A 3D realistic image is a core technique of scientific visualization

computer animation

and virtual reality

and an important technique of spatio temporal GIS. OpenGL is the current international standard of 3D image. This article discussed the implementing method for the representation of terrain realistic image based on OpenGL

such as the digital terrain model mapping

the blend of remote sensing image and terrain data

the blend of thematic information and terrain data

animation

virtual reality

and etc.The mapping methods respective to the DTM format such as TIN

GRID and Contour

the direct and indirect blending methods of remote sensing image and terrain data

and the blending method of thematic information and terrain data based on the 2D transparent texture were presented mainly. Based on aforementioned methods

a flood routing visualization system for Jingjing diversion area was developed and the results fit the anticipant goals well.