JP2008287085A - Map display device, personal digital assistant, and computer program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a map viewing environment comfortable for a map viewer by effectively displaying a map together with multiple pieces of additional information on the same screen. <P>SOLUTION: On a line segment forming one graphic Fc on a screen 100 displaying a map, multiple pieces of additional information 101, 102, 103, 110, 111, 120, 121 are displayed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a map display device, a portable terminal, and a computer program.

2. Description of the Related Art Conventionally, a technique for displaying a map around the position of a terminal on a mobile terminal is known. For example, in the prior art described in Patent Document 1, a map, the terminal location, the direction of the destination, and the distance to the destination are displayed on the display screen of the mobile terminal. In the prior art described in Patent Document 2, the distance from the current location to the destination is displayed by the thickness of the arrow. In the prior art described in Patent Document 3, the distance from the current location is displayed as a concentric circle, and characters and symbols indicating the azimuth are displayed on the circumference.
JP 2003-299136 A JP 2005-30800 A JP 2006-330745 A

  However, in the above-described conventional technology, the technology of effectively displaying a plurality of additional information together with a map on the same screen is insufficient, and it is difficult to provide a comfortable map browsing environment for people who view the map. There's a problem.

  The present invention has been made in consideration of such circumstances, and its purpose is to display a plurality of additional information together with a map on the same screen, thereby making the map viewing environment comfortable for a person viewing the map. A map display device, a portable terminal, and a computer program.

  In order to solve the above problems, the map display device according to the present invention includes display means for displaying a plurality of additional information on a line segment forming one figure on a screen on which a map is displayed. Features.

  The map display device according to the present invention is characterized by comprising azimuth information display position calculation means for calculating a position at which the azimuth of the position of the azimuth display target is displayed on the line segment.

  In the map display device according to the present invention, the azimuth information display position calculation means generates a directional vector Vp21 from the center point P2 of the map display screen toward the azimuth display target position P1 in the latitude / longitude coordinate system. A position P3 having the same longitude as the point P2 and higher than the screen center point P2 is selected, a position S3 on the screen coordinate system corresponding to the position P3 is calculated, and the center point S2 of the map display screen in the screen coordinate system is calculated. A direction vector Vs23 from the position to the position S3 is generated, and an angle Am (rotation angle) formed by the direction vector Vs23 and the orientation of the reference direction of the map drawing result is calculated in the screen coordinate system. In the latitude / longitude coordinate system, the direction vector Vs23 is calculated. A direction vector Vp21 ′ obtained by rotating Vp21 by the rotation angle Am is generated, and the direction of the direction vector Vp21 ′ is obtained. A direction vector Vs21 indicating the same direction as the direction vector Vp21 ′ is generated from the plane center point S2, and an intersection point between the direction vector Vs21 and the figure is calculated, and the intersection point is determined as a display position of the direction information. Features.

  In the map display device according to the present invention, the display means displays a line segment forming the graphic together with the plurality of additional information.

  A portable terminal according to the present invention includes any one of the map display devices described above.

  A computer program according to the present invention is characterized in that a computer realizes a function of displaying a plurality of additional information on a line segment forming one graphic on a screen on which a map is displayed.

  The computer program according to the present invention is characterized in that the computer further realizes a function of calculating a position for displaying the azimuth of the position of the azimuth display target on the line segment.

  In the computer program according to the present invention, the display position calculation function generates a direction vector Vp21 from the center point P2 of the map display screen toward the orientation display target position P1 in the latitude / longitude coordinate system, A position P3 having the same longitude and higher than the screen center point P2 is selected, a position S3 on the screen coordinate system corresponding to the position P3 is calculated, and the position S3 from the center point S2 of the map display screen in the screen coordinate system is calculated. Is generated, and an angle Am (rotation angle) formed by the direction vector Vs23 and the orientation of the reference direction of the map drawing result is calculated in the screen coordinate system, and the direction vector Vp21 is rotated in the latitude / longitude coordinate system. A direction vector Vp21 ′ rotated by an angle Am is generated, and the direction of the direction vector Vp21 ′ is obtained. A direction vector Vs21 indicating the same direction as the direction vector Vp21 ′ is generated from the screen center point S2, an intersection between the direction vector Vs21 and the figure is calculated, and the intersection is determined as a display position of the direction information. Features.

In the computer program according to the present invention, a line segment forming the graphic is also displayed together with the plurality of additional information.
As a result, the map display device described above can be realized using a computer.

