JPH07262356A - Map display system - Google Patents

Abstract

PURPOSE:To speedily and easily display a map as a display object by dividing the map meshwise, finding an area number where respective map data exist, preserving them as a bit sequence, comparing the bit sequence of a display area with the bit sequence of the preserved map data at the time of display and deciding the map as a display object when they are equal to each other. CONSTITUTION:This system is provided with a display area number calculating means 2 for respectively dividing the entire map into plural areas in X and Y directions, applying the area numbers, and erasing map data 6 of the bit sequence equipped with only the area number, to which no bit is set, as data out of the display object based on the bit sequences in the X and Y directions previously stored by setting the area numbers existing every map data 6 and the bit sequences in the X and Y directions prepared by setting the bit of the area numbers existent in the designated display area on the map. Then, the map data 6 of the non-erased bit sequences are displayed in the display area.

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 it is attempted to display data in a display area from map data on a display, FIG.
As shown in the flowchart in Figure 3, each map data is extracted and it is determined whether or not it exists in the display area. If it exists, it is displayed. If it does not exist, it is hidden and repeated for all data. Was displayed. Figure 1 below
The flowchart of 0 will be briefly described.

FIG. 10 shows a flow chart for explaining the prior art. In FIG. 10, S41 specifies the display area. For this, the operator designates and specifies the area to be displayed on the map data.

In step S42, the map data is read in order. S
43 determines whether the map data read in S42 is within the display area. If YES, the image is displayed on the display in S45, and the process proceeds to S45. On the other hand, if 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 processing of displaying all the map data when it exists in the display area and hiding it when it does not exist is ended, so the processing ends. On the other hand, N
In the case of O, the process returns to S42 and is repeated 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 for all map data. However, there is a problem that it is difficult and time-consuming to determine which map data exists in the display area. Therefore, it is desired to divide the map into a mesh shape in advance and obtain an area (regional number) existing for each map data so that the map data to be displayed can be easily selected at the time of display.

The present invention solves these problems.
Divide the whole map into a mesh shape and assign a regional number,
The area number in which each map data exists is found and saved as a bit string, and at the time of display, the bit string of the display area is compared with the saved bit string of the map data, and if they match, it is determined as the display target and the map is displayed quickly and easily. The purpose is to do.

[0008]

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

The display area number calculating 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, assigning area numbers, and setting existing area numbers.

The input means 3 takes in various inputs from the input device 5. The display means 4 displays map data on the display device 7. The map data 6 is the map data saved, and here the bit string 2
1 is created in advance and added.

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 calculating means 2 sets the bit of the area number existing in the designated display area on the map and creates the bit string in the X and Y directions. On the basis of 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 target, and the display means 4 displays the map data 6 of the bit string 21 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 in which the rectangle containing the map data 6 exists, and the bits are set based on the X-direction and Y-direction bit strings 21 stored in advance. The map data 6 of the bit string 21 having only the non-existing area number is deleted from the display target.

Further, the display area number calculation means 2 uses the bit strings 21 in the X and Y directions of the display area and the map data 6.
An AND operation is performed on each of the X-direction and Y-direction bit strings 21 corresponding to each bit, and the map data 6 of the X-direction or Y-direction or the bit string 21 in which all of them are 0 is excluded from the display target.

Further, the bit strings are sorted in ascending or descending order and then deleted in the order of the bit strings when they are not displayed. Therefore, the whole map is divided into meshes and assigned with region numbers, the region numbers in which the respective map data 6 exist are obtained in advance and saved as a bit string 21, and the bit string 21 of the display area and the saved map are displayed. By comparing the bit string 21 of the data 6 and deleting the non-display target and displaying the map data 6 of the display target in the display area, the map data of the display target can be easily and quickly selected and displayed. It will be possible.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the construction and operation of an embodiment of the present invention will be described in detail with reference to FIGS.

