KR20040051266A - Geographic information system for client/server-system and the method - Google Patents

Abstract

PURPOSE: A system and a method for providing geographic information on a client/server environment are provided to increase a data processing speed and a map viewing speed by minimizing a transmission capacity of the map data when a request for enlarging, moving, and reducing a map is generated on a vector map search process. CONSTITUTION: A GUI(Graphic User Interface)(131) shows a map image to a user and receives a request item for changing the map. A section extracting component(132) respectively discriminates/produces a overlapped section and an additional section between a present map sector and the map sector displayed by the request. A communication component(133) requests a query for only the produced additional section to an OGC(Open GIS(Geographic Information System) Consortium) data providing server(120) or a geographic information server(110). A coordinates conversion component(134) converts the coordinates between a real and a screen coordinates system of the vector map data. A map display component(135) displays the completed map image to the user by merging the map image of the additional sector and the overlapped section if the map data of the additional section is received.

Description

Geographic information system for client / server-system and the method}

The present invention relates to a system and method for providing geographic information in a client / server environment, and more particularly, in providing geographic information, when a user requests to enlarge, move, or reduce a display map, the map data is divided through a map area division process. The present invention relates to a system and method for providing geographic information in a client / server environment for minimizing the amount of transmission and improving the viewing speed of a map image.

A geographic information system (GIS) is a system that provides geographic or map information required by a user through querying and analyzing spatial data of a relational database.

Such a geographic information system generally collects geographic data from public institutions or geographic information servers, and then converts it into an appropriate map image and provides it to the user.

In GIS system, geographic data is stored and managed in vector or raster format. When using vector format, data is stored in the form of coordinates (X, Y coordinates) and each terrain and features are described as a series of X, Y coordinate points. Can be.

Since the GIS is operated through a computer system and a network, the data size greatly influences the performance of the GIS system.

In other words, in processing data related to basic search for a map in vector form, the processing time increases as the capacity of data increases, and as the load on the server increases, it causes many problems such as delay in response time in providing map services. .

However, in the conventional geographic information system, when a user requests a magnification, reduction, or movement of a display map while searching for a map, the map data of all regions is displayed every time, even though there is an overlapping area with the map data already secured. Since the image is newly received and imaged, there is a problem that the capacity of the processed data becomes large and the network and system are unnecessarily burdened.

Meanwhile, as an improved method of providing geographic information, a method of minimizing retransmission of a map using a cache technology and a vector data compression method for reducing a transmission amount of a network have been proposed.

However, these improved methods of providing geographic information still have some limitations in minimizing data capacity and network transmission.

Accordingly, the present invention is to solve the above-mentioned problems, the object of the present invention is to minimize the data transmission capacity of the map data when the request to enlarge, move, reduce the map frequently occurs in the vector map search process, The present invention provides a system and method for providing geographic information in a client / server environment that can increase processing speed and map viewing speed.

Geographic information providing system of the client / server environment for achieving the object of the present invention, the client system queries the map data from the geographic information server or OGC data providing server and converts it to provide a map image to the user In the geographic information providing system, the client system includes a GUI interface for displaying a map image to a user and accepting a map change request from the user, and a cross between a current display map area and a map area to be displayed by the map change request. An area extraction component for separately calculating an area and an additional area, a communication component for querying the OGC data providing server or the geographic information server for only the calculated additional area and receiving the query result data, and vector map data Actual coordinate system and screen coordinate system When the coordinate transformation component for performing the mutual coordinate transformation and the communication component receives the map data of the additional area, the coordinate conversion component converts to the screen coordinate system through the coordinate conversion component, and then the map image of the additional area and the intersection area already secured. It consists of a map display component that merges the map images of and displays the completed map image to the user.

In addition, a method for providing geographic information in a client / server environment for achieving the object of the present invention, the user request step of obtaining a map change request from the user to show the map image through the GUI interface; An area extraction step of separately calculating the intersection area and the additional area for the current display map area and the map area to be displayed by the map change request; A query request and reception step of querying the OGC data providing server or the geographic information server only for the calculated additional area and receiving the query result data; A coordinate conversion step of converting received map data of the additional area into a screen coordinate system; And a map display step of displaying the completed map image to the user by merging the map image of the coordinate-added additional region with the map image of the intersected region already secured.

1 is an overview of a client / server geographic information system in accordance with the present invention.

