View Full Version : Offscreen drawing

09-29-2006, 01:29 PM
I want to create a hidden window and use it to draw a temporary image, for projected object shadows. I need a separate context, because I want the object shadows to be antialiased, regardless of what the main viewport antialias setting is. The model is drawn from the angle of the light, then I use glreadpixels to copy the resulting image into a texture, which then gets projected onto walls and floors.

Should this be done with an FBO? If so, how do I start? The examples I have read aren't exactly straightforward.

09-29-2006, 04:15 PM
Yes, use FBO. I think hidden window won't work because pixel ownership issues (a window probably needs to be on screen and visible. Parts outside desktop or covered by other windows may have undefined data)

Look at the spec "Usage Examples"

09-29-2006, 04:16 PM
you could find the fbo paper on http://www.ati.com/developer

09-30-2006, 12:01 PM
Is anyone available on Skype? I can be found under "Leadwerks".