JP3012862B2 - Map display system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a map display system for displaying map data in a display area.

[0002]

2. Description of the Related Art Conventionally, when data in a display area is to be displayed on a display from map data, FIG.
As shown in the flow chart of FIG. 1, it is determined whether or not map data is taken out one by one to determine whether or not the map data is present in the display area. If so, the map data is displayed. Was displayed. Figure 1 below
0 will be briefly described.

FIG. 10 is a flowchart for explaining the prior art. In FIG. 10, S41 specifies a display area. In this method, an area to be displayed on the map data is specified by the operator.

In step S42, map data is read in order. S
43 determines whether the map data read in S42 is in the display area. In the case of YES, a message is displayed on the display in S45, and the process proceeds to S45. On the other hand, in the case of NO, S4
Go to 5.

In step S45, it is determined whether all the map data has been read. In the case of YES, the process of displaying all map data when it is present in the display area and hiding it when it is not present has been completed, thus ending the process. On the other hand, N
In the case of O, the process returns to S42 and repeats for the next map data.

[0006]

As described above, in the conventional map display, it is necessary to repeat the process of displaying the map when it exists in the display area and hiding it when it does not exist in all the map data. However, it is difficult to determine which map data exists in the display area, and there is a problem that time is required. For this reason, it is desired that a map is divided in advance into a mesh shape to determine an area (area number) existing for each map data, and that the map data to be displayed can be easily selected at the time of display.

[0007] The present invention solves these problems,
The entire map is divided into meshes and area numbers are assigned,
The area number where each map data exists is obtained and saved as a bit string, and the bit string of the display area and the saved map data bit string are compared at the time of display, and when they match, the target is determined to be displayed and the map is displayed quickly and easily. It is intended to be.

[0008]

FIG. 1 shows a principle book diagram of the present invention. In FIG. 1, the map display system 1
The map data 6 is displayed in the display area. In this case, the map data 6 includes the display area number calculation means 2, the input means 3, and the display means 4.

The display area number calculation means 2 displays the map data 6 in the display area. The bit string 21 is obtained by dividing the entire map into a plurality of parts in the X direction and the Y direction, giving area numbers, and setting existing area numbers.

[0010] The input means 3 receives various inputs from the input device 5. The display means 4 is for displaying map data on the display device 7. The map data 6 is a storage of map data.
1 is created and added in advance.

The display device 7 displays map data and the like.

[0012]

According to the present invention, as shown in FIG. 1, the display area number calculation means 2 sets a bit of an area number existing in a designated display area on a map and generates a bit string in the X and Y directions. 21, the map data 6 of the bit string 21 having only the area number in which the bit is not set is deleted as a display object, and the display means 4 displays the map data 6 of the bit string 21 which is not deleted in the display area. I am trying to do it.

At this time, the display area number calculating means 2 sets the area number where the rectangle including the map data 6 exists and sets the bits based on the bit strings 21 in the X direction and the Y direction stored in advance. The map data 6 of the bit string 21 having only the local area number is deleted as a display object.

The display area number calculating means 2 calculates a bit string 21 in the X direction and the Y direction of the display area,
AND operation is performed on the bit strings 21 in the X direction and the Y direction on a bit-by-bit basis, and the map data 6 of the bit string 21 in which the X direction or the Y direction or both of them are 0 are deleted as display targets.

The bit strings are sorted in ascending or descending order, and are deleted in the order of the bit strings when they are not to be displayed. Accordingly, the entire map is divided into meshes and area numbers are assigned, and the area numbers where the respective map data 6 exist are obtained in advance and stored as bit strings 21. By comparing the bit string 21 of the data 6 with the bit string 21 to remove the non-display target and displaying the map data 6 to be displayed in the display area, it is possible to easily and quickly select and display the map data to be displayed. It becomes possible.

[0016]

Next, the configuration and operation of an embodiment of the present invention will be sequentially described in detail with reference to FIGS.

According to the sequence shown in the flowchart of FIG.
The operation of the configuration of FIG. 1 will be described in detail. In FIG. 2, S
1 calculates the bit string of the display area. This calculates the bit string of the indicated display area in response to the operator indicating the center point and scale of the display area, as described on the right side, and instructing either the upper left or lower right of the display area. (See FIG. 8).

In step S2, map data is read. S3 is
It is determined whether the bit string of the map data (in the unit of line segment) [X direction] read in S2 is 1 in the bit string of the display area. In the case of YES, it is determined that the display target is a candidate for display only in the determination in the X direction, and the process proceeds to S4 to make a determination in the Y direction. On the other hand, in the case of NO, since it is determined that the map data is not a display target, it is determined in S6 that it is not a display target, and the process skips S7 and proceeds to S8.