  According to the present invention, on a screen on which a map is displayed, by displaying a plurality of additional information on a line segment that forms one figure, a plurality of additional information is displayed with relevance, and thus is visually recognized. It becomes easy to display a plurality of additional information together with a map on the same screen effectively. Thereby, the person who views the map can easily recognize a plurality of additional information together with the map on the same screen, and can enjoy a comfortable map browsing environment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing a hardware configuration of a mobile terminal 1 according to an embodiment of the present invention. In FIG. 1, the mobile terminal 1 includes a CPU (Central Processing Unit) 11, a storage unit 12, a wireless unit 13, a measurement unit 14, an operation unit 15, a display unit 16, a microphone 17, and a speaker 18.

  The CPU 11 realizes various information processing functions (terminal control function, communication function, map display function, guidance (navigation) function for roads, stores, etc.) by executing programs stored in the storage unit 12. The storage unit 12 stores programs executed by the CPU 11 and various data (such as map data and graphic data).

  The wireless unit 13 transmits and receives wireless signals via an antenna and performs voice communication or data communication. The measuring unit 14 is a device (for example, GPS (Global Positioning System)) that acquires position information (latitude, longitude) that indicates the position of the terminal, and a device that acquires information for obtaining a direction in which the terminal is facing. (For example, a geomagnetic sensor for detecting geomagnetism).

  The operation unit 15 has operation keys such as a numeric keypad for inputting a telephone number and various function keys. The operation unit 15 outputs data input by a key operation to the CPU 11. The display unit 16 includes a display panel (for example, a liquid crystal display panel) and a display panel control circuit. The display unit 16 receives display data from the CPU 11 and displays the display data on a screen on the display panel. The microphone 17 outputs the input audio signal to the CPU 11. The speaker 18 outputs an audio signal input from the CPU 11.

  FIG. 2 is a functional block diagram showing a portion related to the map display function in the block configuration in which the functions realized by the CPU 11 shown in FIG. 1 executing the program stored in the storage unit 12 are developed. Hereinafter, each function will be sequentially described.

[Destination setting function]
The destination setting function 21 is a destination set in advance in the map data, a destination set in advance in an application (for example, a navigation program) executed on the terminal, or a destination set by a user operation. The location is acquired and set as display information to be displayed on the map displayed on the screen. When there is a destination on the map displayed on the screen, characters or symbols indicating the destination are displayed at the position of the destination on the map displayed on the screen. On the other hand, when there is no destination on the map displayed on the screen, characters or symbols indicating the direction of the destination are displayed on the screen. A method of displaying characters or symbols indicating the direction of the destination on the screen will be described later.

[Own terminal direction measurement function]
Based on the detection signal of the geomagnetic sensor, the own terminal orientation measurement function 22 is shifted from the north direction in the reference direction of the own terminal (for example, the upper direction of the display surface of the display panel (direction on the image display start side)) Get the angle (indicates how many times it is shifted in which direction). The own terminal direction measurement function 22 calculates the own terminal direction (the direction in which the reference direction of the own terminal is directed) from the acquired angle.

[Own terminal time acquisition function]
The own terminal time acquisition function 23 acquires the time at the own terminal. As this time, the time of the clock built in the terminal itself or the time of the result of performing the time synchronization process with the base station by wireless communication is acquired.

[Local terminal positioning function]
The own terminal position positioning function 24 acquires position information (latitude, longitude) of the own terminal. As this position information, the position information acquired by GPS or the position information of the base station is acquired by wireless communication. In addition, when the own terminal position exists on the map displayed on the screen, characters or symbols indicating the own terminal position are displayed at the own terminal position on the map displayed on the screen. On the other hand, when there is no own terminal position on the map displayed on the screen, characters or symbols indicating the orientation of the own terminal position are displayed on the screen. A method of displaying characters or symbols indicating the orientation of the terminal position on the screen will be described later.

[Map drawing function]
The map drawing function 25 reads the map data of the part to be displayed in the screen display area of the display unit 16 from the storage unit 12 and generates map display data for displaying the read map data on the screen. At this time, the following display conditions are followed.
Display conditions (center position, scale value, rotation angle) preset in map data or application.
Display conditions (center position, scale value, rotation angle) based on user's map display operation (map scrolling, enlargement, reduction, rotation, etc.).
Display conditions (center position, scale value, rotation angle) based on the positioning result of the terminal position or the terminal direction.

