FR2882451A1 - Cartographic data display system, has rules analyzer analyzing navigation commands relative to map series file to select map according to rules described in file, where selected map is provided to rendering engine to form cartographic zone - Google Patents

Abstract

The system has a rendering engine (6) forming a cartographic zone of a map from a cartographic database (5). A user interface (3) is provided to input navigation commands by a user with respect to the zone. A rules analyzer (7) analyzes the commands in relation with a map series file to select a map in the database according to the rules described in the map series file. The selected map is provided to the engine (6). An independent claim is also included for a computer program to be installed in a cartographic data display control device.

Description

SYSTEM FOR DISPLAYING MAP DATA AND

PROGRAM FOR ITS IMPLEMENTATION

  The present invention relates to geographic information systems.

  Digital geography aims to locate objects on the globe and create a map of the world or part of the world to stage these objects.

  Some computer applications that use digital maps offer navigation functions relative to the displayed area, that is to say functions of zooming, zooming, sliding of the map displayed on the screen, rotation of the map in the direction of the road followed, etc. In general, it is up to the user to first select the map to be displayed and then navigate through that map to display the desired area.

  For example, in a map-based route search application at different scales, the most relevant map should be chosen based on the position on the world map, the scale of maps available at that point, and the desired zoom level, which level is related to the size of the actual field area that the user wants to display. If you have a 1/200000 road map (1 cm on the map represents 2 km on the ground) and a 1: 50000 map and you want to display a 30 km route on a map 15-inch diagonal screen, the relevant equivalent scale is in the range of 1/100000. To display the route in full screen, the user has the choice between zooming the map to 1/200000 by a factor of 2 and zooming the map to 1/50000 by a factor of 2.

  In order to spare the user these considerations, there is an interest in automating the choice of the best map depending on the context. Now the most efficient and ergonomic way of carrying out this kind of automation depends very much on the type of mission entrusted to the user.

  Ergonomics is particularly important in the case where the geographic information system is used in an emergency by persons whose attention is directed elsewhere, in particular for armed forces, security or security interventions. rescue teams.

  The choice can become rather complex if the available types of maps vary not only by the scale but also by the mode of representation: - "raster" maps (simple matrices of georeferenced pixels); - georeferenced aerial or satellite photographs; - vector maps (carrying parameters or more generally semantics as to the objects represented); - digital terrain models, ...

  In current systems, the map display strategy is rudimentary or non-existent. The user selects the card himself from a loaded library. It sometimes has an indication on the cards available at a given position or in a given right-of-way, which simplifies the choice. The zoom controls do not usually affect the selection of a card, which results in pixelation sometimes very annoying for reading. When the system chooses itself a card, this choice is linked to a precise database and is not configurable.

  An object of the present invention is to respond flexibly to the need for automation of the map data display.

  The invention thus proposes a system for displaying cartographic data, comprising: a display screen for a cartographic area; a display engine for forming said map area from at least one map from a map data source; a human-machine interface for user input of navigation commands relative to the map area displayed on the screen; A map coverage file providing a structured description of map selection rules independent of the location of the map area displayed on the screen; and a module for analyzing the navigation commands in relation to the coverage file for selecting at least one map selected in the map data source according to the rules described in the coverage file, the selected map being supplied to the engine of the map file; display.

  The concept of cartographic coverage makes it possible to program basic interrogation rules for card data so that the user does not have to think about the interrogation mode adapted to each request. It can thus navigate more quickly and intuitively. The queries concern all the cards available on the various bases used. The result of the query can be displayed and used for any other processing.

  Map covers are not limited to one type of map. They can be used in any system integrating georeferenced digital maps, whether of satellite images, aerial images, raster maps, digital terrain models, digital elevation models, vector maps or any other georeferenced digital product.

  In a typical use of the system, the user goes on a mission with a terminal comprising the screen, the human-machine interface, the display engine and the rule analyzer. The map coverage file is installed in this terminal to correspond to the type of mission in question. At the same time as this coverage file, the system administrator can load into the terminal part of its map database, which part will be the map data source of the terminal. Another possibility is to record in the terminal one or more network addresses of sources from which the cards can be downloaded.

  Several user-selectable coverage files may also be provided depending on the mission or context.

  Another aspect of the invention relates to a written computer program for constituting a rule analysis module in a system as defined above. This program is to be installed in a map data display control device for controlling the display of a map area on a screen when it is executed by a processing unit of the device. It includes: instructions for receiving from a man-machine interface navigation commands relative to the displayed map area; instructions for analyzing the navigation commands in relation to a cover file providing a structured description of map selection rules independent of the location of the map area displayed on the screen; and - instructions for forming the map area to be displayed from at least one selected map in a map data source in accordance with the rules described in the coverage file.

