CN104866549A - Terrain environment database system suitable for multi-agent simulation - Google Patents

Abstract

The invention relates to a terrain environment database system suitable for multi-agent simulation. Architectures, data models and specific data tables and file formats of databases are designed. The system consists of a large-scale terrain relational service database, a terrain service database manager, a data conversion tool, a terrain analysis application database, a terrain visualization application database, a network data communication module and a database application programming interface (API). The system integrates database information service, personnel data processing and operation, and application operation, and the system is divided into two data layers, i.e. a data service layer and a data application layer, so that a multi-agent simulation system can access high resolution terrain data efficiently in real time, and management and maintenance of large-scale terrain data and terrain visualization simulation are integrated, thus providing data support for real-time environmental analysis and tactical decision-making of intelligence troops.

Description

A kind of terrain environment Database Systems being suitable for Multi-Agent simulation

[technical field]

The present invention relates to a kind of terrain environment database, be specifically related to a kind of terrain environment Database Systems being suitable for Multi-Agent simulation, belong to Computer Warfare Simulation technical field.

[background technology]

Computer Warfare Simulation, as one modern military issue analysis design mothod method, plays an important role in the every field of war forecasting and decision assistant, operational concepts and tactics research, operational commanding and skill training and the military science research such as Armament Demonstration and experimental study.Along with going deep into the research of combat system complicacy, using multi-agent Technology to carry out modeling and simulation to combat forces and operation is that current operation emulates up-to-date research direction.Terrain environment database is important component part and the data basis of multiple agent combat simulation system, is the important evidence of the terrain environment analysis of intelligent troops and tactical decision.

Abroad to multiple agent operation simulation Technique Study comparatively early, have developed corresponding Simulation Experimental Platform, as the Swarm Multi-Agent simulation platform of Einstein and the Sang Tafei research institute (SFI) of analytic centre of USN (CNA).But, on the one hand, higher to the description level of abstraction of landform environmental data in these analogue systems, data scale is less, and resolution is lower, cannot meet for real battlefield surroundings, carry out the needs of high resolving power emulation experiment, on the other hand, the terrain simulation database of these experiment porchs is applied databases, only meet certain Simulation Application input, process, store and the needs of usage data, and lack the service type database large-scale data being carried out to maintenance management.

Therefore, for solving the problems of the technologies described above, the necessary terrain environment Database Systems being suitable for Multi-Agent simulation providing a kind of innovation, to overcome described defect of the prior art.

[summary of the invention]

For solving the problem, the object of the present invention is to provide a kind of terrain environment Database Systems being suitable for Multi-Agent simulation.

For achieving the above object, the technical scheme that the present invention takes is: a kind of terrain environment Database Systems being suitable for Multi-Agent simulation, and it comprises large-scale terrain relationship type service database, Terrain Service database manager, data conversion tools, terrain analysis application data base, terrain visualization application data base, network data communication module and database application DLL (dynamic link library); Wherein, described Terrain Service database manager is connected with terrain analysis application data base with large-scale terrain relationship type service database, data conversion tools, terrain visualization application data base by network data communication module; Described large-scale terrain relationship type service database runs on Terrain Service database server, is connected with Terrain Service database manager by network data communication module; Described data conversion tools is connected with Terrain Service database manager by network data communication module; Described terrain analysis application data base is connected with Terrain Service database manager, by database application DLL (dynamic link library) for Simulation Application provides data, services by network data communication module; Described terrain visualization application data base is connected with Terrain Service database manager by network data communication module.

The terrain environment Database Systems being suitable for Multi-Agent simulation of the present invention are further: described large-scale terrain relationship type service database comprises topographical surface spot elevation entity, locus point entity, point-like character thing entity, line feature thing entity, planar characteristic body entity, texture image entity and model object entity; Described point-like character thing entity, line feature thing entity and planar characteristic body entity, realize location by some or several locus points.

The terrain environment Database Systems being suitable for Multi-Agent simulation of the present invention are further: described terrain analysis application data base builds according to 5 layer data library model of basic grid layer, grid index layer, feature locations layer, characteristic attribute layer and the motor-driven layer of road.

The terrain environment Database Systems being suitable for Multi-Agent simulation of the present invention also can be: described network data communication module adopts ethernet communication mode, use the server client form of ICP/IP protocol, the communication server embeds in Terrain Service database manager, and client embeds in large-scale terrain relationship type service database, data conversion tools, terrain analysis application data base and terrain visualization application data base and uses.

