Design And Management Of Cartographic Symbol Database

Spatial data in GIS are expressed in the form of point, line and region geometry, which requires that GIS systems must have the wealth of point, line and plane symbols to support. It needs to establish a complete cartographic symbols and it needs cartographic symbols libraries to manage. So, it is very important for the application of GIS to design complete, systematic, accurate cartographic symbol libraries.Every kind of GIS software has its own symbol edit module. Nowadays, some excellent GIS software home and abroad provides a common drawing symbols libraries. It can make the symbol symbolic according to certain rules. Also it provides a user-defined symbol functions. The users can design complicated symbol by the tool of symbol editing to satisfy their requirement. Those softwares are just like the CorelDraw, ArcGIS, MapGIS, MapInfo, and SuperMapand so on. The question is that those soft wares have a big difference on thequantity, quality and sorts of symbol and lack communication. They have a big problem on symbol for versatility. They are hard to fit for each other GISsoftware. They all take the form of a file library to mange the symbol. The file format is different and it is hard to share the symbol between every kind of GIS software. In addition, the GIS software abroad can not satisfy for the cartographic desire in our country, and it lacks a more unified system design standards of symbol.So, for the present development status of symbol libraries, it is urgent todevelop uniform design standards for cartographic symbol library. According tothe request of the cartographic symbols in Chinese cartography, we should take the way of the database symbols to mange the symbol uniformly. Thus, thegeneral requirement of the symbol unified between the GIS software and the GIS users can be solved. When designing the cartographic symbol database, we take the way of data model of GIS to manage the symbol-the graphic and the attribute stored separately. In this way it not only can make the graphic and the attributes independently, but also can make those to become the whole entirety.