Shuffle layers

Author: thealexus

shuffleSelected.jsx

@@ -0,0 +1,109 @@
+/*
+Shuffles all selected layers. If none layers selected. shuffles all layers in comp
+
+CC-BY, Alex Kravchenko, 2016
+*/
+
+var shuffleLayers = this;
+
+shuffleLayers.shuffle = function(arr) 
+	{
+		for (var i = arr.length; i; i--) 
+			{
+				var j = Math.floor(Math.random() * i);
+				var x = arr[i - 1];
+				arr[i - 1] = arr[j];
+				arr[j] = x;
+			}
+	}
+
+shuffleLayers.getActiveComp = function()
+	{
+		var myComp = app.project.activeItem;
+		if(!myComp)
+			return null;
+		if(!(myComp instanceof CompItem))
+			return null;
+		return myComp;
+	}
+
+shuffleLayers.start = function()
+	{
+		app.beginUndoGroup("Shuffle Layers");
+		var myComp = shuffleLayers.getActiveComp();
+		if(!myComp)
+			{
+				alert("Please open composition");
+				return 0;
+			}
+
+		//get all selected layers
+		var selLayers = [];
+		if(myComp.selectedLayers.length == 0)
+			for(var i=1; i<=myComp.numLayers;i++)
+				selLayers.push(myComp.layer(i));
+		else
+			for(var i=0; i<myComp.selectedLayers.length;i++)
+				selLayers.push(myComp.selectedLayers[i]);
+
+		//order selected layers by index
+		var flag = true;
+		while(flag)
+			{
+				flag = false;
+				for(var i=0;i<selLayers.length-1;i++)
+					if(selLayers[i].index > selLayers[i+1].index)
+						{
+							flag = true;
+							var x = selLayers[i];
+							selLayers[i] = selLayers[i+1];
+							selLayers[i+1] = x;
+						}
+			}
+
+		//save original indexes, to put layers back there later
+		var oldIndexes = [];
+		for(var i=0;i<selLayers.length;i++)
+			oldIndexes.push(selLayers[i].index);
+		
+		//shuflle selected layers 
+		shuffleLayers.shuffle(selLayers);
+		
+		//$.bp();
+
+		//put all layers to the bottom of the comp, to avoid interference
+		for(var i=0;i<selLayers.length;i++)
+			{
+				var curLayer = selLayers[i];
+				var locked = curLayer.locked;
+				curLayer.locked = false;
+				curLayer.moveToEnd();
+				curLayer.locked = locked;
+			}
+
+		//put shuffled layers back to old indexes
+		for(var i=0;i<selLayers.length;i++)
+			{
+				var curLayer = selLayers[i];
+				var newIndex = oldIndexes[i];
+				var locked = curLayer.locked;
+
+				curLayer.locked = false;
+
+				if(newIndex == 1)
+					{
+						//$.writeln("Gonna move " + curLayer.index+" to the top");
+						curLayer.moveToBeginning();
+					}
+				else
+					{
+						//$.writeln("Gonna move " + curLayer.index+" after " + myComp.layer(newIndex-1).index);
+						curLayer.moveAfter(myComp.layer(newIndex-1));
+					}
+				curLayer.locked = locked;
+			}
+
+		app.endUndoGroup();
+	}
+
+shuffleLayers.start();