JP2016095137A - Map display device and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a map display device and method capable of preventing discomfort from occurring in a display when using map data for a two-dimensional display to perform a pseudo three-dimensional display.SOLUTION: A navigation device includes a map data storage device 3 for acquiring map data for two-dimensional display, a map buffer 10, a map drawing part 14 for drawing a map image on the basis of the acquired map data, and a display processing part 40 for displaying the map image drawn by the map drawing part 14 in a display device 6. The map data includes data for drawing both a road and shadow arranged in parallel with the road with a line having a fixed thickness, and the map drawing part 14 sets a magnification on a lower side of a screen larger than a magnification on an upper side of the screen, and draws a map image such that a line width corresponding to at least one between the road and the shadow becomes thicker as the line width goes from the upper side of the screen to the lower side of the screen.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a map display device and method for displaying a map image around a vehicle position and the like.

  2. Description of the Related Art Conventionally, a road map display device that converts road map data on a two-dimensional plane into bird's eye view display data and performs pseudo three-dimensional display is known (see, for example, Patent Document 1). In this road map display device, a map is drawn on a display screen using road map data obtained by converting trapezoidal coordinates for perspective view display into rectangular two-dimensional coordinates on a two-dimensional plane. Since it is not necessary to perform perspective transformation processing in consideration of the viewpoint, the processing speed can be increased.

JP 2003-177031 A

  By the way, in the road map display device disclosed in Patent Document 1, when a road and its shadow are expressed by separate lines, and the road and the shadow are drawn side by side, it expands in the horizontal direction toward the front (lower side) of the screen. Therefore, there is a problem in that the line indicating the road and the line indicating the shadow are separated and a gap is generated between them, resulting in an uncomfortable display.

  The present invention was created in view of these points, and the purpose of the present invention is to display a sense of incongruity when performing pseudo three-dimensional display using map data for two-dimensional display. An object of the present invention is to provide a map display device and method that can prevent the above problem.

  In order to solve the above-described problem, a map display device of the present invention draws a map image based on map data acquisition means for acquiring map data for two-dimensional display, and map data acquired by the map data acquisition means. Map display means, and a map display device comprising a display processing means for displaying a map image drawn by the map drawing means on a display device, the map data includes roads and shadows arranged in parallel to the roads. The map drawing means sets the magnification on the lower side of the screen to be larger than the magnification on the upper side of the screen and corresponds to at least one of a road and a shadow. A map image is drawn so that the line width increases from the upper side of the screen to the lower side of the screen.

  The map display method of the present invention includes a map data acquisition unit that acquires map data for two-dimensional display, a map drawing unit that draws a map image based on the map data acquired by the map data acquisition unit, and a map In a map display method in a map display device comprising display processing means for displaying a map image drawn by a drawing means on a display device, each of a road and a shadow arranged in parallel to the road is fixed in the map data. Data for drawing with a line of thickness is included, the map drawing means sets the magnification on the lower side of the screen larger than the magnification on the upper side of the screen, and sets the line width corresponding to at least one of the road and the shadow A map image is drawn so that it becomes thicker as it goes from the upper side of the screen to the lower side of the screen.

  Even when pseudo three-dimensional display (bird's eye view display) is performed using map data for two-dimensional display, the line width corresponding to at least one of roads and shadows goes from the upper side of the screen to the lower side of the screen. Therefore, since the map image is drawn so as to be thick, the line indicating the road and the line indicating the shadow are not separated on the lower side of the screen and a gap is not generated between them, thereby preventing the display from feeling uncomfortable. be able to.

  The map drawing means described above preferably draws a map image on the lower side of the screen, and draws a distant view image showing the sky on the upper side of the screen adjacent to the map image. Thereby, when the map display is performed, it is possible to give a sense of presence of a bird's eye view display.

  Further, it is desirable that the map drawing means described above varies the line width of the road and the extent of increasing the line width from the upper side of the screen toward the lower side of the screen depending on the type of the road. As a result, even when roads with different thicknesses are drawn for each type, the line width can be made suitable for each type, and the gap between the shadows on any type of road Can be eliminated.

  Further, the map image drawing by the map drawing means described above is performed assuming a bird's-eye view display in which the ground is looked down at a predetermined angle from the sky, and the map drawing means has a virtual viewpoint position in the bird's-eye view display on the ground. It is desirable that the closer the magnification is to the lower side of the screen, and the wider the line width of the road on the lower side of the screen. As a result, even when a map image is drawn with the bird's eye view display angle variably set, the road line width suitable for each angle can be obtained, and any angle (viewpoint position) can be obtained. It is possible to eliminate a gap between the shadows.

