DOMPoint: w property
Note: This feature is available in Web Workers.
The DOMPoint interface's
w property holds the point's perspective value, w, for a
point in space.
Value
A double-precision floating-point value indicating the w perspective value for
the point. This value is unrestricted, meaning that it is allowed to be
infinite or invalid (that is, its value may be NaN or ±Infinity).
The default is 1.0.