#----------------------------------------------------------------------------
# Name:         FCObjects.py
# Purpose:      Contains all the drawing objects FloatCanvas supports
#
# Author:
#
# Created:
# Version:
# Date:
# Licence:
# Tags:         phoenix-port, unittest, documented, py3-port
#----------------------------------------------------------------------------
"""
This is where FloatCanvas defines its drawings objects.
"""

import sys

import wx
import six

import numpy as N

from .Utilities import BBox
from wx.lib.floatcanvas.Utilities import Colors

mac = sys.platform.startswith("darwin")

## A global variable to hold the Pixels per inch that wxWindows thinks is in use
## This is used for scaling fonts.
## This can't be computed on module __init__, because a wx.App might not have initialized yet.
global FontScale


def ComputeFontScale():
    """
    Compute the font scale.

    A global variable to hold the scaling from pixel size to point size.
    """
    global FontScale
    dc = wx.ScreenDC()
    dc.SetFont(wx.Font(16, wx.FONTFAMILY_ROMAN, wx.FONTSTYLE_NORMAL, wx.FONTWEIGHT_NORMAL))
    E = dc.GetTextExtent("X")
    FontScale = 16/E[1]
    del dc

# why do we do this here, causes a Sphinx build crash
#ComputeFontScale()

## fixme: This should probably be re-factored into a class
_testBitmap = None

def _cycleidxs(indexcount, maxvalue, step):

    """
    Utility function used by _colorGenerator
    """
    def colormatch(color):
        """Return True if the color comes back from the bitmap identically."""
        if len(color) < 3:
            return True
        global _testBitmap
        dc = wx.MemoryDC()
        if not _testBitmap:
            _testBitmap = wx.Bitmap(1, 1)
        dc.SelectObject(_testBitmap)
        dc.SetBackground(wx.BLACK_BRUSH)
        dc.Clear()
        dc.SetPen(wx.Pen(wx.Colour(*color), 4))
        dc.DrawPoint(0,0)
        if mac: # NOTE: can the Mac not just use the DC?
            del dc # Mac can't work with bitmap when selected into a DC.
            pdata = wx.AlphaPixelData(_testBitmap)
            pacc = pdata.GetPixels()
            pacc.MoveTo(pdata, 0, 0)
            outcolor = pacc.Get()[:3]
        else:
            outcolor = dc.GetPixel(0,0)
        return outcolor == color

    if indexcount == 0:
        yield ()
    else:
        for idx in range(0, maxvalue, step):
            for tail in _cycleidxs(indexcount - 1, maxvalue, step):
                color = (idx, ) + tail
                if not colormatch(color):
                    continue
                yield color


def _colorGenerator():

    """
    Generates a series of unique colors used to do hit-tests with the Hit
    Test bitmap
    """
    return _cycleidxs(indexcount=3, maxvalue=256, step=1)


class DrawObject:
    """
    This is the base class for all the objects that can be drawn.

    One must subclass from this (and an assortment of Mixins) to create
    a new DrawObject, see for example :class:`~lib.floatcanvas.FloatCanvas.Circle`.

    """
    #This class contains a series of static dictionaries:

    #* BrushList
    #* PenList
    #* FillStyleList
    #* LineStyleList


    def __init__(self, InForeground  = False, IsVisible = True):
        """
        Default class constructor.

        :param boolean `InForeground`: Define if object should be in foreground
         or not
        :param boolean `IsVisible`: Define if object should be visible

        """
        self.InForeground = InForeground

        self._Canvas = None

        self.HitColor = None
        self.CallBackFuncs = {}

        ## these are the defaults
        self.HitAble = False
        self.HitLine = True
        self.HitFill = True
        self.MinHitLineWidth = 3
        self.HitLineWidth = 3 ## this gets re-set by the subclasses if necessary

        self.Brush = None
        self.Pen = None

        self.FillStyle = "Solid"

        self.Visible = IsVisible

    # I pre-define all these as class variables to provide an easier
    # interface, and perhaps speed things up by caching all the Pens
    # and Brushes, although that may not help, as I think wx now
    # does that on it's own. Send me a note if you know!

