Visualization of complicated objects for hydraulic engineering based on OpenGL

Construction and visualization of three-dimensional (3D) complicated objects has become an important task in many GIS and their applications. Main process to construct a true 3D virtual scene with the programmable visualization environment OpenGL for water conservancy works is introduced. A simulation system developed by the authors is presented for importing, filtering and visualizing of complex geographical related data. Culling, lighting, shading and antialiasing were introduced to enhance the 3D visualization effects of the objects. Aspects like presentations of data with spatial dependence, virtual roaming in the terrain and geographical frame of reference and in time, interaction techniques are presented.