In step S4, it is determined whether or not the bit string of the map data (unit of line segment) [Y direction] is 1 in the bit string of the display area. In the case of YES, since the determination in the Y direction is also determined to be the display target, the display target is determined in S5, the determined map data is displayed in the display area in S7, and the process proceeds to S8. On the other hand, in the case of NO in S4, it is determined that the image is to be displayed in the X direction, but not in the Y direction. Therefore, it is determined that the image is not to be displayed in S6, and the process skips S7 and proceeds to S8. .

A step S8 decides whether or not all the map data has been read. If YES, the process ends (END). NO
In the case of, the process returns to S2 and is repeated for the next map data.

As described above, the bit string 21 of the designated display area is obtained, and for the bit in which the 1 in the X direction and the Y direction of this bit string is set, 1 is assigned to at least the X direction and the same number in the bit string 21 of the map data 6. When it is determined that one or more stands in the Y direction, it is determined as a display target in S5, and only the map data determined as the display target is displayed in the display area. Thus, only the map data included in the display area can be extracted and displayed, and the display can be quickly performed. The details will be sequentially described below.

FIG. 3 is a flow chart of a bit string creation process for map data according to the present invention. In FIG. 3, S11 reads map data (in units of line segments). In this method, map data shown in FIG. 6A to be described later is fetched as map data in units of line segments on the map. FIG. 6 (a)
Map data has four nodes (nodes a1, a2,
a3 and a4), which are shown in FIG.
This is expressed as map data A.

In step S12, an area number that intersects between the first node (a1) and the next node (a2) is obtained and represented by a bit string. As shown in FIG. 6B described later, this is represented by a bit string 21 by obtaining a region number that intersects a line segment of the first node a1 of the map data A and the next node a2. As a result, the bit string 21 of the area number at which the line connecting the nodes intersects is obtained.

In step S13, it is determined whether or not the line segment ends. In this case, it is determined whether or not all the lines between the nodes have been completed. In the case of YES, the process proceeds to S14. If NO, S12 is repeated for the next node.

In step S14, the bit strings of the entire line segment are ORed to obtain a bit string. As a result, for the map data in units of line segments, a bit string 21 having a rectangular area number of 1 that includes the map data is obtained.

In step S15, the map data is added to the map data (in units of line segments). This corresponds to the bit string 21 obtained in S14 for each line segment.
Is added to the corresponding map data. In S16, it is determined whether or not the entire map data has ended. If YES, the process ends. In the case of NO, the process returns to S11.

As described above, the nodes in the map data extracted in units of line segments on the map and the area numbers intersecting with the line segments connecting the nodes are determined in the X direction and the Y direction.
The X-direction and Y-direction bit strings resulting from the OR operation of these bit strings 21 are added to the map data. As a result, the area number where the map data exists can be immediately determined, and particularly when the map data is displayed in a specific area, the bit string 21 of the map data is used.
And the bit string 21 of the display area to be displayed are logically operated and determined to be present, and it can be determined very quickly and easily whether or not map data exists in the display area.

FIG. 4 is an explanatory diagram of an area code / bit string according to the present invention. FIG. 4A shows an example of an area code. Here, this area number is an example in which the entire map is divided into eight in the X direction and eight in the Y direction for easy understanding. Area numbers 0 to 7 are assigned to the respective divided parts.

FIG. 4B shows a bit string (X direction). The bit string 21 is obtained by associating each part divided into eight in the X direction in FIG. 4A with a bit. As described in the lower part, each bit is set to: 1 if it exists in the area code in the X direction; and 0 if it does not exist in the area code in the X direction. As a result, 1 is set to the bit of the area number where the map data exists, and 0 is set to the bit of the area number where no map data exists.

FIG. 4C shows an example of a bit string. The bit string is composed of an X direction and a Y direction. For example, in the case of map data A in FIG. (See (d) of FIG. 6). This means that the map data A is included in a rectangle including the area numbers 0, 1, 2, 3, 4, 5, and 6 in the X direction and the area numbers 6 and 7 in the Y direction (see FIG. 5). (See map data A).

FIG. 5 is an explanatory diagram of an area code, map data, and a display area according to the present invention. Here, the numbers in the X direction represent the area numbers, and the numbers in the Y direction represent the area numbers. A: Represents map data A, and nodes a1, a2, a3, a
Consists of four.

B: Represents map data B, nodes b1, b
2, b3, b4, and b5. C: Represents map data C, and nodes c1, c2, c3, c
Consists of four. D: Represents map data D, and nodes d1, d2, d3, d
4, d5, d6 and d7. D1, D2, D3, D
Reference numeral 4 denotes an intersection between the display area E and the map data D.

E: Represents a display area E. FIG. 6 is a diagram illustrating the creation of a bit string according to the present invention. This corresponds to the bit strings ((b-1) and (b-2)) of the nodes and the bit strings ((b-3) and (b-4) of the lines connecting the nodes with respect to the map data A on the map shown in FIG. )) And the state of sequentially calculating the entire bit string ((d)).

