JavaScript: window resize debouncing #snippet

resize-debounce.js

/* --------------------------------------------
 *         Detect device orientation
 *      and trigger changes based on it
   --------------------------------------------*/
function updateOrientation() {
	// Detect whether device supports orientationchange event, otherwise fall back to the resize event
	// Genius solution from http://stackoverflow.com/a/2307936
	var supportsOrientationChange = "onorientationchange" in window,
	    orientationEvent = supportsOrientationChange ? "orientationchange" : "resize",
	    newAngle, newOrientation;

	if(supportsOrientationChange){
		newAngle = window.orientation;
		switch(newAngle){
			case 0:
			case 180: newOrientation = 'portrait'; break;
			case 90:
			case -90: newOrientation = 'landscape'; break;
		}
	} else {
		if(document.width < document.height){
			newOrientation = 'portrait'
		} else {
			newOrientation = 'landscape'
		}
	}

	// Do the processing here

	/*
	 * Beautiful debouncing for resize event firing too much on the PC
	 * by Pim Jager http://stackoverflow.com/a/668185/930987
	 */
	resizeEvent = false;

	window.addEventListener(orientationEvent, function() {
		if(!resizeEvent) {
			clearTimeout(resizeEvent);
			resizeEvent = setTimeout(updateOrientation, 500) // half a second should be enough for a modern PC
		}
	})
}