Any application running on Windows Vista, with DWM/Aero enabled, is
composited, without the application having to make any calls. You don't
have to select any special formats.
You will notice that the application gets the glass looking borders, has
live previews in Alt-Tab and taskbar thumbnails, and its contents show up in
Flip3D. This is indeed done by using a shared surface, between Direct3D and
the DWM.
Perhaps you were after having the application content "blended" with the
desktop's background, like windowless controls? If that was the feature you
were after, that is not something that is enabled by the DWM.
-Pablo
"Chris Hill" <Chris244@aol.com> wrote in message
news:44977056.1939240651@msnews.microsoft.com...
> On Mon, 19 Jun 2006 14:09:07 GMT, Chris244@aol.com (Chris Hill) wrote:
>>>> Can windowed Direct 3D and/or OpenGL rendering be composited with the
>>>> desktop using the alpha channel generated using those APIs?
>>>
>>>Yes, that would happen automatically.
>>
>>Excellent. I'll write a Direct3D app to test this. You're saying I
>>don't need to call any API to make this happen, the client area of my
>>window will automatically be composited with the desktop if I am using
>>an alpha enabled buffer format?
>
> I tried it an it didn't work. Do I need to use a particular version
> of Direct3D or make a special D3D call? Is there a flag I need to set
> on the window or an API call I need to make so that Direct3D knows
> that I want it to composite with the desktop? I thought there might
> be some special setup required, but I haven't been able to find any
> documentation about the subject.
>
> The blog entry seems to indicate that DirectX will handle the
> communication with the DWM to configure a shared surface (and that I
> don't need to do anything special to get a shared surface).
>
> Is there a sample available of a desktop compositing Direct3D
> application?
>
> Chris