Rect::CheckedSize

inline Size<T> CheckedSize() const;

CheckedSize returns the width and height of the local rectangle. If the coordinates are non-normal, the width will be stored as zero and the height will be stored as zero. 

Note 

The width of a rectangle is determined by the equation: x2 - x1, and the height by the equation: y2 - y1.

A Size value representing the width and height of the local rectangle in the form of a Size.