X-Git-Url: http://source.jalview.org/gitweb/?a=blobdiff_plain;f=src%2Fjalview%2Fviewmodel%2FViewportRanges.java;h=24ff57f46861e3ffed3004250946f89b97892260;hb=0ebfeaf22a68a4c2760ef6980d68ede56ad40eb3;hp=10cf583d032a71f4aff9f29c44c44d56d3e8136d;hpb=e54df488cd82761bfb0e9372aeae2acc5a1324d7;p=jalview.git

diff --git a/src/jalview/viewmodel/ViewportRanges.java b/src/jalview/viewmodel/ViewportRanges.java
index 10cf583..24ff57f 100644
--- a/src/jalview/viewmodel/ViewportRanges.java
+++ b/src/jalview/viewmodel/ViewportRanges.java
@@ -402,23 +402,39 @@ public class ViewportRanges extends ViewportProperties
    */
   public boolean scrollUp(boolean up)
   {
+    /*
+     * if in unwrapped mode, scroll up or down one sequence row;
+     * if in wrapped mode, scroll by one visible width of columns
+     */
     if (up)
     {
-      if (startSeq < 1)
+      if (wrappedMode)
       {
-        return false;
+        pageUp();
+      }
+      else
+      {
+        if (startSeq < 1)
+        {
+          return false;
+        }
+        setStartSeq(startSeq - 1);
       }
-
-      setStartSeq(startSeq - 1);
     }
     else
     {
-      if (endSeq >= getVisibleAlignmentHeight() - 1)
+      if (wrappedMode)
       {
-        return false;
+        pageDown();
+      }
+      else
+      {
+        if (endSeq >= getVisibleAlignmentHeight() - 1)
+        {
+          return false;
+        }
+        setStartSeq(startSeq + 1);
       }
-
-      setStartSeq(startSeq + 1);
     }
     return true;
   }
@@ -456,18 +472,42 @@ public class ViewportRanges extends ViewportProperties
   }
 
   /**
-   * Scroll a wrapped alignment so that the specified residue is visible. Fires
-   * a property change event.
+   * Scroll a wrapped alignment so that the specified residue is in the first
+   * repeat of the wrapped view. Fires a property change event. Answers true if
+   * the startRes changed, else false.
    * 
    * @param res
    *          residue position to scroll to
+   * @return
    */
-  public void scrollToWrappedVisible(int res)
+  public boolean scrollToWrappedVisible(int res)
   {
-    // get the start residue of the wrapped row which res is in
-    // and set that as our start residue
+    int oldStartRes = startRes;
     int width = getViewportWidth();
-    setStartRes((res / width) * width);
+
+    if (res >= oldStartRes && res < oldStartRes + width)
+    {
+      return false;
+    }
+
+    boolean up = res < oldStartRes;
+    int widthsToScroll = Math.abs((res - oldStartRes) / width);
+    if (up)
+    {
+      widthsToScroll++;
+    }
+
+    int residuesToScroll = width * widthsToScroll;
+    int newStartRes = up ? oldStartRes - residuesToScroll : oldStartRes
+            + residuesToScroll;
+    if (newStartRes < 0)
+    {
+      newStartRes = 0;
+    }
+
+    setStartRes(newStartRes);
+
+    return true;
   }
 
   /**
@@ -505,7 +545,7 @@ public class ViewportRanges extends ViewportProperties
       }
     }
   }
-  
+
   /**
    * Adjust sequence position for page up. Fires a property change event.
    */
@@ -521,7 +561,7 @@ public class ViewportRanges extends ViewportProperties
               getViewportHeight());
     }
   }
-  
+
   /**
    * Adjust sequence position for page down. Fires a property change event.
    */