Display texture according to the camera position (fake reflections/glass demo)

On this thread: http://blenderartists.org/forum/showthread.php?t=11430 you can find the Blengine’s old demo files, one of them (glass) shows a glass textured, and the texture displays according to the camera position, i want to know how to do that… i could not find where is the adjustment and i think it’s a good feature to fake lightweight reflections, and it works even without GLSL.

Thank you.

Nevermind!
UV/Image Editor Cell>>Image>>Realtime Texture Mapping>>Reflection

Thanks.