Graphic System Based On User-defined Feature And Its Application In Pipe Net Modeling

With the development of graph modeling and computer technology, it is important to design a more universal, extendable, better maintainable graph modeling system with friendly graphic interface. Based on the idea of feature, a pipe net modeling system with user-defined feature is presented. The system is implemented with the OOP (Object Oriented Programming) technology, and the relationship between element and vector icon class is built.The pipe net modeling system of user-defined feature has two modules, including vector icon and pipe net modeling. Firstly, parametric uniform interpolation curve and three-point arc are built and their characteristics are analyzed in detail in this thesis. Then, based on user-defined feature, the vector icon is constructed by basic geometric elements, its attributes are set and the building process is given. Last, the pipe net modeling system is designed with OOP technology. Steps of building the pipe net modeling are described with the vector icon and a practical example is given. The main work finished in this thesis includes:(1) General basic graph elements. Besides the graph elements described in VC++, two new types of curves are constructed in the thesis, namely three-point arc and parametric uniform interpolation curve.(2) Vector icon system with user-defined feature is built and vector icon set is created. The vector icon set can be extended by users.(3) A feature pipe net modeling system is implemented. New modeling unit can be added into the system according to the user's requirement, and the modeling validity is maintained according to the predefined constraint conditions.Experiments show that the proposed pipe net modeling system is universal and extendable and the modeling efficiency can be improved.