According to the order shown in the flow chart 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. As described on the right side, the bit string of the designated display area is calculated in response to the operator designating the center point of the display area and the scale and the upper left / lower right of the display area. (See Figure 8).

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

In step S4, it is determined whether the bit string of the map data (line segment unit) [Y direction] is 1 in the bit string of the display area. In the case of YES, the determination in the Y direction has also been found to be a display target, so it is determined to be a display target 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 was found to be a display target in the X direction, but it was found to be not a display target in the Y direction, and as a result, it is determined that the display target is not the display target in S6, and the process skips S7 and proceeds to S8. .

In step S8, it is determined whether all the map data has been read. If YES, the process ends (END). NO
In the case of, it returns to S2 and repeats for the next map data.

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

FIG. 3 shows a flowchart for creating a bit string of map data according to the present invention. In FIG. 3, S11 reads the map data (line segment unit). This takes in the map data shown in (a) of FIG. 6 which will be described later as map data for each line segment on the map. (A) of this FIG.
In the map data of, the number of nodes is four (nodes a1, a2,
a3 and a4), which is conceptually shown in FIG.
The map data A is expressed as follows.

In S12, the area number intersecting between the head node (a1) and the next node (a2) is obtained and represented by a bit string. This is represented by a bit string 21 by obtaining an area number that intersects the line segment of the head node a1 of the map data A and the next node a2, as shown in FIG. 6B described later. As a result, it is obtained as the bit string 21 of the area number where the line segments connecting the nodes intersect.

In S13, it is determined whether the line segment is the end. This determines whether all the line segments between nodes have been completed. In the case of YES, it progresses to S14. If NO, S12 is repeated for the next node and the space between the nodes.

In S14, the bit string of the entire line segment is ORed to obtain the bit string. As a result, with respect to the map data in units of line segments, the bit string 21 in which the rectangular area number including the map data is 1 is obtained.

S15 is added to the map data (line segment unit). This is the bit string 21 obtained for each line segment in S14.
Is added to the corresponding map data. A step S16 decides whether or not the entire map data has ended. If YES, then end. If NO, the process returns to S11.

As described above, the X-direction and Y-direction of the map and the area number intersecting the line segment connecting the nodes with respect to the map data extracted in line segment units on the map are obtained.
The bit strings in the X direction and the Y direction, which are the result of the OR operation of the bit strings 21, are added to the map data. As a result, it is possible to immediately determine the area number in which the map data exists, and particularly when the map data is displayed in the specific area, the bit string 21
Then, the bit string 21 of the display area to be displayed is logically operated to determine that there is a match, and it can be determined extremely quickly and easily whether or not the map data exists in the display area.

FIG. 4 is an explanatory diagram of the area number / bit string of the present invention. FIG. 4A shows an example of area numbers. This area number shows an example in which the entire map is divided into eight in the X direction and eight in the Y direction for easy understanding. Region 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 of FIG. As described in the lower part, each bit is set to 1 if it exists in the X-direction area number, and 0 if it does not exist in the X-direction area number. As a result, 1 is set in the bit of the area number where the map data exists and 0 is set in the bit of the area number that does not exist.

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

FIG. 5 is an explanatory diagram of the area number, map data and display area of the present invention. Here, the numbers in the X direction represent area numbers, and the numbers in the Y direction represent area numbers. A: represents the map data A, nodes a1, a2, a3, a
It consists of 4.

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

E: represents the display area E. FIG. 6 shows an explanatory diagram of creating a bit string of the present invention. This is the bit string ((b-1), (b-2)) of the node and the bit string ((b-3), (b-4) of the line segment connecting the nodes with respect to the map data A on the map of FIG. )) And an overall bit string ((d)) are sequentially calculated.

FIG. 6A shows map data. This is for the map data A in FIG. 5, where the total number of nodes is 4, the coordinates of the node a1 (a1x, a1y), the coordinates of the node a2 (a2x, a2y), the coordinates of the node a3. (A3x, a3y), coordinates of the node a4 (a4x, a4y) ,.

