Allow a number of influences per vertex other than 2

src/loaders/JSONLoader.js

@@ -417,15 +417,16 @@ THREE.JSONLoader.prototype.parse = function ( json, texturePath ) {
 	};
 
 	function parseSkin() {
+		var influencesPerVertex = ( json.influencesPerVertex !== undefined ) ? json.influencesPerVertex : 2;
 
 		if ( json.skinWeights ) {
 
-			for ( var i = 0, l = json.skinWeights.length; i < l; i += 2 ) {
+			for ( var i = 0, l = json.skinWeights.length; i < l; i += influencesPerVertex ) {
 
-				var x = json.skinWeights[ i     ];
-				var y = json.skinWeights[ i + 1 ];
-				var z = 0;
-				var w = 0;
+				var x =                               json.skinWeights[ i     ];
+				var y = ( influencesPerVertex > 1 ) ? json.skinWeights[ i + 1 ] : 0;
+				var z = ( influencesPerVertex > 2 ) ? json.skinWeights[ i + 2 ] : 0;
+				var w = ( influencesPerVertex > 3 ) ? json.skinWeights[ i + 3 ] : 0;
 
 				geometry.skinWeights.push( new THREE.Vector4( x, y, z, w ) );
 
@@ -435,12 +436,12 @@ THREE.JSONLoader.prototype.parse = function ( json, texturePath ) {
 
 		if ( json.skinIndices ) {
 
-			for ( var i = 0, l = json.skinIndices.length; i < l; i += 2 ) {
+			for ( var i = 0, l = json.skinIndices.length; i < l; i += influencesPerVertex ) {
 
-				var a = json.skinIndices[ i     ];
-				var b = json.skinIndices[ i + 1 ];
-				var c = 0;
-				var d = 0;
+				var a =                               json.skinIndices[ i     ];
+				var b = ( influencesPerVertex > 1 ) ? json.skinIndices[ i + 1 ] : 0;
+				var c = ( influencesPerVertex > 2 ) ? json.skinIndices[ i + 2 ] : 0;
+				var d = ( influencesPerVertex > 3 ) ? json.skinIndices[ i + 3 ] : 0;
 
 				geometry.skinIndices.push( new THREE.Vector4( a, b, c, d ) );