一个有关三维GIS的ppt，也许对你开发三维GIS有帮助。-A related three-dimensional GIS-ppt, may be right there to help you develop three-dimensional GIS.

这是能强大的开源的功GIS应用开发库Virtual Terrain Project(VTP)的源代码，相对于收费昂贵的Skyline，VTP在诸多方面更具吸引力。若需完整编译源代码请仔细参考http://www.vterrain.org/Download/；VTP官方网站http://www.vterrain.org/-Source code of Virtual Terrain Project software suite, which is an open-source, powerful