It is a figure which shows the structure of the navigation apparatus of one Embodiment. It is a figure which shows the relationship between a viewing angle and the map image of a bird's-eye view display. It is a figure which shows roughly the drawing method of the background image contained in the map image of a bird's-eye view display. It is a figure which shows roughly the drawing method of the road in the background image contained in the map image of a bird's-eye view display. It is a flowchart which shows the operation | movement procedure in the case of performing bird's-eye view display using the map data for two-dimensional displays.

  Hereinafter, a navigation device according to an embodiment to which a map display device of the present invention is applied will be described with reference to the drawings.

  FIG. 1 is a diagram illustrating a configuration of a navigation device according to an embodiment. The navigation device shown in FIG. 1 includes a navigation controller 1, a map data storage device 3, an operation unit 4, a vehicle position detection unit 5, a display device 6, and an audio unit 7. This navigation device is mounted on a vehicle.

  The navigation controller 1 implements various functions such as a map image display operation around the own vehicle position, a facility search operation, and a route search / guidance operation by executing a predetermined operation program using a CPU, ROM, RAM, and the like. . The detailed configuration of the navigation controller 1 will be described later.

  The map data storage device 3 is a storage medium that stores map data for two-dimensional display necessary for map display, facility search, route search, and the like and a reading device thereof. The map data storage device 3 stores map data in units of rectangular figure leaves divided into appropriate sizes by longitude and latitude. The map data of each leaf can be specified and read by designating the leaf number.

  This map data is represented by a coordinate set of points (nodes) expressed by longitude and latitude, and a road is formed by connecting two or more nodes, and a portion connecting two nodes is called a link. The map data includes first road data for map matching and route search composed of a road list, a node table, an intersection configuration node list, an intersection net list, etc., and roads and their shadows according to road types, etc. Second road data for drawing in color, background data for displaying various properties such as parks, rivers, landmark buildings and facilities on the map screen, administrative division names such as city names, road names, intersections It consists of character / symbol data for displaying characters such as names, building names, and map symbols. In the present embodiment, simple bitmap data is used as background data in order to simplify processing and reduce map data.

  The map data storage device 3 is realized by a hard disk device or a semiconductor memory, or by a DVD and its reading device. Further, the map data storage device 3 may be replaced with a communication device to acquire map data from an external map distribution server (not shown).

  The operation unit 4 is for receiving user instructions (operations), and includes various operation buttons and operation knobs. In addition, the operation unit 4 includes a touch panel attached to the screen of the display device 6, and the user can directly perform an operation instruction by pointing a part on the screen with a finger or the like. Yes. The vehicle position detection unit 5 includes, for example, a GPS receiver, an orientation sensor, a distance sensor, and the like, detects the vehicle position (longitude, latitude) at a predetermined timing, and outputs a detection result.

  The display device 6 is composed of, for example, an LCD (liquid crystal display device), and is obtained by a map image around the vehicle position, an intersection guide image, or a facility search based on the video signal output from the navigation controller 1. A search result image including the facility and the surrounding parking lot is displayed. For example, the display device 6 is integrated with a housing of a navigation device arranged in the center of the dashboard or on the dashboard. The display device 6 may be separated from the casing of the navigation device and separated from the driver's legible position. The audio unit 7 outputs a guidance voice or the like generated based on the voice signal input from the navigation controller 1 into the vehicle interior.

  Next, a detailed configuration of the navigation controller 1 will be described. As shown in FIG. 1, the navigation controller 1 includes a map buffer 10, a map readout control unit 12, a map drawing unit 14, a vehicle position calculation unit 20, a destination setting unit 22, a route search processing unit 24, and a route guidance processing unit 26. The input processing unit 30 and the display processing unit 40 are included.

  The map buffer 10 temporarily stores map data read from the map data storage device 3. The map reading control unit 12 sends a request for reading a predetermined range of map data in accordance with the vehicle position calculated by the vehicle position calculating unit 20 and the position designated by the user by operating the operation unit 4. Output to. Based on the map data for two-dimensional display stored in the map buffer 10, the map drawing unit 14 performs drawing processing necessary for displaying a map image on the display device 6 to create map image drawing data. Details of the map drawing unit 14 will be described later.

  The vehicle position calculation unit 20 calculates the vehicle position based on the detection data output from the vehicle position detection unit 5, and if the calculated vehicle position is not on the road of the map data, the vehicle position is calculated. Perform map matching processing to correct.