[Direction determination function of map drawing result]
The map drawing result orientation determining function 26 calculates the orientation of the reference direction (for example, the upper direction of the display surface of the display panel) of the map display screen displayed by the map drawing function 25. This azimuth calculation method will be described with reference to FIG. FIG. 3 shows a screen coordinate system (XY coordinate system) on the map display screen. The Y-axis direction is the reference direction of the map display screen. In FIG. 3, first, two arbitrary points having the same X coordinate are selected, and each position information (latitude and longitude) of the two points is acquired from the map data. Next, a direction vector connecting the two points is generated. This direction vector coincides with the reference direction of the map display screen. Next, an inclination angle indicating how many times the direction vector deviates from the north direction is calculated, and this inclination angle is set as an azimuth angle of the map drawing result. The north direction can be obtained from the detection signal of the geomagnetic sensor.

[Direction determination function to the destination]
The destination direction determination function 27 calculates the direction of the destination on the map display screen for the destination set as display information by the destination setting function 21. A method for calculating the direction of the destination will be described later.

[Direction determination function to the current location]
The orientation determination function 28 for the current location calculates the orientation of the own terminal position on the map display screen with respect to the own terminal position indicated by the position information (latitude, longitude) of the own terminal acquired by the own terminal position positioning function 24. A method for calculating the orientation of the terminal position will be described later.

[Map orientation determination function]
The map orientation determination function 29 calculates the orientation of the map displayed on the screen (north direction on the map). This azimuth calculation method will be described with reference to FIG. FIG. 4 shows a latitude / longitude coordinate system (longitude-latitude coordinate system) in map data. The latitudinal direction is the north direction. In FIG. 4, first, arbitrary two points having the same longitude coordinate are selected. Next, each position (XY coordinate of the screen coordinate system) on the map display screen of the two points is calculated, and a direction vector connecting the two points on the screen coordinate system is generated. Since the direction of the direction vector coincides with the north direction, the direction of the map displayed on the screen is used. Further, an angle formed by the orientation of the map displayed on the screen and the reference direction of the map display screen is defined as the azimuth angle of the map.

[Sun direction determination function]
The sun direction determination function 30 calculates the sun direction at the terminal time of the terminal position. The azimuth of the sun is calculated using the function based on the latitude, longitude, and own terminal time of the own terminal position by defining in advance a function having position information (latitude, longitude) and time at the position as variables. be able to. Alternatively, approximate orientations may be defined in advance, such as east in the morning (eg, 6 am), south at noon, and west in the evening (eg, 6 pm). The sun direction determination function 30 calculates the sun direction on the map display screen by shifting the sun direction of the calculation result by the azimuth angle of the map drawing result.

[Direction determination function of own terminal]
The direction determining function 31 of the own terminal calculates the direction of the own terminal on the map display screen based on the position information (latitude, longitude) of the own terminal acquired by the own terminal position positioning function 24. A method for calculating the direction of the terminal will be described later.

[Scale value determination function]
The scale value determining function 32 calculates a scale value of the map displayed on the screen (for example, a distance corresponding to the horizontal width of the map display screen). FIG. 5 shows the scale value calculation criteria. In FIG. 5, the distance on the latitude / longitude coordinate system is calculated and used as a scale value for two points on the horizontal and vertical ends of the map display screen, or two determined points on the display screen. .

[Map rotation operation guide information holding function]
The map rotation operation guide information holding function 33 holds map rotation operation guide information in which an operation method for rotating and displaying a map displayed on the screen is expressed. The map rotation operation guide information expresses a rotation display operation method using characters or symbols. For example, an operation key for executing a predetermined rotation operation is expressed by characters or symbols. Moreover, as map rotation operation guide information, an icon may be defined and the rotation operation defined beforehand may be performed by designation | designated of the icon displayed on the display screen.

[Integrated layout / drawing function of display information]
The display information integrated arrangement / drawing function 34 generates additional information display data for displaying a plurality of additional information on a line segment forming one graphic on the screen on which the map is displayed. Furthermore, a line segment forming the graphic may be displayed together with the plurality of additional information.

  The display information integrated arrangement / drawing function 34 synthesizes the additional information display data and the map display data so that the additional information display data is overwritten on the map display data on the screen display. The map display data is generated by the map drawing function 25. The combined display data is sent to the display unit 16. Examples of screen display based on display data after synthesis are shown in FIGS.

