Vc + + Based Gis Vector Graphics System Design And Implementation

Vector graphic system which is oriented geographic objects is a main way for the geographical entities abstract and complete expression. Therefore, it is an important component of GIS system, also a focus in the development of GIS system.This thesis relies on "Pingle tourist information platform" subject, aimed to develop a vector graphic system independently that can meet the needs of the information platform. In this paper, the solution that developing a GIS vector graphic system from the bottom using VC++ is brought forward On the basis of study for the current status of the development of vector graphic system. And then explore the organizational structure of the spatial data associated with the system, the design, implementation techniques, functional structure of the system and so on are introduced and analyzed in this paper.In this paper, the organization and storage of the vector graphic data object class is completed by object-oriented approach, drawing and symbolization of graphical objects are achieved. The establishment of coordinate system of the vector graphic and the conversion relationship between this coordinate and Windows coordinate system is explored. And based on this, operating functions such as stepless zoom and pan are achieved. Two-way query between graphic objects and attribute information is completed by operating attributes data files and connecting to attribute database. Layer management window is developed with VC++ tree control, and then graphic show on view is controlled through layer management. At the same time the display speed of vector graphic and other issues are discussed and solution is proposed. Finally, the research results of this thesis are applied to Pingle tourism information platform, and achieved the desired effects. Conclusion indicates that, the system achieved in this paper has some flexibility, class and functions required can be added at any time, good in scalability.