controls/DebugVariablePanel/DebugVariableGraphicPanel.py
changeset 1198 8b4e6bd0aa92
parent 1194 0cf48602ee24
child 1199 fc0e7d80494f
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/controls/DebugVariablePanel/DebugVariableGraphicPanel.py	Thu May 30 11:52:42 2013 +0200
@@ -0,0 +1,1842 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+#This file is part of PLCOpenEditor, a library implementing an IEC 61131-3 editor
+#based on the plcopen standard. 
+#
+#Copyright (C) 2012: Edouard TISSERANT and Laurent BESSARD
+#
+#See COPYING file for copyrights details.
+#
+#This library is free software; you can redistribute it and/or
+#modify it under the terms of the GNU General Public
+#License as published by the Free Software Foundation; either
+#version 2.1 of the License, or (at your option) any later version.
+#
+#This library is distributed in the hope that it will be useful,
+#but WITHOUT ANY WARRANTY; without even the implied warranty of
+#MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+#General Public License for more details.
+#
+#You should have received a copy of the GNU General Public
+#License along with this library; if not, write to the Free Software
+#Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+from types import TupleType
+from time import time as gettime
+import math
+import numpy
+
+import wx
+import wx.lib.buttons
+
+import matplotlib
+matplotlib.use('WX')
+import matplotlib.pyplot
+from matplotlib.backends.backend_wxagg import FigureCanvasWxAgg as FigureCanvas
+from matplotlib.backends.backend_wxagg import _convert_agg_to_wx_bitmap
+from matplotlib.backends.backend_agg import FigureCanvasAgg
+from mpl_toolkits.mplot3d import Axes3D
+color_cycle = ['r', 'b', 'g', 'm', 'y', 'k']
+cursor_color = '#800080'
+
+from editors.DebugViewer import DebugViewer, REFRESH_PERIOD
+from controls.DebugVariablePanel.DebugVariableItem import DebugVariableItem
+from dialogs.ForceVariableDialog import ForceVariableDialog
+from util.BitmapLibrary import GetBitmap
+
+class DebugVariableDropTarget(wx.TextDropTarget):
+    
+    def __init__(self, parent, control=None):
+        wx.TextDropTarget.__init__(self)
+        self.ParentWindow = parent
+        self.ParentControl = control
+    
+    def __del__(self):
+        self.ParentWindow = None
+        self.ParentControl = None
+    
+    def OnDragOver(self, x, y, d):
+        if self.ParentControl is not None:
+            self.ParentControl.OnMouseDragging(x, y)
+        else:
+            self.ParentWindow.RefreshHighlight(x, y)
+        return wx.TextDropTarget.OnDragOver(self, x, y, d)
+        
+    def OnDropText(self, x, y, data):
+        message = None
+        try:
+            values = eval(data)
+        except:
+            message = _("Invalid value \"%s\" for debug variable")%data
+            values = None
+        if not isinstance(values, TupleType):
+            message = _("Invalid value \"%s\" for debug variable")%data
+            values = None
+        
+        if message is not None:
+            wx.CallAfter(self.ShowMessage, message)
+        elif values is not None and values[1] == "debug":
+            if self.ParentControl is not None:
+                width, height = self.ParentControl.GetSize()
+                target_idx = self.ParentControl.GetIndex()
+                merge_type = GRAPH_PARALLEL
+                if isinstance(self.ParentControl, DebugVariableGraphic):
+                    if self.ParentControl.Is3DCanvas():
+                        if y > height / 2:
+                            target_idx += 1
+                        if len(values) > 1 and values[2] == "move":
+                            self.ParentWindow.MoveValue(values[0], target_idx)
+                        else:
+                            self.ParentWindow.InsertValue(values[0], target_idx, force=True)
+                        
+                    else:
+                        rect = self.ParentControl.GetAxesBoundingBox()
+                        if rect.InsideXY(x, y):
+                            merge_rect = wx.Rect(rect.x, rect.y, rect.width / 2., rect.height)
+                            if merge_rect.InsideXY(x, y):
+                                merge_type = GRAPH_ORTHOGONAL
+                            wx.CallAfter(self.ParentWindow.MergeGraphs, values[0], target_idx, merge_type, force=True)
+                        else:
+                            if y > height / 2:
+                                target_idx += 1
+                            if len(values) > 2 and values[2] == "move":
+                                self.ParentWindow.MoveValue(values[0], target_idx)
+                            else:
+                                self.ParentWindow.InsertValue(values[0], target_idx, force=True)
+                else:
+                    if y > height / 2:
+                        target_idx += 1
+                    if len(values) > 2 and values[2] == "move":
+                        self.ParentWindow.MoveValue(values[0], target_idx)
+                    else:
+                        self.ParentWindow.InsertValue(values[0], target_idx, force=True)
+                    
+            elif len(values) > 2 and values[2] == "move":
+                self.ParentWindow.MoveValue(values[0])
+            else:
+                self.ParentWindow.InsertValue(values[0], force=True)
+    
+    def OnLeave(self):
+        self.ParentWindow.ResetHighlight()
+        return wx.TextDropTarget.OnLeave(self)
+    
+    def ShowMessage(self, message):
+        dialog = wx.MessageDialog(self.ParentWindow, message, _("Error"), wx.OK|wx.ICON_ERROR)
+        dialog.ShowModal()
+        dialog.Destroy()
+
+MILLISECOND = 1000000
+SECOND = 1000 * MILLISECOND
+MINUTE = 60 * SECOND
+HOUR = 60 * MINUTE
+DAY = 24 * HOUR
+
+ZOOM_VALUES = map(lambda x:("x %.1f" % x, x), [math.sqrt(2) ** i for i in xrange(8)])
+RANGE_VALUES = \
+    [("%dms" % i, i * MILLISECOND) for i in (10, 20, 50, 100, 200, 500)] + \
+    [("%ds" % i, i * SECOND) for i in (1, 2, 5, 10, 20, 30)] + \
+    [("%dm" % i, i * MINUTE) for i in (1, 2, 5, 10, 20, 30)] + \
+    [("%dh" % i, i * HOUR) for i in (1, 2, 3, 6, 12, 24)]
+
+GRAPH_PARALLEL, GRAPH_ORTHOGONAL = range(2)
+
+SCROLLBAR_UNIT = 10
+
+#CANVAS_HIGHLIGHT_TYPES
+[HIGHLIGHT_NONE,
+ HIGHLIGHT_BEFORE,
+ HIGHLIGHT_AFTER,
+ HIGHLIGHT_LEFT,
+ HIGHLIGHT_RIGHT,
+ HIGHLIGHT_RESIZE] = range(6)
+
+HIGHLIGHT_DROP_PEN = wx.Pen(wx.Colour(0, 128, 255))
+HIGHLIGHT_DROP_BRUSH = wx.Brush(wx.Colour(0, 128, 255, 128))
+HIGHLIGHT_RESIZE_PEN = wx.Pen(wx.Colour(200, 200, 200))
+HIGHLIGHT_RESIZE_BRUSH = wx.Brush(wx.Colour(200, 200, 200))
+
+#CANVAS_SIZE_TYPES
+[SIZE_MINI, SIZE_MIDDLE, SIZE_MAXI] = [0, 100, 200]
+
+DEFAULT_CANVAS_HEIGHT = 200.
+CANVAS_BORDER = (20., 10.)
+CANVAS_PADDING = 8.5
+VALUE_LABEL_HEIGHT = 17.
+AXES_LABEL_HEIGHT = 12.75
+
+def compute_mask(x, y):
+    mask = []
+    for xp, yp in zip(x, y):
+        if xp == yp:
+            mask.append(xp)
+        else:
+            mask.append("*")
+    return mask
+
+def NextTick(variables):
+    next_tick = None
+    for item, data in variables:
+        if len(data) > 0:
+            if next_tick is None:
+                next_tick = data[0][0]
+            else:
+                next_tick = min(next_tick, data[0][0])
+    return next_tick
+
+def OrthogonalData(item, start_tick, end_tick):
+    data = item.GetData(start_tick, end_tick)
+    min_value, max_value = item.GetValueRange()
+    if min_value is not None and max_value is not None:
+        center = (min_value + max_value) / 2.
