and near the display area after the change of the map. The map display system described. A detector that detects a position of the vehicle on which the display device is mounted;
The said display part makes the said display apparatus display the mark which shows the said position on the said map, when the position detected by the said detection part exists in the display area in the said display apparatus of the said map. The map display system described in 1.   The map display system according to claim 1, wherein the acquisition unit communicates with a computer including the storage device via a network. The display unit displays on the map an image of an object existing in a display area of the display device of the map with respect to the display device that displays the map,
An acquisition unit acquires an image that the display unit displays on the display device from a storage device that stores an image of an object present on the map;
The input unit accepts user operations,
A definition that defines a plurality of divided areas into which the map is divided, which is stored by the storage unit, every time the display area of the map on the display device is changed by an operation received by the input unit. Based on the information, when the divided area is enlarged from the plurality of divided areas, a divided area that overlaps at least a part of the changed display area of the map is outside and in the vicinity of the changed display area of the map. A map display method for selecting an image area and causing the acquisition unit to acquire an image of an object existing outside and in the vicinity of the display area after the map change. A computer comprising a storage unit for storing definition information defining a plurality of divided areas into which a map is divided,
For a display device that displays the map, a display unit that displays an image of an object existing in a display area in the display device of the map on the map;
An acquisition unit that acquires an image that the display unit displays on the display device from a storage device that stores an image of an object existing on the map;
An input unit that accepts user operations;
Each time the display area of the map on the display device is changed by the operation received by the input unit , the divided area is expanded from the plurality of divided areas based on the definition information stored by the storage unit. In this case, a divided area that overlaps at least a part of the display area after the change of the map is selected as an area outside and near the display area after the change of the map, and after the change of the map to the acquisition unit A program for functioning as a control unit that acquires an image of an object existing outside and near the display area.

Images