  The destination setting unit 22 sets a destination for route search processing. For example, the destination setting unit 22 searches for a facility that satisfies the search condition specified by the user and sets it as the destination. The route search processing unit 24 searches for a travel route (guidance route) connecting the departure point and the destination (or waypoint) according to a predetermined search condition. The route guidance processing unit 26 creates guidance route drawing data for displaying the guidance route obtained by the search processing by the route search processing unit 24 so as to be superimposed on the map or displaying an enlarged view of the right / left turn intersection. Then, an audio signal such as intersection guidance necessary for guiding the vehicle along the guidance route is generated.

  The input processing unit 30 outputs commands for performing operations corresponding to various operation instructions input from the operation unit 4 to each unit in the navigation controller 1. The display processing unit 40 receives the map image drawing data created by the map drawing unit 14 and displays a predetermined range of map images on the screen of the display device 6 based on the drawing data.

  Next, details of the map drawing unit 14 will be described. As shown in FIG. 1, the map drawing unit 14 includes a background drawing unit 50, a road drawing unit 52, a character / symbol drawing unit 54, a frame memory 56, an angle setting unit 60, and a conversion table storage unit 62.

  The background drawing unit 50 draws a background image of a predetermined range based on the background data included in the map data, and writes it in the frame memory 56.

  The road drawing unit 52 draws a predetermined range of roads (road body) and its shadow image based on the second road data (drawing road data) included in the map data, and overwrites the background image. To the frame memory 56.

  The character / symbol drawing unit 54 draws a predetermined range of characters and symbols based on the character / symbol data included in the map data, and writes it in the frame memory 56 so as to overwrite the background image.

  The map drawing unit 14 according to the present embodiment not only performs two-dimensional display of a map image using map data for two-dimensional display but also pseudo three-dimensional display using the same map data for two-dimensional display. A map image for displaying a bird's eye view can be drawn.

  The angle setting unit 60 sets a viewing angle when performing bird's-eye view display. For example, when one angle is designated from a plurality of angles in accordance with a user instruction (performed using the operation unit 40), the angle setting unit 60 displays the designated angle in a bird's eye view. Set as the viewing angle.

  FIG. 2 is a diagram illustrating a relationship between a viewing angle and a map image displayed in a bird's eye view. FIG. 2A shows a case where the visual field angle (the visual field angle based on the direction perpendicular to the ground) is 10 °, and the background image M1 and the distant view image S1 above the display image are included in the display screen. As shown in FIG. 2, as the viewing angle increases, the viewpoint position approaches the ground and becomes lower.

  FIG. 2B shows a case where the viewing angle is 30 °, and the display screen includes a background image M2 and a distant view image S2 above it. The boundary (horizon) position between the background image M2 and the distant view image S2 is lower than the boundary position when the viewing angle is 10 °.

  FIG. 2C shows a case where the viewing angle is 50 °, and the display screen includes a background image M3 and a distant view image S3 above the background image M3. The boundary position between the background image M3 and the distant view image S3 is further lower than the boundary position when the viewing angle is 30 °.

  FIG. 2D shows a case where the viewing angle is 70 °, and the display screen includes a background image M4 and a distant view image S4 above it. The boundary position between the background image M4 and the distant view image S4 is further lower than the boundary position when the viewing angle is 50 °.

  The above-mentioned distant view images S1, S2, S3, and S4 are drawn by the background drawing unit 50. For example, a distant view image S 1 or the like created in advance is drawn by the drawing unit 50 and stored in the frame memory 56.

  The background images M1, M2, M3, and M4 described above are created by the background drawing unit 50 and the road drawing unit 52. These background images M1 and the like are created by transforming the background data included in the map image for two-dimensional display based on the conversion table stored in the conversion table storage unit 62.

  FIG. 3 is a diagram schematically showing a drawing method of a background image included in a map image displayed in a bird's eye view, and shows the processing contents mainly performed by the background drawing unit 50. In FIG. 3, a rectangle ABCD corresponds to the display screen, and a rectangle AB′C′D corresponds to the background image M <b> 1 or the like when performing bird's eye view display. A trapezoid abcd having a short bottom side and a long top side is a range for reading background data.

  When performing two-dimensional display, the background data corresponding to the rectangle ABCD may be read and written into the frame memory 56. On the other hand, when performing bird's-eye view display, the background data corresponding to the trapezoid abcd is read and the vertices a, b, c, and d are each the vertices A, B ', C', and D of the rectangle AB'C'D. Coordinate conversion is performed so as to correspond to the above and written in the frame memory 56.