+        range = max(1.0, max_value - min_value)
+    else:
+        center = 0.5
+        range = 1.0
+    return data, center - range * 0.55, center + range * 0.55
+
+class GraphButton():
+    
+    def __init__(self, x, y, bitmap, callback):
+        self.Position = wx.Point(x, y)
+        self.Bitmap = bitmap
+        self.Shown = True
+        self.Enabled = True
+        self.Callback = callback
+    
+    def __del__(self):
+        self.callback = None
+    
+    def GetSize(self):
+        return self.Bitmap.GetSize()
+    
+    def SetPosition(self, x, y):
+        self.Position = wx.Point(x, y)
+    
+    def Show(self):
+        self.Shown = True
+        
+    def Hide(self):
+        self.Shown = False
+    
+    def IsShown(self):
+        return self.Shown
+    
+    def Enable(self):
+        self.Enabled = True
+    
+    def Disable(self):
+        self.Enabled = False
+    
+    def IsEnabled(self):
+        return self.Enabled
+    
+    def HitTest(self, x, y):
+        if self.Shown and self.Enabled:
+            w, h = self.Bitmap.GetSize()
+            rect = wx.Rect(self.Position.x, self.Position.y, w, h)
+            if rect.InsideXY(x, y):
+                return True
+        return False
+    
+    def ProcessCallback(self):
+        if self.Callback is not None:
+            wx.CallAfter(self.Callback)
+            
+    def Draw(self, dc):
+        if self.Shown and self.Enabled:
+            dc.DrawBitmap(self.Bitmap, self.Position.x, self.Position.y, True)
+
+class DebugVariableViewer:
+    
+    def __init__(self, window, items=[]):
+        self.ParentWindow = window
+        self.Items = items
+        
+        self.Highlight = HIGHLIGHT_NONE
+        self.Buttons = []
+    
+    def __del__(self):
+        self.ParentWindow = None
+    
+    def GetIndex(self):
+        return self.ParentWindow.GetViewerIndex(self)
+    
+    def GetItem(self, variable):
+        for item in self.Items:
+            if item.GetVariable() == variable:
+                return item
+        return None
+    
+    def GetItems(self):
+        return self.Items
+    
+    def GetVariables(self):
+        if len(self.Items) > 1:
+            variables = [item.GetVariable() for item in self.Items]
+            if self.GraphType == GRAPH_ORTHOGONAL:
+                return tuple(variables)
+            return variables
+        return self.Items[0].GetVariable()
+    
+    def AddItem(self, item):
+        self.Items.append(item)
+        
+    def RemoveItem(self, item):
+        if item in self.Items:
+            self.Items.remove(item)
+        
+    def Clear(self):
+        for item in self.Items:
+            self.ParentWindow.RemoveDataConsumer(item)
+        self.Items = []
+        
+    def IsEmpty(self):
+        return len(self.Items) == 0
+    
+    def UnregisterObsoleteData(self):
+        for item in self.Items[:]:
+            iec_path = item.GetVariable()
+            if self.ParentWindow.GetDataType(iec_path) is None:
+                self.ParentWindow.RemoveDataConsumer(item)
+                self.RemoveItem(item)
+            else:
+                self.ParentWindow.AddDataConsumer(iec_path.upper(), item)
+                item.RefreshVariableType()
+        
+    def ResetData(self):
+        for item in self.Items:
+            item.ResetData()
+    
+    def RefreshViewer(self):
+        pass
+    
+    def SetHighlight(self, highlight):
+        if self.Highlight != highlight:
+            self.Highlight = highlight
+            return True
+        return False
+    
+    def GetButtons(self):
+        return self.Buttons
+    
+    def HandleButtons(self, x, y):
+        for button in self.GetButtons():
+            if button.HitTest(x, y):
+                button.ProcessCallback()
+                return True
+        return False
+    
+    def IsOverButton(self, x, y):
+        for button in self.GetButtons():
+            if button.HitTest(x, y):
+                return True
+        return False
+    
+    def ShowButtons(self, show):
+        for button in self.Buttons:
+            if show:
+                button.Show()
+            else:
+                button.Hide()
+        self.RefreshButtonsState()
+        self.ParentWindow.ForceRefresh()
+    
+    def RefreshButtonsState(self, refresh_positions=False):
+        if self:
+            width, height = self.GetSize()
+            if refresh_positions:
+                offset = 0
+                buttons = self.Buttons[:]
+                buttons.reverse()
+                for button in buttons:
+                    w, h = button.GetSize()
+                    button.SetPosition(width - 5 - w - offset, 5)
+                    offset += w + 2
+                self.ParentWindow.ForceRefresh()
+    
+    def DrawCommonElements(self, dc, buttons=None):
+        width, height = self.GetSize()
+        
+        dc.SetPen(HIGHLIGHT_DROP_PEN)
+        dc.SetBrush(HIGHLIGHT_DROP_BRUSH)
+        if self.Highlight in [HIGHLIGHT_BEFORE]:
+            dc.DrawLine(0, 1, width - 1, 1)
+        elif self.Highlight in [HIGHLIGHT_AFTER]:
+            dc.DrawLine(0, height - 1, width - 1, height - 1)
+        
+        if buttons is None:
+            buttons = self.Buttons
+        for button in buttons:
+            button.Draw(dc)
+            
+        if self.ParentWindow.IsDragging():
+            destBBox = self.ParentWindow.GetDraggingAxesClippingRegion(self)
+            srcPos = self.ParentWindow.GetDraggingAxesPosition(self)
+            if destBBox.width > 0 and destBBox.height > 0:
+                srcPanel = self.ParentWindow.DraggingAxesPanel
+                srcBBox = srcPanel.GetAxesBoundingBox()
+                
+                if destBBox.x == 0:
+                    srcX = srcBBox.x - srcPos.x
+                else:
+                    srcX = srcBBox.x
+                if destBBox.y == 0:
+                    srcY = srcBBox.y - srcPos.y
+                else:
+                    srcY = srcBBox.y
+                
+                srcBmp = _convert_agg_to_wx_bitmap(srcPanel.get_renderer(), None)
+                srcDC = wx.MemoryDC()
+                srcDC.SelectObject(srcBmp)
+                
+                dc.Blit(destBBox.x, destBBox.y, 
+                        int(destBBox.width), int(destBBox.height), 
+                        srcDC, srcX, srcY)
+    
+    def OnEnter(self, event):
+        self.ShowButtons(True)
+        event.Skip()
+        
+    def OnLeave(self, event):
+        if self.Highlight != HIGHLIGHT_RESIZE or self.CanvasStartSize is None:
+            x, y = event.GetPosition()
+            width, height = self.GetSize()
+            if (x <= 0 or x >= width - 1 or
+                y <= 0 or y >= height - 1):
+                self.ShowButtons(False)
+        event.Skip()
+    
+    def OnCloseButton(self):
+        wx.CallAfter(self.ParentWindow.DeleteValue, self)
+    
+    def OnForceButton(self):
+        wx.CallAfter(self.ForceValue, self.Items[0])
+        
+    def OnReleaseButton(self):
+        wx.CallAfter(self.ReleaseValue, self.Items[0])
+    
+    def OnResizeWindow(self, event):
+        wx.CallAfter(self.RefreshButtonsState, True)
+        event.Skip()
+    
+    def OnMouseDragging(self, x, y):
+        xw, yw = self.GetPosition()
+        self.ParentWindow.RefreshHighlight(x + xw, y + yw)
+    
+    def OnDragging(self, x, y):
+        width, height = self.GetSize()
+        if y < height / 2:
+            if self.ParentWindow.IsViewerFirst(self):
+                self.SetHighlight(HIGHLIGHT_BEFORE)
+            else:
+                self.SetHighlight(HIGHLIGHT_NONE)
+                self.ParentWindow.HighlightPreviousViewer(self)
+        else:
+            self.SetHighlight(HIGHLIGHT_AFTER)
+    
+    def OnEraseBackground(self, event):
+        pass
+    
+    def OnResize(self, event):
+        wx.CallAfter(self.RefreshButtonsState, True)
+        event.Skip()
+    
+    def ForceValue(self, item):
+        iec_path = item.GetVariable()
+        iec_type = self.ParentWindow.GetDataType(iec_path)
+        if iec_type is not None:
+            dialog = ForceVariableDialog(self, iec_type, str(item.GetValue()))
+            if dialog.ShowModal() == wx.ID_OK:
+                self.ParentWindow.ForceDataValue(iec_path.upper(), dialog.GetValue())
+    
+    def ReleaseValue(self, item):
+        iec_path = item.GetVariable().upper()
+        self.ParentWindow.ReleaseDataValue(iec_path)
+
+
+class DebugVariableText(DebugVariableViewer, wx.Panel):
+    
+    def __init__(self, parent, window, items=[]):
+        DebugVariableViewer.__init__(self, window, items)
+        
+        wx.Panel.__init__(self, parent)
+        self.SetBackgroundColour(wx.WHITE)
+        self.SetDropTarget(DebugVariableDropTarget(window, self))
+        self.Bind(wx.EVT_LEFT_DOWN, self.OnLeftDown)
+        self.Bind(wx.EVT_LEFT_UP, self.OnLeftUp)
+        self.Bind(wx.EVT_ENTER_WINDOW, self.OnEnter)
+        self.Bind(wx.EVT_LEAVE_WINDOW, self.OnLeave)
+        self.Bind(wx.EVT_SIZE, self.OnResize)
+        self.Bind(wx.EVT_ERASE_BACKGROUND, self.OnEraseBackground)
+        self.Bind(wx.EVT_PAINT, self.OnPaint)
+        
+        self.SetMinSize(wx.Size(0, 25))
+        
+        self.Buttons.append(
+            GraphButton(0, 0, GetBitmap("force"), self.OnForceButton))
+        self.Buttons.append(
+            GraphButton(0, 0, GetBitmap("release"), self.OnReleaseButton))
+        self.Buttons.append(
+            GraphButton(0, 0, GetBitmap("delete_graph"), self.OnCloseButton))
+        
+        self.ShowButtons(False)
+        
+    def RefreshViewer(self):
+        width, height = self.GetSize()