  The map data display control device may be confused with the terminal where the data will be displayed. It can also be shared between this terminal and a remote device, for example located at a server accessible by a network.

  Other features and advantages of the present invention will become apparent in the following description of nonlimiting exemplary embodiments, with reference to the appended drawings, in which: FIG. 1 is a block diagram of a display system of FIG. cartographic data according to the invention; and FIGS. 2 and 3 are diagrams illustrating possible architectures of a system according to the invention.

  FIG. 1 schematically shows a system according to the invention which, in this example, is incorporated in a terminal 1 intended to be taken to the field by a user.

  2882451 -5- The terminal has a screen 2 where a map area can be displayed. This screen cooperates with a human-machine interface (HMI) software interface layer 3. The HMI 3 receives stimuli from input devices such as a keyboard 4a, a mouse 4b, etc. Naturally, other types of input devices (touch pad, tracking ball, joystick, cybergiove, etc.) are usable. The screen 2 itself can be tactile to send stimuli to the HMI 3 according to a position pointed by the user.

  In known manner, the HMI 3 allows the user to provide navigation commands relative to the displayed map area: "scrolling" in any direction of the plane, for example by dragging the mouse with its left button pressed to a point in the displayed area; magnification (zoom) or reduction (dezoom), for example by moving the mouse wheel in one direction or the other; possibly rotating, for example by clicking virtual buttons displayed next to the map area or by activating a dedicated tool and moving the mouse relative to a reference center.

  These navigation commands return to move the observation point of the scene that is the mapped data. A displacement in translation or in rotation in the plane of the map corresponds to the commands of scrolling or rotation, whereas a displacement by removal or approximation corresponds to the commands of zoom or zoom out. These navigation commands are relatively intuitive for the user by analogy to mechanical controls. HMI 3 can also provide map selection or scaling commands, which directly trigger source file selections rather than spatial navigation relative to the displayed area.

  The map data displayed comes from a digital map base 5 which, in the example of FIG. 1, is stored in a memory of the terminal 1. They are shaped by a display engine 6 in relation to the HMI 3 to produce the area displayed on the screen 2.

  The card submitted to the engine 6 so that it adjusts the area displayed on the screen according to the navigation commands received from the HMI 3 is selected in the base 5 by a rule analysis module 7. This works by applying selection rules that are provided by a map coverage file 8 saved in the terminal.

  In an advantageous embodiment, the map coverage file 8 is written in the XML language ("eXtended Markup Language"). This standard is well suited to semantic descriptions of rules such as those that can be applied by the analyzer 7. The program then includes a parser ("parser") of XML pages to retrieve the rules that will indicate how to query the database. to get the cards to display.

  These rules typically have priorities between the displayable card types. Based on the data available in base 5, the highest priority map will be displayed at the appropriate scale.

  The base 5 may also include grid templates whose coverage file 8 defines the display rules on the screen 2, either in superposition of the map area obtained from a map, or instead of this zone. if the database 5 does not contain a displayable map according to the rules of the coverage file. The presentation of the grid allows the user to locate in the displayed map area, and also allows him to navigate in areas not covered by the base 5.

  An example of an XML file usable as a cover file is presented below, in a particular case adapted to a vehicle tracking system, with maps whose type differs only in scale.

  <? xml version = "1.0" encoding = "ISO-8859-1"?> <sagis: coverages version = "1.0" xmins: sagis = "http: //www.sagem.com/ sagis /"> <sagis: coverage narre = "vehicle tracking" format = "USRP"> <sagis: raster name = "UlM" scale = "lM" minscale = "265k" maxscale = "1.33M" /> <sagis: raster name = "U200k" scale = "200k" minscale = "132k" maxscale = "266k" /> <sagis: raster name = "U100k" scale = "100k" minscale = "65k" maxscale = "133k" /> <sagis: raster name = "U50k "scale =" 50k "minscale =" 32k "maxscale =" 66k "/> <sagis: raster name =" U25k "scale =" 25k "minscale =" 3k "maxscale =" 33k "/> <sagis: raster name = "U3k" scale = "3k" maxscale = "4k" /> </ sagis: coverage> </ sagis: coverages> In this simple example, the coverage applies to cards that use the DIGEST USRP projection system. The name of this cover is "tracking_vehicles". It is then indicated that 1/1000000 scale cards are displayed when the equivalent scale on the user screen is between 1/265000 and 1/1330000. It is noted that the space of the possible scales is compartmentalized starting from the 1/3000 scale adapted to the plans of implantation of districts until 1/1330000 adapted to the visualization of a region.

  The use of cartographic coverage files 8 makes it possible not to solicit the user of an application in the choice of the best card adapted to his needs.

