JP6247456B2 - Navigation device and map drawing method - Google Patents

Description

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

  In general, in-vehicle navigation devices display a map image on a display device by acquiring and drawing background data, road data, character / symbol data, and the like stored in a map database. Conventionally, a navigation apparatus in which background data is represented by polygons is known (see, for example, Patent Document 1).

  Background data includes water-based polygons such as seas and lakes, land-use polygons such as forests, fields, fields, and densely populated areas, address polygons that represent administrative boundaries, building polygons that represent buildings, and site polygons that represent facility sites There are various types of shape data. If these shape element points increase, the burden of map drawing processing increases and smooth map display cannot be performed. Therefore, the shape element points are thinned out in the map database according to the performance of each car navigation device. Storing.

JP 2006-58530 A

  By the way, if the number of types of background data increases due to changes over time or addition of new drawing items, the number of shape element points to be drawn increases, so the number of element points that the navigation device can smoothly draw on the map becomes. Until then, it is necessary to create a map database by thinning out shape element points. As a result, it is not a smooth shape close to the curve of the original polygon, but a polygon shape with conspicuous corners, and when displayed as a map, the roughness of the shape becomes very noticeable, and the background There was a problem that the display became unnatural. In particular, when multiple polygons with multiple shapes are displayed on the screen, the lines represented by the shapes are conspicuous, making it difficult to instantly identify the road line that you originally want to check on the map of the navigation device. It will affect the sex.

  The present invention was created in view of the above points, and an object of the present invention is to provide a navigation device and map drawing that can improve display unnaturalness when drawing background data composed of polygons. It is to provide a method.

  In order to solve the above-described problems, a navigation device according to the present invention includes a map data acquisition unit that acquires map data necessary for drawing a background object composed of polygons and other objects, and a background based on the map data. A drawing unit that generates image information corresponding to an object and other objects and stores the image information in a frame memory; and a display processing unit that reads the image information stored in the frame memory and displays a map image on the display device. The means performs blurring processing when generating image information corresponding to the background object.

  The map drawing method of the present invention includes a map data acquisition step for acquiring map data necessary for drawing a background object composed of polygons and other objects, and a background object based on the map data. A map drawing step for generating image information corresponding to the object and storing it in the frame memory by the drawing means, and an operation for reading the image information stored in the frame memory and displaying the map image on the display device. And a display processing step performed by the display processing means. In the drawing step, the drawing means performs blurring processing when generating image information corresponding to the background object.

  Since a blur process is performed when drawing a background composed of polygons, even when using rough polygons with a reduced number of shape element points due to thinning, polygonal corners and straight lines that indicate the outline The contour of the shape does not stand out, and the unnaturalness when drawing the background data can be improved. For this reason, it becomes easy to identify the road line or the like to be originally confirmed, and the visibility of the entire map can be improved.

In addition, the above-described drawing unit performs the blurring process by repeatedly reducing or enlarging the image information corresponding to the background object once or a plurality of times . In addition , it is desirable that the above-described drawing unit synthesizes the image information corresponding to the background object and the image information after reduction / enlargement by α blend processing. This makes it possible to blur the background outline reliably.

  Also, a first work area having the same size as the frame memory described above, storing image information corresponding to the background object or image information after enlargement, and a reduced image smaller than the first work area It is desirable that the blurring process is performed using the second work area that stores information. As described above, by using two work areas having different sizes, it is possible to efficiently perform the blurring process with reduction / enlargement.

Further, the number of repetitions of the above-described reduction / enlargement is changed according to the traveling speed of the vehicle . Further, it is desirable that the number of repetitions is set to a plurality of times when the traveling speed of the vehicle is a predetermined value or less, and the number of repetitions is set to one when the traveling speed of the vehicle exceeds a predetermined value. Further, it is desirable that the number of repetitions is a plurality of times when the vehicle is stopped, and the number of repetitions is one when the vehicle is traveling. This makes it possible to reduce the processing burden caused by blurring when traveling with a large processing load (or during high-speed traveling) by scrolling the map image according to the vehicle position, etc. (Or during low-speed driving), the degree of blurring by blurring processing can be increased to further improve the visibility of the entire map.

It is a figure which shows the detailed structure of the navigation apparatus of one Embodiment. It is a flowchart which shows the operation | movement procedure which performs a blurring process with respect to a background object. FIG. 3 is an explanatory diagram of a drawing state according to the operation procedure shown in FIG. 2. FIG. 3 is an explanatory diagram of a drawing state according to the operation procedure shown in FIG. 2.

