Windows Desktop Sharing API clipping area

Question

We evaluate using Windows Desktop Sharing API in our applications. It works fine but there is one problem: If we share only one application and the application client area ist covered partly by an other application, than the viewer sees only the none covered areas. The covered areas are black.

How can we avoid this? Is there a way to transmit the covered client area parts too?

Thanks for helping

Andreas

Answer 1

I will try to involve other senior engineer who is this aspect expert to help you.

Best wishes,

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Mike Zhang[MSFT]
MSDN Community Support | Feedback to us

Answer 2

AnRo wrote:

>

>We evaluate using Windows Desktop Sharing API in our applications. It works

>fine but there is one problem: If we share only one application and the

>application client area ist covered partly by an other application, than

>the viewer sees only the none covered areas. The covered areas are black.

>

>How can we avoid this? Is there a way to transmit the covered client area

>parts too?

 

If you're talking about pre-Windows 7, then the answer is NO.  The areas

that are covered simply do not exist, anywhere.  The "master" copy of the

desktop is the visible frame buffer that you see.  There is no hidden area

where the "real" window contents are stored.

--

Tim Roberts, [e-mail]

Providenza & Boekelheide, Inc.

 

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Tim Roberts, VC++ MVP Providenza & Boekelheide, Inc.

Answer 3

Hi Tim,

ok, but Microsoft Lync is able to make the hidden areas visible to the viewer (the remote site). I had evaluate this on a Vista computer. Additionaly, the Desktop Windows Manager API is able to generate thumpnails from any (not minimized) window including hidden areas.

That means, there must be a way to get the content of the whole window. The next question is, how is that method is combinable with the desktop sharing api?

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Andreas

Answer 4

AnRo wrote:

>

>ok, but Microsoft Lync is able to make the hidden areas visible to the

>viewer (the remote site). I had evaluate this on a Vista computer.

 

Maybe Lync installs a mirror display driver to track the window contents

themselves -- I don't know.

 

>Additionaly, the Desktop Windows Manager API is able to generate

>thumpnails from any (not minimized) window including hidden areas.

 

Desktop Window Manager owns the offscreen texture surfaces where the

windows draw their contents, and that feature ONLY works if you have Aero

Glass turned on.  Desktop sharing has to work whether Aero Glass is enabled

or not.

--

Tim Roberts, [e-mail]

Providenza & Boekelheide, Inc.

 

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Tim Roberts, VC++ MVP Providenza & Boekelheide, Inc.