change coordinate system for 2D api

I’m trying to write a 2D app with custom visual components, etc. I’d like to be able to specify component coordinates in screen coordinate system (upper left is 0,0 and x grows towards right and y grows towards bottom). I tried to modify the modelview matrix by multiplying it by a modified identity matrix (y coord was -1 instead of 1 to inverse y coordinates) and then translating it by vector 0,480 (my screen height=480), but that didn’t work too well for some reason. If anyone has tried that could you please let me know how to go about it ? Or if you have any other ideas on how to make it easier…
Thank you,


Using a “2D window” is easy. You have to use the ortho view. For more information go to and take a loot at lesson 21 (“Lines, Antialiasing, Timing, Ortho View And Simple Sounds”).