  Hereinafter, a navigation device according to an embodiment of the present invention 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 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. Map data includes road data for map matching and route search consisting of road lists, node tables, intersection configuration node lists, intersection net lists, etc., roads, parks, rivers, landmark buildings and facilities on the map screen, etc. It consists of background data for displaying various properties, administrative division names such as municipalities, road names, intersection names, characters such as building names, and character / symbol data for displaying map symbols.

  Of the various data composing the map data, the background data is related to the present invention, and the data structure is not particularly shown. However, the background data includes water-based polygons such as seas and lakes, forests, fields, and fields. A variety of shape data such as a land use polygon such as a densely populated area, an address polygon representing an administrative boundary, a building polygon representing a building, and a site polygon representing a site of a facility are included. In addition, a background object to be blurred is included in an object (background object) as a background image represented by a shape polygon.

  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. 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, a route guidance processing unit 26, and input processing. The 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 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 polygon calculation units 50 and 53, texture processing units 51 and 54, a frame memory 52, work memories 55 and 56, a reduction / enlargement processing unit 57, and an α blend processing unit 58. A character / symbol information drawing unit 59 and an icon drawing unit 60. In this embodiment, it is assumed that the map image to be displayed is composed of a background image, character / symbol information and icons displayed thereon. In addition, the background image includes water systems such as seas and lakes, and land systems such as roads, buildings, and forests. Each component of these areas is represented by a polygon, and a background image is generated by performing a texture mapping process in which a texture image is pasted on each polygon. Also, blur processing is performed on some background objects such as forests. Furthermore, on the background image, character / symbol information such as a place name and a map symbol and an icon image indicating a specific facility instructed to be displayed are superimposed and synthesized to generate a map image.

  The polygon calculation unit 50 calculates vertex coordinates of each polygon constituting the background object. The texture processing unit 51 performs texture mapping processing for pasting a texture image to each polygon based on the calculated vertex coordinates of the polygon. For example, when a terrestrial object representing a forest is included in a part of the background image, the texture processing unit 51 uses a texture image (blue color) that images a forest with respect to a polygon constituting the water-based object. The map image drawing data corresponding to the background image is generated. This map image drawing data is stored in the frame memory 52. The frame memory 52 stores map image drawing data for a plurality of map leaves corresponding to the current display scale. For example, when displaying a map image around the vehicle position, a map generated for a total of 9 sheets of the leaf including the vehicle position and the 8 leafs arranged around the vehicle. Image drawing data is stored.

  When the background image includes a background object to be blurred, the polygon calculation unit 53 calculates the vertex coordinates of the polygons constituting the background object. The texture processing unit 54 performs texture mapping processing for pasting a predetermined texture image to each polygon based on the vertex coordinates of the polygon calculated by the polygon calculation unit 53. The work memory (large) 55 has a work area (first work area) having the same size and storage position as the frame memory 52, and stores drawing data generated by the texture processing unit 54. The working memory (small) 56 has a working area (first number) of 1 / N (the horizontal and vertical number of pixels is 1 / N and N is larger than 2, for example, N = 4) of the frame memory 52. 2), and stores the drawing data after the reduction processing. The reduction / enlargement processing unit 57 performs 1 / N times or 1/2 times image reduction processing and 2 times or N / 2 times image enlargement processing on the drawing data stored in the work memory 55. I do. The α blend processing unit 58 performs α blend processing on the image enlarged by the reduction / enlargement processing unit 57 and the image stored in the frame memory 52 or the work memory 55, and the processing result is displayed in the frame memory 52 or the work. The memory 55 is overwritten.

  The character / symbol information drawing unit 59 draws various character information images such as place names and building names that are displayed superimposed on the map image in the drawing range. The icon drawing unit 60 draws an icon image of a specific facility instructed to be displayed (for example, an icon image having various shapes according to the type of convenience store when the icon display of a convenience store is instructed). These character information image and icon image are superimposed on the map image drawing data corresponding to the background image stored in the frame memory 52.

  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 drawing unit, and the display processing unit 40 corresponds to the display processing unit. Further, the operation of acquiring map data using the map data storage device 3 and the map buffer 10 is the operation of the map data acquisition step, and the drawing process by the map drawing unit 14 (specifically, as shown in FIG. 2 described later). Operation) corresponds to the operation of the drawing step, and the operation of displaying the map image using the display processing unit 40 corresponds to the operation of the display processing step.

