Box3: Simplified setFromObject.

src/math/Box3.js

@@ -59,52 +59,34 @@ THREE.Box3.prototype = {
 		// Computes the world-axis-aligned bounding box of an object (including its children),
 		// accounting for both the object's, and children's, world transforms
 
-		var v1 = new THREE.Vector3();
+		var box;
 
 		return function ( object ) {
 
-			var scope = this;
+			if ( box === undefined ) box = new THREE.Box3();
 
-			object.updateMatrixWorld( true );
+			var scope = this;
 
 			this.makeEmpty();
 
+			object.updateMatrixWorld( true );
+
 			object.traverse( function ( node ) {
 
 				var geometry = node.geometry;
 
 				if ( geometry !== undefined ) {
 
-					if ( geometry instanceof THREE.Geometry ) {
-
-						var vertices = geometry.vertices;
-
-						for ( var i = 0, il = vertices.length; i < il; i ++ ) {
-
-							v1.copy( vertices[ i ] );
-
-							v1.applyMatrix4( node.matrixWorld );
+					if ( geometry.boundingBox === null ) {
 
-							scope.expandByPoint( v1 );
-
-						}
-
-					} else if ( geometry instanceof THREE.BufferGeometry && geometry.attributes[ 'position' ] !== undefined ) {
-
-						var positions = geometry.attributes[ 'position' ].array;
-
-						for ( var i = 0, il = positions.length; i < il; i += 3 ) {
-
-							v1.set( positions[ i ], positions[ i + 1 ], positions[ i + 2 ] );
-
-							v1.applyMatrix4( node.matrixWorld );
-
-							scope.expandByPoint( v1 );
-
-						}
+						geometry.computeBoundingBox();
 
 					}
 
+					box.copy( geometry.boundingBox ;
+					box.applyMatrix4( node.matrixWorld );
+					scope.union( box );
+
 				}
 
 			} );