code: def rebuild( self ):
          
          scene      = self.scene()
          if ( not scene ):
              return
          
          sourcePos  = self.sourceItem().viewItem().pos()
          sourceRect = self.sourceItem().viewItem().rect()
          
          targetPos  = self.targetItem().viewItem().pos()
          targetRect = self.targetItem().viewItem().rect()
          
          cellWidth  = scene.ganttWidget().cellWidth()
          
          startX = sourcePos.x() + sourceRect.width() - (cellWidth / 2.0)
          startY = sourcePos.y() + (sourceRect.height() / 2.0)
          
          endX   = targetPos.x() - 2
          endY   = targetPos.y() + (targetRect.height() / 2.0)
          
          path = QPainterPath()
          path.moveTo(startX, startY)
          path.lineTo(startX, endY)
          path.lineTo(endX, endY)
          
          a = QPointF(endX - 10, endY - 3)
          b = QPointF(endX, endY)
          c = QPointF(endX - 10, endY + 3)
          
          self._polygon = QPolygonF([a, b, c, a])
          
          path.addPolygon(self._polygon)
          
          self.setPath(path)
docs: Rebuilds the dependency path for this item.