diff --git a/src/extras/helpers/WireframeHelper.js b/src/extras/helpers/WireframeHelper.js
index 301696e95ac183c8643356aef746f5e0b80e3312..6963c5972acb06b03490b7b0e99d1297b079714b 100644
--- a/src/extras/helpers/WireframeHelper.js
+++ b/src/extras/helpers/WireframeHelper.js
@@ -71,17 +71,23 @@ THREE.WireframeHelper = function ( object, hex ) {
 
 			var vertices = object.geometry.attributes.position.array;
 			var indices = object.geometry.attributes.index.array;
-			var offsets = object.geometry.offsets;
+			var drawcalls = object.geometry.drawcalls;
 			var numEdges = 0;
 
+			if ( drawcalls.length === 0 ) {
+
+				drawcalls = [ { count : indices.length, index : 0, start : 0 } ];
+
+			}
+
 			// allocate maximal size
 			var edges = new Uint32Array( 2 * indices.length );
 
-			for ( var o = 0, ol = offsets.length; o < ol; ++ o ) {
+			for ( var o = 0, ol = drawcalls.length; o < ol; ++ o ) {
 
-				var start = offsets[ o ].start;
-				var count = offsets[ o ].count;
-				var index = offsets[ o ].index;
+				var start = drawcalls[ o ].start;
+				var count = drawcalls[ o ].count;
+				var index = drawcalls[ o ].index;
 
 				for ( var i = start, il = start + count; i < il; i += 3 ) {