I created a window using dwmextendframeintoclientarea, everything is ok except the top frame height is less than the value I settled while the window is maximized.
So the text drawn using drawthemetext will not align absolutly vertical center as following picture shows.
the first one is the caption bar while the window is normal size, while the second window is maximized.
It is because the height of the top frame actually is less than the value I setted in DwmExtendFrameIntoClientArea.
The problem is how could I get the real height of the top frame while dwm is enable and the window is maximized?