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07-10-2001, 02:36 AM
i use glut for mouse, when i get x,y coords by pressing mouse button and it should place a point in there but it doesn't how can i convert the given coords to screen coords?

07-11-2001, 08:26 AM
The GLUT mouse function returns X and Y coordinates for the click (these are screen coordinates it returns) to convert these to GLUT and consequently openGL coordinates you need to flip the Y axis. Screen coordinates start from the top left, but openGL coordinates start at the _lower_ left corner.
so just do this with the coordinates the mouse down function returns

y = wh - y; // "wh" is the height of your GLUT window.

Hope this helps

Rob The Bloke
07-12-2001, 04:45 PM
Unless of course you want to put that point into 3D space in which case you'll have to use gluUnProject() and some nasty math