    BrushList = {
            ( None, "Transparent")  : wx.TRANSPARENT_BRUSH,
            ("Blue", "Solid")       : wx.BLUE_BRUSH,
            ("Green", "Solid")      : wx.GREEN_BRUSH,
            ("White", "Solid")      : wx.WHITE_BRUSH,
            ("Black", "Solid")      : wx.BLACK_BRUSH,
            ("Grey", "Solid")       : wx.GREY_BRUSH,
            ("MediumGrey", "Solid") : wx.MEDIUM_GREY_BRUSH,
            ("LightGrey", "Solid")  : wx.LIGHT_GREY_BRUSH,
            ("Cyan", "Solid")       : wx.CYAN_BRUSH,
            ("Red", "Solid")        : wx.RED_BRUSH
                    }
    PenList = {
            (None, "Transparent", 1)   : wx.TRANSPARENT_PEN,
            ("Green", "Solid", 1)      : wx.GREEN_PEN,
            ("White", "Solid", 1)      : wx.WHITE_PEN,
            ("Black", "Solid", 1)      : wx.BLACK_PEN,
            ("Grey", "Solid", 1)       : wx.GREY_PEN,
            ("MediumGrey", "Solid", 1) : wx.MEDIUM_GREY_PEN,
            ("LightGrey", "Solid", 1)  : wx.LIGHT_GREY_PEN,
            ("Cyan", "Solid", 1)       : wx.CYAN_PEN,
            ("Red", "Solid", 1)        : wx.RED_PEN
            }

    FillStyleList = {
            "Transparent"    : wx.BRUSHSTYLE_TRANSPARENT,
            "Solid"          : wx.BRUSHSTYLE_SOLID,
            "BiDiagonalHatch": wx.BRUSHSTYLE_BDIAGONAL_HATCH,
            "CrossDiagHatch" : wx.BRUSHSTYLE_CROSSDIAG_HATCH,
            "FDiagonal_Hatch": wx.BRUSHSTYLE_FDIAGONAL_HATCH,
            "CrossHatch"     : wx.BRUSHSTYLE_CROSS_HATCH,
            "HorizontalHatch": wx.BRUSHSTYLE_HORIZONTAL_HATCH,
            "VerticalHatch"  : wx.BRUSHSTYLE_VERTICAL_HATCH
            }

    LineStyleList = {
            "Solid"      : wx.PENSTYLE_SOLID,
            "Transparent": wx.PENSTYLE_TRANSPARENT,
            "Dot"        : wx.PENSTYLE_DOT,
            "LongDash"   : wx.PENSTYLE_LONG_DASH,
            "ShortDash"  : wx.PENSTYLE_SHORT_DASH,
            "DotDash"    : wx.PENSTYLE_DOT_DASH,
            }

    def Bind(self, Event, CallBackFun):
        """
        Bind an event to the DrawObject

        :param `Event`: see below for supported event types

         - EVT_FC_LEFT_DOWN
         - EVT_FC_LEFT_UP
         - EVT_FC_LEFT_DCLICK
         - EVT_FC_MIDDLE_DOWN
         - EVT_FC_MIDDLE_UP
         - EVT_FC_MIDDLE_DCLICK
         - EVT_FC_RIGHT_DOWN
         - EVT_FC_RIGHT_UP
         - EVT_FC_RIGHT_DCLICK
         - EVT_FC_ENTER_OBJECT
         - EVT_FC_LEAVE_OBJECT

