Detect when mouse leaves program window

[TerryRitchie]

Something strange happens with your code @Dav . The mouse is detected as out before the cursor leaves the bottom of the window. The strip being missed at the bottom appears to be the exact same height as the title bar. The title bar height of the window may need to be obtained as well to compensate.

The mouse pointer is still shown within bounds while it's in the title bar, which is technically correct. The y value needs to be adjusted by the height of the title bar to remove the dead strip at the bottom and to remove the title bar area from the equation, showing the mouse only within the working area of the window.

Solve one hurdle only to introduce another, LOL. I love programming.