Possible to have a window where mouse clicks go through it?

Question

On Microsoft Windows, is it possible to have a click through window (where all mouse clicks will go straight through), similar to WS_EX_TRANSPARENT, without the redrawing issues that WS_EX_TRANSPARENT has?

I am not talking about a layered window, but a fully opaque window where all clicks just go through to the item beneath.

Thanks!

Answer 1

handle WM_NCHITTEST and return HTTRANSPARENT

Answer 2

Also, SetLayeredAttribute can kill mouse events.