Block diagram.

2 is a block diagram of a client system according to the present invention;

3 is a view showing a region extraction method when a user requests a map movement.

Figure 3a is a region extraction diagram when requesting a map movement to the northeast,

3b is an area extraction diagram when requesting a map movement to the southeast.

Figure 3c is a region extraction when the map movement request to the northwest.

Figure 3d is a region extraction diagram when requesting a map movement to the southwest.

Figure 3e is a region extraction diagram when requesting to move the map in the north-west or north-south.

4 shows a method of extracting an intersection area and an additional area when a user requests a map reduction.

Giving drawings.

5 is a flow chart showing a geographic information providing process according to the present invention.

<Description of the symbols for the main parts of the drawings>

110: geographic information server 120: OGC data providing server

130: client system 131: GUI interface

132: region extraction component 133: communication component

134: coordinate transformation component 135: map display component

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is an overall block diagram of a client / server geographic information system according to the present invention.

As shown in FIG. 1, the client / server geographic information system of the present invention largely includes a geographic information server 110, an OGC data providing server 1200, and a client system 130.

The geographic information server 110 is a server device that manages various geospatial data by database and provides the map data at the request of the client system 130.

The geographic information server 110 includes a spatial engine 111 and a spatial database 112 to perform this role.

The spatial engine 111 performs a spatial operation, a spatial data retrieval function, is connected to the client system 130 in a socket manner, and extracts and transmits spatial information and attribute information on map data of a region requested by the client.

The spatial database 112 manages the database by mapping the map data into spatial information and attribute information.

The OGC data providing server 120 is a GIS data provider component capable of reusing various GIS data and ensuring interoperability based on an international standard of the OLE / COM specification proposed by the Open GIS Consortium.

FIG. 2 is a block diagram illustrating the client system 130 in detail, and the client system 130 will be described with reference to FIG. 2.

The client system 130 is a system for providing a geographic information service to a user. The client system 130 obtains map data from the geographic information server 110 through a standard interface of the OGC data providing server 120, and then converts the data. To provide a map-like image to the user system 140.

As shown in FIG. 2, the client system 130 of the present invention includes a GUI interface 131, a map display component 135, an area extraction component 132, a coordinate transformation component 134, and a communication component. 133.

The GUI interface 131 is a graphical user interface, which shows a map image to the user and accepts map change requirements such as zooming in, zooming out, and moving the map from the user when searching the map.

The region extraction component 132 separately calculates the intersection region and the region to be added, for the map region currently displayed and the map region to be newly displayed by the user's request for enlargement, reduction, or movement.

The communication component 133 queries the geographic information server 110 only through the standard interface of the OGC data providing server 120 for the vector spatial data for the additional area calculated by the area extraction component 132. Receive query result data.

The coordinate transformation component 134 is a component that performs mutual coordinate transformation between the actual coordinate system of the vector map data and the screen coordinate system for display on the screen.

That is, the coordinate transformation component 134 converts the calculated additional region into a coordinate system of vector map data so that the communication component 133 can query the map data of the additional region, and convert the query result map data. Conversion to the screen coordinate system allows the map display component 135 to display the map image on the screen.

The map display component 135 processes and outputs map data in a vector form to a user in order to display a map according to a user's request received from the GUI interface 131.

The map display component 135 plays a key role in the client system 130 in association with the area extraction component 132, the coordinate transformation component 134, and the communication component 133.

That is, the map display component 135 checks the user's map search request through the GUI interface 131, and then causes the area extraction component 132 to calculate the necessary additional area according to the request. Coordinate transformation of the additional area to the map data coordinates through the coordinate conversion component 134, and transmits the coordinates of the conversion of the additional area to the communication component 133 to map the map to the geographic information server 110. Allows you to query data.

When the communication component 133 receives the map data, the communication component 133 converts the map data into the screen coordinate system through the coordinate conversion component 134 and then outputs the searched map image requested by the user through the GUI interface 131.

Meanwhile, the user requests to enlarge, reduce or move the map while searching the map through the GUI interface 131. FIG. 3 shows an intersection or additional area in the region extraction component 132 when the user requests a map movement. 3A to 3E illustrate a method of extracting respective regions according to a moving direction.

FIG. 3A illustrates an area classification process for a case where a user requests a map movement to the northeast.

