The Design Of Object Oriented Map Model

The map is an important tool in people's life and production.With the progress of science and technology,the map has changed from traditional paper map to electronic map and three-dimensional map.Also,mapping methods were changed from handpainted to computer software rendering.The research on map has already gradually deepened,but the study of the map model is relatively lacking.The complexity and diversity of map make it difficult for map's making and sharing.Especially there are large differences between different professional maps.There is not a unified map model to define and specified the map,and it limits the map on the sharing and communication between different industries.Although,all kinds of mapping software or geographic information software have their own models,mostly from the point of data and focus on analyzing and processing the spatial data.Map is only one of the result by data analysis of those softwares.Although these softwares provide a variety of maps expression mechanism,to a certain extent,they pay much attention to map data expression and ignore other parts of a map and its entirety.There also has no unified model to define the maps.In the field of map research,the study of map model is always started from the point of data,focus on the formation of cartography theory that driven by database.Or,stay in its own profession,establish their own professional map models.These situations have brought some restrictions to map sharing and development in the map industry.In order to establish a map model with universality,sharing and extensibility to fill the research gaps for the establishment of a unified map model,this paper combines the basic theory of cartography and object-oriented,tries to start with map itself to make research on object oriented map model that highly compatible with map,and define the map from the view of model.First of all,define the basic composition of map and the process of data space transformation based on the theory of map and the theory of object oriented.At the same time,according to the composition of the map and the object oriented theory,the composition of the map and the map itself are abstracted as the object,and built the mathematical model to verify.Then,we make clear of the attributes,methods and the hierarchical relationships between the objects.Also,we build the model related database system to provide data support for the model.On these basis,a complete,detailed and object-oriented map conceptual model and logical model can be innovatively established.At the end,this paper has built the model driven mapping system to verify the correctness and effectiveness of the model.The advantages and disadvantages of the model were analyzed in the application process of the model system.It is hoped that the map model and the model based mapping system can provide a new idea and solution for the development of map research and map industry.