Index: pitivi/ui/tracklayer.py
===================================================================
--- pitivi/ui/tracklayer.py	(revision 1108)
+++ pitivi/ui/tracklayer.py	(working copy)
@@ -55,7 +55,19 @@
     border = 5
     effectgutter = 5
     layergutter = 5
+    handlesize = 10    # how big an offest in pixels should be reserved
+                       # for punch in and punch out handles 
+                       # TODO: get this value somehow from the gtk+ theme 
 
+    # _modifyState states
+    # it should be noted that extending the punch out time beyond the clip
+    # should repeat the clip from the start (used for looped animations or
+    # stills) 
+    (MODIFY_NONE,                   # no modification happening
+     MODIFY_MOVE,                   # moving source in timeline
+     MODIFY_IN,                     # modifying the punch in time for the clip 
+     MODIFY_OUT) = range(4)         # modifying the punch out time for the clip
+
     def __init__(self, layerInfo, hadj):
         gst.log("new TrackLayer for composition %r" % layerInfo.composition)
         gtk.Layout.__init__(self)
@@ -84,10 +96,12 @@
         self.connect('button-release-event', self._buttonReleaseEventCb)
 
         self._mouseDownPosition = [None, None]
-        self._movingSource = None
+        self._modifyingSource = None
         self._origSourcePosition = None
         self._requestedPosition = None
-        self._currentlyMoving = False
+        self._requestedDuration = None
+        self._currentlyModifying = False
+        self._modificationState = self.MODIFY_NONE
 
         self._popupMenu = gtk.Menu()
         deleteitem = gtk.MenuItem(_("Remove"))
@@ -108,8 +122,8 @@
     def _deleteMenuItemCb(self, unused_menuitem):
         # remove currently selected source
         gst.log("removing source")
-        self.layerInfo.composition.removeSource(self._movingSource)
-        self._movingSource = None
+        self.layerInfo.composition.removeSource(self._modifyingSource)
+        self._modifyingSource = None
 
     def _cutMenuItemCb(self, unused_menuitem):
         gst.log("cut at position %s" % gst.TIME_ARGS(self.position))
@@ -240,10 +254,11 @@
                                       x, y, x, y, width, height)
         return gtk.Layout.do_expose_event(self, event)
 
-    def _moveTimeoutCb(self):
-        self._currentlyMoving = False
-        if self._requestedPosition and self._movingSource:
-            self._movingSource.setStartDurationTime(start = self._requestedPosition)
+    def _modifyTimeoutCb(self):
+        self._currentlyModifying = False
+        if self._requestedPosition and self._modifyingSource:
+            self._modifyingSource.setStartDurationTime(start = self._requestedPosition,
+                                                       duration = self._requestedDuration)
 
     def do_motion_notify_event(self, event):
         gst.debug("motion x:%d y:%d" % (event.x , event.y))
@@ -251,17 +266,38 @@
             diffx = event.x - self._mouseDownPosition[0]
             diffy = event.y - self._mouseDownPosition[1]
             gst.debug("we moved by x:%d, y:%d" % (diffx, diffy))
-            if self._movingSource:
-                newstart = self._origSourcePosition + self.pixelToNs(diffx)
+
+            if self._modifyingSource:
+                newstart = self._origSourcePosition
+                print self._modificationState
+                if (self._modificationState == self.MODIFY_MOVE or
+                  self._modificationState == self.MODIFY_IN):
+                    newstart += self.pixelToNs(diffx)
+                
+                newduration = self._origSourceDuration
+                if self._modificationState == self.MODIFY_IN:
+                    newduration -= self.pixelToNs(diffx)
+                elif self._modificationState == self.MODIFY_OUT:
+                    newduration += self.pixelToNs(diffx)
+
                 # FIXME : implement blocking !!
                 if newstart < 0:
                     newstart = 0
+
+                if newduration < 1:
+                    newduration = 1
+
                 gst.debug("we should move the source to %s" % gst.TIME_ARGS(newstart))
-                if not self._currentlyMoving:
-                    self._currentlyMoving = True
-                    gobject.timeout_add(80, self._moveTimeoutCb)
-                    self._movingSource.setStartDurationTime(start = newstart)
+
+
+                if not self._currentlyModifying:
+                    self._currentlyModifying = True
+                    gobject.timeout_add(80, self._modifyTimeoutCb)
+                    print newstart, newduration
+                    self._modifyingSource.setStartDurationTime(start = newstart, 
+                                                               duration = newduration)
                 self._requestedPosition = newstart
+                self._requestedDuration = newduration
 
     ## Drawing methods
 
@@ -360,23 +396,37 @@
             gst.log("Mouse down at %d / %d" % (event.x, event.y))
             source = self._findSourceAtPosition(event.x)
             if source:
-                gst.log("we are moving %s" % source)
-                self._movingSource = source
+                gst.log("we are modifying %s" % source)
+                widget = self.sources[source]
+                minv = widget.getPixelPosition()
+                maxv = minv + widget.getPixelWidth()
+                if event.x < minv + self.handlesize:
+                    self._modificationState = self.MODIFY_IN
+                elif event.x > maxv - self.handlesize:
+                    self._modificationState = self.MODIFY_OUT
+                else:
+                    self._modificationState = self.MODIFY_MOVE
+
+                self._modifyingSource = source
                 self._origSourcePosition = source.start
+                self._origSourceDuration = source.duration
         elif event.button == 3:
             source = self._findSourceAtPosition(event.x)
             if source:
-                gst.log("we are moving %s" % source)
-                self._movingSource = source
+                gst.log("we are modifying %s" % source)
+                self._modifyingSource = source
                 self._origSourcePosition = source.start
+                self._origSourceDuration = source.duration
                 self._popupMenu.popup(None,None,None, event.button, event.time)
 
     def _buttonReleaseEventCb(self, unused_layout, unused_event):
         gst.log("Mouse up !")
         # reset values
         self._mouseDownPosition = [None,None]
-        self._movingSource = None
+        self._modifyingSource = None
         self._origSourcePosition = None
+        self._origSourceDuration = None
+        self._modificationState = self.MODIFY_NONE
 
     def _findSourceAtPosition(self, position):
         """