diff --git a/src/kiri-mode/cam/topo.js b/src/kiri-mode/cam/topo.js
index 06db0ba6..c54e349f 100644
--- a/src/kiri-mode/cam/topo.js
+++ b/src/kiri-mode/cam/topo.js
@@ -74,7 +74,8 @@
                 debug_clips = debug && true,
                 debug_topo = debug && true,
                 debug_topo_lines = debug && true,
-                debug_topo_shells = debug && true;
+                debug_topo_shells = debug && true,
+                time = Date.now;
 
             if (tolerance == 0) {
                 console.log(`contour auto tolerance`,resolution.round(4));