From 1d1a30610226ffdb296e6ceb986b3fe0298f2158 Mon Sep 17 00:00:00 2001
From: amwaterhouse <Andrew Waterhouse>
Date: Mon, 18 Apr 2005 08:04:44 +0000
Subject: [PATCH] fastPaint modified incase scroll is more than page size

---
 src/jalview/gui/IdCanvas.java |   19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/src/jalview/gui/IdCanvas.java b/src/jalview/gui/IdCanvas.java
index f1ab981..6c50f31 100755
--- a/src/jalview/gui/IdCanvas.java
+++ b/src/jalview/gui/IdCanvas.java
@@ -56,16 +56,23 @@ public class IdCanvas extends JPanel
     gg.copyArea( 0,0, getWidth(), imgHeight, 0, -vertical*av.charHeight );
 
     int ss=av.startSeq, es=av.endSeq, transY = 0;
-     if(vertical>0)    // scroll down
+    if (vertical > 0) // scroll down
      {
-       transY = imgHeight - vertical*av.charHeight;
        ss = es - vertical;
+       if(ss<av.startSeq) // ie scrolling too fast, more than a page at a time
+         ss = av.startSeq;
+       else
+         transY = imgHeight - vertical * av.charHeight;
      }
-     else if(vertical<0)
+     else if (vertical < 0)
      {
-       es = ss-vertical;
+       es = ss - vertical;
+       if(es > av.endSeq)
+         es = av.endSeq;
      }
 
+
+
         gg.translate(0, transY);
 
         drawIds(ss, es);
@@ -84,8 +91,8 @@ public class IdCanvas extends JPanel
 
     if (fastPaint)
     {
-      g.drawImage(image, 0, 0, this);
       fastPaint = false;
+      g.drawImage(image, 0, 0, this);
       return;
     }
 
@@ -109,11 +116,9 @@ public class IdCanvas extends JPanel
 
   void drawIds(int starty, int endy)
   {
-
     Color currentColor     = Color.white;
     Color currentTextColor = Color.black;
 
-
     if (av.getWrapAlignment())
     {
 
-- 
1.7.10.2