+        bitmap = wx.EmptyBitmap(width, height)
+        
+        dc = wx.BufferedDC(wx.ClientDC(self), bitmap)
+        dc.Clear()
+        dc.BeginDrawing()
+        
+        gc = wx.GCDC(dc)
+        
+        item_name = self.Items[0].GetVariable(self.ParentWindow.GetVariableNameMask())
+        w, h = gc.GetTextExtent(item_name)
+        gc.DrawText(item_name, 20, (height - h) / 2)
+        
+        if self.Items[0].IsForced():
+            gc.SetTextForeground(wx.BLUE)
+            self.Buttons[0].Disable()
+            self.Buttons[1].Enable()
+        else:
+            self.Buttons[1].Disable()
+            self.Buttons[0].Enable()
+        self.RefreshButtonsState(True)
+        
+        item_value = self.Items[0].GetValue()
+        w, h = gc.GetTextExtent(item_value)
+        gc.DrawText(item_value, width - 40 - w, (height - h) / 2)
+        
+        self.DrawCommonElements(gc)
+        
+        gc.EndDrawing()
+    
+    def OnLeftDown(self, event):
+        width, height = self.GetSize()
+        item_name = self.Items[0].GetVariable(self.ParentWindow.GetVariableNameMask())
+        w, h = self.GetTextExtent(item_name)
+        x, y = event.GetPosition()
+        rect = wx.Rect(20, (height - h) / 2, w, h)
+        if rect.InsideXY(x, y):
+            data = wx.TextDataObject(str((self.Items[0].GetVariable(), "debug", "move")))
+            dragSource = wx.DropSource(self)
+            dragSource.SetData(data)
+            dragSource.DoDragDrop()
+        else:
+            event.Skip()
+    
+    def OnLeftUp(self, event):
+        x, y = event.GetPosition()
+        wx.CallAfter(self.HandleButtons, x, y)
+        event.Skip()
+    
+    def OnPaint(self, event):
+        self.RefreshViewer()
+        event.Skip()
+
+class DebugVariableGraphic(DebugVariableViewer, FigureCanvas):
+    
+    def __init__(self, parent, window, items, graph_type):
+        DebugVariableViewer.__init__(self, window, items)
+        
+        self.CanvasSize = SIZE_MINI
+        self.GraphType = graph_type
+        self.CursorTick = None
+        self.MouseStartPos = None
+        self.StartCursorTick = None
+        self.CanvasStartSize = None
+        self.ContextualButtons = []
+        self.ContextualButtonsItem = None
+        
+        self.Figure = matplotlib.figure.Figure(facecolor='w')
+        self.Figure.subplotpars.update(top=0.95, left=0.1, bottom=0.1, right=0.95)
+        
+        FigureCanvas.__init__(self, parent, -1, self.Figure)
+        self.SetWindowStyle(wx.WANTS_CHARS)
+        self.SetBackgroundColour(wx.WHITE)
+        self.Bind(wx.EVT_KEY_DOWN, self.OnKeyDown)
+        self.Bind(wx.EVT_ENTER_WINDOW, self.OnEnter)
+        self.Bind(wx.EVT_LEAVE_WINDOW, self.OnLeave)
+        self.Bind(wx.EVT_ERASE_BACKGROUND, self.OnEraseBackground)
+        self.Bind(wx.EVT_SIZE, self.OnResize)
+        
+        canvas_size = self.GetCanvasMinSize()
+        self.SetMinSize(canvas_size)
+        self.SetDropTarget(DebugVariableDropTarget(self.ParentWindow, self))
+        self.mpl_connect('button_press_event', self.OnCanvasButtonPressed)
+        self.mpl_connect('motion_notify_event', self.OnCanvasMotion)
+        self.mpl_connect('button_release_event', self.OnCanvasButtonReleased)
+        self.mpl_connect('scroll_event', self.OnCanvasScroll)
+        
+        for size, bitmap in zip([SIZE_MINI, SIZE_MIDDLE, SIZE_MAXI],
+                                ["minimize_graph", "middle_graph", "maximize_graph"]):
+            self.Buttons.append(GraphButton(0, 0, GetBitmap(bitmap), self.GetOnChangeSizeButton(size)))
+        self.Buttons.append(
+            GraphButton(0, 0, GetBitmap("export_graph_mini"), self.OnExportGraphButton))
+        self.Buttons.append(
+            GraphButton(0, 0, GetBitmap("delete_graph"), self.OnCloseButton))
+        
+        self.ResetGraphics()
+        self.RefreshLabelsPosition(canvas_size.height)
+        self.ShowButtons(False)
+    
+    def draw(self, drawDC=None):
+        FigureCanvasAgg.draw(self)
+
+        self.bitmap = _convert_agg_to_wx_bitmap(self.get_renderer(), None)
+        self.bitmap.UseAlpha() 
+        width, height = self.GetSize()
+        bbox = self.GetAxesBoundingBox()
+        
+        destDC = wx.MemoryDC()
+        destDC.SelectObject(self.bitmap)
+        
+        destGC = wx.GCDC(destDC)
+        
+        destGC.BeginDrawing()
+        if self.Highlight == HIGHLIGHT_RESIZE:
+            destGC.SetPen(HIGHLIGHT_RESIZE_PEN)
+            destGC.SetBrush(HIGHLIGHT_RESIZE_BRUSH)
+            destGC.DrawRectangle(0, height - 5, width, 5)
+        else:
+            destGC.SetPen(HIGHLIGHT_DROP_PEN)
+            destGC.SetBrush(HIGHLIGHT_DROP_BRUSH)
+            if self.Highlight == HIGHLIGHT_LEFT:
+                destGC.DrawRectangle(bbox.x, bbox.y, 
+                                     bbox.width / 2, bbox.height)
+            elif self.Highlight == HIGHLIGHT_RIGHT:
+                destGC.DrawRectangle(bbox.x + bbox.width / 2, bbox.y, 
+                                     bbox.width / 2, bbox.height)
+        
+        self.DrawCommonElements(destGC, self.Buttons + self.ContextualButtons)
+        
+        destGC.EndDrawing()
+        
+        self._isDrawn = True
+        self.gui_repaint(drawDC=drawDC)
+    
+    def GetButtons(self):
+        return self.Buttons + self.ContextualButtons
+    
+    def PopupContextualButtons(self, item, rect, style=wx.RIGHT):
+        if self.ContextualButtonsItem is not None and item != self.ContextualButtonsItem:
+            self.DismissContextualButtons()
+        
+        if self.ContextualButtonsItem is None:
+            self.ContextualButtonsItem = item
+            
+            if self.ContextualButtonsItem.IsForced():
+                self.ContextualButtons.append(
+                    GraphButton(0, 0, GetBitmap("release"), self.OnReleaseButton))
+            self.ContextualButtons.append(
+                GraphButton(0, 0, GetBitmap("force"), self.OnForceButton))
+            self.ContextualButtons.append(
+                GraphButton(0, 0, GetBitmap("export_graph_mini"), self.OnExportItemGraphButton))
+            self.ContextualButtons.append(
+                GraphButton(0, 0, GetBitmap("delete_graph"), self.OnRemoveItemButton))
+            
+            offset = 0
+            buttons = self.ContextualButtons[:]
+            if style in [wx.TOP, wx.LEFT]:
+                 buttons.reverse()
+            for button in buttons:
+                w, h = button.GetSize()
+                if style in [wx.LEFT, wx.RIGHT]:
+                    if style == wx.LEFT:
+                        x = rect.x - w - offset
+                    else:
+                        x = rect.x + rect.width + offset
+                    y = rect.y + (rect.height - h) / 2
+                    offset += w
+                else:
+                    x = rect.x + (rect.width - w ) / 2
+                    if style == wx.TOP:
+                        y = rect.y - h - offset
+                    else:
+                        y = rect.y + rect.height + offset
+                    offset += h
+                button.SetPosition(x, y)
+            self.ParentWindow.ForceRefresh()
+    
+    def DismissContextualButtons(self):
+        if self.ContextualButtonsItem is not None:
+            self.ContextualButtonsItem = None
+            self.ContextualButtons = []
+            self.ParentWindow.ForceRefresh()
+    
+    def IsOverContextualButton(self, x, y):
+        for button in self.ContextualButtons:
+            if button.HitTest(x, y):
+                return True
+        return False
+    
+    def SetMinSize(self, size):
+        wx.Window.SetMinSize(self, size)
+        wx.CallAfter(self.RefreshButtonsState)
+    
+    def GetOnChangeSizeButton(self, size):
+        def OnChangeSizeButton():
+            self.CanvasSize = size
+            self.SetCanvasSize(200, self.CanvasSize)
+        return OnChangeSizeButton
+    
+    def OnExportGraphButton(self):
+        self.ExportGraph()
+    
+    def OnForceButton(self):
+        wx.CallAfter(self.ForceValue, 
+                     self.ContextualButtonsItem)
+        self.DismissContextualButtons()
+        
+    def OnReleaseButton(self):
+        wx.CallAfter(self.ReleaseValue, 
+                     self.ContextualButtonsItem)
+        self.DismissContextualButtons()
+    
+    def OnExportItemGraphButton(self):
+        wx.CallAfter(self.ExportGraph, 
+                     self.ContextualButtonsItem)
+        self.DismissContextualButtons()
+        
+    def OnRemoveItemButton(self):            
+        wx.CallAfter(self.ParentWindow.DeleteValue, self, 
+                     self.ContextualButtonsItem)
+        self.DismissContextualButtons()
+    
+    def RefreshLabelsPosition(self, height):
+        canvas_ratio = 1. / height
+        graph_ratio = 1. / ((1.0 - (CANVAS_BORDER[0] + CANVAS_BORDER[1]) * canvas_ratio) * height)
+        
+        self.Figure.subplotpars.update(
+            top= 1.0 - CANVAS_BORDER[1] * canvas_ratio, 
+            bottom= CANVAS_BORDER[0] * canvas_ratio)
+        
+        if self.GraphType == GRAPH_PARALLEL or self.Is3DCanvas():
+            num_item = len(self.Items)
+            for idx in xrange(num_item):
+                if not self.Is3DCanvas():
+                    self.AxesLabels[idx].set_position(
+                        (0.05, 
+                         1.0 - (CANVAS_PADDING + AXES_LABEL_HEIGHT * idx) * graph_ratio))
+                self.Labels[idx].set_position(
+                    (0.95, 
+                     CANVAS_PADDING * graph_ratio + 
+                     (num_item - idx - 1) * VALUE_LABEL_HEIGHT * graph_ratio))
