TrackballControls: Added event.preventDefault() in touchstart. See mrdoob#14182

Author: mrdoob

examples/js/controls/TrackballControls.js

@@ -492,6 +492,8 @@ THREE.TrackballControls = function ( object, domElement ) {
 	function touchstart( event ) {
 
 		if ( _this.enabled === false ) return;
+		
+		event.preventDefault();
 
 		switch ( event.touches.length ) {