Compared with prior art, the present invention has following beneficial effect: the terrain environment Database Systems being suitable for Multi-Agent simulation of the present invention are for the actual demand of Multi-Agent simulation for battlefield environment database, by the information service of database, the data processing of personnel runs unification mutually with operation and application, realize the Database Systems pattern of " trinity ", solve Multi-Agent simulation system high resolving power terrain data real-time high-efficiency is accessed, for large-scale terrain data management maintenance and the emulation integrated practical problems of terrain visualization, for the real time environment analysis of intelligent troops and tactical decision provide data supporting.

[accompanying drawing explanation]

Fig. 1 is the system assumption diagram being suitable for the terrain environment Database Systems of Multi-Agent simulation of the present invention.

Fig. 2 is large-scale terrain relationship type service database ER illustraton of model of the present invention

Fig. 3 is large-scale terrain relationship type service database data list structure figure of the present invention

Fig. 4 is terrain analysis application data base hierarchy Model figure of the present invention

Fig. 5 is road topology figure of the present invention

Fig. 6 is the motor-driven model of a layered structure figure of road of the present invention

Fig. 7 is terrain texture map performance index modular concept figure of the present invention

[embodiment]

Refer to shown in Figure of description 1 to accompanying drawing 7, the present invention is a kind of terrain environment Database Systems being suitable for Multi-Agent simulation, it is by the information service of database, the data processing of personnel runs unification mutually with operation and application, be divided into data service layer and data application layer two data hierarchies, solve Multi-Agent simulation system for the access of high resolving power terrain data real-time high-efficiency, for large-scale terrain data management maintenance and the emulation integrated practical problems of terrain visualization, for the real time environment analysis of intelligent troops and tactical decision provide data supporting.

The terrain environment Database Systems being suitable for Multi-Agent simulation of the present invention comprise large-scale terrain relationship type service database, Terrain Service database manager, data conversion tools, terrain analysis application data base, terrain visualization application data base, network data communication module and database application DLL (dynamic link library) (API), wherein:

Terrain Service database manager runs on Terrain Service database management computer, by network data communication module and large-scale terrain relationship type service database, data conversion tools, terrain visualization application data base is connected with terrain analysis application data base, it is the middleware of Connection Service database and application data base, in data acquisition phase, manager is by the various terrain datas after data conversion, be stored in large-scale terrain relationship type service database by computer network, and by domain expert for various topographic entity in the affecting parameters input database record of operation, in the market demand stage, user operation manager is according to the actual needs of Simulation Application, the setting theater of war, resolution, the topographical constraint such as data content, read from large-scale terrain relationship type service database and generate terrain data file, be sent in terrain visualization application data base and terrain analysis application data base by network, for Simulation Application provides data, services,

Large-scale terrain relationship type service database runs on topographic database server, be connected with Terrain Service database manager by network data communication module, it is the physical memory cell of graphic data on a large scale, general relational data library operating systems is adopted to realize, multiple relation database tables that are mutually related are used to store data, in data acquisition phase, store according to the various terrain datas that manager provides, in the application stage, according to the visiting demand of manager, data are provided;

Data conversion tools runs on data coordinate conversion computer, be connected with Terrain Service database manager by network data communication module, for Terrain Service database manager provides service, use in the typing stage of data, by using this instrument, by multiple means and approach, in the global range obtained, the data not meeting the requirement of internal system data model in the terrain data (comprising terrain elevation data, soil soil property data, cultural traits data and terrain texture data etc.) of various general international standard carry out Data Format Transform;

Terrain analysis application data base applies on each emulation terminal computing machine, be connected with Terrain Service database manager by network data communication module, by database application DLL (dynamic link library) (API) for Simulation Application provides data, services, the form of file based database application is adopted to realize, according to basic grid layer, grid index layer, feature locations layer, 5 layer data library model of characteristic attribute layer and the motor-driven layer of road build, in the process of simulation run, intelligent simulation entity, read by elevation, intervisibility judges, the API such as distance measurements calculation read terrain data information, for tactical decision provides basis of environmental,

Terrain visualization application data base applies on each emulation terminal computing machine, be connected with Terrain Service database manager by network data communication module, being read and play up terrain information in terrain visualization application data base by graphics rendering engine for Simulation Application provides data, services, the form of file based database application is adopted to realize, mainly include triangle wire side to divide and terrain texture map two parts, in the process of simulation run, emulation render engine reads triangular facet and the data texturing of terrain visualization application data base by database application DLL (dynamic link library), carry out three-dimensional visualization to landform to play up, for multiple agent operation simulation process information provides visual display means,

Described database application DLL (dynamic link library) (API) applies on each emulation terminal computing machine, be mainly used in the reading of terrain analysis application data base and the analysis of terrain data, the physical form of dynamic base is adopted to exist, can embed in analogue system and use, have cross-platform universal performance, in the process of simulation run, Simulation Application realizes reading terrain data information by this API, tactical analysis is carried out to landform, the based data service functions such as planning road maneuvring route.

