Editor: container.dom.offset* is not available at construction time.

editor/js/Viewport.js

@@ -26,7 +26,7 @@ var Viewport = function ( editor ) {
 
 	//
 
-	var camera = new THREE.PerspectiveCamera( 50, container.dom.offsetWidth / container.dom.offsetHeight, 1, 5000 );
+	var camera = new THREE.PerspectiveCamera( 50, 1, 1, 5000 );
 	camera.position.fromArray( editor.config.getKey( 'camera' ).position );
 	camera.lookAt( new THREE.Vector3().fromArray( editor.config.getKey( 'camera' ).target ) );