### Eclipse Workspace Patch 1.0
#P org.eclipse.gef
Index: src/org/eclipse/gef/tools/ResizeTracker.java
===================================================================
RCS file: /cvsroot/tools/org.eclipse.gef/plugins/org.eclipse.gef/src/org/eclipse/gef/tools/ResizeTracker.java,v
retrieving revision 1.38
diff -u -r1.38 ResizeTracker.java
--- src/org/eclipse/gef/tools/ResizeTracker.java	7 Jun 2005 19:57:36 -0000	1.38
+++ src/org/eclipse/gef/tools/ResizeTracker.java	30 Apr 2008 21:20:42 -0000
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2000, 2005 IBM Corporation and others.
+ * Copyright (c) 2000, 2008 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -10,10 +10,12 @@
  *******************************************************************************/
 package org.eclipse.gef.tools;
 
+import java.util.Collections;
 import java.util.List;
 
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.graphics.Cursor;
+import org.eclipse.swt.widgets.Display;
 
 import org.eclipse.draw2d.IFigure;
 import org.eclipse.draw2d.PositionConstants;
@@ -23,6 +25,7 @@
 import org.eclipse.draw2d.geometry.PrecisionPoint;
 import org.eclipse.draw2d.geometry.PrecisionRectangle;
 
+import org.eclipse.gef.AutoexposeHelper;
 import org.eclipse.gef.EditPart;
 import org.eclipse.gef.GraphicalEditPart;
 import org.eclipse.gef.Request;
@@ -55,7 +58,96 @@
 private GraphicalEditPart owner;
 private PrecisionRectangle sourceRect;
 private SnapToHelper snapToHelper;
+private PrecisionPoint sourceRelativeStartPoint;
 
+private AutoexposeHelper exposeHelper;
+
+class QueuedAutoexpose implements Runnable {
+    public void run() {
+        if (exposeHelper != null)
+            doAutoexpose();
+    }
+}
+/**
+ * Called to perform an iteration of the autoexpose process.  If the expose helper is set,
+ * it will be asked to step at the current mouse location.  If it returns true, another
+ * expose iteration will be queued.  There is no delay between autoexpose events, other
+ * than the time required to perform the step().
+ */
+protected void doAutoexpose() {
+    if (exposeHelper == null)
+        return;
+    if (exposeHelper.step(getLocation())) {
+        handleAutoexpose();
+        Display.getCurrent().asyncExec(new QueuedAutoexpose());
+    } else
+        setAutoexposeHelper(null);
+}
+protected void handleAutoexpose() {
+    updateSourceRequest();
+    showSourceFeedback();
+    showTargetFeedback();
+    setCurrentCommand(getCommand());
+}
+/**
+ * Returns <code>null</code> or the current autoexpose helper.
+ * @return null or a helper
+ */
+protected AutoexposeHelper getAutoexposeHelper() {
+    return exposeHelper;
+}
+/**
+ * Sets the active autoexpose helper to the given helper, or <code>null</code>.  If the
+ * helper is not <code>null</code>, a runnable is queued on the event thread that will
+ * trigger a subsequent {@link #doAutoexpose()}.  The helper is typically updated only on
+ * a hover event.
+ * @param helper the new autoexpose helper or <code>null</code>
+ */
+protected void setAutoexposeHelper(AutoexposeHelper helper) {
+    exposeHelper = helper;
+    if (exposeHelper == null)
+        return;
+    Display.getCurrent().asyncExec(new QueuedAutoexpose());
+    
+    if (sourceRelativeStartPoint == null && isInDragInProgress()) {
+        IFigure figure = getTargetEditPart().getFigure();
+        sourceRelativeStartPoint = new PrecisionPoint(getStartLocation());
+        figure.translateToRelative(sourceRelativeStartPoint);
+    }
+}
+/**
+ * Updates the active {@link AutoexposeHelper}. Does nothing if there is still an active
+ * helper. Otherwise, obtains a new helper (possible <code>null</code>) at the current
+ * mouse location and calls {@link #setAutoexposeHelper(AutoexposeHelper)}.
+ */
+protected void updateAutoexposeHelper() {
+    if (exposeHelper != null)
+        return;
+    AutoexposeHelper.Search search;
+    search = new AutoexposeHelper.Search(getLocation());
+    getCurrentViewer()
+        .findObjectAtExcluding(getLocation(), Collections.EMPTY_LIST, search);
+    setAutoexposeHelper(search.result);
+}
+
+/**
+ * If auto scroll (also called auto expose) is being performed, the start location moves 
+ * during the scroll. This method updates that location.
+ */
+protected void repairStartLocation() {
+    if (sourceRelativeStartPoint == null)
+        return;
+    IFigure figure = getTargetEditPart().getFigure();
+    PrecisionPoint newStart = (PrecisionPoint)sourceRelativeStartPoint.getCopy();
+    figure.translateToAbsolute(newStart);
+    Point delta = new Point(newStart.x - getStartLocation().x,
+                            newStart.y - getStartLocation().y);
+    setStartLocation(newStart);
+    // sourceRect needs to be updated as well when auto-scrolling
+    if (sourceRect != null)
+        sourceRect.translate(delta);
+;
+}
 /**
  * Constructs a resize tracker that resizes in the specified direction.  The direction is
  * specified using {@link PositionConstants#NORTH}, {@link PositionConstants#NORTH_EAST},
@@ -133,6 +225,8 @@
 	// For the case where ESC key was hit while resizing
 	eraseTargetFeedback();
 	
+	sourceRelativeStartPoint = null;
+	setAutoexposeHelper(null);
 	sourceRect = null;
 	snapToHelper = null;
 	super.deactivate();
@@ -234,8 +328,14 @@
 		showTargetFeedback();
 		setCurrentCommand(getCommand());
 	}
+        
 	return true;
 }
+protected boolean handleHover() {
+    if (isInDragInProgress())
+        updateAutoexposeHelper();
+    return true;
+}
 
 /**
  * This method is invoked as the drag is happening.  It notifies the 
@@ -251,6 +351,8 @@
  * @see org.eclipse.gef.tools.SimpleDragTracker#updateSourceRequest()
  */
 protected void updateSourceRequest() {
+    repairStartLocation();
+
 	ChangeBoundsRequest request = (ChangeBoundsRequest) getSourceRequest();
 	Dimension d = getDragMoveDelta();