From b836aae53d015cbbac0da38920299d075c874a95 Mon Sep 17 00:00:00 2001
From: kiramt <k.mourao@dundee.ac.uk>
Date: Wed, 16 Aug 2017 12:20:16 +0100
Subject: [PATCH] JAL-2665 fix resize

---
 src/jalview/gui/SeqCanvas.java |   60 +++++++++++++++++++++++++---------------
 1 file changed, 37 insertions(+), 23 deletions(-)

diff --git a/src/jalview/gui/SeqCanvas.java b/src/jalview/gui/SeqCanvas.java
index 3626383..6f63dd6 100755
--- a/src/jalview/gui/SeqCanvas.java
+++ b/src/jalview/gui/SeqCanvas.java
@@ -296,8 +296,9 @@ public class SeqCanvas extends JComponent implements ViewportListenerI
     int transX = 0;
     int transY = 0;
 
-    gg.copyArea(horizontal * charWidth, vertical * charHeight, imgWidth,
-            imgHeight, -horizontal * charWidth, -vertical * charHeight);
+    gg.copyArea(horizontal * charWidth, vertical * charHeight,
+            img.getWidth(), img.getHeight(), -horizontal * charWidth,
+            -vertical * charHeight);
 
     if (horizontal > 0) // scrollbar pulled right, image to the left
     {
@@ -318,7 +319,7 @@ public class SeqCanvas extends JComponent implements ViewportListenerI
       }
       else
       {
-        transY = imgHeight - ((vertical + 1) * charHeight);
+        transY = img.getHeight() - ((vertical + 1) * charHeight);
       }
     }
     else if (vertical < 0)
@@ -360,15 +361,6 @@ public class SeqCanvas extends JComponent implements ViewportListenerI
     // selectImage will hold any selection we have
     // lcimg is a local *copy* of img which we'll draw selectImage on top of
 
-    if (img == null)
-    {
-      setupImage();
-    }
-    if (img == null)
-    {
-      return;
-    }
-
     BufferedImage selectImage = drawSelectionGroup();
 
     if (fastPaint || (getVisibleRect().width != g.getClipBounds().width)
@@ -380,6 +372,29 @@ public class SeqCanvas extends JComponent implements ViewportListenerI
       fastPaint = false;
       return;
     }
+
+    int width = getWidth();
+    int height = getHeight();
+
+    width -= (width % charWidth);
+    height -= (height % charHeight);
+
+    if ((width < 1) || (height < 1))
+    {
+      return;
+    }
+
+    if (img == null || width != img.getWidth() || height != img.getHeight())
+    {
+      img = setupImage();
+      gg = (Graphics2D) img.getGraphics();
+      gg.setFont(av.getFont());
+    }
+    if (img == null)
+    {
+      return;
+    }
+
     
     if (av.antiAlias)
     {
@@ -388,7 +403,7 @@ public class SeqCanvas extends JComponent implements ViewportListenerI
     }
     
     gg.setColor(Color.white);
-    gg.fillRect(0, 0, imgWidth, imgHeight);
+    gg.fillRect(0, 0, img.getWidth(), img.getHeight());
     
     ViewportRanges ranges = av.getRanges();
     if (av.getWrapAlignment())
@@ -435,21 +450,20 @@ public class SeqCanvas extends JComponent implements ViewportListenerI
     repaint();
   }
 
-  private void setupImage()
+  /*private void setupImage()
   {
     // this draws the whole of the alignment
     imgWidth = getWidth();
     imgHeight = getHeight();
-
+  
     imgWidth -= (imgWidth % charWidth);
     imgHeight -= (imgHeight % charHeight);
-
+  
     if ((imgWidth < 1) || (imgHeight < 1))
     {
       return;
     }
-
-
+  
       try
       {
       img = new BufferedImage(imgWidth, imgHeight,
@@ -461,13 +475,13 @@ public class SeqCanvas extends JComponent implements ViewportListenerI
         System.gc();
         System.err.println("SeqCanvas OutOfMemory Redraw Error.\n" + er);
         new OOMWarning("Creating alignment image for display", er);
-
+  
       return;
       }
+  
+  }*/
 
-  }
-
-  private BufferedImage setupSelectionImage()
+  private BufferedImage setupImage()
   {
     BufferedImage lcimg = null;
 
@@ -1056,7 +1070,7 @@ public class SeqCanvas extends JComponent implements ViewportListenerI
   private BufferedImage drawSelectionGroup()
   {
     // get a new image of the correct size
-    BufferedImage selectionImage = setupSelectionImage();
+    BufferedImage selectionImage = setupImage();
 
     if (selectionImage == null)
     {
-- 
1.7.10.2