First, the region extraction component 132 extracts an intersection region Z between the current display region and the region to be displayed due to the movement.

Then, calculate and compare the north moving distance X (line segment ei) and the east moving distance Y (line segment fi),

When X <Y, the first rectangular region ebcg and the second rectangular region aehi

When X> = Y, the first rectangular area abhf and the second rectangular area ifcg are selected as additional request areas.

3B illustrates a region classification process for a case where a user requests a map movement to the southeast.

In this case, the intersection area Z between the current display area and the area to be displayed due to the movement is extracted first.

After calculating and comparing the south moving distance X (line segment ei) and the east moving distance Y (line segment fi),

When X <Y, the first rectangular region ebcg and the second rectangular region higd

When X> = Y, the first rectangular area hfcd and the second rectangular area ebfi are selected as additional areas to be newly requested.

FIG. 3C illustrates a map area classification process for a case where a user requests a map movement to the northwest.

Similarly, the intersection Z between the current display area and the area to be displayed due to the movement is first extracted.

And, the north moving distance X (line segment ei), the west moving distance Y (line segment hi) is calculated and compared,

When X <Y, the first rectangular area aegd and the second rectangular area ebfi are defined as

In the case of X> = Y, the first rectangular area abfh and the second rectangular area higd are selected as additional request areas.

FIG. 3D illustrates an area classification process for a case where a user requests a map movement to the southwest.

Similarly, the region extraction component 132 first extracts the intersection region Z between the current display region and the region to be displayed in the southwest movement.

And, the south travel distance X (line segment ei) and the west travel distance Y (line segment hi) is calculated and compared,

If X <Y, the first rectangular region aegd and the second rectangular region ifgg

When X> = Y, the first rectangular area hfcd and the second rectangular area aehi are selected as additional areas to be newly requested.

FIG. 3E illustrates a method of extracting an intersecting area and an additional area for a case where a user requests a map movement to east, west, or north and south.

As shown at the top of FIG. 3E, when the user requests moving east or west (X = 0), the region extraction component 132 selects the intersection region Z between the current display region and the region to be displayed due to the movement. First, the remaining area K except for the intersecting area Z is selected as the additional area to be newly requested.

In addition, as shown at the bottom of FIG. 3E, when the user requests to move south or north (Y = 0), the area extraction component 132 may move between the areas to be displayed due to the south or north movement in the current display area. The intersecting area Z of is extracted first, and the remaining rectangular area K except for the intersecting area Z is selected as the additional area.

On the other hand, Figure 4 is a view showing a method of extracting the additional area when the user requests to reduce the map.

4 illustrates a method of calculating an additional area to be newly requested by the area extraction component 132 when a user requests a map reduction.

As shown in FIG. 4, when the current display map is reduced at a predetermined ratio, the current display area is included in the area to be displayed and becomes an intersection area, and the surrounding area becomes an additional area to be newly requested.

At this time, the peripheral region is divided into four rectangular regions (region P, region Q, region R, region R, and region S) and selected as additional regions, respectively.

5 is a flowchart illustrating a process in which the client system 130 provides a map image at the request of a user.

As shown in FIG. 5, the client system 130 obtains requirements for enlargement, reduction, and movement of the map according to the map search from the user through the GUI interface 131 (S501).

In this case, the map display component 135 determines whether the user's requirement is an enlargement request, a reduction request, or a movement request.

If the request for an enlargement of the map is made, the geographic information server 110 does not require separate map data and enlarges a portion of the current display map area by a predetermined enlargement ratio (S503). The GUI interface 131 Display on the user screen and return to the standby state for the user input (S504).

On the other hand, when the user requests the movement or reduction of the map, an intersection area and an additional query area between the current display area and the area to be displayed are calculated according to the moving direction and the moving distance or the reduction ratio (S505).

The method of calculating the intersection area and the additional area is as described above with reference to FIGS. 3 and 4.

At this time, the data for the already secured cross region is stored in the form of an image on the memory (S506).

In addition, the additional query region is converted into actual map coordinates through the coordinate transformation component 134. (S507)

The communication component 133 requests the OGC data providing server 120 or the geographic information server 110 as a map coordinate value for the additional area to receive the map data for the additional area (S508).

When the map data for the additional area is received, the coordinate conversion component 134 converts the vector map data into screen coordinates and converts it into a map image form (S509).