Described network data communication module runs on each computing machine of Database Systems, the network service of fulfillment database system difference in functionality intermodule, adopt ethernet communication mode, use the server client form of ICP/IP protocol, the communication server embeds in Terrain Service database manager, and client embeds in large-scale terrain relationship type service database, data conversion tools, terrain analysis application data base and terrain visualization application data base and uses.

Fig. 1 is terrain environment database architecture figure;

Terrain environment Database Systems are made up of large-scale terrain relationship type service database, Terrain Service database manager, data conversion tools, terrain analysis application data base, terrain visualization application data base, network data communication module and database application DLL (dynamic link library) (API).Wherein, large-scale terrain relationship type service database, Terrain Service database manager and data conversion tools run on remote service end, terrain analysis application data base, terrain visualization application data base and database application DLL (dynamic link library) (API) run on Simulation Application this locality, are connected between each functional module by network data communication module.

The general operational process of system is:

1), after various terrain environment data being changed by data conversion tools by Terrain Service database manager, large-scale terrain relationship type service database is stored into;

2) according to specific artificial tasks needs, the terrain environment data in large-scale terrain relationship type service database are read by Terrain Service database manager, generate terrain analysis application data base and the terrain data library file needed for terrain visualization application data base, and be sent to Simulation Application local computer by network data communication module.

3) local Simulation Application reads the data file in terrain analysis application data base and terrain visualization application data base by database application DLL (dynamic link library) (API), carry out the dynamic dispatching between disk and internal memory, realize real time environment analysis and the tactical decision of intelligent troops, and the three-dimensional visualization display of battlefield terrain environment.

The data model of service database and application data base and data layout:

1) design data of large-scale terrain relationship type service database

The design of large-scale terrain relationship type service database, include conceptual design and two stages of logical design, wherein use ER conceptual model in conceptual design, set up ER figure, ER again by summing up schemes the transformation rule of tables of data, in conjunction with the actual features of large-scale terrain relationship type service database, the ER conceptual model of terrain data is converted into the patrolling of tables of data that DBMS uses and seizes structure, process is carried out in strict accordance with the ER method of specification and conversion method, thus ensure that the rationality of design, eliminate data redundancy and ensure that the efficient of database and consistance.

(1) large-scale terrain relationship type service database ER model

Entity expressed by large-scale terrain relationship type service database comprises topographical surface spot elevation entity, locus point entity, point-like character thing entity, line feature thing entity, planar characteristic body entity, texture image entity and model object entity.Due to the point-like character thing entity in topographic database conceptual model, line feature thing entity and planar characteristic body entity, location is realized by some or several locus points, therefore between point, line, surface three kinds of entities and locus point entity, just define the spatial relationships of 1: 1 and 1: N, pass again owing to being formed between surface elevation point entity and other entities ties up in this database does not have actual meaning, therefore surface elevation point is as independently entity existence, the large-scale terrain relationship type service database ER model formed, as shown in Figure 2.

(2) large-scale terrain relationship type service database Data Sheet Design

By each key element in the ER figure of drafting, be converted to tables of data and field thereof.Respectively tables of data is set up for all entities in ER figure.Surface elevation point entity is except ground Table Properties, the field of other attributes outside earth model and projection type respectively in corresponding data table, by (longitude, latitude) as a combination major key, according in terrain data abstract model for the model of attributive character hierarchical description, by abstract for earth's surface attributive character be motor-drivenly affect rank, firepower affects rank and (finds to affect rank, injure and affect rank) affect rank with communicating, therefore for the ground Table Properties of surface elevation point entity, setting up respectively motor-drivenly affects rank table, find to affect rank table, injuring affects rank table and affects rank table with communicating, in surface elevation point entity list corresponding set up motor-driven, find, injure, communication affects level field, and as each external key affecting rank table, ground ball type and projection type are set up tables of data respectively, in surface elevation point physical data table, set up earth type number and projection type number field respectively, and it can be used as the external key of ground ball type and projection type.In point-like entity, Linear Entity and planar entity, except affecting attribute, classification and kind, other set up respective field, to number as its major key, identical with the ground Table Properties of surface elevation point entity for the process affecting attribute, corresponding level field is set up and as external key in physical data table, quote properties level table, respectively tables of data is set up for classification and kind, and set up corresponding field in point, line, surface physical data table.For use relation, in the tables of data using entity, directly set up texture use and model use field as the external key of corresponding data table major key.For positioning relation, in space orientation point data table, set up some entity number, face entity number, line entity number field respectively, and as external key, corresponding physical data table is quoted.Final data list structure is converted to as shown in Figure 3 by above.

