If I use:
to set the ortho projection and if all of my coordinates for a GUI (2D overlays) are in the range of 0 to 1, and if I have a quad drawn on my (800,600) display at: (.0f0, 0.0f) (0.5f, 0.0f) (0.5f, 0.5f) 0.0f, 0.5f) will that quad be drawn starting at (400,300)? Or does the glOrtho command need the screen width and height? Hopefully this question makes sense! Thanks http://www.stodge.net - the powerhouse in personal commentary

I really suggest you to use the actual window height/width. That is very useful if you want mouse input...

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