In addition, the map display component 135 merges the stored cross-section image and the converted additional region image to the corresponding location, and displays the completed map image to the user through the GUI interface 131. (S510)

On the other hand, the method for providing geographic information in the client / server environment according to the present invention, the user request step of obtaining a map change request from the user to show the map image through the GUI interface 131; An area extraction step of separately calculating the intersection area and the additional area for the current display map area and the map area to be displayed by the map change request; A query request and reception step of querying the OGC data providing server 120 or the geographic information server 110 only for the calculated additional area and receiving the query result data; A coordinate conversion step of converting received map data of the additional area into a screen coordinate system; And a map display step of displaying the completed map image to the user by merging the map image of the coordinate-added additional region with the map image of the intersected region already secured.

When the user requests to enlarge the map in the step of acquiring the user request, the client system 130 enlarges the partial region in the current display map region by a predetermined ratio without asking the map data separately, and enlarges the map image to the user. To provide.

When the user requests to move to the northeast, southeast, southwest, or northwest of the map, the area extraction step first extracts an intersection area between the current display map area and the map area to be displayed due to the movement, and then crosses the area to be displayed. The remaining areas except the area are divided into two rectangular areas, and each is selected as an additional area for requesting new map data.

Further, in the region extraction step, if the user requests a map movement to the east, west, south, or north correctly, the intersection region between the current display map region and the map region to be displayed due to the movement is first extracted, and then the display is performed. In the area, select the remaining area except for the intersection area as the additional area to be newly requested.

When the user requests a reduction request for the display map, the current display map area is an intersection area, the surrounding area is divided into four rectangular areas, each of which is selected as an additional area, and a query request is made only for this.

In the present invention as described above, since most of the user's map search patterns are slightly enlarged, reduced, or moved based on the current display area, it is possible to reduce the amount of data to be transmitted through cross-sectional calculation in terms of data processing speed and the like. Significant effects can be expected.

In addition, the present invention can be easily applied to a client performing a search function for a vector map even in a client / server environment.

As described above, a system and method for providing geographic information in a client / server environment according to the present invention improves data processing speed and minimizes data transmission capacity on a network in performing a map search function for a large amount of vector spatial data. The map can be displayed with quick response time for user convenience.

What has been described above is only one embodiment for implementing a system and method for providing geographic information in a client / server environment according to the present invention, and the present invention is not limited to the above-described embodiment, and the scope of the claims Without departing from the gist of the present invention, any person of ordinary skill in the art will have the technical spirit of the present invention to the extent that various modifications can be made.

Claims (14)