2) design data of terrain analysis application data base

Terrain analysis application data base is the topographic database needing real time access in Combat Simulation System operational process, also be the data basis of the real time environment analysis of intelligent troops and tactical decision, it is the emphasis that this patent is different from other general terrain simulation database, when designing, the data service capabilities of the quick real time access of main outstanding intelligent troops, therefore has many different in data memory format, Information Organization structure and physical space distribution etc. compared with large-scale terrain relationship type service database.According to the analysis of landform simulation data base functional requirement, terrain analysis application data base will adopt the file based database application be made up of multiple file, and distribution runs on each Simulation Application.

(1) hierarchical model of terrain analysis application data base

Which type of structural model terrain analysis application data base adopts, and decides primarily of the storage content of database and the describing method of content.According to the analysis for terrain information abstract model, the data stored in application data base can be summarized as terrain elevation data, cultural traits position data and characteristic attribute data three class.The method of terrain data is described, mainly contain Grid Method and vector method two kinds, landform is divided into multiple grid by Grid Method exactly, each grid is described, thus reach the object of each place of landform being carried out to data description, adopt the method to be described landform, there is the advantage of convenient location, inquiry and various analytical calculation, but be subject to describing precision and data volume this on the impact of contradiction, apply and there is certain limitation; Vector method can describe comparatively accurately to data, the problem of data redundancy can be avoided simultaneously, but it is comparatively complicated in search location and various model calculate, simple use vector method, can not contentedly graphic data describe needs, therefore landform application data base have employed and Grid Method and vector method combined, for the Hierarchical structure model of different description object hierarchical descriptions.Terrain analysis application data base hierarchy Model, as shown in Figure 4.

A. basic grid layer

The stress and strain model of basic grid layer is corresponding with the stress and strain model of landform altitude model (DEM), each coarse gridding ground elevation information and property index information, therefore again basic grid layer is divided into landform altitude layer and property index layer, adopt the storage organization of this kind of basic grid layer can for the altitude figures of whole landform and each department for motor-driven, find, injure and carry out complete description with the impact of communication efficiency, data corresponding to each grid are: (elevation, motor-driven rank, find rank, injure rank, communication rank).

B. feature locations layer

Because feature locations data are compared with altitude figures, not be distributed in whole landform, but relatively little be concentratedly present in some regions, if therefore adopt the method for rasterizing to be described, while causing a large amount of data redundancies, also have impact on the positioning precision of feature, the method for vector quantization therefore should be adopted to express.Feature locations layer is again according to the abstract shapes of landform cultural traits entity, and divide in order to point, line, surface characteristic layer, the storage data of each feature are: (characteristic ID, category IDs, kind ID, title, motor-driven rank, find rank, injure rank, communication rank, position starting point, position end point), there is no spatial relation between each data, but order carry out linear storage.

C. the motor-driven layer of road

Road is a kind of special line feature target, except meeting the searching requirement of general line feature target, also needs the path planning for intelligent troops to provide the road net data information on basis.Such as, need to realize appointment road terminal, intelligent troops are made automatically to select road to carry out motor-driven function, so, the linear memory relation of simple other line feature of use, brings huge complex calculation will to the path planning model of intelligent troops, the requirement of real-time can not be met, therefore just to need be the road information that the path planning model of intelligent troops provides through special node store structure design, for this reason, and the special independent design motor-driven layer of road in terrain simulation application data base.

