virtualbox.org

Hi,
I found that after taking a screenshot in a game played on a virtual machine it copies black screen to clipboard.
I use Windows XP as a guest system and I installed direct 3d support.
Is there any way to fix it?

How did you take the screenshot? Have you tried using the snipping tool in the host OS to capture the screen of the vm to the host's clipboard?

The only way to fix it AFAIK is to disable 3D support.

What you are seeing is the result of using a graphic overlay. That means that the PC's standard graphics UI just sets aside a rectangle of screen space, often painted a special color for easy ID (same idea as "green screen" in movies) and the high end graphics stuff composits into that without the high res motion graphics data having to cross the slow PC data bus several times. And since the overlay video data never enters the PC, the PC can't capture it.

If there's no overlay feature then it all has to be rendered and composited in software by the PC's standard CPU. So, disable 3D and you'll be able to grab screenshots, but of course the game will be crippled, or perhaps just refuse to run at all...

BillG wrote:How did you take the screenshot? Have you tried using the snipping tool in the host OS to capture the screen of the vm to the host's clipboard?

I used print screen button on virtual machine. It works your way, but I want to take screenshots automatically on virtual machine, so it won't help me.

mpack wrote:The only way to fix it AFAIK is to disable 3D support.

What you are seeing is the result of using a graphic overlay. That means that the PC's standard graphics UI just sets aside a rectangle of screen space, often painted a special color for easy ID (same idea as "green screen" in movies) and the high end graphics stuff composits into that without the high res motion graphics data having to cross the slow PC data bus several times. And since the overlay video data never enters the PC, the PC can't capture it.

If there's no overlay feature then it all has to be rendered and composited in software by the PC's standard CPU. So, disable 3D and you'll be able to grab screenshots, but of course the game will be crippled, or perhaps just refuse to run at all...

Thanks for info. After disabling 3D supporty game doesn't work, so I guess that currently there is no way of screenshoting on VB machine.
Do you think that Oracle will fix it in the future?

Packamos wrote:Do you think that Oracle will fix it in the future?

No, I wouldn't think so. It's a feature of how overlay graphics work.

I finally got it working on VMware Player virtual machine. So it is possible!

VMPlayer is a different platform with its own implementation of virtual hardware. If you got a screen grab to work on VMplayer then it isn't using overlay graphics, and I would expect it to have lower performance. Whether its performance on your PC is still good enough for some game, I wouldn't know.