        :param `CallBackFun`: the call back function for the event


        """
        ##fixme: Way too much Canvas Manipulation here!
        self.CallBackFuncs[Event] = CallBackFun
        self.HitAble = True
        self._Canvas.UseHitTest = True
        if self.InForeground and self._Canvas._ForegroundHTBitmap is None:
            self._Canvas.MakeNewForegroundHTBitmap()
        elif self._Canvas._HTBitmap is None:
            self._Canvas.MakeNewHTBitmap()
        if not self.HitColor:
            if not self._Canvas.HitColorGenerator:
                 # first call to prevent the background color from being used.
                self._Canvas.HitColorGenerator = _colorGenerator()
                if six.PY3:
                    next(self._Canvas.HitColorGenerator)
                else:
                    self._Canvas.HitColorGenerator.next()
            if six.PY3:
                self.HitColor = next(self._Canvas.HitColorGenerator)
            else:
                self.HitColor = self._Canvas.HitColorGenerator.next()
            self.SetHitPen(self.HitColor,self.HitLineWidth)
            self.SetHitBrush(self.HitColor)
        # put the object in the hit dict, indexed by it's color
        if not self._Canvas.HitDict:
            self._Canvas.MakeHitDict()
        self._Canvas.HitDict[Event][self.HitColor] = (self) # put the object in the hit dict, indexed by its color

    def UnBindAll(self):
        """
        Unbind all events

        .. note:: Currently only removes one from each list

        """
        ## fixme: this only removes one from each list, there could be more.
        ## + patch by Tim Ansel
        if self._Canvas.HitDict:
            for Event in self._Canvas.HitDict.itervalues():
                try:
                    del Event[self.HitColor]
                except KeyError:
                    pass
        self.HitAble = False


    def SetBrush(self, FillColor, FillStyle):
        """
        Set the brush for this DrawObject

        :param `FillColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
         for valid entries
        :param `FillStyle`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetFillStyle`
         for valid entries
        """
        if FillColor is None or FillStyle is None:
            self.Brush = wx.TRANSPARENT_BRUSH
            ##fixme: should I really re-set the style?
            self.FillStyle = "Transparent"
        else:
            self.Brush = self.BrushList.setdefault(
                (FillColor, FillStyle),
                wx.Brush(FillColor, self.FillStyleList[FillStyle]))
            #print("Setting Brush, BrushList length:", len(self.BrushList))

    def SetPen(self, LineColor, LineStyle, LineWidth):
        """
        Set the Pen for this DrawObject

        :param `LineColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
         for valid entries
        :param `LineStyle`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetLineStyle`
         for valid entries
        :param integer `LineWidth`: the width in pixels
        """
        if (LineColor is None) or (LineStyle is None):
            self.Pen = wx.TRANSPARENT_PEN
            self.LineStyle = 'Transparent'
        else:
            self.Pen = self.PenList.setdefault(
                (LineColor, LineStyle, LineWidth),
                wx.Pen(LineColor, LineWidth, self.LineStyleList[LineStyle]))

    def SetHitBrush(self, HitColor):
        """
        Set the brush used for hit test, do not call directly.

        :param `HitColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`

        """
        if not self.HitFill:
            self.HitBrush = wx.TRANSPARENT_BRUSH
        else:
            self.HitBrush = self.BrushList.setdefault(
                (HitColor,"solid"),
                wx.Brush(HitColor, self.FillStyleList["Solid"]))

    def SetHitPen(self, HitColor, LineWidth):
        """
        Set the pen used for hit test, do not call directly.

        :param `HitColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
        :param integer `LineWidth`: the line width in pixels

        """
        if not self.HitLine:
            self.HitPen = wx.TRANSPARENT_PEN
        else:
            self.HitPen = self.PenList.setdefault( (HitColor, "solid", self.HitLineWidth),  wx.Pen(HitColor, self.HitLineWidth, self.LineStyleList["Solid"]) )

    ## Just to make sure that they will always be there
    ##   the appropriate ones should be overridden in the subclasses
    def SetColor(self, Color):
        """
        Set the Color - this method is overridden in the subclasses

        :param `Color`: use one of the following values any valid entry from
         :class:`wx.ColourDatabase`

         - ``Green``
         - ``White``
         - ``Black``
         - ``Grey``
         - ``MediumGrey``
         - ``LightGrey``
         - ``Cyan``
         - ``Red``

        """

        pass

    def SetLineColor(self, LineColor):
        """
        Set the LineColor - this method is overridden in the subclasses

