hi there,
When the initial window size is specified through the function glutInitWindowSize( 1024, 768 ) for example, how should the objects be drawn in relation to this size? What is the relationship between these initial coordinates and the coordinates specified for each object in the world. Should be object coordinates be converted to window coordinates? 
thanks in advance
Just noticed that you didn’t get a reply so: when you position your object withing your clipping planes it will be scaled by OpenGL. If doing a frustum, make sure that the object is farther away than the near plane and closer than the far. The size of the near plane ( left,right,top & bottom ) should be appropriate for your object ( draw it out on graph paper ) and the windows (x,y) coordinates will vary, for a given object point, depending on the near plane’s size. Good luck,
Barry