FIG. 6B shows a bit string. FIG. 6B-1 shows the bit string of the node a1. Node a
1 is the node a1 of the map data A in FIG. 5, and the region number 0 in the X direction is 1 and the region number 7 in the Y direction is 1. Therefore, as shown in the figure, the bit string in the X direction, the bit string in the Y direction, 0000. 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 drawing, the bit string in the X direction and the bit string in the Y direction. It becomes 0000 0100 0100 0000.

FIG. 6B-3 shows a bit string of line segment intersections a1-a2. This is node a1 and node a2
Since the area number that intersects the line segment that connects is 1 in the X direction (excluding the area numbers that are the same as node a1 and node a2),
As shown below, the bit string in the X direction is the bit string in the Y direction 0000 0010 0000 0000.

FIG. 6B-4 shows (b-1) and (b-
2) shows a bit string obtained by ORing (b-3). As a result, a bit string in which the area number of a rectangle including the nodes a1 and a2 is set to 1 is obtained.

Similarly, FIG. 6C shows a2-a3, a
3-A4 bit string is obtained. FIG. 6D shows a1-
The bit strings of a2, a2-a3, and a3-a4 are ORed.
As a result, all the nodes a1, a2 of the map data A,
This means that the OR operation of the bit strings for a3 and a4 was performed, and the rectangular area number including all these nodes could be calculated as the bit string. The result is a bit string in the X direction and a bit string in the Y direction 0111 1111 1100 0000 shown as a1-a4.

In the present embodiment, the entire map is divided into the X and Y directions and the area numbers are respectively given (in the embodiment, 8 areas are given and area numbers 0 to 7 are given to the X and Y directions). However, regarding 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 included in the map data is first obtained and then the relevant area is obtained. A bit string may be created by determining which area number the area corresponds to.

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

In FIG. 7, S21 finds and stores a bit string for each line segment. For example, for the map data A, B, C and D of 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 S22, the bit strings are sorted (ascending order) in the X direction. As a result, as described below, it becomes: A → C → D → B. A, C, and D have the same value and are arranged in the storage order as they are, as can be seen by referring to the bit string in FIG. Since B is larger than the other A, C, and D, it is arranged last.

S23 is a bit string in the display area (X direction)
Ask for. For example, in the case of the display area of FIG. 5, when the bit string (X direction) of the display area of FIG. 8 is obtained and displayed in an easy-to-understand manner, the bit string in the X direction of FIG. 9A is obtained.

In step S24, those not in the display area are deleted. For example, one of the bit strings in the X direction of FIG.
With respect to the numbers with which the numbers stand, for example, with respect to the bit string in the X direction of the graphic data A in FIG. 9B, numbers 2 to 6 of the numbers (regional numbers) stand 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, all the numbers 2 to 6 are 0, and it is determined that they are not in the display area, so they are deleted. From these results, map data B was deleted and the rest was A → C →
It becomes D.

In S25, the bit strings are sorted in the Y direction (ascending order). As a result, as described on the lower side, C → D → A.

S26 is a bit string in the display area (Y direction)
Ask for. For example, in the case of the display area of FIG. 5, when the bit string (Y direction) of the display area of FIG. 8 is obtained and displayed in an easy-to-understand manner, it becomes as shown in the bit string of Y direction of FIG. 9A.

In step S27, those not in the display area are deleted. For example, one of the bit strings in the Y direction in FIG.
, The number (regional number) 2 to 4 of the bit string in the Y direction of the graphic data A in FIG. 9B is set, but there is no coincidence, so deletion is performed. 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 of (c) of FIG. 9, and it is determined that it is the display target. From these results, the map data A and C are deleted and the rest are D, as described in the lower part.