+        else:
+            self.AxesLabels[0].set_position((0.1, CANVAS_PADDING * graph_ratio))
+            self.Labels[0].set_position((0.95, CANVAS_PADDING * graph_ratio))
+            self.AxesLabels[1].set_position((0.05, 2 * CANVAS_PADDING * graph_ratio))
+            self.Labels[1].set_position((0.05, 1.0 - CANVAS_PADDING * graph_ratio))
+    
+        self.Figure.subplots_adjust()
+    
+    def GetCanvasMinSize(self):
+        return wx.Size(200, 
+                       CANVAS_BORDER[0] + CANVAS_BORDER[1] + 
+                       2 * CANVAS_PADDING + VALUE_LABEL_HEIGHT * len(self.Items))
+    
+    def SetCanvasSize(self, width, height):
+        height = max(height, self.GetCanvasMinSize()[1])
+        self.SetMinSize(wx.Size(width, height))
+        self.RefreshLabelsPosition(height)
+        self.RefreshButtonsState()
+        self.ParentWindow.RefreshGraphicsSizer()
+        
+    def GetAxesBoundingBox(self, absolute=False):
+        width, height = self.GetSize()
+        ax, ay, aw, ah = self.figure.gca().get_position().bounds
+        bbox = wx.Rect(ax * width, height - (ay + ah) * height - 1,
+                       aw * width + 2, ah * height + 1)
+        if absolute:
+            xw, yw = self.GetPosition()
+            bbox.x += xw
+            bbox.y += yw
+        return bbox
+    
+    def OnCanvasButtonPressed(self, event):
+        width, height = self.GetSize()
+        x, y = event.x, height - event.y
+        if not self.IsOverButton(x, y):
+            if event.inaxes == self.Axes:
+                item_idx = None
+                for i, t in ([pair for pair in enumerate(self.AxesLabels)] + 
+                             [pair for pair in enumerate(self.Labels)]):
+                    (x0, y0), (x1, y1) = t.get_window_extent().get_points()
+                    rect = wx.Rect(x0, height - y1, x1 - x0, y1 - y0)
+                    if rect.InsideXY(x, y):
+                        item_idx = i
+                        break
+                if item_idx is not None:
+                    self.ShowButtons(False)
+                    self.DismissContextualButtons()
+                    xw, yw = self.GetPosition()
+                    self.ParentWindow.StartDragNDrop(self, 
+                        self.Items[item_idx], x + xw, y + yw, x + xw, y + yw)
+                elif not self.Is3DCanvas():
+                    self.MouseStartPos = wx.Point(x, y)
+                    if event.button == 1 and event.inaxes == self.Axes:
+                        self.StartCursorTick = self.CursorTick
+                        self.HandleCursorMove(event)
+                    elif event.button == 2 and self.GraphType == GRAPH_PARALLEL:
+                        width, height = self.GetSize()
+                        start_tick, end_tick = self.ParentWindow.GetRange()
+                        self.StartCursorTick = start_tick
+            
+            elif event.button == 1 and event.y <= 5:
+                self.MouseStartPos = wx.Point(x, y)
+                self.CanvasStartSize = self.GetSize()
+    
+    def OnCanvasButtonReleased(self, event):
+        if self.ParentWindow.IsDragging():
+            width, height = self.GetSize()
+            xw, yw = self.GetPosition()
+            self.ParentWindow.StopDragNDrop(
+                self.ParentWindow.DraggingAxesPanel.Items[0].GetVariable(),
+                xw + event.x, 
+                yw + height - event.y)
+        else:
+            self.MouseStartPos = None
+            self.StartCursorTick = None
+            self.CanvasStartSize = None
+            width, height = self.GetSize()
+            self.HandleButtons(event.x, height - event.y)
+            if event.y > 5 and self.SetHighlight(HIGHLIGHT_NONE):
+                self.SetCursor(wx.NullCursor)
+                self.ParentWindow.ForceRefresh()
+    
+    def OnCanvasMotion(self, event):
+        width, height = self.GetSize()
+        if self.ParentWindow.IsDragging():
+            xw, yw = self.GetPosition()
+            self.ParentWindow.MoveDragNDrop(
+                xw + event.x, 
+                yw + height - event.y)
+        else:
+            if not self.Is3DCanvas():
+                if event.button == 1 and self.CanvasStartSize is None:
+                    if event.inaxes == self.Axes:
+                        if self.MouseStartPos is not None:
+                            self.HandleCursorMove(event)
+                    elif self.MouseStartPos is not None and len(self.Items) == 1:
+                        xw, yw = self.GetPosition()
+                        self.ParentWindow.SetCursorTick(self.StartCursorTick)
+                        self.ParentWindow.StartDragNDrop(self, 
+                            self.Items[0],
+                            event.x + xw, height - event.y + yw, 
+                            self.MouseStartPos.x + xw, self.MouseStartPos.y + yw)
+                elif event.button == 2 and self.GraphType == GRAPH_PARALLEL and self.MouseStartPos is not None:
+                    start_tick, end_tick = self.ParentWindow.GetRange()
+                    rect = self.GetAxesBoundingBox()
+                    self.ParentWindow.SetCanvasPosition(
+                        self.StartCursorTick + (self.MouseStartPos.x - event.x) *
+                        (end_tick - start_tick) / rect.width)    
+            
+            if event.button == 1 and self.CanvasStartSize is not None:
+                width, height = self.GetSize()
+                self.SetCanvasSize(width, 
+                    self.CanvasStartSize.height + height - event.y - self.MouseStartPos.y)
+                
+            elif event.button in [None, "up", "down"]:
+                if self.GraphType == GRAPH_PARALLEL:
+                    orientation = [wx.RIGHT] * len(self.AxesLabels) + [wx.LEFT] * len(self.Labels)
+                elif len(self.AxesLabels) > 0:
+                    orientation = [wx.RIGHT, wx.TOP, wx.LEFT, wx.BOTTOM]
+                else:
+                    orientation = [wx.LEFT] * len(self.Labels)
+                item_idx = None
+                item_style = None
+                for (i, t), style in zip([pair for pair in enumerate(self.AxesLabels)] + 
+                                         [pair for pair in enumerate(self.Labels)], 
+                                         orientation):
+                    (x0, y0), (x1, y1) = t.get_window_extent().get_points()
+                    rect = wx.Rect(x0, height - y1, x1 - x0, y1 - y0)
+                    if rect.InsideXY(event.x, height - event.y):
+                        item_idx = i
+                        item_style = style
+                        break
+                if item_idx is not None:
+                    self.PopupContextualButtons(self.Items[item_idx], rect, item_style)
+                    return 
+                if not self.IsOverContextualButton(event.x, height - event.y):
+                    self.DismissContextualButtons()
+                
+                if event.y <= 5:
+                    if self.SetHighlight(HIGHLIGHT_RESIZE):
+                        self.SetCursor(wx.StockCursor(wx.CURSOR_SIZENS))
+                        self.ParentWindow.ForceRefresh()
+                else:
+                    if self.SetHighlight(HIGHLIGHT_NONE):
+                        self.SetCursor(wx.NullCursor)
+                        self.ParentWindow.ForceRefresh()
+    
+    def OnCanvasScroll(self, event):
+        if event.inaxes is not None and event.guiEvent.ControlDown():
+            if self.GraphType == GRAPH_ORTHOGONAL:
+                start_tick, end_tick = self.ParentWindow.GetRange()
+                tick = (start_tick + end_tick) / 2.
+            else:
+                tick = event.xdata
+            self.ParentWindow.ChangeRange(int(-event.step) / 3, tick)
+            self.ParentWindow.VetoScrollEvent = True
+    
+    def OnDragging(self, x, y):
+        width, height = self.GetSize()
+        bbox = self.GetAxesBoundingBox()
+        if bbox.InsideXY(x, y) and not self.Is3DCanvas():
+            rect = wx.Rect(bbox.x, bbox.y, bbox.width / 2, bbox.height)
+            if rect.InsideXY(x, y):
+                self.SetHighlight(HIGHLIGHT_LEFT)
+            else:
+                self.SetHighlight(HIGHLIGHT_RIGHT)
+        elif y < height / 2:
+            if self.ParentWindow.IsViewerFirst(self):
+                self.SetHighlight(HIGHLIGHT_BEFORE)
+            else:
+                self.SetHighlight(HIGHLIGHT_NONE)
+                self.ParentWindow.HighlightPreviousViewer(self)
+        else:
+            self.SetHighlight(HIGHLIGHT_AFTER)
+    
+    def OnLeave(self, event):
+        if self.CanvasStartSize is None and self.SetHighlight(HIGHLIGHT_NONE):
+            self.SetCursor(wx.NullCursor)
+            self.ParentWindow.ForceRefresh()
+        DebugVariableViewer.OnLeave(self, event)
+    
+    KEY_CURSOR_INCREMENT = {
+        wx.WXK_LEFT: -1,
+        wx.WXK_RIGHT: 1,
+        wx.WXK_UP: -10,
+        wx.WXK_DOWN: 10}
+    def OnKeyDown(self, event):
+        if self.CursorTick is not None:
+            move = self.KEY_CURSOR_INCREMENT.get(event.GetKeyCode(), None)
+            if move is not None:
+                self.ParentWindow.MoveCursorTick(move)
+        event.Skip()
+    
+    def HandleCursorMove(self, event):
+        start_tick, end_tick = self.ParentWindow.GetRange()
+        cursor_tick = None
+        if self.GraphType == GRAPH_ORTHOGONAL:
+            x_data = self.Items[0].GetData(start_tick, end_tick)
+            y_data = self.Items[1].GetData(start_tick, end_tick)
+            if len(x_data) > 0 and len(y_data) > 0:
+                length = min(len(x_data), len(y_data))
