Merge pull request #13840 from WestLangley/dev-matrixAutoUpdate

Honor matrixAutoUpdate flag in serialization

src/core/Object3D.js

@@ -661,6 +661,8 @@ Object3D.prototype = Object.assign( Object.create( EventDispatcher.prototype ),
 
 		object.matrix = this.matrix.toArray();
 
+		if ( this.matrixAutoUpdate === false ) object.matrixAutoUpdate = false;
+
 		//
 
 		function serialize( library, element ) {

src/loaders/ObjectLoader.js

@@ -795,10 +795,13 @@ Object.assign( ObjectLoader.prototype, {
 		object.uuid = data.uuid;
 
 		if ( data.name !== undefined ) object.name = data.name;
+
 		if ( data.matrix !== undefined ) {
 
 			object.matrix.fromArray( data.matrix );
-			object.matrix.decompose( object.position, object.quaternion, object.scale );
+
+			if ( data.matrixAutoUpdate !== undefined ) object.matrixAutoUpdate = data.matrixAutoUpdate;
+			if ( object.matrixAutoUpdate ) object.matrix.decompose( object.position, object.quaternion, object.scale );
 
 		} else {