        :param `LineColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
         for valid values

        """
        pass

    def SetLineStyle(self, LineStyle):
        """
        Set the LineStyle - this method is overridden in the subclasses

        :param `LineStyle`: Use one of the following values or ``None`` :

          ===================== =============================
          Style                 Description
          ===================== =============================
          ``Solid``             Solid line
          ``Transparent``       A transparent line
          ``Dot``               Dotted line
          ``LongDash``          Dashed line (long)
          ``ShortDash``         Dashed line (short)
          ``DotDash``           Dash-dot-dash line
          ===================== =============================

        """
        pass

    def SetLineWidth(self, LineWidth):
        """
        Set the LineWidth

        :param integer `LineWidth`: sets the line width in pixel

        """
        pass

    def SetFillColor(self, FillColor):
        """
        Set the FillColor - this method is overridden in the subclasses

        :param `FillColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
         for valid values

        """
        pass

    def SetFillStyle(self, FillStyle):
        """
        Set the FillStyle - this method is overridden in the subclasses

        :param string `FillStyle`: following is a list of valid values:

          ===================== =========================================
          Style                 Description
          ===================== =========================================
          ``Transparent``       Transparent fill
          ``Solid``             Solid fill
          ``BiDiagonalHatch``   Bi Diagonal hatch fill
          ``CrossDiagHatch``    Cross Diagonal hatch fill
          ``FDiagonal_Hatch``   F Diagonal hatch fill
          ``CrossHatch``        Cross hatch fill
          ``HorizontalHatch``   Horizontal hatch fill
          ``VerticalHatch``     Vertical hatch fill
          ===================== =========================================

        """
        pass

    def PutInBackground(self):
        """Put the object in the background."""
        if self._Canvas and self.InForeground:
            self._Canvas._ForeDrawList.remove(self)
            self._Canvas._DrawList.append(self)
            self._Canvas._BackgroundDirty = True
            self.InForeground = False

    def PutInForeground(self):
        """Put the object in the foreground."""
        if self._Canvas and (not self.InForeground):
            self._Canvas._ForeDrawList.append(self)
            self._Canvas._DrawList.remove(self)
            self._Canvas._BackgroundDirty = True
            self.InForeground = True

    def Hide(self):
        """Hide the object."""
        self.Visible = False

    def Show(self):
        """Show the object."""
        self.Visible = True


class ColorOnlyMixin:
    """
    Mixin class for objects that have just one color, rather than a fill
    color and line color

    """

    def SetColor(self, Color):
        """
        Set the Color

        :param `Color`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
         for valid values

        """
        self.SetPen(Color,"Solid",1)
        self.SetBrush(Color,"Solid")

    SetFillColor = SetColor # Just to provide a consistant interface


class LineOnlyMixin:
    """
    Mixin class for objects that have just a line, rather than a fill
    color and line color

    """

    def SetLineColor(self, LineColor):
        """
        Set the LineColor

        :param `LineColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
         for valid values

        """
        self.LineColor = LineColor
        self.SetPen(LineColor,self.LineStyle,self.LineWidth)
    SetColor = SetLineColor# so that it will do something reasonable

    def SetLineStyle(self, LineStyle):
        """
        Set the LineStyle

        :param `LineStyle`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetLineStyle`
         for valid values

        """
        self.LineStyle = LineStyle
        self.SetPen(self.LineColor,LineStyle,self.LineWidth)

    def SetLineWidth(self, LineWidth):
        """
        Set the LineWidth

        :param integer `LineWidth`: line width in pixels

        """
        self.LineWidth = LineWidth
        self.SetPen(self.LineColor,self.LineStyle,LineWidth)


class LineAndFillMixin(LineOnlyMixin):
    """
    Mixin class for objects that have both a line and a fill color and
    style.