  As shown in FIGS. 6 and 7, the additional information display data is displayed so as to overwrite the map display data displayed on the display screen 100. The additional information display data in FIG. 6 displays a plurality of additional information on a line segment forming one circle (figure Fc). The additional information display data in FIG. 7 is for displaying a plurality of additional information on a line segment forming one square (figure Fc). In the examples of FIGS. 6 and 7, as additional information, a character string “front” indicating the direction of the terminal, a character string “destination” indicating the direction of the destination, a character “north” indicating the direction of the map, A character string “sun” indicating the direction of the sun, a character string “current location” indicating the direction of the terminal position, a character string “500 m” indicating the scale value of the map, and a character string “left” indicating map rotation operation guide information Rotation “*” and “Right rotation“ # ”” are displayed. The operation for rotating the map counterclockwise is pressing the “*” key. The operation of rotating the map to the right is pressing the “#” key.

  In the example of FIGS. 6 and 7, the line segment forming the graphic Fc is also displayed together with the plurality of additional information. The center of the figure Fc is arranged at the center of the display screen 100. Graphic data such as a circle and a rectangle is stored in the storage unit 12 in advance.

  If there is a destination on the map displayed on the screen, the additional information display data is displayed so that a character or symbol indicating the destination is displayed at the position of the destination on the screen displayed. Generate. Similarly, when the own terminal position is on the map displayed on the screen, additional information is displayed so that a character or symbol indicating the own terminal position is displayed at the own terminal position on the map displayed on the screen. Generate data.

  In the examples of FIGS. 6 and 7, characters are used as the additional information, but characters or symbols can be used as the additional information. Furthermore, an icon can be used as additional information.

  Next, with reference to FIG. 8 and FIG. 9, a method for calculating the direction of the destination and the terminal position and calculating the position for displaying the direction of the destination and the terminal position on the map display screen will be described. FIG. 8 is a flowchart showing a procedure for calculating the display position of orientation information according to the present embodiment. FIG. 9 is an explanatory diagram for explaining a method for calculating a display position of azimuth information according to the present embodiment. FIG. 9 is shown in the screen coordinate system.

  In FIG. 8, in step SP1, the latitude and longitude of the position P1 of the orientation display target (destination, own terminal position, etc.) are acquired from the map data. In step SP2, the latitude and longitude of the point corresponding to the screen center point S2 (see FIG. 9) on the map displayed on the screen are acquired from the map data. The latitude and longitude associated with the screen center point S2 represent the screen center point P2 on the latitude / longitude coordinate system.

  In step SP3, a direction vector Vp21 from the screen center point P2 to the position P1 is generated in the latitude / longitude coordinate system. In step SP4, in the latitude / longitude coordinate system, a position P3 having the same longitude as the screen center point P2 and higher than the screen center point P2 is selected.

  In step SP5, a position S3 (see FIG. 9) on the screen coordinate system corresponding to the position P3 is calculated. In step SP6, a direction vector Vs23 from the screen center point S2 to the position S3 is generated in the screen coordinate system (see FIG. 9). In step SP7, an angle Am (rotation angle) between the direction vector Vs23 and the reference direction orientation (reference orientation) of the map drawing result is calculated in the screen coordinate system (see FIG. 9).

  In step SP8, a direction vector Vp21 'obtained by rotating the direction vector Vp21 by the rotation angle Am in the latitude / longitude coordinate system is generated, and the direction of the direction vector Vp21' is obtained. In step SP9, a direction vector Vs21 indicating the same direction as the direction vector Vp21 'is generated from the screen center point S2 in the screen coordinate system (see FIG. 9).

  In step SP10, the intersection of the direction vector Vs21 and the figure Fc is calculated in the screen coordinate system, and the intersection is determined as the display position of the azimuth information (see FIG. 9).

  FIG. 10 shows an example of the map display screen according to the present embodiment. In FIG. 10, a map is displayed on the display screen 100. Furthermore, a circle (figure Fc) is displayed so as to overwrite the map. Further, a plurality of additional information is displayed on the line segment forming the circle (figure Fc). The additional information includes a symbol 101 indicating the direction of the position where the terminal is located (own terminal position), a symbol 102 indicating the north direction (map direction) on the map, and a symbol indicating the direction of the sun on the map. 103 and symbols 110 and 111 and symbols 120 and 121 as map rotation operation guide information are displayed. Symbols 110 and 111 indicate that the operation of rotating the map to the left is pressing the “*” key. Symbols 120 and 121 indicate that the operation for rotating the map to the right is pressing the “#” key. In the example of FIG. 10, a symbol 130 indicating the center position of the display screen is also displayed.

