ScaleMarkerOnOpen.js

jQuery(function($){

	var lastMarkerId = false;
	var scaleMultiplier = 1.3;

	$(document.body).on('infowindowopen.wpgmza', function(e){
		var tmarkid = e.target.mapObject.id;
	    var tmapid = e.target.mapObject.map_id;

	    if(lastMarkerId !== tmarkid){

	    	var lastMark = WPGMZA.getMapByID(tmapid).getMarkerByID(lastMarkerId);
	    	if(lastMark !== null){
	    		lastMark.updateIcon();
	    	}

	    	lastMarkerId = tmarkid;

	    	var tmark = WPGMZA.getMapByID(tmapid).getMarkerByID(tmarkid);
	    	
			var icon = tmark.getIcon();
			
			if(icon && icon.url){
				icon.url = icon.url.replace(/^http(s?):/, "");
			
				var img = new Image();
				img.onload = function(event) {
					var autoDetect = false;
					var size;

					if(tmark.retina == 1){
						if(!autoDetect){
							size = new google.maps.Size(
								WPGMZA.settings.retinaWidth ?  Math.round( parseInt(WPGMZA.settings.retinaWidth) * scaleMultiplier) : Math.round( (img.width / 2) * scaleMultiplier),
								WPGMZA.settings.retinaHeight ?  Math.round( parseInt(WPGMZA.settings.retinaHeight) * scaleMultiplier) : Math.round( (img.height / 2) * scaleMultiplier)
							);
						} else {
							size = new google.maps.Size(
								Math.round( (img.width / 2) * scaleMultiplier),
								Math.round( (img.height / 2) * scaleMultiplier)
							);
						}
					} else {
						size = new google.maps.Size(
							Math.round( (img.width) * scaleMultiplier),
							Math.round( (img.height) * scaleMultiplier)
						);
					}
					
						
					tmark.googleMarker.setIcon(
						new google.maps.MarkerImage(icon.url, null, null, null, size)
					);
					
				};
				
				img.src = icon.url;
			}
		}
	});	
});