    """
    def SetFillColor(self, FillColor):
        """
        Set the FillColor

        :param `FillColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
         for valid values

        """
        self.FillColor = FillColor
        self.SetBrush(FillColor, self.FillStyle)

    def SetFillStyle(self, FillStyle):
        """
        Set the FillStyle

        :param `FillStyle`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetFillStyle`
         for valid values

        """
        self.FillStyle = FillStyle
        self.SetBrush(self.FillColor,FillStyle)

    def SetUpDraw(self, dc, WorldToPixel, ScaleWorldToPixel, HTdc):
        """
        Setup for draw

        :param `dc`: the dc to draw ???
        :param `WorldToPixel`: ???
        :param `ScaleWorldToPixel`: ???
        :param `HTdc`: ???

        """
        dc.SetPen(self.Pen)
        dc.SetBrush(self.Brush)
        if HTdc and self.HitAble:
            HTdc.SetPen(self.HitPen)
            HTdc.SetBrush(self.HitBrush)
        return ( WorldToPixel(self.XY),
                 ScaleWorldToPixel(self.WH) )


class XYObjectMixin:
    """
    This is a mixin class that provides some methods suitable for use
    with objects that have a single (x,y) coordinate pair.
    """

    def Move(self, Delta):
        """
        Moves the object by delta, where delta is a (dx, dy) pair.

        :param `Delta`: is a (dx, dy) pair ideally a `NumPy <http://www.numpy.org/>`_
         array of shape (2, )

        """
        Delta = N.asarray(Delta, N.float)
        self.XY += Delta
        self.BoundingBox += Delta

        if self._Canvas:
            self._Canvas.BoundingBoxDirty = True

    def CalcBoundingBox(self):
        """Calculate the bounding box."""
        ## This may get overwritten in some subclasses
        self.BoundingBox = BBox.asBBox((self.XY, self.XY))

    def SetPoint(self, xy):
        xy = N.array(xy, N.float)
        xy.shape = (2,)

        self.XY = xy
        self.CalcBoundingBox()

        if self._Canvas:
            self._Canvas.BoundingBoxDirty = True

class PointsObjectMixin:
    """
    A mixin class that provides some methods suitable for use
    with objects that have a set of (x, y) coordinate pairs.

    """

    def Move(self, Delta):
        """
        Moves the object by delta, where delta is a (dx, dy) pair.

        :param `Delta`: is a (dx, dy) pair ideally a `NumPy <http://www.numpy.org/>`_
         array of shape (2, )

        """
        Delta = N.asarray(Delta, N.float)
        Delta.shape = (2,)
        self.Points += Delta
        self.BoundingBox += Delta
        if self._Canvas:
            self._Canvas.BoundingBoxDirty = True

    def CalcBoundingBox(self):
        """Calculate the bounding box."""
        self.BoundingBox = BBox.fromPoints(self.Points)
        if self._Canvas:
            self._Canvas.BoundingBoxDirty = True

    def SetPoints(self, Points, copy=True):
        """
        Sets the coordinates of the points of the object to Points (NX2 array).

        :param `Points`: takes a 2-tuple, or a (2,)
         `NumPy <http://www.numpy.org/>`_ array of point coordinates
        :param boolean `copy`: By default, a copy is made, if copy is set to
         ``False``, a reference is used, if Points is a NumPy array of Floats.
         This allows you to change some or all of the points without making
         any copies.

        For example::

            Points = Object.Points
            # shifts the points 5 in the x dir, and 10 in the y dir.
            Points += (5, 10)
            # Sets the points to the same array as it was
            Object.SetPoints(Points, False)

        """
        if copy:
            self.Points = N.array(Points, N.float)
            self.Points.shape = (-1, 2) # Make sure it is a NX2 array, even if there is only one point
        else:
            self.Points = N.asarray(Points, N.float)
        self.CalcBoundingBox()


class Polygon(PointsObjectMixin, LineAndFillMixin, DrawObject):
    """
    Draws a polygon

    Points is a list of 2-tuples, or a NX2 NumPy array of
    point coordinates.  so that Points[N][0] is the x-coordinate of
    point N and Points[N][1] is the y-coordinate or Points[N,0] is the
    x-coordinate of point N and Points[N,1] is the y-coordinate for
    arrays.