  According to this embodiment, on the screen on which the map is displayed, by displaying a plurality of additional information on a line segment that forms a single figure, the plurality of additional information is displayed with relevance, so that it is visually recognized. This makes it easier to display a plurality of additional information together with a map on the same screen. Thereby, the person who views the map can easily recognize a plurality of additional information together with the map on the same screen, and can enjoy a comfortable map browsing environment.

2 is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into a computer system and executed. By doing so, you may perform a map display process. Here, the “computer system” may include an OS and hardware such as peripheral devices.
“Computer-readable recording medium” refers to a flexible disk, a magneto-optical disk, a ROM, a writable nonvolatile memory such as a flash memory, a portable medium such as a DVD (Digital Versatile Disk), and a built-in computer system. A storage device such as a hard disk.

Further, the “computer-readable recording medium” means a volatile memory (for example, DRAM (Dynamic DRAM) in a computer system that becomes a server or a client when a program is transmitted through a network such as the Internet or a communication line such as a telephone line. Random Access Memory)), etc., which hold programs for a certain period of time.
The program may be transmitted from a computer system storing the program in a storage device or the like to another computer system via a transmission medium or by a transmission wave in the transmission medium. Here, the “transmission medium” for transmitting the program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line.
The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, and what is called a difference file (difference program) may be sufficient.

As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the specific structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.
For example, the map data may be stored in advance or may be acquired by communication. For example, a map database that stores map data may be accessed via the Internet, and map data to be used may be acquired from the map database.

  Further, the graphic Fc in which a plurality of additional information is arranged is not limited to the above-described circle or square. Examples of the graphic Fc include a circle, an ellipse, a polygon, a star, and a heart shape. FIG. 11 shows (1) an ellipse, (2) a quadrangle, (3) an octagon, (4) a star, and (5) a heart shape as examples of the figure Fc. For example, if a star shape or a heart shape is used, it is possible to make a pleasant browsing screen especially for women, which is effective.

  Further, whether to display or hide the additional information or the graphic Fc may be controlled by a user operation.

  Further, when any additional information is updated, the display position of the additional information may be updated and displayed again.

  Moreover, you may make it display the azimuth | direction of the position of the other portable terminal acquired by communication as additional information instead of the destination.

  The sun direction may be hidden before sunrise and after sunset. Alternatively, before the sunrise and after the sunset, the moon direction may be displayed instead of the sun direction.

  Further, as additional information, for example, the time in the map area displayed on the screen, the communication sensitivity (the direction in which the radio wave is strong) in the own terminal, the positioning accuracy of the own terminal position, the remaining battery level of the own terminal, the map displayed on the screen Operation guide information for enlargement, reduction, or scrolling, weather information in the map area displayed on the screen, direction of the point of interest such as a disaster spot in the map area displayed on the screen, advertisement in the map area displayed on the screen, map displayed on the screen News information in the area, Yoshikata (direction fortune-telling), direction of point information of the type selected by the user (toilet, shelter, etc.), direction of the nearest various point information (station, etc.), direction of rain clouds at the terminal location , Wind direction at own terminal position, ultraviolet light amount at own terminal position, organism habitat in map area displayed on screen (such as detection results of fish finder) Population density in the screen displayed map area (lot dolphin person in either orientation), (either direction is strong) broadcast wave receiving sensitivity of the terminal position, and advanced of the terminal position thereof.

  The mobile terminal according to the present invention includes, for example, a mobile communication network terminal device (for example, a mobile phone, a mobile phone having a data communication function, a data communication terminal device, etc.) provided by a mobile communication carrier, a PDA (Personal Digital Assistants: personal information devices) and portable personal computers. The present invention can also be realized as an apparatus dedicated to map display.