Road information mainly contains two kinds of storage meanss as a kind of Vector Message, and one is simple relation storage means, and one is storage manner of topology relations.Simple relation storage means, namely store with forerunner and follow-up linear relationship between each entity, this storage means relation is simple, be convenient to carry out searching and traversing operation for some entities, but the spatial relationship between each entity cannot be expressed, complicated relationship analysis computing cannot be completed based on these data; Storage manner of topology relations, namely store with certain space or hierarchical relationship between each entity, this storage means realizes complicated, but the irrealizable complex relationship computing of simple storage relation can be completed, but compared with simple relation storage means, for determining that individual traversing operation is not very convenient again.

In emulating owing to fighting, intelligent troops have the actual needs of complex space relational calculus for road information, therefore, must comprise the road information stored with topological relation at the motor-driven layer of road.Between the road in real world, there is not the hierarchical relationship that certain is clear and definite, but be interweaved, manifest a kind of netted spatial relationship, therefore for the actual features of road information, adopt the topological structure of figure to describe to it the most suitable.If V is a nonempty set, E is V element right (multiple) set, claims ordered pair (V, E) for figure, is designated as G=(V, E).Wherein the element of V is called the summit of G, and V is called the vertex set of G, if E is the ordered pair set of element in V, then the element of E is called the arc of G, and E is called the arc collection of G, and G is called digraph; If E is the unordered pair set of element in V, then the element of E is called the limit of G, and E is called the limit collection of G, and G is called non-directed graph.Because road does not have directive, therefore the figure of road composition is non-directed graph, according to the definition for figure in graph theory, road topology structure is made abstractdesription as shown in Figure 5.Wherein, comprise five highways, according to the abstract model of wire information, Ge Tiao highway is expressed as the broken line that multiple location point is connected, the road information provided with terrain simulation service database unlike, in the motor-driven layer of road, by each bar road intersect location point, insert in original road data, to adapt to the data needs that mileage chart shape topological structure is expressed.

According to general Graph Theory, can using all location points in road as summit, using all broken lines as limit, thus build a mileage chart, all roading functions can be realized, but in the mileage chart built according to such method, contain a large amount of linear informations, instead of pure pattern structure, as the 2nd in road 1,3,4,5 summits, be exactly a kind of linear relationship, therefore this figure, do not make full use of line style and pattern structure advantage separately, to such an extent as to have impact on the search efficiency of road information and the utilization factor of storage space.Therefore, this patent takes full advantage of the own characteristic of road information, and the application target of terrain simulation, devise the storage organization of mileage chart, this road model takes full advantage of the respective advantage of line style and pattern structure, two kinds of structures is merged, and the basic thought setting up this structural model is:

By all location points of road net, be divided into two classes, one class is as the summit of road topology figure, comprise the end points of all roads and the point of crossing of road and road, shown in the thoroughfare position point of filling as used grid in Fig. 6, another kind of is common thoroughfare position point, comprises except the location point as summit in all thoroughfare position point, shown in the thoroughfare position point of filling as do not used grid in Fig. 6.No matter whether there is general position point between summit and summit, no matter also there is several general position point, all be regarded as a limit in mileage chart, like this according to the definition for figure in graph theory, road topology relation is set up, wherein the end points of V={ road and the point of crossing of road and road }, the end points of E={ road and the annexation between road and the point of crossing of road to, G (road topology figure)={ V, E}.But by common thoroughfare position point, be excluded in the loss that can cause segment path shape information outside vertex set V, therefore the road segment segment corresponding to all limits in mileage chart is carried out simple linear memory separately, change and traditional a road is carried out as an entity method that stores, and by the location index number of road segment segment, power as road topology figure limit is described, so far, just the positional information of all roads to be expressed for motor-driven for road layer is carried out scientific and reasonable structure organization, but because its attribute of road is substantially identical, according to current structural model, the carrying out to the different road segment segment of same path repeat is needed to define, the retrieval of a certain bar road of specifying also is brought to the impact of efficiency aspect simultaneously, therefore in structural model, add again the essential information structure be integrally described by road especially, mainly comprise the description to its attributive character, complete road net structure model as shown in Figure 6.