    """
    def __init__(self,
                 Points,
                 LineColor = "Black",
                 LineStyle = "Solid",
                 LineWidth    = 1,
                 FillColor    = None,
                 FillStyle    = "Solid",
                 InForeground = False):
        """
        Default class constructor.

        :param `Points`: start point, takes a 2-tuple, or a (2,)
         `NumPy <http://www.numpy.org/>`_ array of point coordinates
        :param `LineColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
        :param `LineStyle`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetLineStyle`
        :param `LineWidth`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetLineWidth`
        :param `FillColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
        :param `FillStyle`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetFillStyle`
        :param boolean `InForeground`: should object be in foreground

        """
        DrawObject.__init__(self, InForeground)
        self.Points = N.array(Points ,N.float) # this DOES need to make a copy
        self.CalcBoundingBox()

        self.LineColor = LineColor
        self.LineStyle = LineStyle
        self.LineWidth = LineWidth
        self.FillColor = FillColor
        self.FillStyle = FillStyle

        self.HitLineWidth = max(LineWidth,self.MinHitLineWidth)

        self.SetPen(LineColor,LineStyle,LineWidth)
        self.SetBrush(FillColor,FillStyle)

    def _Draw(self, dc , WorldToPixel, ScaleWorldToPixel = None, HTdc=None):
        Points = WorldToPixel(self.Points)#.tolist()
        dc.SetPen(self.Pen)
        dc.SetBrush(self.Brush)
        dc.DrawPolygon(Points)
        if HTdc and self.HitAble:
            HTdc.SetPen(self.HitPen)
            HTdc.SetBrush(self.HitBrush)
            HTdc.DrawPolygon(Points)

class Line(PointsObjectMixin, LineOnlyMixin, DrawObject):
    """
    Draws a line

    It will draw a straight line if there are two points, and a polyline
    if there are more than two.

    """
    def __init__(self, Points,
                 LineColor = "Black",
                 LineStyle = "Solid",
                 LineWidth    = 1,
                 InForeground = False):
        """
        Default class constructor.

        :param `Points`: takes a 2-tuple, or a (2,)
         `NumPy <http://www.numpy.org/>`_ array of point coordinates
        :param `LineColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
        :param `LineStyle`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetLineStyle`
        :param `LineWidth`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetLineWidth`
        :param boolean `InForeground`: should object be in foreground

        """
        DrawObject.__init__(self, InForeground)


        self.Points = N.array(Points,N.float)
        self.CalcBoundingBox()

        self.LineColor = LineColor
        self.LineStyle = LineStyle
        self.LineWidth = LineWidth

        self.SetPen(LineColor,LineStyle,LineWidth)

        self.HitLineWidth = max(LineWidth,self.MinHitLineWidth)


    def _Draw(self, dc , WorldToPixel, ScaleWorldToPixel, HTdc=None):
        Points = WorldToPixel(self.Points)
        dc.SetPen(self.Pen)
        dc.DrawLines(Points)
        if HTdc and self.HitAble:
            HTdc.SetPen(self.HitPen)
            HTdc.DrawLines(Points)

class Spline(Line):
    """Draws a spline"""
    def __init__(self, *args, **kwargs):
        """
        Default class constructor.

        see :class:`~lib.floatcanvas.FloatCanvas.Line`

        """
        Line.__init__(self, *args, **kwargs)

    def _Draw(self, dc , WorldToPixel, ScaleWorldToPixel, HTdc=None):
        Points = WorldToPixel(self.Points)
        dc.SetPen(self.Pen)
        dc.DrawSpline(Points)
        if HTdc and self.HitAble:
            HTdc.SetPen(self.HitPen)
            HTdc.DrawSpline(Points)


class Arrow(XYObjectMixin, LineOnlyMixin, DrawObject):
    """
    Draws an arrow

    It will draw an arrow , starting at the point ``XY`` points at an angle
    defined by ``Direction``.

