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Hi, i need to developp an app which take screenshoot of Windows 3d games (DirectX,openGL).
I have made a Python app that take screenshoot but when i launch my app and for example Quake3 all my screenshoot are gray images.
So i wonder if i need to developp an DirectX app or not.
And if yes, how can i put a DirectX app in front of another DirectX app which is in fullscreen mode ?
Thx all

Why not just use the prtscr key?

Since graphics applications can and do trade-off between speed and the ability to allow screenshots, you might be in serious trouble. It is not always possible to get the exact contents of the screen back in memory, as that image does not exist. Rather, it is generated on the fly when sending data to the monitor.

Try alt+printscreen as suggested. If that does not work either, chances are likely you are looking at an side effect of the above.

If you're really really sure you want to hard-core screenshot opengl/directx programs, make a hook on the buffer swap command and take the contents after the swap. That should give you the content.