No thumbnails showing in Aero flip/thumbnail for full screen direct3d 9 application

Question

I'm sure this is on the web somewhere, but I'm having trouble with the search terms (getting lots of non-relevant stuff.) Anyway, I've got a Direct3D9 application. When it runs in full screen, on Vista and Windows 7, and you hit Alt-Tab or Win-Tab, my application just shows up blank in the thumbnail/preview/live view (not sure of the correct term.) Is there an API or notification I can respond to where I can draw my backbuffer to the thumbnail?

Answer 1

When running a full-screen Direct3D application window compositing (of which the thumbnails are a part) is disabled. This is typically a good thing, since it can increase performance of the full-screen app. As a default this behavior is reasonable since most full-screen apps (especially those developed against XP or earlier) expect to be the sole focus of the user while the app is running. You can manually instantiate and update your thumbnail in this case if you wish, but alt-tabbing away from a full-screen app is usually and edge case.

For more information about compositing in general, including overviews of the thumbnail APIs, check out this MSDN article