    """
    def __init__(self,
                 XY,
                 Length,
                 Direction,
                 LineColor = "Black",
                 LineStyle = "Solid",
                 LineWidth    = 2,
                 ArrowHeadSize = 8,
                 ArrowHeadAngle = 30,
                 InForeground = False):
        """
        Default class constructor.

        :param `XY`: the (x, y) coordinate of the starting point, or a 2-tuple,
         or a (2,) `NumPy <http://www.numpy.org/>`_ array
        :param integer `Length`: length of arrow in pixels
        :param integer `Direction`: angle of arrow in degrees, zero is straight
          up `+` angle is to the right
        :param `LineColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
        :param `LineStyle`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetLineStyle`
        :param `LineWidth`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetLineWidth`
        :param `ArrowHeadSize`: size of arrow head in pixels
        :param `ArrowHeadAngle`: angle of arrow head in degrees
        :param boolean `InForeground`: should object be in foreground

        """

        DrawObject.__init__(self, InForeground)

        self.XY = N.array(XY, N.float)
        self.XY.shape = (2,) # Make sure it is a length 2 vector
        self.Length = Length
        self.Direction = float(Direction)
        self.ArrowHeadSize = ArrowHeadSize
        self.ArrowHeadAngle = float(ArrowHeadAngle)

        self.CalcArrowPoints()
        self.CalcBoundingBox()

        self.LineColor = LineColor
        self.LineStyle = LineStyle
        self.LineWidth = LineWidth

        self.SetPen(LineColor,LineStyle,LineWidth)

        ##fixme: How should the HitTest be drawn?
        self.HitLineWidth = max(LineWidth,self.MinHitLineWidth)

    def SetDirection(self, Direction):
        """
        Set the direction

        :param integer `Direction`: angle of arrow in degrees, zero is straight
          up `+` angle is to the right

        """
        self.Direction = float(Direction)
        self.CalcArrowPoints()

    def SetLength(self, Length):
        """
        Set the length

        :param integer `Length`: length of arrow in pixels

        """
        self.Length = Length
        self.CalcArrowPoints()

    def SetLengthDirection(self, Length, Direction):
        """
        Set the lenght and direction

        :param integer `Length`: length of arrow in pixels
        :param integer `Direction`: angle of arrow in degrees, zero is straight
          up `+` angle is to the right

        """
        self.Direction = float(Direction)
        self.Length = Length
        self.CalcArrowPoints()

##    def CalcArrowPoints(self):
##        L = self.Length
##        S = self.ArrowHeadSize
##        phi = self.ArrowHeadAngle * N.pi / 360
##        theta = (self.Direction-90.0) * N.pi / 180
##        ArrowPoints = N.array( ( (0, L, L - S*N.cos(phi),L, L - S*N.cos(phi) ),
##                               (0, 0, S*N.sin(phi),    0, -S*N.sin(phi)    ) ),
##                             N.float )
##        RotationMatrix = N.array( ( ( N.cos(theta), -N.sin(theta) ),
##                                  ( N.sin(theta), N.cos(theta) ) ),
##                                N.float
##                                )
##        ArrowPoints = N.matrixmultiply(RotationMatrix, ArrowPoints)
##        self.ArrowPoints = N.transpose(ArrowPoints)

    def CalcArrowPoints(self):
        """Calculate the arrow points."""
        L = self.Length
        S = self.ArrowHeadSize
        phi = self.ArrowHeadAngle * N.pi / 360
        theta = (270 - self.Direction) * N.pi / 180
        AP = N.array( ( (0,0),
                        (0,0),
                        (N.cos(theta - phi), -N.sin(theta - phi) ),
                        (0,0),
                        (N.cos(theta + phi), -N.sin(theta + phi) ),
                        ), N.float )
        AP *= S
        shift = (-L*N.cos(theta), L*N.sin(theta) )
        AP[1:,:] += shift
        self.ArrowPoints = AP

    def _Draw(self, dc , WorldToPixel, ScaleWorldToPixel, HTdc=None):
        dc.SetPen(self.Pen)
        xy = WorldToPixel(self.XY)
        ArrowPoints = xy + self.ArrowPoints
        dc.DrawLines(ArrowPoints)
        if HTdc and self.HitAble:
            HTdc.SetPen(self.HitPen)
            HTdc.DrawLines(ArrowPoints)


class ArrowLine(PointsObjectMixin, LineOnlyMixin, DrawObject):
    """
    Draws an arrow line.

