Program design theory of mine ventilation visualization

According to the characteristic of mine ventilation, tunnel is the core of entire mine ventilation, the composing of mine ventilation system visualization is designed in the base of tunnel. The mine ventilation visualization has position data(vector data) and attribute data that is relevant for the mine ventilation . A new program was developed by using object-oriented method and database is used for storing attribute data, in this method, a base class is designed for all visualization object class , in this class a database pointer is encapsulated, so it can keep graph and database consistent .At this software, it has resolve joint position drawing by using the double line to draw tunnel and build topology relationship automatically.