+                d = numpy.sqrt((x_data[:length,1]-event.xdata) ** 2 + (y_data[:length,1]-event.ydata) ** 2)
+                cursor_tick = x_data[numpy.argmin(d), 0]
+        else:
+            data = self.Items[0].GetData(start_tick, end_tick)
+            if len(data) > 0:
+                cursor_tick = data[numpy.argmin(numpy.abs(data[:,0] - event.xdata)), 0]
+        if cursor_tick is not None:
+            self.ParentWindow.SetCursorTick(cursor_tick)
+    
+    def OnAxesMotion(self, event):
+        if self.Is3DCanvas():
+            current_time = gettime()
+            if current_time - self.LastMotionTime > REFRESH_PERIOD:
+                self.LastMotionTime = current_time
+                Axes3D._on_move(self.Axes, event)
+    
+    def ResetGraphics(self):
+        self.Figure.clear()
+        if self.Is3DCanvas():
+            self.Axes = self.Figure.gca(projection='3d')
+            self.Axes.set_color_cycle(['b'])
+            self.LastMotionTime = gettime()
+            setattr(self.Axes, "_on_move", self.OnAxesMotion)
+            self.Axes.mouse_init()
+            self.Axes.tick_params(axis='z', labelsize='small')
+        else:
+            self.Axes = self.Figure.gca()
+            self.Axes.set_color_cycle(color_cycle)
+        self.Axes.tick_params(axis='x', labelsize='small')
+        self.Axes.tick_params(axis='y', labelsize='small')
+        self.Plots = []
+        self.VLine = None
+        self.HLine = None
+        self.Labels = []
+        self.AxesLabels = []
+        if not self.Is3DCanvas():
+            text_func = self.Axes.text
+        else:
+            text_func = self.Axes.text2D
+        if self.GraphType == GRAPH_PARALLEL or self.Is3DCanvas():
+            num_item = len(self.Items)
+            for idx in xrange(num_item):
+                if num_item == 1:
+                    color = 'k'
+                else:
+                    color = color_cycle[idx % len(color_cycle)]
+                if not self.Is3DCanvas():
+                    self.AxesLabels.append(
+                        text_func(0, 0, "", size='small',
+                                  verticalalignment='top', 
+                                  color=color,
+                                  transform=self.Axes.transAxes))
+                self.Labels.append(
+                    text_func(0, 0, "", size='large', 
+                              horizontalalignment='right',
+                              color=color,
+                              transform=self.Axes.transAxes))
+        else:
+            self.AxesLabels.append(
+                self.Axes.text(0, 0, "", size='small',
+                               transform=self.Axes.transAxes))
+            self.Labels.append(
+                self.Axes.text(0, 0, "", size='large',
+                               horizontalalignment='right',
+                               transform=self.Axes.transAxes))
+            self.AxesLabels.append(
+                self.Axes.text(0, 0, "", size='small',
+                               rotation='vertical',
+                               verticalalignment='bottom',
+                               transform=self.Axes.transAxes))
+            self.Labels.append(
+                self.Axes.text(0, 0, "", size='large',
+                               rotation='vertical',
+                               verticalalignment='top',
+                               transform=self.Axes.transAxes))
+        width, height = self.GetSize()
+        self.RefreshLabelsPosition(height)
+        
+    def AddItem(self, item):
+        DebugVariableViewer.AddItem(self, item)
+        self.ResetGraphics()
+        
+    def RemoveItem(self, item):
+        DebugVariableViewer.RemoveItem(self, item)
+        if not self.IsEmpty():
+            if len(self.Items) == 1:
+                self.GraphType = GRAPH_PARALLEL
+            self.ResetGraphics()
+    
+    def UnregisterObsoleteData(self):
+        DebugVariableViewer.UnregisterObsoleteData(self)
+        if not self.IsEmpty():
+            self.ResetGraphics()
+    
+    def Is3DCanvas(self):
+        return self.GraphType == GRAPH_ORTHOGONAL and len(self.Items) == 3
+    
+    def SetCursorTick(self, cursor_tick):
+        self.CursorTick = cursor_tick
+        
+    def RefreshViewer(self, refresh_graphics=True):
+        
+        if refresh_graphics:
+            start_tick, end_tick = self.ParentWindow.GetRange()
+            
+            if self.GraphType == GRAPH_PARALLEL:    
+                min_value = max_value = None
+                
+                for idx, item in enumerate(self.Items):
+                    data = item.GetData(start_tick, end_tick)
+                    if data is not None:
+                        item_min_value, item_max_value = item.GetValueRange()
+                        if min_value is None:
+                            min_value = item_min_value
+                        elif item_min_value is not None:
+                            min_value = min(min_value, item_min_value)
+                        if max_value is None:
+                            max_value = item_max_value
+                        elif item_max_value is not None:
+                            max_value = max(max_value, item_max_value)
+                        
+                        if len(self.Plots) <= idx:
+                            self.Plots.append(
+                                self.Axes.plot(data[:, 0], data[:, 1])[0])
+                        else:
+                            self.Plots[idx].set_data(data[:, 0], data[:, 1])
+                    
+                if min_value is not None and max_value is not None:
+                    y_center = (min_value + max_value) / 2.
+                    y_range = max(1.0, max_value - min_value)
+                else:
+                    y_center = 0.5
+                    y_range = 1.0
+                x_min, x_max = start_tick, end_tick
+                y_min, y_max = y_center - y_range * 0.55, y_center + y_range * 0.55
+                
+                if self.CursorTick is not None and start_tick <= self.CursorTick <= end_tick:
+                    if self.VLine is None:
+                        self.VLine = self.Axes.axvline(self.CursorTick, color=cursor_color)
+                    else:
+                        self.VLine.set_xdata((self.CursorTick, self.CursorTick))
+                    self.VLine.set_visible(True)
+                else:
+                    if self.VLine is not None:
+                        self.VLine.set_visible(False)
+            else:
+                min_start_tick = reduce(max, [item.GetData()[0, 0] 
+                                              for item in self.Items
+                                              if len(item.GetData()) > 0], 0)
+                start_tick = max(start_tick, min_start_tick)
+                end_tick = max(end_tick, min_start_tick)
+                x_data, x_min, x_max = OrthogonalData(self.Items[0], start_tick, end_tick)
+                y_data, y_min, y_max = OrthogonalData(self.Items[1], start_tick, end_tick)
+                if self.CursorTick is not None:
+                    x_cursor, x_forced = self.Items[0].GetValue(self.CursorTick, raw=True)
+                    y_cursor, y_forced = self.Items[1].GetValue(self.CursorTick, raw=True)
+                length = 0
+                if x_data is not None and y_data is not None:  
+                    length = min(len(x_data), len(y_data))
+                if len(self.Items) < 3:
+                    if x_data is not None and y_data is not None:
+                        if len(self.Plots) == 0:
+                            self.Plots.append(
+                                self.Axes.plot(x_data[:, 1][:length], 
+                                               y_data[:, 1][:length])[0])
+                        else:
+                            self.Plots[0].set_data(
+                                x_data[:, 1][:length], 
+                                y_data[:, 1][:length])
+                    
+                    if self.CursorTick is not None and start_tick <= self.CursorTick <= end_tick:
+                        if self.VLine is None:
+                            self.VLine = self.Axes.axvline(x_cursor, color=cursor_color)
+                        else:
+                            self.VLine.set_xdata((x_cursor, x_cursor))
+                        if self.HLine is None:
+                            self.HLine = self.Axes.axhline(y_cursor, color=cursor_color)
+                        else:
+                            self.HLine.set_ydata((y_cursor, y_cursor))
+                        self.VLine.set_visible(True)
+                        self.HLine.set_visible(True)
+                    else:
+                        if self.VLine is not None:
+                            self.VLine.set_visible(False)
+                        if self.HLine is not None:
+                            self.HLine.set_visible(False)
+                else:
+                    while len(self.Axes.lines) > 0:
+                        self.Axes.lines.pop()
+                    z_data, z_min, z_max = OrthogonalData(self.Items[2], start_tick, end_tick)
+                    if self.CursorTick is not None:
+                        z_cursor, z_forced = self.Items[2].GetValue(self.CursorTick, raw=True)
+                    if x_data is not None and y_data is not None and z_data is not None:
+                        length = min(length, len(z_data))
+                        self.Axes.plot(x_data[:, 1][:length],
+                                       y_data[:, 1][:length],
+                                       zs = z_data[:, 1][:length])