FIG. 6A shows map data. This is for the map data A in FIG. 5, the total number of nodes is four, the coordinates of the node a1 (a1x, a1y), the coordinates of the node a2 (a2x, a2y), and the coordinates of the node a3. (A3x, a3y), coordinates (a4x, a4y) of the node a4.

FIG. 6B shows a bit string. (B-1) of FIG. 6 shows a bit string of the node a1. Node a
1 is a node a1 of the map data A in FIG. 5, where the area number 0 in the X direction is 1 and the area number 7 in the Y direction is 1, so that the bit string in the X direction and the bit string 0000 in the Y direction as shown in the figure. 0001 1000 0000.

FIG. 6B-2 shows a bit string of the node a2. The node a2 is the node a2 of the map data A in FIG. 5, and the area number 2 in the X direction is 1 and the area number 6 in the Y direction is 1. Therefore, as shown in the figure, a bit string in the X direction 0000 0100 0100 0000.

FIG. 6 (b-3) shows a bit string at the line segment intersection of a1-a2. This corresponds to nodes a1 and a2
Is 1 in the X direction (except for the same area number as the nodes a1 and a2).
As shown below, the bit string in the X direction is 0000 0010 0000 0000 in the Y direction.

(B-4) of FIG. 6 shows (b-1) and (b-
2) shows a bit string obtained by performing an OR operation on (b-3). As a result, a bit string in which the rectangular area number including the node a1 and the node a2 is set to 1 is obtained.

FIG. 6C similarly shows a2-a3, a
The bit string of 3-a4 is obtained. FIG. 6D shows a1-
The bit strings of a2, a2-a3, and a3-a4 are ORed.
Thereby, all the nodes a1, a2,
This means that the bit strings for a3 and a4 are OR-operated, and a rectangular area number including all these nodes can be calculated as a bit string. The result is a bit string in the X direction shown in the figure as a1-a4, and becomes a bit string 0111111111000000 in the Y direction.

In this embodiment, the entire map is divided in the X direction and the Y direction, and the area numbers are respectively assigned (in the embodiment, the area numbers are divided into 8 and the area numbers from 0 to 7 are assigned in the X direction and the Y direction). For the map data existing on the map, the rectangular area number that includes the map data is represented by a bit string. In addition to this, the area that includes the map data is first determined, and then the determined area is determined. A bit string may be created by determining which area number the area corresponds to.

FIG. 7 shows a display explanation flowchart of the present invention. This is to delete the non-display target of the map data and display only the remaining display target map data based on the bit string of the display area. Here, the map data A, B, C, and D in FIG. 5 will be described as an example. FIG. 8 shows the bit strings of the map data A, B, C, and D in FIG.

In FIG. 7, in step S21, a bit string for each line segment is obtained and stored. For example, for the map data A, B, C, and D shown in FIG. 5, a bit string is obtained as shown in FIG. 8 and added to the map data A, B, C, and D and stored.

In step S22, the bit strings are sorted (ascending) in the X direction. Thus, as described below, the order is A → C → D → B. A, C, and D have the same value and are arranged as they are in the storage order, as can be seen with reference to the bit string in FIG. Since B is larger than the other A, C, and D, it is listed last.

S23 is a bit string (X direction) of the display area.
Ask for. For example, in the case of the display area of FIG. 5, a bit string (X direction) of the display area of FIG. 8 is obtained, and when it is displayed in an easily understandable manner, the bit string in the X direction of FIG.

In step S24, items not in the display area are deleted. For example, in the bit string in the X direction in FIG.
For example, regarding the bit string in the X direction of the graphic data A in FIG. 9B, the numbers (area numbers) 2 to 6 are the same and coincide with each other. On the other hand, in the case of the map data B, the bit string in the X direction is 1000 0000 from FIG. 8 and the numbers 2 to 6 are all 0 and it is determined that they are not in the display area. From these results, as described in the lower part, the map data B was deleted, and the rest were A → C →
D.

In step S25, the bit strings are sorted (ascending) in the Y direction. This results in: C → D → A, as described below.

S26 is a bit string (Y direction) of the display area.
Ask for. For example, in the case of the display area of FIG. 5, a bit string (Y direction) of the display area of FIG. 8 is obtained, and when it is displayed in an easily understandable manner, the bit string in the Y direction of FIG.

In step S27, items not in the display area are deleted. For example, among the bit strings in the Y direction in FIG.
For example, with respect to the bit string in the Y direction of the graphic data A in FIG. 9B, the numbers (area numbers) 2 to 4 are set, but there is no match, so there is no match. Turns out to be a target. On the other hand, in the case of the map data D, there is a match from the bit string in the Y direction in (c) of FIG. From these results, as described in the lower part, the map data A and C are deleted, and the rest is D.