  By performing such processing, it is possible to draw a background image M1 or the like that has been subjected to conversion processing in which the magnification on the lower side of the screen is set larger than the magnification on the upper side of the screen for the background image for two-dimensional display. The conversion table 62 described above stores a conversion table including conversion rules for performing conversion so that each vertex of the trapezoid abcd matches each vertex of the rectangle AB′C′D. The conversion table is prepared with different contents for each viewing angle of the bird's eye view display. For example, as the viewing angle increases, the lower side ad of the trapezoid abcd becomes shorter and the magnification near the lower side of the screen increases.

  FIG. 4 is a diagram schematically showing a method of drawing a road in a background image included in a map image displayed in a bird's eye view, and shows the processing contents mainly performed by the road drawing unit 52.

  The road included in the two-dimensional display map image is drawn so that the road main body R1 and the shadow R2 are parallel to each other. Moreover, each of the road body R1 and the shadow R2 is drawn with a line having a constant thickness.

  On the other hand, in the processing for bird's eye view display using the method shown in FIG. 3, the magnification on the lower side of the screen is set larger than the magnification on the upper side of the screen with respect to the background image for two-dimensional display. The distance between the shadow R2 and the shadow R2 increases as it approaches the lower side of the screen, and conventionally, the road main body R1 and the shadow R2 are each drawn with a constant thickness line, so that a gap is generated between them. (FIG. 4A).

  In the present embodiment, in order to avoid such a gap, the road drawing unit 52 does not make the line widths of the road body R1 and the shadow R2 constant, but goes from the upper side of the screen to the lower side of the screen. Are drawn so that each line width becomes thicker (FIG. 4B). When the viewing angle of the bird's eye view display is determined, in the background image M1 or the like, how much each line width of the road body R1 and the shadow R2 is increased in the horizontal direction from the upper side to the lower side of the trapezoid abcd. Since it is known in advance whether or not a gap is generated, the road drawing unit 52 can appropriately change the widths of the road body R1 and the shadow R2 so that no gap is generated for each viewing angle.

  The map data storage device 3 and the map buffer 10 described above correspond to the map data acquisition unit, the map drawing unit 14 corresponds to the map drawing unit, and the display processing unit 40 corresponds to the display processing unit.

  The navigation apparatus according to the present embodiment has such a configuration, and next, an operation when performing bird's-eye view display will be described. FIG. 5 is a flowchart showing an operation procedure when performing bird's eye view display using map data for two-dimensional display. FIG. 5 shows only the operation procedure when a map image around the vehicle position is displayed as a bird's eye view.

  The angle setting unit 60 determines whether bird's-eye view display is instructed (step 100). The user can instruct bird's-eye view display using the operation unit 4, and if this instruction is not made, a negative determination is made, and this determination is repeated.

  Further, when a bird's eye view display is instructed by the user, an affirmative determination is made in the determination of step 100. Next, the angle setting unit 60 sets a viewing angle when performing bird's eye view display in accordance with a user instruction (step 102). For example, one of the four angles shown in FIG. 2 is selected by the user, and this selected angle is set as the viewing angle. The angle may be selected from a number other than four, or an arbitrary angle may be input by the user. Further, the setting of the viewing angle may be performed when the user performs a predetermined operation.

  Next, the background drawing unit 50 draws a distant view image corresponding to the set viewing angle (step 104). For example, as shown in FIG. 2, a distant view image having a different area corresponding to the viewing angle is drawn and written in the frame memory 56.

  Next, the vehicle position calculation unit 20 detects (calculates) the vehicle position (step 106). Further, the background drawing unit 50 reads the conversion table corresponding to the viewing angle from the conversion table storage unit 62, and draws the background image based on the background data in the manner shown in FIG. 3 (step 108). The drawn background image is written into the frame memory 56.

  Next, the road drawing unit 52 draws the image of the road body R1 and the image of the shadow R2 whose line width becomes thicker toward the bottom of the screen in the manner shown in FIG. 4 based on the second road data ( Step 110). The character / symbol drawing unit 54 draws an image of a character or symbol based on the character / symbol data (step 112). The above-described image of the road body R2 and the like and the image of characters and symbols are written in the frame memory 56 so as to overlap the background image. Next, the display processing unit 40 reads out the image (distant view image, background image, road main body R1 and shadow R2 image, character / symbol image) written in the frame memory 56 and displays it on the screen of the display device 6. (Step 114). Thereafter, the process returns to step 106 and the operations after the vehicle position detection are repeated.