It is a block diagram which shows the hardware constitutions of the portable terminal 1 which concerns on one Embodiment of this invention. It is a functional block diagram which shows the part which concerns on the map display function of the portable terminal 1 shown in FIG. It is explanatory drawing for demonstrating the direction determination function 26 of the map drawing result shown in FIG. It is explanatory drawing for demonstrating the azimuth | direction determination function 29 of the map shown in FIG. It is explanatory drawing for demonstrating the scale value determination function 32 shown in FIG. It is a structural example of the map display screen which concerns on one Embodiment of this invention. It is a structural example of the map display screen which concerns on one Embodiment of this invention. It is a flowchart which shows the display position calculation procedure of the azimuth | direction information which concerns on one Embodiment of this invention. It is explanatory drawing for demonstrating the display position calculation method of the azimuth | direction information which concerns on one Embodiment of this invention. It is an example of the map display screen which concerns on one Embodiment of this invention. It is an example of the figure which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Portable terminal, 11 ... CPU, 12 ... Memory | storage part, 14 ... Measurement part, 15 ... Operation part, 16 ... Display part, 21 ... Destination setting function, 22 ... Own terminal direction measurement function, 23 ... Own terminal time acquisition Functions 24: Positioning function of own terminal 25: Map drawing function 26: Direction determination function of map drawing result 27: Direction determination function to destination 28: Direction determination function to current location 29: Map direction Determining function, 30 ... Sun azimuth determining function, 31 ... Own terminal azimuth determining function, 32 ... Scale value determining function, 33 ... Map rotation operation guide information holding function, 34 ... Display information integrated arrangement / drawing function, Fc ... Shape

Claims (9)

  A map display device comprising display means for displaying a plurality of additional information on a line segment forming one figure on a screen on which a map is displayed.   2. The map display device according to claim 1, further comprising azimuth information display position calculation means for calculating a position at which the azimuth of the position of the azimuth display target is displayed on the line segment. The azimuth information display position calculating means is
In the latitude / longitude coordinate system, a direction vector Vp21 from the center point P2 of the map display screen toward the orientation display target position P1 is generated, and a position P3 having the same longitude as the screen center point P2 and higher than the screen center point P2 is selected. And
A position S3 on the screen coordinate system corresponding to the position P3 is calculated, and a direction vector Vs23 from the center point S2 of the map display screen toward the position S3 is generated in the screen coordinate system,
In the screen coordinate system, an angle Am (rotation angle) formed by the direction vector Vs23 and the orientation of the reference direction of the map drawing result is calculated,
In the latitude / longitude coordinate system, a direction vector Vp21 ′ obtained by rotating the direction vector Vp21 by the rotation angle Am is generated, and the direction of the direction vector Vp21 ′ is obtained.
In the screen coordinate system, a direction vector Vs21 indicating the same orientation as the orientation of the direction vector Vp21 ′ is generated from the screen center point S2, an intersection of the direction vector Vs21 and the figure is calculated, and the intersection is displayed as a display position of the orientation information. To decide,
The map display device according to claim 2, wherein:   The map display device according to claim 1, wherein the display unit displays a line segment forming the graphic together with the plurality of additional information.   A portable terminal comprising the map display device according to any one of claims 1 to 4.   A computer program for causing a computer to realize a function of displaying a plurality of additional information on a line segment forming one figure on a screen on which a map is displayed.   The computer program according to claim 6, further causing the computer to realize a function of calculating a position at which the azimuth of the position of the azimuth display target is displayed on the line segment. The display position calculation function is
In the latitude / longitude coordinate system, a direction vector Vp21 from the center point P2 of the map display screen toward the orientation display target position P1 is generated, and a position P3 having the same longitude as the screen center point P2 and higher than the screen center point P2 is selected. And
A position S3 on the screen coordinate system corresponding to the position P3 is calculated, and a direction vector Vs23 from the center point S2 of the map display screen toward the position S3 is generated in the screen coordinate system,
In the screen coordinate system, an angle Am (rotation angle) formed by the direction vector Vs23 and the orientation of the reference direction of the map drawing result is calculated,
In the latitude / longitude coordinate system, a direction vector Vp21 ′ obtained by rotating the direction vector Vp21 by the rotation angle Am is generated, and the direction of the direction vector Vp21 ′ is obtained.
In the screen coordinate system, a direction vector Vs21 indicating the same orientation as the orientation of the direction vector Vp21 ′ is generated from the screen center point S2, an intersection of the direction vector Vs21 and the figure is calculated, and the intersection is displayed as a display position of the orientation information. To decide,
The computer program according to claim 7.   7. The computer program according to claim 6, wherein a line segment forming the graphic is also displayed together with the plurality of additional information.

Images