diff --git a/diylc/diylc-core/src/org/diylc/presenter/DrawingManager.java b/diylc/diylc-core/src/org/diylc/presenter/DrawingManager.java
index 0b477a51..c7be2a65 100644
--- a/diylc/diylc-core/src/org/diylc/presenter/DrawingManager.java
+++ b/diylc/diylc-core/src/org/diylc/presenter/DrawingManager.java
@@ -251,7 +251,8 @@ public class DrawingManager {
     // apply zoom
     if (Math.abs(1.0 - zoom) > 1e-4) {
       g2dWrapper.scale(zoom, zoom);
-      visibleRect.setRect(visibleRect.getX() / zoom, visibleRect.getY() / zoom, 
+      if (visibleRect != null)
+        visibleRect.setRect(visibleRect.getX() / zoom, visibleRect.getY() / zoom, 
           visibleRect.getWidth() / zoom, visibleRect.getHeight() / zoom);
     }