Design And Implementation Of Multi Resolution Terrain Database Based On Database Technology

Information age puts forward the new concept of Digital Earth and the GlobalInformation Grid brings great convenience to people’s life, however, the existing filesystem cannot meet the multi-resolution massive data access virtual terrain scene,especially in the aspect of management is limited by a lot. Scenario data cannot bepre-loaded into memory in integral form, but is divided into a number of small scenefile to store system, thus can greatly reduce the speed of the scheduling index,destruction of the space between the individual data query process. Most importantly,cannot ensure the safety stability of the data, and affect the multi-threaded file systemoperation and widely Shared network resources.Aiming at existing problems, this paper based on the modern spatial databasetechnology, spatial query, the study on distributed computing, data sharing and theobject modeling is an important structure of the space such as database, combined3dscene data characteristics, to obtain high fidelity real-time roaming state space, andrealize remote access and the dynamic load function, so it can effectively solve theproblem. Traditional file systems tend to be not visible operation, new databasetechnology can ensure the visual effect, under the condition of complete massive terraindata storage management, to implement the dynamic scheduling and real-time renderingof terrain data. Main content is:1. Analyse at home and abroad, multi-resolution terrain database technology,proposed the establishment of a global multi-resolution terrain database, provides a newplatform for the realization of simulation technology for global multi-resolution terrainenvironment, the database will change of topographic information make the dynamicresponse, dynamic update of real time data records in order to complete the database,real-time and better meet the needs of users, enhance the reliability of the simulation.2. Implementation of multiresolution terrain data storage of Sql Server databasetechnology, optimization of Pyramid model database structure, storage and managementmore flexible. Design of the database logic structure, rational utilization of databasestorage technology, realize the binary storage type storage of terrain data. Storage modedesign terrain data, uses the ADO interface to access and operation database, realize thedata storage and visualization for dispatch. 3. Quadtree index analysis technology, the design is based on quadtree data engine,the solution for each layer of each piece of pyramid model index, using the stratifiedhierarchical principle, in a short period of time reading massive spatial data, to extractdata from the target to meet user needs, ensure the timeliness and authenticity of terraindata at the same time.4. Analyse distributed database system, based on the client/server (C/S) mode ofmaster-slave database access method, to solve the remote scheduling terrain data,realize remote multi-user concurrent access to distributed spatial database, complete themassive data storage, management and indexing.5. Construction of multi resolution terrain database based on Sql Server. Accordingto the Pyramid model database structure to store data, using four forks tree indexingtechnique called terrain real-time terrain database in the network, real-time renderingthree-dimensional geographic information in the scene, so as to realize the roamingscene virtual geographic environment construction.