D. grid index layer

Description for spatial data mainly contains two kinds of methods, one is that rasterizing describes, another kind is that vector quantization describes, the method of rasterizing is adopted to be easy to position spatial data search and manage, but data volume is large, adopt the method for vector quantization to save storage space, describe accurately, and the spatial operation of some complexity can be carried out.Because feature locations (comprising road) data use the method for vector quantization to be described, therefore realize high efficiency space querying comparatively difficult.Such as, armored vehicle needs to obtain all pools and river information in the process of ground maneuver, then carry out collision detection, thus affect the motor-driven of armored vehicle, for this functional requirement, if use the information of the most original feature locations layer, just need among each simulation step length of armored vehicle movement, to all lines, face data carry out cephalocaudal traversal, first pool and river characteristic is found, then judge that whether armored vehicle there occurs with river with this pool to contact, thus the motor-driven of armored vehicle is had an impact, simple this type of locus locating function of information realization using the most original feature locations layer as can be seen here, implementation efficiency is lower, if data volume is larger, then cannot meet the performance requirement of application data base real-time.Road motor-driven layer situation is identical therewith, although employ complicated topological structure, if need to realize searching the function apart from certain a bit nearest road, efficiency is still lower.

For making full use of vector data accurate positioning, storing the advantage that data space utilization factor is high, overcoming the defect of some the space querying functional realiey difficulty brought thus simultaneously, therefore in the hierarchical structure of terrain simulation application data base, add grid index layer.Grid index layer is in fact also use Grid Method to store spatial data.Similar to basic grid layer, landform is also carried out the division of grid by grid index layer, but its size of mesh opening wants large compared with basic grid layer, the size of concrete size of mesh opening, need according to feature quantity number and density degree determine.The index of characteristic (comprising road) is stored in each grid of grid index layer, owing to judging that operation entity is higher at some grid efficiencies, therefore just by first judging that place grid comprises those characteristics, then judge that mutual method occurs concrete and which feature object, improves the space querying efficiency of characteristic again.Because armored vehicle is in motor-driven process, be subject to line, region feature entity impact larger, need frequent carrying out with it alternately, therefore point-like information is only comprised from the grid index layer of topographic database in the past different, in grid index layer in the patent, point, line (comprising road) and planar feature are all stored its index value in index level.

E. characteristic attribute layer

Content described by characteristic attribute layer is the attribute information of various topographic entity in application data base, in fact be exactly the motor-driven rank in service database, find rank, injure rank and express with the local file of the rank tables of data that communicates, for other Information Levels of application data base, the concrete data of characteristic attribute are provided, thus solve the data redundancy problem of application data base to greatest extent, make full use of storage space, improve the efficiency that information uses.

(2) file layout of terrain analysis application data base

According to the hierarchical model of application data base, can by the file included by application data base, be divided into basic grid data file accordingly, grid index data file, feature locations data file, characteristic attribute data file and the motor-driven data file of road, All Files all adopts binary mode to store, read to facilitate application program and save storage space, All Files form is when designing, all embody a kind of design philosophy, the direct reading of file data can be ensured exactly and support dynamic data scheduling, to make full use of memory headroom, guarantee program Effec-tive Function.

A. basic grid data file

The file layout of basic grid data file is:

File header { grid interval (double), grid columns (int), grid line number (int) }

Data division: { (elevation (double), motor-driven grade (int), find grade (int), injure grade (int), communication, levels (int)) ..., wherein data division is the grid according to the most lower left corner from whole terrain mesh, carry out storing according to the order of line order, wherein elevation represents the high level of grid, and remainder data represents the characteristic attribute of this grid.

B. grid index data file

Grid index data file is divided into three parts, and Part I is file header, and Part II is the grid index of feature, Part III is characteristic ID data, according to this stored in file format, can ensure that the size of the Data Entry of the grid index part of feature is identical, ensure that the efficiency of reading.

Wherein, file header is identical with basic grid data file, after file header from the lower left corner of index grid, store according to line order, each Data Entry is { position (int), number (int) }, after above data, it is the Part III of file, according to the storage order identical with index grid, the ID of all feature entities is carried out sequential storage, like this, after have read position in some index grids of file Part II and number, the ID of all feature entities that it comprises can just directly be read.

C. feature locations data file

Feature locations data file comprises three parts, and first part comprises the number (int) of feature, and the second part is the essential information of all feature entities, and the 3rd part is the location point data of all feature entities.

The second part of file, sequential storage { (characteristic ID (int), category IDs (int), kind ID (int), title (char (256), motor-driven rank (int), find rank (int), injure rank (int), communication rank (int), position starting point (int), position end point (int)) }, the 3rd part order stores the location point of all feature entities, and each location point data is { X (double), Y (double), Z (double) }.

