X-Git-Url: http://source.jalview.org/gitweb/?a=blobdiff_plain;ds=sidebyside;f=src%2Fjalview%2Fgui%2FIdCanvas.java;h=6c50f31c69535d35b5afd94f84564253b9c16794;hb=e7ed63f1ea56432246a6ed1553f0fe56d26f56ea;hp=959c83c28264a1a1bc73219b2d3958a0e4483cf2;hpb=c3162a6dd5f226c743bce629cf125a17c9b67711;p=jalview.git

diff --git a/src/jalview/gui/IdCanvas.java b/src/jalview/gui/IdCanvas.java
index 959c83c..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;
     }
 
@@ -109,18 +116,18 @@ public class IdCanvas extends JPanel
 
   void drawIds(int starty, int endy)
   {
-
     Color currentColor     = Color.white;
     Color currentTextColor = Color.black;
 
     if (av.getWrapAlignment())
     {
+
+          int rowSize =  av.getEndRes() - av.getStartRes();
           // Draw the rest of the panels
-          int chunkHeight =  (av.alignment.getHeight() + 2)*av.charHeight;
-          int row = av.getStartRes() / av.chunkWidth ;
-          for(int ypos=2*av.charHeight;
-              ypos <= getHeight() && row*av.chunkWidth<av.alignment.getWidth();
-              ypos += chunkHeight, row++ )
+
+          for(int ypos=2*av.charHeight, row=av.getEndRes()-rowSize;
+              ypos <= getHeight() && row<av.alignment.getWidth();
+              ypos += av.chunkHeight, row+=rowSize )
           {
             for (int i = starty; i < av.alignment.getHeight(); i++)
             {