  Thus, in the navigation device of this embodiment, even when pseudo three-dimensional display (bird's eye view display) is performed using map data for two-dimensional display, it corresponds to at least one of a road and a shadow. Since the map image is drawn so that the line width increases as it goes from the upper side of the screen to the lower side of the screen, the line indicating the road and the line indicating the shadow are separated from each other on the lower side of the screen. It is possible to prevent the display from feeling uncomfortable.

  In addition, by drawing a map image on the lower side of the screen and drawing a distant view image showing the sky on the upper side of the screen adjacent to the map image, it is possible to give a sense of presence of bird's-eye view display when the map is displayed. it can.

  In addition, the viewing angle of the bird's eye view display can be changed according to the user's instruction. Even in this case, the road line width suitable for each angle can be set, and any angle ( With respect to (viewpoint position), it is possible to eliminate a gap between the shadow and the shadow.

  In addition, this invention is not limited to the said embodiment, A various deformation | transformation implementation is possible within the range of the summary of this invention. For example, in the above-described embodiment, when the bird's-eye view display is performed, the line widths of both the road main body R1 and the shadow R2 become thicker as they approach the lower side of the screen, but either one (preferably the road main body R1 ) May become thicker as it approaches the bottom of the screen.

  Also, when performing the two-dimensional display, if the thickness of the road main body R1 varies depending on the type of road (highway, toll road, national road, prefectural road, etc.), the screen goes from the upper side of the screen to the lower side of the screen. Therefore, the degree of thickening the road line width may be varied depending on the type of road. As a result, even when roads with different thicknesses are drawn for each type, the line width can be made suitable for each type, and the gap between the shadows on any type of road Can be eliminated.

  In the above-described embodiment, the case where the bird's-eye view display is performed in the navigation device has been described. However, the present invention can also be applied to the case where the bird's-eye view display is performed in the mobile terminal device or the personal computer.

  As described above, according to the present invention, even when pseudo three-dimensional display (bird's eye view display) is performed using map data for two-dimensional display, a line corresponding to at least one of a road and a shadow Since the map image is drawn so that the width increases as it goes from the upper side of the screen to the lower side of the screen, a line indicating a road and a line indicating a shadow are separated on the lower side of the screen, and a gap is generated between them. Therefore, it is possible to prevent the display from feeling uncomfortable.

DESCRIPTION OF SYMBOLS 1 Navigation controller 3 Map data storage device 6 Display apparatus 10 Map buffer 12 Map reading control part 14 Map drawing part 20 Vehicle position calculation part 40 Display processing part 50 Background drawing part 52 Road drawing part 54 Character / symbol drawing part 56 Frame memory 60 Angle setting unit 62 Conversion table storage unit

Claims (5)

Map data acquisition means for acquiring map data for two-dimensional display;
Map drawing means for drawing a map image based on the map data acquired by the map data acquisition means;
Display processing means for displaying a map image drawn by the map drawing means on a display device;
In a map display device comprising:
The map data includes data for drawing a road and a shadow arranged parallel to the road with lines of a certain thickness,
The map drawing means sets the magnification on the lower side of the screen to be larger than the magnification on the upper side of the screen, and increases the line width corresponding to at least one of the road and the shadow from the upper side of the screen toward the lower side of the screen. A map display device characterized by drawing a map image on the screen. In claim 1,
The map display device, wherein the map drawing means draws a map image on the lower side of the screen, and draws a distant view image showing the sky on the upper side of the screen adjacent to the map image. In claim 1 or 2,
The map drawing means is characterized in that the road width of the road and the extent to which the line width increases from the upper side of the screen to the lower side of the screen differ depending on the type of the road. . In any one of Claims 1-3,
The drawing of the map image by the map drawing means is performed assuming a bird's eye view display in which the ground is looked down at a predetermined angle from the sky,
The map drawing means sets the magnification on the lower side of the screen to be larger and sets the line width of the road on the lower side of the screen to be thicker as the virtual viewpoint position in the bird's eye view display is closer to the ground. Display device. Map data acquisition means for acquiring map data for two-dimensional display, map drawing means for drawing a map image based on the map data acquired by the map data acquisition means, and a map image drawn by the map drawing means In a map display method in a map display device comprising a display processing means for displaying
The map data includes data for drawing a road and a shadow arranged parallel to the road with lines of a certain thickness,
The map drawing means sets the magnification on the lower side of the screen to be larger than the magnification on the upper side of the screen, and the line width corresponding to at least one of the road and the shadow increases from the upper side of the screen toward the lower side of the screen. A map display method characterized by drawing a map image on the screen.

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