Here how it's achievable using DirectComposition API
Russian: http://www.oszone.net/25395/
English: https://msdn.microsoft.com/magazine/dn745861.aspx
Basically what author does is
Sets WS_EX_NOREDIRECTIONBITMAP extended style to remove redirection bitmap of DWM. Content of window is now empty.
Creates DirectComposition device
Creates Composition SwapChain (and not hwnd swapchain)
Places one visual with SwapChain as content as root visual.
Renders into SwapChain using Direct2D API.
It also works well with WS_EX_TRANSPARENT | WS_EX_LAYERED | WS_EX_TOPMOST
for creating event-transparent overlays.