用IDL4.5写的三维地形显示的IDL代码，里面自带数据，有些基本的菜单、工具条、状态栏，用面向对象的思想写的，对初学者应该很有用-IDL4.5 written by three-dimensional topographical display IDL code, which bring their own data, some basic menu, toolbar, status bar, using object-oriente