JAL-2609 process only up to end of alignment when shifting sequences

diff --git a/src/jalview/gui/SeqCanvas.java b/src/jalview/gui/SeqCanvas.java
index 12b426d..576d6ca 100755 (executable)
--- a/src/jalview/gui/SeqCanvas.java
+++ b/src/jalview/gui/SeqCanvas.java
@@ -1505,8 +1505,15 @@ public class SeqCanvas extends JComponent implements ViewportListenerI
     {
       visibleWidths++;
     }
-    // todo limit visibleWidths to not exceed width of alignment
-    // (don't process white space below)
+    /*
+     *  limit visibleWidths to not exceed width of alignment
+     */
+    int maxWidths = (xMax - ranges.getStartRes()) / viewportWidth;
+    if (xMax % viewportWidth > 0)
+    {
+      maxWidths++;
+    }
+    visibleWidths = Math.min(visibleWidths, maxWidths);
 
     if (positions > 0)
     {