+                    self.Axes.set_zlim(z_min, z_max)
+                    if self.CursorTick is not None and start_tick <= self.CursorTick <= end_tick:
+                        for kwargs in [{"xs": numpy.array([x_min, x_max])},
+                                       {"ys": numpy.array([y_min, y_max])},
+                                       {"zs": numpy.array([z_min, z_max])}]:
+                            for param, value in [("xs", numpy.array([x_cursor, x_cursor])),
+                                                 ("ys", numpy.array([y_cursor, y_cursor])),
+                                                 ("zs", numpy.array([z_cursor, z_cursor]))]:
+                                kwargs.setdefault(param, value)
+                            kwargs["color"] = cursor_color
+                            self.Axes.plot(**kwargs)
+                
+            self.Axes.set_xlim(x_min, x_max)
+            self.Axes.set_ylim(y_min, y_max)
+        
+        variable_name_mask = self.ParentWindow.GetVariableNameMask()
+        if self.CursorTick is not None:
+            values, forced = apply(zip, [item.GetValue(self.CursorTick) for item in self.Items])
+        else:
+            values, forced = apply(zip, [(item.GetValue(), item.IsForced()) for item in self.Items])
+        labels = [item.GetVariable(variable_name_mask) for item in self.Items]
+        styles = map(lambda x: {True: 'italic', False: 'normal'}[x], forced)
+        if self.Is3DCanvas():
+            for idx, label_func in enumerate([self.Axes.set_xlabel, 
+                                              self.Axes.set_ylabel,
+                                              self.Axes.set_zlabel]):
+                label_func(labels[idx], fontdict={'size': 'small','color': color_cycle[idx]})
+        else:
+            for label, text in zip(self.AxesLabels, labels):
+                label.set_text(text)
+        for label, value, style in zip(self.Labels, values, styles):
+            label.set_text(value)
+            label.set_style(style)
+        
+        self.draw()
+
+    def ExportGraph(self, item=None):
+        if item is not None:
+            variables = [(item, [entry for entry in item.GetData()])]
+        else:
+            variables = [(item, [entry for entry in item.GetData()])
+                         for item in self.Items]
+        self.ParentWindow.CopyDataToClipboard(variables)
+    
+class DebugVariableGraphicPanel(wx.Panel, DebugViewer):
+    
+    def __init__(self, parent, producer, window):
+        wx.Panel.__init__(self, parent, style=wx.SP_3D|wx.TAB_TRAVERSAL)
+        
+        self.ParentWindow = window
+        
+        self.HasNewData = False
+        self.Force = False
+        
+        self.SetBackgroundColour(wx.WHITE)
+        
+        main_sizer = wx.BoxSizer(wx.VERTICAL)
+        
+        self.Ticks = numpy.array([])
+        self.StartTick = 0
+        self.Fixed = False
+        self.CursorTick = None
+        self.DraggingAxesPanel = None
+        self.DraggingAxesBoundingBox = None
+        self.DraggingAxesMousePos = None
+        self.VetoScrollEvent = False
+        self.VariableNameMask = []
+        
+        self.GraphicPanels = []
+        
+        graphics_button_sizer = wx.BoxSizer(wx.HORIZONTAL)
+        main_sizer.AddSizer(graphics_button_sizer, border=5, flag=wx.GROW|wx.ALL)
+        
+        range_label = wx.StaticText(self, label=_('Range:'))
+        graphics_button_sizer.AddWindow(range_label, flag=wx.ALIGN_CENTER_VERTICAL)
+        
+        self.CanvasRange = wx.ComboBox(self, style=wx.CB_READONLY)
+        self.Bind(wx.EVT_COMBOBOX, self.OnRangeChanged, self.CanvasRange)
+        graphics_button_sizer.AddWindow(self.CanvasRange, 1, 
+              border=5, flag=wx.LEFT|wx.ALIGN_CENTER_VERTICAL)
+        
+        self.CanvasRange.Clear()
+        default_range_idx = 0
+        for idx, (text, value) in enumerate(RANGE_VALUES):
+            self.CanvasRange.Append(text)
+            if text == "1s":
+                default_range_idx = idx
+        self.CanvasRange.SetSelection(default_range_idx)
+        
+        for name, bitmap, help in [
+            ("CurrentButton", "current", _("Go to current value")),
+            ("ExportGraphButton", "export_graph", _("Export graph values to clipboard"))]:
+            button = wx.lib.buttons.GenBitmapButton(self, 
+                  bitmap=GetBitmap(bitmap), 
+                  size=wx.Size(28, 28), style=wx.NO_BORDER)
+            button.SetToolTipString(help)
+            setattr(self, name, button)
+            self.Bind(wx.EVT_BUTTON, getattr(self, "On" + name), button)
+            graphics_button_sizer.AddWindow(button, border=5, flag=wx.LEFT)
+        
+        self.CanvasPosition = wx.ScrollBar(self, 
+              size=wx.Size(0, 16), style=wx.SB_HORIZONTAL)
+        self.CanvasPosition.Bind(wx.EVT_SCROLL_THUMBTRACK, 
+              self.OnPositionChanging, self.CanvasPosition)
+        self.CanvasPosition.Bind(wx.EVT_SCROLL_LINEUP, 
+              self.OnPositionChanging, self.CanvasPosition)
+        self.CanvasPosition.Bind(wx.EVT_SCROLL_LINEDOWN, 
+              self.OnPositionChanging, self.CanvasPosition)
+        self.CanvasPosition.Bind(wx.EVT_SCROLL_PAGEUP, 
+              self.OnPositionChanging, self.CanvasPosition)
+        self.CanvasPosition.Bind(wx.EVT_SCROLL_PAGEDOWN, 
+              self.OnPositionChanging, self.CanvasPosition)
+        main_sizer.AddWindow(self.CanvasPosition, border=5, flag=wx.GROW|wx.LEFT|wx.RIGHT|wx.BOTTOM)
+        
+        self.TickSizer = wx.BoxSizer(wx.HORIZONTAL)
+        main_sizer.AddSizer(self.TickSizer, border=5, flag=wx.ALL|wx.GROW)
+        
+        self.TickLabel = wx.StaticText(self)
+        self.TickSizer.AddWindow(self.TickLabel, border=5, flag=wx.RIGHT)
+        
+        self.MaskLabel = wx.TextCtrl(self, style=wx.TE_READONLY|wx.TE_CENTER|wx.NO_BORDER)
+        self.TickSizer.AddWindow(self.MaskLabel, 1, border=5, flag=wx.RIGHT|wx.GROW)
+        
+        self.TickTimeLabel = wx.StaticText(self)
+        self.TickSizer.AddWindow(self.TickTimeLabel)
+        
+        self.GraphicsWindow = wx.ScrolledWindow(self, style=wx.HSCROLL|wx.VSCROLL)
+        self.GraphicsWindow.SetBackgroundColour(wx.WHITE)
+        self.GraphicsWindow.SetDropTarget(DebugVariableDropTarget(self))
+        self.GraphicsWindow.Bind(wx.EVT_ERASE_BACKGROUND, self.OnGraphicsWindowEraseBackground)
+        self.GraphicsWindow.Bind(wx.EVT_PAINT, self.OnGraphicsWindowPaint)
+        self.GraphicsWindow.Bind(wx.EVT_SIZE, self.OnGraphicsWindowResize)
+        self.GraphicsWindow.Bind(wx.EVT_MOUSEWHEEL, self.OnGraphicsWindowMouseWheel)
+        
+        main_sizer.AddWindow(self.GraphicsWindow, 1, flag=wx.GROW)
+        
+        self.GraphicsSizer = wx.BoxSizer(wx.VERTICAL)
+        self.GraphicsWindow.SetSizer(self.GraphicsSizer)
+    
+        DebugViewer.__init__(self, producer, True)
+        
+        self.SetSizer(main_sizer)
+    
+    def SetTickTime(self, ticktime=0):
+        self.Ticktime = ticktime
+        if self.Ticktime == 0:
+            self.Ticktime = MILLISECOND
+        self.CurrentRange = RANGE_VALUES[
+            self.CanvasRange.GetSelection()][1] / self.Ticktime
+    
+    def SetDataProducer(self, producer):
+        DebugViewer.SetDataProducer(self, producer)
+        
+        if self.DataProducer is not None:
+            self.SetTickTime(self.DataProducer.GetTicktime())
+    
+    def RefreshNewData(self, *args, **kwargs):
+        if self.HasNewData or self.Force:
+            self.HasNewData = False
+            self.RefreshView()
+        DebugViewer.RefreshNewData(self, *args, **kwargs)
+    
+    def NewDataAvailable(self, tick, *args, **kwargs):
+        if tick is not None:
+            if len(self.Ticks) == 0:
+                self.StartTick = tick 
+            self.Ticks = numpy.append(self.Ticks, [tick])
+            if not self.Fixed or tick < self.StartTick + self.CurrentRange:
+                self.StartTick = max(self.StartTick, tick - self.CurrentRange)
+            if self.Fixed and self.Ticks[-1] - self.Ticks[0] < self.CurrentRange:
+                self.Force = True
+        DebugViewer.NewDataAvailable(self, tick, *args, **kwargs)
+    
+    def ForceRefresh(self):
+        self.Force = True
+        wx.CallAfter(self.NewDataAvailable, None, True)
+    
+    def RefreshGraphicsSizer(self):
+        self.GraphicsSizer.Clear()
+        
+        for panel in self.GraphicPanels:
+            self.GraphicsSizer.AddWindow(panel, flag=wx.GROW)
+            
+        self.GraphicsSizer.Layout()
+        self.RefreshGraphicsWindowScrollbars()
+    
+    def SetCanvasPosition(self, tick):
+        tick = max(self.Ticks[0], min(tick, self.Ticks[-1] - self.CurrentRange))
+        self.StartTick = self.Ticks[numpy.argmin(numpy.abs(self.Ticks - tick))]
+        self.Fixed = True
+        self.RefreshCanvasPosition()
+        self.ForceRefresh()
+    
+    def SetCursorTick(self, cursor_tick):
+        self.CursorTick = cursor_tick
+        self.Fixed = True
+        self.UpdateCursorTick() 
+    
+    def MoveCursorTick(self, move):
+        if self.CursorTick is not None:
+            cursor_tick = max(self.Ticks[0], 
+                          min(self.CursorTick + move, 
+                              self.Ticks[-1]))
+            cursor_tick_idx = numpy.argmin(numpy.abs(self.Ticks - cursor_tick))
+            if self.Ticks[cursor_tick_idx] == self.CursorTick:
+                cursor_tick_idx = max(0, 
+                                  min(cursor_tick_idx + abs(move) / move, 
+                                      len(self.Ticks) - 1))
