X-Git-Url: http://source.jalview.org/gitweb/?p=jalview.git;a=blobdiff_plain;f=src%2Fjalview%2Fgui%2FScalePanel.java;h=6abee0882b7b8a31e230e64735c5c5ff549b4b1e;hp=e6bba0249677a351fda2ba24b41333f521e95b11;hb=9062c3dbd065631f01af61f47a8cbafabe9c6c8b;hpb=698646a270bc76f9a68d81f72fbaed80d4384c41

diff --git a/src/jalview/gui/ScalePanel.java b/src/jalview/gui/ScalePanel.java
index e6bba02..6abee08 100755
--- a/src/jalview/gui/ScalePanel.java
+++ b/src/jalview/gui/ScalePanel.java
@@ -276,7 +276,9 @@ public class ScalePanel extends JPanel
   {
     mouseDragging = false;
 
-    int res = (evt.getX() / av.getCharWidth())
+    int xCords = Math.max(0, evt.getX()); // prevent negative X coordinates
+
+    int res = (xCords / av.getCharWidth())
             + av.getRanges().getStartRes();
 
     if (av.hasHiddenColumns())