In the geographic information providing system for providing the map image to the user by the client system to collect the map data from the geographic information server or OGC data providing server and converts the map data, The client system, GUI interface that shows the map image to the user and accepts the map change request from the user. An area extraction component for separately calculating the intersection area and the additional area for the current display map area and the map area to be displayed by the map change request; A communication component for querying the OGC data providing server or the geographic information server only for the calculated additional area and receiving the query result data; A coordinate transformation component for performing mutual coordinate transformation between the actual coordinate system of the vector map data and the screen coordinate system; When the communication component receives the map data of the additional area, the coordinate conversion component converts the screen data into a screen coordinate system, and then merges the map image of the additional area with the map image of the intersected area. Geographic information providing system of the client / server environment, characterized in that consisting of a map display component to display to. The method of claim 1, wherein when the user requests to enlarge the map, the map display component provides the user with an enlarged map image by enlarging a portion of the area of the current display map area at a predetermined rate without requesting the query data separately. Geographic information providing system of the client / server environment, characterized in that. The method of claim 1, wherein the region extraction component first extracts an intersection region between the current display map region and the map region to be displayed due to the movement when the user requests to move to the northeast, southeast, southwest, or northwest side of the map. And dividing the remaining areas excluding the intersecting area into two rectangular areas in the area to be displayed and selecting each of them as an additional area for requesting map data. According to claim 3, Wherein the area extraction component, when the user requests to move in the north-east direction of the map, in extracting the two additional areas, and calculates and compares the north moving distance X and the east moving distance Y, In the case of X <Y, the first additional area, which is a rectangular area of each side of the east distance and the north-south distance of the area to be displayed, and the rectangular area of each side of the north-west distance and the east-west distance of the intersection area, Extract the second additional area, In the case of X> = Y, the first additional area, which is a rectangular area of each side of the north moving distance and the east-west distance of the area to be displayed, and the rectangular area of which the north and south distances of the east moving distance and the intersecting area are each side, Geographic information providing system of the client / server environment, characterized in that for extracting the second additional area. According to claim 3, Wherein the area extraction component, when the user requests to move in the southeast direction of the map, in extracting the two additional areas, the south moving distance X and the east moving distance Y calculated, compared, In the case of X <Y, the first additional area, which is a rectangular area of each side of the east moving distance and the north-south distance of the area to be displayed, and the rectangular area of each side of the east-west distance of the south moving distance and the intersection area, Extract the second additional area, In the case of X> = Y, the first additional area, which is a rectangular area of each side of the south moving distance and the east-west distance of the area to be displayed, and the rectangular area of each side of the north-south distance of the east moving distance and the intersection area, Geographic information providing system of the client / server environment, characterized in that for extracting the second additional area. According to claim 3, Wherein the area extraction component, when the user requests to move in the southwest direction of the map, in the extraction of the two additional areas, the south travel distance X and the west travel distance Y calculated, compared, In the case of X <Y, the first additional area which is a rectangular area each side of the west movement distance and the north-south distance of the area to be displayed, and the rectangular area which each side is the east-west distance of the south movement distance and the intersection area Extract the second additional area, In the case of X> = Y, the first additional area, which is a rectangular area of each side of the south moving distance and the east-west distance of the area to be displayed, and the rectangular area of which the north and south distances of the west moving distance and the intersecting area are each side, Geographic information providing system of the client / server environment, characterized in that for extracting the second additional area. According to claim 3, wherein the area extraction component, when the user requests to move in the northwest direction of the map, in the extraction of the two additional areas, the north moving distance X and the west movement distance Y calculated, compared, In the case of X <Y, the first additional area, which is a rectangular area having the west travel distance and the north-south distance of the area to be displayed on each side, and the rectangular area having the north-west distance and the east-west distance of the intersection area on each side, Extract the second additional area, In the case of X> = Y, the first additional area, which is a rectangular area having each side of the north-west distance and the east-west distance of the area to be displayed, and the rectangular area having the north-south distance of the west moving distance and the intersection area, respectively Geographic information providing system of the client / server environment, characterized in that for extracting the second additional area. The method of claim 1, wherein the region extraction component first extracts an intersection region between the current display map region and the map region to be displayed due to the movement when the user accurately requests a map movement to east, west, south, or north. And selecting the remaining area of the displayed area except for the crossing area as an additional request area. The method of claim 1, wherein when the user requests to reduce the display map, the area extraction component uses the current display map area as an intersection area and divides the surrounding area into four rectangular areas, each of which is an additional area. Geographic information providing system of the client / server environment, characterized in that the selection. Obtaining a user request for showing a map image to the user through the GUI interface and accepting a map change request from the user; An area extraction step of separately calculating the intersection area and the additional area for the current display map area and the map area to be displayed by the map change request; A query request and reception step of querying the OGC data providing server or the geographic information server only for the calculated additional area and receiving the query result data; A coordinate conversion step of converting received map data of the additional area into a screen coordinate system; And And a map display step of displaying the completed map image to the user by merging the map image of the coordinate region with the coordinate region of the additional region. The method of claim 10, wherein when the user requests to enlarge the map, the map display step provides an enlarged map image to the user by enlarging a partial region in a current display map region at a predetermined rate without requesting the map data separately. Method for providing geographic information in a client / server environment, characterized in that. The method of claim 10, wherein the step of extracting the area comprises first extracting an intersection area between the current display map area and the map area to be displayed due to the movement when the user requests to move to the northeast, southeast, southwest, or northwest side of the map. And dividing the remaining areas excluding the intersecting area into two rectangular areas in the area to be displayed and selecting each as an additional area for requesting new map data. The method of claim 10, wherein the step of extracting the region comprises: firstly extracting an intersection region between the current display map region and the map region to be displayed due to the movement when the user accurately requests a map movement to east, west, south, or north. And selecting the remaining area of the displayed area except for the crossing area as an additional request area. 11. The method of claim 10, wherein in the step of extracting the region, when the user makes a request for reducing the display map, the current display map region is an intersection region, and the peripheral region is divided into four rectangular regions, and each is an additional region. Geographic information providing method of the client / server environment, characterized in that the selection.