S28 is the remaining map data D to be displayed.
Is displayed. As described above, with respect to the bit strings in the display area, numbers (area numbers) in which 1 is set in the X direction and Y direction, respectively, the display area is displayed when 1 is not set in all of the X direction or the Y direction in the bit string of the map data. Delete as not present in. Then, only the remaining map data to be displayed, in this example, the map data D is displayed in the display area. These determinations are actually performed by, for example, ANDing the bit correspondences 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 all bits in the X or Y direction are 0
It is possible to perform it by a simple bit operation operation of deleting the map data and displaying the map data as the display target when one of the bits in both the X direction and the Y direction is 1, which is extremely simple and fast. It is possible to determine whether or not the map data is included in the display area.

FIG. 8 shows the map data A, B, C of the present invention.
An example of a bit string of D and a display area is shown. This shows the bit strings of the map data A, B, C, D and the display area on the screen of FIG.

FIG. 9 is an explanatory diagram of discrimination of display objects according to the present invention. FIG. 9A shows a bit string in which all the bits included in the display area are set. This is the display area E of FIG.
belongs to.

FIG. 9B shows a bit string in the case of A. This is the bit string of map data A in FIG.
As indicated by the arrow, there is more than one bit in the map data A that has a bit 1 in the X direction, which corresponds to the number in which 1 is set in the bit string in the display area. However, when judged from the Y direction, there is no one with 1, so it is not a display target and is not displayed as a result.

FIG. 9C shows a bit string in the case of D. This is the bit string of the map data D in FIG.
As indicated by the arrow, there is more than one bit of the map data D that is 1 in the X direction, which corresponds to the number in which 1 is set in the bit string of the display area. , Some of them have a value of 1 when judged from the Y direction, which is a display target, and is displayed as a result.

[0054]

As described above, according to the present invention,
Divide the whole map into a mesh shape and assign a regional number,
The area number in which each map data 6 exists is obtained in advance and saved as a bit string 21, and the bit string 21 in the display area is compared with the saved bit string 21 of the map data 6 at the time of display to remove the non-display target and display. Since only the target map data 6 is displayed in the display area, it is possible to easily and quickly select and display the map data to be displayed. That is, based on the bit string 21, only the map data 6 included in the display area can be selected by a simple bit-corresponding arithmetic process, and the selected map data can be displayed in the display area. High-speed display can be realized in the display area of map data by simple processing.

[Brief description of drawings]

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

FIG. 2 is a flowchart explaining 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 area numbers / bit strings according to the present invention.

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

FIG. 6 is an explanatory diagram of creating a bit string of the present invention.

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

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

FIG. 9 is an explanatory diagram of discrimination of display objects according to the present invention.

FIG. 10 is an explanatory flowchart of a conventional technique.

[Explanation of symbols]

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

Claims (4)

[Claims] 1. The entire map is divided into a plurality of parts in the X direction and the Y direction, and area numbers are given to the map data (6).
An X-direction and Y-direction bit string (21) that has been set in advance by setting a region number that exists for each region, and an X-direction that is created by setting the region number bits that exist in a designated display area on the map and A display area number calculating means (2) for deleting the map data (6) of the bit string (21) having only the area number where no bit is set based on the bit string (21) in the Y direction and excluding it. Prepared and not deleted map data (6) of bit string (21)
Is displayed in the display area. 2. An X-direction and Y-direction bit string (21) in which the bit string (21) is stored in advance for each map data (6) by setting an area number of a rectangle containing the map data (6). ) Has been set.
The map display system described in. 3. The display area number calculating means (2) comprises 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).
The map data (6) of the bit string (21) in which the X direction, the Y direction, or both of them are 0 is deleted as an object to be displayed by ANDing each of 1) and 1 with a corresponding bit. Alternatively, the map display system according to claim 2. 4. The map display system according to claim 1, wherein the bit strings are deleted in ascending or descending order in the order of the bit strings when they are not displayed.