[IDEA] Add samples for Windows.UI.Composition

[reflectronic]

Windows.UI.Composition is a library that exposes the API for the system's composition engine. It provides support for creating, animating, and applying effects to visual elements. This issue suggests adding a couple of samples to demonstrate use of the native Composition interop APIs, which allow support for drawing to Win32 HWNDs and DirectX interop.

[msmshazan]

Effecient Alpha Blended windows would be a good sample too https://web.archive.org/web/20190913214618/http://www.pjblewis.com/site/posts/2016-04-27-p2-efficient-alpha-blended-windows-directcomposition.html

[sylveon]

This isn't the same. Windows.UI.Composition is a different API than DirectComposition, although in this case both can achieve the desired characteristic of a transparent window.

[reflectronic]

Perhaps this issue could be extended to adding samples for both; since DirectComposition is actually a native API, there is a lot more to demonstrate usage of TerraFX with (as opposed to just a few interop interfaces).