dist/picturefill.js
function updateMetrics() {

		isVwDirty = false;
		DPR = window.devicePixelRatio;
		cssCache = {};
		sizeLengthCache = {};

		pf.DPR = DPR || 1;

		units.width = Math.max(window.innerWidth || 0, docElem.clientWidth);
		units.height = Math.max(window.innerHeight || 0, docElem.clientHeight);

		units.vw = units.width / 100;
		units.vh = units.height / 100;

		evalId = [ units.height, units.width, DPR ].join("-");

		units.em = pf.getEmValue();
		units.rem = units.em;
	}
function updateMetrics() {

		isVwDirty = false;
		DPR = window.devicePixelRatio;
		cssCache = {};
		sizeLengthCache = {};

		pf.DPR = DPR || 1;

		units.width = Math.max(window.innerWidth || 0, docElem.clientWidth);
		units.height = Math.max(window.innerHeight || 0, docElem.clientHeight);

		units.vw = units.width / 100;
		units.vh = units.height / 100;

		evalId = [ units.height, units.width, DPR ].join("-");

		units.em = pf.getEmValue();
		units.rem = units.em;
	}
function updateMetrics ( ) { isVwDirty = false ; DPR = window . devicePixelRatio ; cssCache = { } ; sizeLengthCache = { } ; pf . DPR = DPR || 1 ; units . width = Math . max ( window . innerWidth || 0 , docElem . clientWidth ) ; units . height = Math . max ( window . innerHeight || 0 , docElem . clientHeight ) ; units . vw = units . width / 100 ; units . vh = units . height / 100 ; evalId = [ units . height , units . width , DPR ] . join ( "-" ) ; units . em = pf . getEmValue ( ) ; units . rem = units . em ; }
updates the internal vW property with the current viewport width in px
updates the internal vW property with the current viewport width in px