+            self.CursorTick = self.Ticks[cursor_tick_idx]
+            self.StartTick = max(self.Ticks[
+                                numpy.argmin(numpy.abs(self.Ticks - 
+                                        self.CursorTick + self.CurrentRange))],
+                             min(self.StartTick, self.CursorTick))
+            self.RefreshCanvasPosition()
+            self.UpdateCursorTick() 
+            
+    def ResetCursorTick(self):
+        self.CursorTick = None
+        self.UpdateCursorTick()
+    
+    def UpdateCursorTick(self):
+        for panel in self.GraphicPanels:
+            if isinstance(panel, DebugVariableGraphic):
+                panel.SetCursorTick(self.CursorTick)
+        self.ForceRefresh()
+    
+    def StartDragNDrop(self, panel, item, x_mouse, y_mouse, x_mouse_start, y_mouse_start):
+        if len(panel.GetItems()) > 1:
+            self.DraggingAxesPanel = DebugVariableGraphic(self.GraphicsWindow, self, [item], GRAPH_PARALLEL)
+            self.DraggingAxesPanel.SetCursorTick(self.CursorTick)
+            width, height = panel.GetSize()
+            self.DraggingAxesPanel.SetSize(wx.Size(width, height))
+            self.DraggingAxesPanel.ResetGraphics()
+            self.DraggingAxesPanel.SetPosition(wx.Point(0, -height))
+        else:
+            self.DraggingAxesPanel = panel
+        self.DraggingAxesBoundingBox = panel.GetAxesBoundingBox(absolute=True)
+        self.DraggingAxesMousePos = wx.Point(
+            x_mouse_start - self.DraggingAxesBoundingBox.x, 
+            y_mouse_start - self.DraggingAxesBoundingBox.y)
+        self.MoveDragNDrop(x_mouse, y_mouse)
+        
+    def MoveDragNDrop(self, x_mouse, y_mouse):
+        self.DraggingAxesBoundingBox.x = x_mouse - self.DraggingAxesMousePos.x
+        self.DraggingAxesBoundingBox.y = y_mouse - self.DraggingAxesMousePos.y
+        self.RefreshHighlight(x_mouse, y_mouse)
+    
+    def RefreshHighlight(self, x_mouse, y_mouse):
+        for idx, panel in enumerate(self.GraphicPanels):
+            x, y = panel.GetPosition()
+            width, height = panel.GetSize()
+            rect = wx.Rect(x, y, width, height)
+            if (rect.InsideXY(x_mouse, y_mouse) or 
+                idx == 0 and y_mouse < 0 or
+                idx == len(self.GraphicPanels) - 1 and y_mouse > panel.GetPosition()[1]):
+                panel.OnDragging(x_mouse - x, y_mouse - y)
+            else:
+                panel.SetHighlight(HIGHLIGHT_NONE)
+        if wx.Platform == "__WXMSW__":
+            self.RefreshView()
+        else:
+            self.ForceRefresh()
+    
+    def ResetHighlight(self):
+        for panel in self.GraphicPanels:
+            panel.SetHighlight(HIGHLIGHT_NONE)
+        if wx.Platform == "__WXMSW__":
+            self.RefreshView()
+        else:
+            self.ForceRefresh()
+    
+    def IsDragging(self):
+        return self.DraggingAxesPanel is not None
+    
+    def GetDraggingAxesClippingRegion(self, panel):
+        x, y = panel.GetPosition()
+        width, height = panel.GetSize()
+        bbox = wx.Rect(x, y, width, height)
+        bbox = bbox.Intersect(self.DraggingAxesBoundingBox)
+        bbox.x -= x
+        bbox.y -= y
+        return bbox
+    
+    def GetDraggingAxesPosition(self, panel):
+        x, y = panel.GetPosition()
+        return wx.Point(self.DraggingAxesBoundingBox.x - x,
+                        self.DraggingAxesBoundingBox.y - y)
+    
+    def StopDragNDrop(self, variable, x_mouse, y_mouse):
+        if self.DraggingAxesPanel not in self.GraphicPanels:
+            self.DraggingAxesPanel.Destroy()
+        self.DraggingAxesPanel = None
+        self.DraggingAxesBoundingBox = None
+        self.DraggingAxesMousePos = None
+        for idx, panel in enumerate(self.GraphicPanels):
+            panel.SetHighlight(HIGHLIGHT_NONE)
+            xw, yw = panel.GetPosition()
+            width, height = panel.GetSize()
+            bbox = wx.Rect(xw, yw, width, height)
+            if bbox.InsideXY(x_mouse, y_mouse):
+                panel.ShowButtons(True)
+                merge_type = GRAPH_PARALLEL
+                if isinstance(panel, DebugVariableText) or panel.Is3DCanvas():
+                    if y_mouse > yw + height / 2:
+                        idx += 1
+                    wx.CallAfter(self.MoveValue, variable, idx)
+                else:
+                    rect = panel.GetAxesBoundingBox(True)
+                    if rect.InsideXY(x_mouse, y_mouse):
+                        merge_rect = wx.Rect(rect.x, rect.y, rect.width / 2., rect.height)
+                        if merge_rect.InsideXY(x_mouse, y_mouse):
+                            merge_type = GRAPH_ORTHOGONAL
+                        wx.CallAfter(self.MergeGraphs, variable, idx, merge_type, force=True)
+                    else:
+                        if y_mouse > yw + height / 2:
+                            idx += 1
+                        wx.CallAfter(self.MoveValue, variable, idx)
+                self.ForceRefresh()
+                return 
+        width, height = self.GraphicsWindow.GetVirtualSize()
+        rect = wx.Rect(0, 0, width, height)
+        if rect.InsideXY(x_mouse, y_mouse):
+            wx.CallAfter(self.MoveValue, variable, len(self.GraphicPanels))
+        self.ForceRefresh()
+    
+    def RefreshView(self):
+        self.RefreshCanvasPosition()
+        
+        width, height = self.GraphicsWindow.GetVirtualSize()
+        bitmap = wx.EmptyBitmap(width, height)
+        dc = wx.BufferedDC(wx.ClientDC(self.GraphicsWindow), bitmap)
+        dc.Clear()
+        dc.BeginDrawing()
+        if self.DraggingAxesPanel is not None:
+            destBBox = self.DraggingAxesBoundingBox
+            srcBBox = self.DraggingAxesPanel.GetAxesBoundingBox()
+            
+            srcBmp = _convert_agg_to_wx_bitmap(self.DraggingAxesPanel.get_renderer(), None)
+            srcDC = wx.MemoryDC()
+            srcDC.SelectObject(srcBmp)
+                
+            dc.Blit(destBBox.x, destBBox.y, 
+                    int(destBBox.width), int(destBBox.height), 
+                    srcDC, srcBBox.x, srcBBox.y)
+        dc.EndDrawing()
+        
+        if not self.Fixed or self.Force:
+            self.Force = False
+            refresh_graphics = True
+        else:
+            refresh_graphics = False
+        
+        if self.DraggingAxesPanel is not None and self.DraggingAxesPanel not in self.GraphicPanels:
+            self.DraggingAxesPanel.RefreshViewer(refresh_graphics)
+        for panel in self.GraphicPanels:
+            if isinstance(panel, DebugVariableGraphic):
+                panel.RefreshViewer(refresh_graphics)
+            else:
+                panel.RefreshViewer()
+        
+        if self.CursorTick is not None:
+            tick = self.CursorTick
+        elif len(self.Ticks) > 0:
+            tick = self.Ticks[-1]
+        else:
+            tick = None
+        if tick is not None:
+            self.TickLabel.SetLabel("Tick: %d" % tick)
+            tick_duration = int(tick * self.Ticktime)
+            not_null = False
+            duration = ""
+            for value, format in [(tick_duration / DAY, "%dd"),
+                                  ((tick_duration % DAY) / HOUR, "%dh"),
+                                  ((tick_duration % HOUR) / MINUTE, "%dm"),
+                                  ((tick_duration % MINUTE) / SECOND, "%ds")]:
+                
+                if value > 0 or not_null:
+                    duration += format % value
+                    not_null = True
+            
+            duration += "%gms" % (float(tick_duration % SECOND) / MILLISECOND) 
+            self.TickTimeLabel.SetLabel("t: %s" % duration)
+        else:
+            self.TickLabel.SetLabel("")
+            self.TickTimeLabel.SetLabel("")
+        self.TickSizer.Layout()
+    
+    def UnregisterObsoleteData(self):
+        self.SubscribeAllDataConsumers()
+        
+        if self.DataProducer is not None:
+            if self.DataProducer is not None:
+                self.SetTickTime(self.DataProducer.GetTicktime())
+        
+        for panel in self.GraphicPanels:
+            panel.UnregisterObsoleteData()
+            if panel.IsEmpty():
+                if panel.HasCapture():
+                    panel.ReleaseMouse()
+                self.GraphicPanels.remove(panel)
+                panel.Destroy()
+        
+        self.ResetVariableNameMask()
+        self.RefreshGraphicsSizer()
+        self.ForceRefresh()
+    
+    def ResetView(self):
+        self.UnsubscribeAllDataConsumers()
+        
+        self.Fixed = False
+        for panel in self.GraphicPanels:
+            panel.Destroy()
+        self.GraphicPanels = []
+        self.ResetVariableNameMask()
+        self.RefreshGraphicsSizer()
+    
+    def RefreshCanvasPosition(self):
+        if len(self.Ticks) > 0:
+            pos = int(self.StartTick - self.Ticks[0])
+            range = int(self.Ticks[-1] - self.Ticks[0])
+        else:
+            pos = 0
+            range = 0
+        self.CanvasPosition.SetScrollbar(pos, self.CurrentRange, range, self.CurrentRange)
+    
+    def ChangeRange(self, dir, tick=None):
+        current_range = self.CurrentRange
+        current_range_idx = self.CanvasRange.GetSelection()
+        new_range_idx = max(0, min(current_range_idx + dir, len(RANGE_VALUES) - 1))
+        if new_range_idx != current_range_idx:
+            self.CanvasRange.SetSelection(new_range_idx)
+            self.CurrentRange = RANGE_VALUES[new_range_idx][1] / self.Ticktime
+            if len(self.Ticks) > 0:
+                if tick is None:
+                    tick = self.StartTick + self.CurrentRange / 2.
