JAL-2721 no fastPaint if img has been nulled by fontChanged!

diff --git a/src/jalview/gui/SeqCanvas.java b/src/jalview/gui/SeqCanvas.java
index 191a7d8..4e896a0 100755 (executable)
--- a/src/jalview/gui/SeqCanvas.java
+++ b/src/jalview/gui/SeqCanvas.java
@@ -283,7 +283,7 @@ public class SeqCanvas extends JComponent implements ViewportListenerI
    */
   public void fastPaint(int horizontal, int vertical)
   {
-    if (fastpainting || gg == null)
+    if (fastpainting || gg == null || img == null)
     {
       return;
     }