At step S28, the remaining map data D to be displayed is displayed.
Is displayed. As described above, when the bit string of the display area has a number (area number) of 1 in the X direction and the Y direction, the display area is set when the bit string of the map data does not have 1 in all of the X and Y directions. And delete it. Then, only the remaining map data to be displayed, in this example, the map data D, is displayed in the display area. In practice, these determinations are made by, for example, ANDing the bit correspondence between the bit strings in the X and Y directions of the display area and the bit strings in the X and Y directions of the map data.
Performs an operation and sets all bits in the X direction or Y direction to 0.
, And when either bit in both the X direction and the Y direction is 1, the map data can be displayed by a simple bit calculation operation. Can be determined whether or not the map data is included in the display area.

FIG. 8 shows map data A, B, C,
D and an example of a bit string of a display area are shown. This shows the map data A, B, C, D and the bit string of the display area on the screen of FIG.

FIG. 9 is a diagram for explaining the determination of the display object according to the present invention. FIG. 9A shows a bit string in which all the bits included in the display area are set. This corresponds to the display area E in FIG.
belongs to.

FIG. 9B shows a bit sequence in the case of A. This is a bit string of the map data A in FIG.
As indicated by the arrow, there is at least one bit of the map data A in the X direction corresponding to the number in which 1 is set in the bit string of the display area. However, when it is determined from the Y direction, there is no one that stands, so it is not a display target and is not displayed as a result.

FIG. 9C shows a bit sequence in the case of D. This is a bit string of the map data D in FIG.
As indicated by the arrow, there is at least one bit of the map data D corresponding to the number in which 1 is set in the bit string of the display area in the X direction. Also, when judging from the Y direction, there is one that stands and is a display target, and is displayed as a result.

[0054]

As described above, according to the present invention,
The entire map is divided into meshes and area numbers are assigned,
The area number where each map data 6 exists is obtained in advance and stored as a bit string 21. At the time of display, the bit string 21 of the display area and the stored bit string 21 of the map data 6 are compared to delete the display object and remove the display object. Since the configuration is adopted in which only the target map data 6 is displayed in the display area, the display target map data can be easily and quickly selected and displayed. That is, based on the bit string 21, only those included in the display area from the map data 6 can be selected by a simple bit-corresponding arithmetic processing, and the selected map data can be displayed on the display area. High-speed display can be realized in the display area of the map data by simple processing.

[Brief description of the drawings]

FIG. 1 is a principle block diagram of the present invention.

FIG. 2 is a flowchart illustrating the operation of the present invention.

FIG. 3 is a flowchart for creating a bit string of map data according to the present invention.

FIG. 4 is an explanatory diagram of an area number / bit string according to the present invention.

FIG. 5 is an explanatory diagram of an area code, map data, and a display area according to the present invention.

FIG. 6 is an explanatory diagram of creation of a bit string according to the present invention.

FIG. 7 is a display explanatory flowchart of the present invention.

FIG. 8 is an example of map data A, B, C, D and a bit string of a display area according to the present invention.

FIG. 9 is an explanatory diagram of determination of a display target according to the present invention.

FIG. 10 is an explanatory flowchart of the related art.

[Explanation of symbols]

 1: Map display system 2: Display area number calculating means 21: Bit string 3: Input means 4: Display means 5: Input device 6: Map data (bit string added) 7: Display device

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields investigated (Int. Cl. ⁷ , DB name) G06T 1/00 G06T 11/00 G06F 3/14-3/153

Claims (4)

(57) [Claims] 1. The map data (6), wherein the whole map is divided into a plurality of parts in the X direction and the Y direction, and area numbers are assigned.
An X-direction and Y-direction bit string (21) stored in advance by setting an area number existing for each, and an X-direction and an X-direction created by setting bits of an area number existing in a designated display area on a map A display area number calculating means (2) for deleting map data (6) of a bit string (21) having only an area number in which no bit is set as a display object based on the Y direction bit string (21); Prepared, map data (6) of bit string (21) not deleted
Is displayed in the display area. 2. An X-direction and a Y-direction bit string (21) which are stored in advance by setting an area number where a rectangle including the map data (6) exists for each map data (6). 2. The method according to claim 1, wherein
The map display system described in. 3. A display area number calculating means (2) comprising: a bit string (21) in the X and Y directions of the display area; and a bit string (2) in the X and Y directions of the map data (6).
2. The method according to claim 1, further comprising: performing an AND operation on each of the bits (1) and (2) in a bit-wise manner, and deleting the map data (6) of the bit string (21) in which the X direction or the Y direction or both of them are all 0 as a display object. Or the map display system according to claim 2. 4. The map display system according to claim 1, wherein the bit sequence is deleted in the order of the bit sequence after being sorted in ascending or descending order when the bit sequence is not to be displayed.