Research On Topological Relations And Spatial Geometric Operation Methods In Spatial Data Model

The spatial data model is an important way of expressing geographic information.It is used to describe the relationship between entities and entities in geospatial space.It is also an important theoretical basis for information processing and management technology platform.Spatial computing is the theoretical basis for spatial analysis and data processing in geographic information systems,providing basic spatial computing functions in geographic information application systems based on spatial data models will greatly enhance its applicability and scalability.Spatial operations can be divided into spatial relational operations and spatial analysis operations,the most basic in those operations are topological relational operations and spatial geometric operations.Therefore,based on the topological map model,this paper studies the most basic operations in spatial operations: topological relational operations and spatial geometric operations.The main research contents are as follows:1.Introduce the concept of graph theory to describe the relationship between geometric objects.Geometric objects in a topological map model are the basis of spatial operations.By abstracting the geometric object into the vertices in the graph,the relationship between the geometric objects is abstracted into the edge in the graph,and the adjacency matrix is used to represent the relationship between the vertex and the edge.Realized the relationship between geometric objects is represented by a matrix.2.Proposed a method for calculating topological relations by using geometry operations and node analysis.The geometric calculation will generate new nodes.By analyzing the structure of each node and the connected number,get a specific topological relationship,and based on this,the specific judgment methods of topological relations between points,lines and surfaces in DE-9IM are provided in the topology map model.3.Researched the conversion method of data from general data model to topological map model,and the spatial geometry operation is completed by using transformed vertex set,edge set,association relationship and geometric graph reconstruction.According to different data cases,the model conversion method of the corresponding data is analyzed.After the operation of the model transformation,different operation processes are designed for different spatialgeometric operations,and the corresponding operation results are obtained.Through experimental verification,the method of calculating topological relations by combining computational geometry and node analysis proposed in this paper is correct and effective.This method can not only accurately determine the types of various topological relations,but also can clarify the geometric characteristics in its topological relations,For example,when two objects are adjacent,they are adjacent by points or lines.The spatial geometry operation method is reasonable,the expected results can be obtained by the spatial geometry operation based on this method.