Checking if euler is instance of THREE.Euler. Fixes #3737.

src/math/Matrix4.js

@@ -121,7 +121,7 @@ THREE.Matrix4.prototype = {
 
 	makeRotationFromEuler: function ( euler ) {
 
-		if ( typeof euler['order'] === undefined ) {
+		if ( euler instanceof THREE.Euler === false ) {
 
 			console.error( 'ERROR: Matrix\'s .makeRotationFromEuler() now expects a Euler rotation rather than a Vector3 and order.  Please update your code.' );
 
@@ -134,7 +134,7 @@ THREE.Matrix4.prototype = {
 		var c = Math.cos( y ), d = Math.sin( y );
 		var e = Math.cos( z ), f = Math.sin( z );
 
-		if ( euler.order === undefined || euler.order === 'XYZ' ) {
+		if ( euler.order === 'XYZ' ) {
 
 			var ae = a * e, af = a * f, be = b * e, bf = b * f;
 

src/math/Quaternion.js

@@ -112,7 +112,7 @@ THREE.Quaternion.prototype = {
 
 	setFromEuler: function ( euler, update ) {
 
-		if ( typeof euler['order'] === undefined ) {
+		if ( euler instanceof THREE.Euler === false ) {
 
 			console.error( 'ERROR: Quaternion\'s .setFromEuler() now expects a Euler rotation rather than a Vector3 and order.  Please update your code.' );
 		}
@@ -128,7 +128,7 @@ THREE.Quaternion.prototype = {
 		var s2 = Math.sin( euler._y / 2 );
 		var s3 = Math.sin( euler._z / 2 );
 
-		if ( euler.order === undefined || euler.order === 'XYZ' ) {
+		if ( euler.order === 'XYZ' ) {
 
 			this._x = s1 * c2 * c3 + c1 * s2 * s3;
 			this._y = c1 * s2 * c3 - s1 * c2 * s3;

src/math/Vector3.js

@@ -604,17 +604,17 @@ THREE.extend( THREE.Vector3.prototype, {
 
 	applyEuler: function () {
 
-		var q1 = new THREE.Quaternion();
+		var quaternion = new THREE.Quaternion();
+
+		return function ( euler ) {
 
-		return function ( rotation ) {
+			if ( euler instanceof THREE.Euler === false ) {
 
-			if( typeof rotation['order'] === undefined ) {
 				console.error( 'ERROR: Vector3\'s .applyEuler() now expects a Euler rotation rather than a Vector3 and order.  Please update your code.' );
-			}
 
-			var quaternion = q1.setFromEuler( rotation );
+			}
 
-			this.applyQuaternion( quaternion );
+			this.applyQuaternion( quaternion.setFromEuler( euler ) );
 
 			return this;