This function is implemented by FrameXML in FrameXML/UIParent.lua.

Determines whether or not the mouse is over the specified frame.

isOver = MouseIsOver(frame, topOffset, bottomOffset, leftOffset, rightOffset);

Parameters Edit

Arguments Edit

(frame, [topOffset, bottomOffset, leftOffset, rightOffset])

frame 

Frame - The frame (or frame-derived object such as Buttons, etc) to test with

topOffset 

(optional) Number - distance from the top to include in calculations

bottomOffset 

(optional) Number - distance from the bottom to include in calculations

leftOffset 

(optional) Number - distance from the left to include in calculations

rightOffset 

(optional) Number - distance from the right to include in calculations

Returns Edit

isOver 

Boolean - A true value if the mouse is over the frame, false otherwise.

Example Edit

You can determine whether or not the mouse is over the minimap using the below.

if (MouseIsOver(MinimapCluster)) then
   -- do something
end

Details Edit

It doesn't matter if the frame is hidden or not, if the mouse would be over it when you :Show() it then this function does return true.

Most importantly, it will still return true if the frame in question has its mouse response disabled using EnableMouse(false). Hence, MouseIsOver is what you need for rollover effects not interfering with the player's world clicks.