+                new_start_tick = tick - (tick - self.StartTick) * self.CurrentRange / current_range 
+                self.StartTick = self.Ticks[numpy.argmin(numpy.abs(self.Ticks - new_start_tick))]
+                self.Fixed = self.StartTick < self.Ticks[-1] - self.CurrentRange
+            self.ForceRefresh()
+    
+    def RefreshRange(self):
+        if len(self.Ticks) > 0:
+            if self.Fixed and self.Ticks[-1] - self.Ticks[0] < self.CurrentRange:
+                self.Fixed = False
+            if self.Fixed:
+                self.StartTick = min(self.StartTick, self.Ticks[-1] - self.CurrentRange)
+            else:
+                self.StartTick = max(self.Ticks[0], self.Ticks[-1] - self.CurrentRange)
+        self.ForceRefresh()
+    
+    def OnRangeChanged(self, event):
+        try:
+            self.CurrentRange = RANGE_VALUES[self.CanvasRange.GetSelection()][1] / self.Ticktime
+        except ValueError, e:
+            self.CanvasRange.SetValue(str(self.CurrentRange))
+        wx.CallAfter(self.RefreshRange)
+        event.Skip()
+    
+    def OnCurrentButton(self, event):
+        if len(self.Ticks) > 0:
+            self.StartTick = max(self.Ticks[0], self.Ticks[-1] - self.CurrentRange)
+            self.Fixed = False
+            self.ResetCursorTick()
+        event.Skip()
+    
+    def CopyDataToClipboard(self, variables):
+        text = "tick;%s;\n" % ";".join([item.GetVariable() for item, data in variables])
+        next_tick = NextTick(variables)
+        while next_tick is not None:
+            values = []
+            for item, data in variables:
+                if len(data) > 0:
+                    if next_tick == data[0][0]:
+                        var_type = item.GetVariableType()
+                        if var_type in ["STRING", "WSTRING"]:
+                            value = item.GetRawValue(int(data.pop(0)[2]))
+                            if var_type == "STRING":
+                                values.append("'%s'" % value)
+                            else:
+                                values.append('"%s"' % value)
+                        else:
+                            values.append("%.3f" % data.pop(0)[1])
+                    else:
+                        values.append("")
+                else:
+                    values.append("")
+            text += "%d;%s;\n" % (next_tick, ";".join(values))
+            next_tick = NextTick(variables)
+        self.ParentWindow.SetCopyBuffer(text)
+    
+    def OnExportGraphButton(self, event):
+        items = reduce(lambda x, y: x + y,
+                       [panel.GetItems() for panel in self.GraphicPanels],
+                       [])
+        variables = [(item, [entry for entry in item.GetData()])
+                     for item in items
+                     if item.IsNumVariable()]
+        wx.CallAfter(self.CopyDataToClipboard, variables)
+        event.Skip()
+    
+    def OnPositionChanging(self, event):
+        if len(self.Ticks) > 0:
+            self.StartTick = self.Ticks[0] + event.GetPosition()
+            self.Fixed = True
+            self.ForceRefresh()
+        event.Skip()
+    
+    def GetRange(self):
+        return self.StartTick, self.StartTick + self.CurrentRange
+    
+    def GetViewerIndex(self, viewer):
+        if viewer in self.GraphicPanels:
+            return self.GraphicPanels.index(viewer)
+        return None
+    
+    def IsViewerFirst(self, viewer):
+        return viewer == self.GraphicPanels[0]
+    
+    def IsViewerLast(self, viewer):
+        return viewer == self.GraphicPanels[-1]
+    
+    def HighlightPreviousViewer(self, viewer):
+        if self.IsViewerFirst(viewer):
+            return
+        idx = self.GetViewerIndex(viewer)
+        if idx is None:
+            return
+        self.GraphicPanels[idx-1].SetHighlight(HIGHLIGHT_AFTER)
+    
+    def ResetVariableNameMask(self):
+        items = []
+        for panel in self.GraphicPanels:
+            items.extend(panel.GetItems())
+        if len(items) > 1:
+            self.VariableNameMask = reduce(compute_mask,
+                [item.GetVariable().split('.') for item in items])
+        elif len(items) > 0:
+            self.VariableNameMask = items[0].GetVariable().split('.')[:-1] + ['*']
+        else:
+            self.VariableNameMask = []
+        self.MaskLabel.ChangeValue(".".join(self.VariableNameMask))
+        self.MaskLabel.SetInsertionPoint(self.MaskLabel.GetLastPosition())
+            
+    def GetVariableNameMask(self):
+        return self.VariableNameMask
+    
+    def InsertValue(self, iec_path, idx = None, force=False):
+        for panel in self.GraphicPanels:
+            if panel.GetItem(iec_path) is not None:
+                return
+        if idx is None:
+            idx = len(self.GraphicPanels)
+        item = DebugVariableItem(self, iec_path, True)
+        result = self.AddDataConsumer(iec_path.upper(), item)
+        if result is not None or force:
+            
+            if item.IsNumVariable():
+                panel = DebugVariableGraphic(self.GraphicsWindow, self, [item], GRAPH_PARALLEL)
+                if self.CursorTick is not None:
+                    panel.SetCursorTick(self.CursorTick)
+            else:
+                panel = DebugVariableText(self.GraphicsWindow, self, [item])
+            if idx is not None:
+                self.GraphicPanels.insert(idx, panel)
+            else:
+                self.GraphicPanels.append(panel)
+            self.ResetVariableNameMask()
+            self.RefreshGraphicsSizer()
+            self.ForceRefresh()
+    
+    def MoveValue(self, iec_path, idx = None):
+        if idx is None:
+            idx = len(self.GraphicPanels)
+        source_panel = None
+        item = None
+        for panel in self.GraphicPanels:
+            item = panel.GetItem(iec_path)
+            if item is not None:
+                source_panel = panel
+                break
+        if source_panel is not None:
+            source_panel.RemoveItem(item)
+            source_size = source_panel.GetSize()
+            if source_panel.IsEmpty():
+                if source_panel.HasCapture():
+                    source_panel.ReleaseMouse()
+                self.GraphicPanels.remove(source_panel)
+                source_panel.Destroy()
+            
+            if item.IsNumVariable():
+                panel = DebugVariableGraphic(self.GraphicsWindow, self, [item], GRAPH_PARALLEL)
+                panel.SetCanvasSize(source_size.width, source_size.height)
+                if self.CursorTick is not None:
+                    panel.SetCursorTick(self.CursorTick)
+            else:
+                panel = DebugVariableText(self.GraphicsWindow, self, [item])
+            self.GraphicPanels.insert(idx, panel)
+            self.ResetVariableNameMask()
+            self.RefreshGraphicsSizer()
+            self.ForceRefresh()
+    
+    def MergeGraphs(self, source, target_idx, merge_type, force=False):
+        source_item = None
+        source_panel = None
+        for panel in self.GraphicPanels:
+            source_item = panel.GetItem(source)
+            if source_item is not None:
+                source_panel = panel
+                break
+        if source_item is None:
+            item = DebugVariableItem(self, source, True)
+            if item.IsNumVariable():
+                result = self.AddDataConsumer(source.upper(), item)
+                if result is not None or force:
+                    source_item = item
+        if source_item is not None and source_item.IsNumVariable():
+            if source_panel is not None:
+                source_size = source_panel.GetSize()
+            else:
+                source_size = None
+            target_panel = self.GraphicPanels[target_idx]
+            graph_type = target_panel.GraphType
+            if target_panel != source_panel:
+                if (merge_type == GRAPH_PARALLEL and graph_type != merge_type or
+                    merge_type == GRAPH_ORTHOGONAL and 
+                    (graph_type == GRAPH_PARALLEL and len(target_panel.Items) > 1 or
+                     graph_type == GRAPH_ORTHOGONAL and len(target_panel.Items) >= 3)):
+                    return
+                
+                if source_panel is not None:
+                    source_panel.RemoveItem(source_item)
+                    if source_panel.IsEmpty():
+                        if source_panel.HasCapture():
+                            source_panel.ReleaseMouse()
+                        self.GraphicPanels.remove(source_panel)
+                        source_panel.Destroy()
+            elif (merge_type != graph_type and len(target_panel.Items) == 2):
+                target_panel.RemoveItem(source_item)
+            else:
+                target_panel = None
+                
+            if target_panel is not None:
+                target_panel.AddItem(source_item)
+                target_panel.GraphType = merge_type
+                size = target_panel.GetSize()
+                if merge_type == GRAPH_ORTHOGONAL:
+                    target_panel.SetCanvasSize(size.width, size.width)
+                elif source_size is not None:
+                    target_panel.SetCanvasSize(size.width, size.height + source_size.height)
+                else:
+                    target_panel.SetCanvasSize(size.width, size.height)
+                target_panel.ResetGraphics()
+                
+                self.ResetVariableNameMask()
+                self.RefreshGraphicsSizer()
+                self.ForceRefresh()
+    
+    def DeleteValue(self, source_panel, item=None):
+        source_idx = self.GetViewerIndex(source_panel)
+        if source_idx is not None:
+            
+            if item is None:
+                source_panel.Clear()
+                source_panel.Destroy()
+                self.GraphicPanels.remove(source_panel)
+                self.ResetVariableNameMask()
+                self.RefreshGraphicsSizer()
+            else:
+                source_panel.RemoveItem(item)
+                if source_panel.IsEmpty():
+                    source_panel.Destroy()
+                    self.GraphicPanels.remove(source_panel)
+                    self.ResetVariableNameMask()
+                    self.RefreshGraphicsSizer()
+            self.ForceRefresh()
+    
+    def ResetGraphicsValues(self):
+        self.Ticks = numpy.array([])
+        self.StartTick = 0
+        self.Fixed = False
+        for panel in self.GraphicPanels:
+            panel.ResetData()
+        self.ResetCursorTick()
+
+    def RefreshGraphicsWindowScrollbars(self):
+        xstart, ystart = self.GraphicsWindow.GetViewStart()
+        window_size = self.GraphicsWindow.GetClientSize()
+        vwidth, vheight = self.GraphicsSizer.GetMinSize()
+        posx = max(0, min(xstart, (vwidth - window_size[0]) / SCROLLBAR_UNIT))
+        posy = max(0, min(ystart, (vheight - window_size[1]) / SCROLLBAR_UNIT))
+        self.GraphicsWindow.Scroll(posx, posy)
+        self.GraphicsWindow.SetScrollbars(SCROLLBAR_UNIT, SCROLLBAR_UNIT, 
+                vwidth / SCROLLBAR_UNIT, vheight / SCROLLBAR_UNIT, posx, posy)
+    
+    def OnGraphicsWindowEraseBackground(self, event):
+        pass
+    
+    def OnGraphicsWindowPaint(self, event):
+        self.RefreshView()
+        event.Skip()
+    
+    def OnGraphicsWindowResize(self, event):
+        size = self.GetSize()
+        for panel in self.GraphicPanels:
+            panel_size = panel.GetSize()
+            if (isinstance(panel, DebugVariableGraphic) and 
+                panel.GraphType == GRAPH_ORTHOGONAL and 
+                panel_size.width == panel_size.height):
+                panel.SetCanvasSize(size.width, size.width)
+        self.RefreshGraphicsWindowScrollbars()
+        self.GraphicsSizer.Layout()
+        event.Skip()
+
+    def OnGraphicsWindowMouseWheel(self, event):
+        if self.VetoScrollEvent:
+            self.VetoScrollEvent = False
+        else:
+            event.Skip()