D. characteristic attribute data file

Characteristic attribute data file is divided into five parts, motor-driven, find, injure, communication rank data and arm of the services categorical data, wherein the file storage structure of front four parts is roughly the same, be divided into again data head and data two parts, data head is { rank number (int), arm of the services number n (int), first arm of the services code name (int), second arm of the services code name (int) ... n-th arm of the services code name (int) }, data division is according to { rank (int), to the influence coefficient (doubie) of first arm of the services ... to the n-th arm of the services influence coefficient (double) } sequential storage, Part V is according to { arm of the services code name (int), title (char (256) } form, store all arm of the services data needing to describe.

E. the motor-driven data file of road

According to the structural model of the motor-driven layer of road, the motor-driven data file of road is divided into four parts, Part I is file header, comprise { road quantity (int), the quantity (int) on limit } two data, Part II is road data, and Part III is the data on the limit in topological relation, Part IV be data a little.

The road data of Part II is according to { sequence number (int), limit starting point (int), limit terminal (int), motor-driven rank (int), find rank (int), injure rank (int), communication rank (int) structure carry out order storage.The data on the limit of Part III, according to the structure of { sequence number (int), starting point (int), terminal (int) }, store according to the order of the road belonging to it.Part IV by all point data according to { sequence number (int), X (double), Y (double), vertex number (int) } structure, store according to the data sequence on Part III limit, wherein vertex number refers to the summit unique number in a database in road topology structure, other common location points, and summit numbering is set to 0.The limit starting point of road data and limit terminal correspond to the sequence number in the data of limit, and the starting point in the data of limit and terminal correspond to the sequence number of point data, thus define the topological structure of the motor-driven layer of complete road.

3) design data of terrain visualization application data base

Terrain visualization application data base is the database of the geometric properties being used for specially describing terrain visualization model and the visual attribute had thereof.The geometric properties that terrain visualization simulation data base records essentially describes the polygon and vertex position thereof that form topographical surface, and visual attribute then describes the information such as the color corresponding with the polygon of geometric properties, material, texture.Terrain visualization simulation data base directly can be used by real-time system, and according to the information real-time rendering terrain scene of database, therefore for ensureing the efficiency played up, the general form of file that adopts stores.

(1) proposition of texture performance index

This patent is the performance ensureing visual application data base texture, the Design and implementation performance index of texture, the generation of terrain visualization application data base texture file, according to the actual needs of Simulation Application, according to performance index requirement, generated by large-scale terrain relationship type service database.

According to the ultimate principle of texture, there are three kinds of corresponding relations: one is a pixel of the texel just corresponding screen of a texture image between the texel of texture image and the pixel of screen, this is a kind of optimal state, the full-scale mapping of texture image, and display effect is best; Two is corresponding multiple screen pixels of texel of a texture image, in this case, will carry out amplifications filtration, thus cause the decline of picture quality, and affect the display effect of texture to texture image; Three is corresponding screen pixels of multiple texels of texture image, in this case, compression will be carried out to texture to filter, thus also can have an impact to the quality of texture image, but due in this case, softening can be carried out to image by senior texture mapping technology such as Mipmap, again because figure itself is less, therefore in this case little compared with the second situation on the impact of visual effect generation.Therefore, for improving the result of use of terrain texture, how suitable the size of selection texture and texture is applied to the topographical surface of suitable size, to reach or close to the first desirable corresponding situation of texture, just to become the key of terrain texture application.Terrain texture is excessive, and the texture memory of computer hardware cannot bear; Too small, then produce serious image fault, affect the visual effect of terrain visualization.Research for terrain texture performance index is less, some empirical values are only provided in physical data, again because the terrain simulation of armored force Combat Simulation System is the emulation of a kind of ground surface or terrain, comparatively high-altitude terrain simulation, requirement for texture is higher, and the performance index therefore for terrain texture carry out determining quantifier elimination, have stronger actuality and practicality, effectively can reduce the number of times of modeling test, greatly improve the efficiency of terrain simulation modeling.

Due in texture, texel is corresponding with pixel is a kind of ideal texture situation, simultaneously, again due under specific observation condition, between the actual range of landform and screen coordinate, also there is certain proportionate relationship, therefore herein, using the length of actual landform corresponding for every texel as the index weighing texture performance, unit is rice/texel (m/textel).Below for the performance index of texture set up its mathematical model.

Model hypothesis: observer vertically watches landform (this situation requires the highest to terrain texture) at certain altitude.

Model variable:

Mpt: every landform rice number corresponding to texel

H: be the height on view distance ground

Hfov: the level angle of visual field

Vfov: the vertical angle of visual field

X: the horizontal pixel of screen

Y: the vertical pixel of screen

Modular concept as shown in Figure 7.

