antialiasing and region problem

Hello,
I am not sure if this is a hardware issue, a windows issue, a gl issue, or a combination, so sorry if this is the wrong forum.

I have created a region from the image in the frame buffer and am able to set the region of the window to this no problem. It works and runs ok. The problem is that when I turn antialiasing on in the display properties, the window doesnt reshape properly.

With AA off, the window reshapes each frame to the image.

With AA on, it seems like the window only reshapes once, and then keeps the same shape. You can still see the animation going on in the background but because the window shape stays the same, it has the effect of looking through a cutout.

Basically, my render loop is like this…

drawscene

readpixels
createregion

SetWindowRgn
UpdateWindow

SwapBuffers

I also tried setting the windowrgn after the swapbuffers call in the hopes that maybe something didnt get finished.

Any thoughts on this issue/problem?

ps…running winxp with gf4mx

[This message has been edited by bumby (edited 06-12-2003).]