View Full Version : Anti-aliasing and glReadPixels(..GL_DEPTH_BUFFER...)

01-27-2004, 08:24 AM
Hi, I have a question I hope someone here can help me with. I would like to do the anti-aliasing after all the primitives and environment settings are done, but I would also like to get the depth value of a pixel on the screen by using glReadPixels(). And I'm not too sure I can do it because once it is anti-aliased I don't think a pixel my mouse is pointing at is still the original object.

But since I'm unexperienced with this I hope someone here can point me to the right direction.

Thanks in advance for any kind help.


01-28-2004, 02:43 AM
As the name implies glReadPixels works on pixels, not on fragments. You're not able to read the depth values from the multisample buffer with it.
The depth value xy-position you get is as exact as your screen (mouse coordinate) resolution. Subpixel exact depth picking doesn't sound useful.