  The navigation apparatus of the present embodiment has such a configuration. Next, a rendering process for performing a blurring process on some background objects will be described. FIG. 2 is a flowchart showing an operation procedure for performing the blurring process on the background object. 3 and 4 are explanatory diagrams of a drawing state according to the operation procedure shown in FIG.

  First, the frame memory 52 is initialized with a background texture (step 100). For example, the initialization processing is performed by the texture processing unit 51, and a regular pattern that fills the entire frame memory 52 is used as the background texture.

  Further, the work memory 55 is initialized with the background color (step 104). For example, the initialization processing is performed by the texture processing unit 54, and a color that does not impair the visibility of the image drawn thereon is used as the background color. Next, the polygon calculation unit 53 calculates vertex coordinates of each polygon constituting the background object to be blurred, and the texture processing unit 54 assigns a texture image to each polygon based on the calculated vertex coordinates of the polygon. Perform the texture mapping process to be pasted. In this way, the drawing process corresponding to the background object to be blurred is performed, and the drawing result is written in the work memory 55 (step 106).

  Next, the reduction / enlargement processing unit 57 performs reduction processing for reducing the vertical and horizontal sizes to 1 / N with respect to the drawing data stored in the work memory 55, and the drawing data after the reduction processing is used as the work memory 56. (Step 108). The reduction / enlargement processing unit 57 performs enlargement processing for doubling the vertical and horizontal sizes of the drawing data stored in the work memory 56 and stores the drawing data after the enlargement processing in the work memory 55. (Step 110).

  Next, the reduction / enlargement processing unit 57 determines whether or not the traveling speed of the vehicle is equal to or less than a predetermined value (step 111). This determination is for considering the processing load due to the difference in the scrolling speed of the map image. In the simplest case, it is determined whether or not the vehicle is stopped (in this case, 0 km / h is used as a predetermined value). Determined. If the traveling speed is less than or equal to the predetermined value, an affirmative determination is made in the determination of step 111.

  Next, the reduction / enlargement processing unit 57 performs reduction processing for reducing the vertical and horizontal sizes to ½ with respect to the drawing data stored in the work memory 55, and the drawing data after the reduction processing is used as the work memory 56. (Step 112). The reduction / enlargement processing unit 57 performs an enlargement process for doubling the vertical and horizontal sizes of the drawing data stored in the work memory 56, and the α blend processing unit 58 performs drawing after the enlargement process. Α blend processing is performed using the data and the drawing data stored in the work memory 55 (drawing data stored in step 110), and the work data 55 is overwritten with the drawing data after the α blend processing ( Step 114).

  Next, or when a negative determination is made in the determination of step 111 (when the traveling speed of the vehicle is faster than a predetermined value), the reduction / enlargement processing unit 57 is then stored in the work memory 55. Enlargement processing is performed on the drawing data so that the vertical and horizontal sizes are N / 2 times. The α blend processing unit 58 draws the drawing data after the enlargement processing and the drawing data stored in the frame memory 52 (step 100). The α blend process is performed using the rendering data initialized in step 1 and stored in the position corresponding to the background object to be blurred), and the rendering data after the α blend process is overwritten in the frame memory 52 (Step 116). For example, an α blend process is performed so that the ratio between the drawing data stored in the frame memory 52 and the drawing data after the enlargement process is 8: 2.

  After the blurring process for the background object is completed in this way, the drawing process is performed for other objects (background image objects, characters / symbols, various icons, etc. that are not to be blurred) (step 118).

  As described above, in the navigation device of the present embodiment, when a background composed of polygons is drawn, a specific background object is subjected to blurring processing. Therefore, rough polygons whose number of shape element points is reduced by thinning are used. Even in this case, polygonal corners and linear outlines indicating the outer portion are not conspicuous, and unnaturalness in drawing background data can be improved. For this reason, it becomes easy to identify the road line or the like to be originally confirmed, and the visibility of the entire map can be improved.

  Further, by reducing or enlarging the image information corresponding to the background object, or by repeating the reduction or enlargement a plurality of times, the image information corresponding to the background object and the image after the reduction / enlargement are also obtained. The blurring process is performed by combining the information with the α blend process, and the background contour can be surely blurred. In particular, by using the work memories 55 and 56 having work areas of different sizes, it is possible to efficiently perform blurring processing with reduction / enlargement.

