Orthographic: clipping a region

[{MSX}]

Hi! I'm doing some rendering in glOrtho mode
I was wondering, how can draw something in a way that only things inside a given rectangle are really drawn ?
Something like clipping.

Thanks !

[Paulius]

You can specify clip planes with glClipPlane, but a much more universal way would be to draw the form you want clipping against in the stencil buffer and then use stencil testing while drawing.

[siim]

Also after setting up the clip plane with glClipPlane you can use glEnable(GL_CLIP_PLANE#)/glDisable(GL_CLIP_PLANE#) for quick switching.