gboolean gdk_rectangle_intersect ( const GdkRectangle* src1, const GdkRectangle* src2, GdkRectangle* dest )
Calculates the intersection of two rectangles.
It is allowed for
dest to be the same as either
If the rectangles do not intersect,
dest’s width and height is set
to 0 and its x and y values are undefined. If you are only interested
in whether the rectangles intersect, but not in the intersecting area