X-Git-Url: http://source.jalview.org/gitweb/?a=blobdiff_plain;f=src%2Fjalview%2Fviewmodel%2FOverviewDimensionsShowHidden.java;fp=src%2Fjalview%2Fviewmodel%2FOverviewDimensionsShowHidden.java;h=2216f33a150c5664ba8d570a3faa4bee5366692d;hb=5c41e4193f3bebb1c8e11c124a4928d1419b052c;hp=4b396a656efaa1c4332dc289906252c4acb0c3ba;hpb=eeabeb4f32b679c28eb7413b638a07035e0d7eb8;p=jalview.git

diff --git a/src/jalview/viewmodel/OverviewDimensionsShowHidden.java b/src/jalview/viewmodel/OverviewDimensionsShowHidden.java
index 4b396a6..2216f33 100644
--- a/src/jalview/viewmodel/OverviewDimensionsShowHidden.java
+++ b/src/jalview/viewmodel/OverviewDimensionsShowHidden.java
@@ -135,10 +135,12 @@ public class OverviewDimensionsShowHidden extends OverviewDimensions
     // so convert back after getting visible region position
     yAsSeq = hiddenSeqs.adjustForHiddenSeqs(hiddenSeqs
             .findIndexWithoutHiddenSeqs(yAsSeq));
+    yAsSeq = Math.max(yAsSeq, 0); // -1 if before first visible sequence
 
     // check in case we went off the edge of the alignment
     int visAlignHeight = hiddenSeqs.findIndexWithoutHiddenSeqs(alheight);
     int visYAsSeq = hiddenSeqs.findIndexWithoutHiddenSeqs(yAsSeq);
+    visYAsSeq = Math.max(visYAsSeq, 0); // -1 if before first visible sequence
     if (visYAsSeq + vpheight - 1 > visAlignHeight)
     {
       // went past the end of the alignment, adjust backwards
@@ -156,7 +158,6 @@ public class OverviewDimensionsShowHidden extends OverviewDimensions
     // update viewport
     ranges.setStartRes(visXAsRes);
     ranges.setStartSeq(visYAsSeq);
-
   }
 
   /**