Research On Vector Data Organization Methods Based On Vector Tiles

Vector data which plays an important role in the geographic information system,is an important data model that abstract expression the spatial entities of real-world.With the GIS application extends to different areas,The amount of vector data is increasing faster and faster,and the interaction of system is increasing by users' requirements which brings new challenge for vector data organization methods.The simple visualization method of vector data based on raster tiles or geometric drawing method based on the whole can not meet the requirements for interoperability and the needs of system efficiency.To solve the problems all above,we need a better organization for vector data.On the basis of analysis and summary for the traditional vector data organization methods,the paper designs an organization method for vector data which is based on vector tiles.The first is vector data block culling and constructing multi-resolutions vector data model,the vector tiles as a carrier for transmission and expression of vector data,then restore the features of original data by combined vector tiles on the client side.To achieve the methods mentioned above,the main contents of the paper are as follows:1)Research the advantages and disadvantages of traditional vector data in the data organization,management and scheduling,understand the several ways of the multi-resolution vector data expression,so lay theoretical foundation for establish multi-resolution vector tile model.2)Study the related concepts of the geographic grid subdivision model,select the appropriate method of geographic grid subdivision as vector tile subdivision basis,design grid encoding rules as the unique number of vector tile,use the linear quadtree indexes for quick search of the vector tile.3)Design the concept model,logical model and physical model of vector tile,select the appropriate data format to recording properties and geometries of vector tile.Using the separately that store separately for properties and geometry information to avoid duplicate store property.Implement tile-based expression of vector data through the above steps.4)Analyze the existing vector features culling strategy,use block cutting for vector data on the service.And design the appropriate consolidation method of vector tile on the client to rebuild vector data.The premised of merge vector tile must ensure data integrity in visual and consistency.5)According to the above research and analysis,the paper design and implementation of a experiment system to verify the feasibility of the methods.Finally,combined the experiment system,use related data to test,the results show that the organization method based on vector tile of vector data could be maintained the characteristics in high precision and easy mapping while achieving well interaction,ensuring data fast scheduling and transmission.And the method of divide and rule for vector data enable the geography calculation method is easy spread from single-core to multi-core,from the stand-alone expansion to the cluster,for the development trend of big geographical data is more suitable.