  Further, the number of repetitions of reduction / enlargement is changed according to the traveling speed of the vehicle. Specifically, the number of repetitions is set to 2 when the traveling speed of the vehicle is equal to or less than a predetermined value (desirably, when the speed is 0 km / h), and the number of repetitions is set to 1 when the traveling speed of the vehicle exceeds the predetermined value. I'm trying. This makes it possible to reduce the processing burden caused by blurring when traveling with a large processing load (or during high-speed traveling) by scrolling the map image according to the vehicle position, etc. (Or during low-speed driving), the degree of blurring by blurring processing can be increased to further improve the visibility of the entire map. Further, the number of repetitions “2” when the traveling speed is less than or equal to a predetermined value may be changed to a plurality of times of 3 or more. In this case, the operations in steps 112 and 114 may be repeated as many times as necessary.

  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, the drawing data of the background object is first multiplied by 1 / N and then doubled (in the case of doubling, for example, the enlargement process is performed by repeating the same pixel value twice. Therefore, it is possible to reduce the burden of the enlargement process). For example, it may be multiplied by N and returned to the same size as the original drawing data.

  In the above-described embodiment, the work memories 55 and 56 are provided separately from the frame memory 52. However, a part of the frame memory 52 may be used as the work memories 55 and 56.

  In the above-described embodiment, the case where the blurring process is performed on the background object represented by the polygon has been described. However, the present invention can also be applied to the case where the blurring process is performed on various objects represented by other than the polygon. it can. For example, after a shadow image is generated along the road, blur processing may be performed on the shadow image.

  In the above-described embodiment, the α blend process is performed using the drawing data after the enlargement process and the initialized drawing data in step 116 of FIG. May be omitted, the drawing data after the enlargement process may be overwritten in the frame memory 52. Further, drawing data corresponding to the background object to be blurred is generated using the polygon calculation unit 50 and the texture processing unit 51, and step 116 is performed using the drawing data and the drawing data after the enlargement processing. The α blending process may be performed.

  As described above, according to the present invention, since a blurring process is performed when a background composed of polygons is drawn, even when a rough polygon having a reduced number of shape element points by thinning is used, Polygonal corners and linear outlines indicating the outer portion are not conspicuous, and unnaturalness when drawing background data can be improved.

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, 53 Polygon calculating part 51, 54 Texture processing part 52 Frame memory 55, 56 Work memory 57 Reduction / enlargement processing unit 58 α blend processing unit 59 Character / symbol information drawing unit 60 Icon drawing unit

Claims (6)

Map data acquisition means for acquiring map data necessary for drawing a background object composed of polygons and other objects,
Drawing means for generating image information corresponding to the background object and other objects based on the map data and storing the image information in a frame memory;
Display processing means for reading out image information stored in the frame memory and displaying a map image on a display device;
And the rendering means performs blurring processing by repeatedly reducing or enlarging the image information corresponding to the background object one or more times when generating the image information corresponding to the background object. Yes,
The number of repetitions of the Scaling the navigation device and changes according to the traveling speed of the vehicle. In claim 1 ,
The navigation apparatus characterized in that the drawing means synthesizes image information corresponding to the background object and the image information after the reduction / enlargement by α blend processing. In claim 1 or 2 ,
A first work area having the same size as the frame memory and storing image information corresponding to the background object or image information after enlargement, and image information that is smaller than the first work area and is reduced The blurring process is performed using the second work area that stores the navigation device. In any one of Claims 1-3 ,
A navigation device characterized in that the number of repetitions is set to a plurality of times when the traveling speed of the vehicle is a predetermined value or less, and the number of repetitions is set to one when the traveling speed of the vehicle exceeds a predetermined value. In claim 4 ,
A navigation apparatus, wherein the number of repetitions is set to a plurality of times when the vehicle is stopped, and the number of repetitions is set to one when the vehicle is running. A map data acquisition step for acquiring map data necessary for drawing a background object and other objects composed of polygons by a map data acquisition means;
Based on the map data, a map drawing step for generating an image information corresponding to the background object and other objects and storing it in a frame memory by a drawing means;
A display processing step of performing an operation of reading image information stored in the frame memory and displaying a map image on a display device by a display processing unit;
In the drawing step, the drawing means repeatedly reduces or enlarges the image information corresponding to the background object once or a plurality of times when generating the image information corresponding to the background object. There line blurring processing by,
The map drawing method, wherein the number of repetitions of the reduction / enlargement is changed according to a traveling speed of the vehicle .

Images