  A map administrator defines database usage profiles for different trades, mission types, or user profiles of the application. Once the system is set, the user can navigate the globe without worrying about the choice of cards.

  The system chooses the best map in the direction indicated in the map coverage selected by the user profile, according to the maps available in the base 5. Regardless of the amount of maps available and the particular location of the area displayed by the user, The analyzer 7 will apply the same rules defined by the cover file 8 to search the base 5 for the best usable card.

  The map covers make transparent to the end user the notion of map as a product or file. The addition of a map in the map databases to which the application is subscribed is immediately taken into account by the rule analyzer 7.

  The terminal 1 may contain several map coverage files 8, as illustrated in FIG. 1. A cover management interface 9 allows the user to select the coverage to be applied according to his mission or the phase of the mission in which it is.

  An informed user can optionally write an XML cover file via HMI 9, which must then have an XML editor. But in general, this role will be reserved for the system administrator. The cover management interface HMI 9 available to the cartographic administrator station preferably has an interface that allows it to compose the cover files in a formal language without having to write each character of the XML file. Each cover file thus composed can then be loaded into user terminals for use in the field.

  In the embodiment illustrated in FIG. 1, the terminal accesses locally the resources of the system, which have been provided to it by the cartographic administrator. Various other architectures and configurations of the system according to the invention are conceivable.

  In the case of FIG. 2, the terminal 1A comprises the screen 2, the navigation HMI 3, the display engine 6 and the rule analyzer 7. The cover file or files 8 are there recorded to be 7. But the map data source 5 is accessible to the rule analyzer 7 of the terminal 1A via a network interface 10 and a telecommunications network 11, such as for example the Internet or a network that owns the network. the system administrator. This source 5 may also consist of a decentralized card base in several servers as shown. It suffices to provide the rule analyzer 7, via the cover file 8, with the addresses (URLs) of the cards accessible remotely.

  The cover files 8 can also be downloaded via the network 11.

  The variant illustrated in FIG. 3 corresponds to the case of an application service rendered by a server 1C accessible by the network 11. The terminal 1B can then be limited to the screen 2, to the HMI 3, to the display engine 6 and to a network interface 12. These elements may correspond to those used by a web client. The server 1C hosts an application forming the rules analyzer 7, communicating with the terminal 1B via a network interface 13, as well as the map database 5 (which could also be external) and predefined coverage files 8, selectable by the user.

2882451 -10-

Claims (11)

  A map data display system, comprising: a screen (2) for displaying a map area; a display engine (6) for forming said map area from at least one map from a map data source (5); a human-machine interface (3) for user input of navigation commands relative to the map area displayed on the screen; - a map coverage file (8) providing a structured description of map selection rules independent of the location of the map area displayed on the screen; and a module (7) for analyzing the navigation commands in relation to the coverage file for selecting at least one map in the map data source according to the rules described in the coverage file, the selected map being provided to the map engine. display.   2. System according to claim 1, wherein the screen (2), the man-machine interface (3), the display engine (6), the analysis module (7) and the cover file ( 8) are installed in a terminal (1, 1A).   3. System according to claim 2, wherein the terminal (1) has a memory where is stored a database (5) constituting said source of map data.   4. System according to claim 2, wherein the map data source (5) is hosted in a server remote from said terminal (1A), to which the analysis module (7) accesses via a telecommunication network (11).   2882451 -11- 5. System according to claim 1, wherein the screen (2), the man-machine interface (3) and the display motor (6) are part of a terminal (1 B), while the module analyzer (7) and the cover file (8) are installed in a server (1C) to which said terminal accesses via a telecommunication network (11).   6. System according to any one of the preceding claims, wherein the cover file (8) is written in XML language.   A system as claimed in any one of the preceding claims, comprising another man-machine interface (9) for constructing the map coverage file (8).   8. System according to any one of the preceding claims, comprising several map coverage files (8) corresponding to different types of mission and selectable by the user.   9. Computer program to be installed in a map data display control device (1, 1A, 1C) for controlling the display of a map area on a screen (2) during a program execution by a unit method of processing the device, the program comprising: instructions for receiving from a man-machine interface (3) navigation commands relative to the displayed map area; instructions for analyzing the navigation commands in relation to a cover file (8) providing a structured description of map selection rules independent of the location of the map area displayed on the screen; and instructions for forming the map area to be displayed from at least one selected map in a map data source (5) according to the rules described in the coverage file.   2882451 -12- The program of claim 9, further comprising instructions for presenting another man-machine interface (9) for constructing the map coverage file (8).   The program of claim 9 or 10, further comprising instructions for selecting a map coverage file (8) from a plurality of registered coverage files.