The level angle of general visual field is identical with the ratio of the ratio of vertical angle and screen level pixel and vertical pixel, therefore obtains following formula:

$\mathrm{mpt}=\frac{2\×\frac{h}{\tan (\mathrm{hfov}/2)}}{x}$

$\mathrm{mpt}=\frac{2\×\frac{h}{\tan (\mathrm{vfov}/2)}}{y}$

For the visual simulating of armored force Combat Simulation System, general viewpoint is at distance ground 2-3 rice, vision range is generally about 30 degree, therefore h=2 is established, hfov=30, x=1024,0.015 is approximately equal to according to computing formula mpt, namely according to above assumed condition, in the texture of terrain visualization emulation, about 0.015 meter of the corresponding actual landform of each texel of texture image.

(2) OpenFlight terrain visualization application data base and Hierarchical Optimization method thereof

The terrain visualization application data base of this patent adopts the OpenFlight document format data of increasing income to store, and is optimized on this basis, raises the efficiency.

OpenFlight visual simulating database, be MPI (Multigen-Paradigm) company specially for the actual demand of visual simulating application, and the hierarchical data storehouse of design and development.This database has not only been full of storage and the access function rapidly and efficiently of model visualization information, also support the expansion of many senior model cootrol technology in visual simulating simultaneously, become visual simulating field to be most widely used, function is visual simulating database the most comprehensively, therefore also becomes the industrywide standard of the visual simulating database field fact.

OpenFlight visual simulating database adopts a kind of data structure organization form of tree-like, node type, level, this is the key being different from other three-dimensional data base Organization of Data forms, this data base organization form, not only be convenient to the adjustment and the editor that when modeling, database are directly carried out to structure, also be convenient to carry out various traversal when real-time rendering to model, how determine that the hierarchical structure of tree structure has important impact for rendering efficiency.

This patent adopts the hierarchical structure of space structure to database to be optimized.In the database layer level structure be optimized according to space structure, scene domain is divided into four regions, for a group node is set up in each region, under atural object in this region is placed on this group node, the scope of such region group node is less, in the viewing volume test for intersection of rejecting operation, only the 1st region is crossing with it with the 3rd region, therefore only the data under the 1st and the 3rd group node are sent to render pipeline to play up, thus reduce the burden of render process, improve the efficiency of drawing.

Above embodiment is only the preferred embodiment of this creation, and not in order to limit this creation, any amendment made within all spirit in this creation and principle, equivalent replacement, improvement etc., within the protection domain that all should be included in this creation.

Claims (4)

1. be suitable for terrain environment Database Systems for Multi-Agent simulation, it is characterized in that: comprise large-scale terrain relationship type service database, Terrain Service database manager, data conversion tools, terrain analysis application data base, terrain visualization application data base, network data communication module and database application DLL (dynamic link library); Wherein, described Terrain Service database manager is connected with terrain analysis application data base with large-scale terrain relationship type service database, data conversion tools, terrain visualization application data base by network data communication module; Described large-scale terrain relationship type service database runs on Terrain Service database server, is connected with Terrain Service database manager by network data communication module; Described data conversion tools is connected with Terrain Service database manager by network data communication module; Described terrain analysis application data base is connected with Terrain Service database manager, by database application DLL (dynamic link library) for Simulation Application provides data, services by network data communication module; Described terrain visualization application data base is connected with Terrain Service database manager by network data communication module.

2. be suitable for the terrain environment Database Systems of Multi-Agent simulation as claimed in claim 1, it is characterized in that: described large-scale terrain relationship type service database comprises topographical surface spot elevation entity, locus point entity, point-like character thing entity, line feature thing entity, planar characteristic body entity, texture image entity and model object entity; Described point-like character thing entity, line feature thing entity and planar characteristic body entity, realize location by some or several locus points.

3. be suitable for the terrain environment Database Systems of Multi-Agent simulation as claimed in claim 1, it is characterized in that: described terrain analysis application data base builds according to 5 layer data library model of basic grid layer, grid index layer, feature locations layer, characteristic attribute layer and the motor-driven layer of road.

4. be suitable for the terrain environment Database Systems of Multi-Agent simulation as claimed in claim 1, it is characterized in that: described network data communication module adopts ethernet communication mode, use the server client form of ICP/IP protocol, the communication server embeds in Terrain Service database manager, and client embeds in large-scale terrain relationship type service database, data conversion tools, terrain analysis application data base and terrain visualization application data base and uses.