    It will draw a set of arrows from point to point.

    It takes a list of 2-tuples, or a NX2 NumPy Float array of point coordinates.

    """

    def __init__(self,
                 Points,
                 LineColor = "Black",
                 LineStyle = "Solid",
                 LineWidth    = 1,
                 ArrowHeadSize = 8,
                 ArrowHeadAngle = 30,
                 InForeground = False):
        """
        Default class constructor.

        :param `Points`: takes a 2-tuple, or a (2,)
         `NumPy <http://www.numpy.org/>`_ array of point coordinates
        :param `LineColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
        :param `LineStyle`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetLineStyle`
        :param `LineWidth`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetLineWidth`
        :param `ArrowHeadSize`: size of arrow head in pixels
        :param `ArrowHeadAngle`: angle of arrow head in degrees
        :param boolean `InForeground`: should object be in foreground

        """

        DrawObject.__init__(self, InForeground)

        self.Points = N.asarray(Points,N.float)
        self.Points.shape = (-1,2) # Make sure it is a NX2 array, even if there is only one point
        self.ArrowHeadSize = ArrowHeadSize
        self.ArrowHeadAngle = float(ArrowHeadAngle)

        self.CalcArrowPoints()
        self.CalcBoundingBox()

        self.LineColor = LineColor
        self.LineStyle = LineStyle
        self.LineWidth = LineWidth

        self.SetPen(LineColor,LineStyle,LineWidth)

        self.HitLineWidth = max(LineWidth,self.MinHitLineWidth)

    def CalcArrowPoints(self):
        """Calculate the arrow points."""
        S = self.ArrowHeadSize
        phi = self.ArrowHeadAngle * N.pi / 360
        Points = self.Points
        n = Points.shape[0]
        self.ArrowPoints = N.zeros((n-1, 3, 2), N.float)
        for i in range(n-1):
            dx, dy = self.Points[i] - self.Points[i+1]
            theta = N.arctan2(dy, dx)
            AP = N.array( (
                            (N.cos(theta - phi), -N.sin(theta-phi)),
                            (0,0),
                            (N.cos(theta + phi), -N.sin(theta + phi))
                            ),
                          N.float )
            self.ArrowPoints[i,:,:] = AP
        self.ArrowPoints *= S

    def _Draw(self, dc , WorldToPixel, ScaleWorldToPixel, HTdc=None):
        Points = WorldToPixel(self.Points)
        ArrowPoints = Points[1:,N.newaxis,:] + self.ArrowPoints
        dc.SetPen(self.Pen)
        dc.DrawLines(Points)
        for arrow in ArrowPoints:
                dc.DrawLines(arrow)
        if HTdc and self.HitAble:
            HTdc.SetPen(self.HitPen)
            HTdc.DrawLines(Points)
            for arrow in ArrowPoints:
                HTdc.DrawLines(arrow)


class PointSet(PointsObjectMixin, ColorOnlyMixin, DrawObject):
    """
    Draws a set of points

    If Points is a sequence of tuples: Points[N][0] is the x-coordinate of
    point N and Points[N][1] is the y-coordinate.

    If Points is a NumPy array: Points[N,0] is the x-coordinate of point
    N and Points[N,1] is the y-coordinate for arrays.

    Each point will be drawn the same color and Diameter. The Diameter
    is in screen pixels, not world coordinates.

    The hit-test code does not distingish between the points, you will
    only know that one of the points got hit, not which one. You can use
    PointSet.FindClosestPoint(WorldPoint) to find out which one

    In the case of points, the HitLineWidth is used as diameter.

    """
    def __init__(self, Points, Color="Black", Diameter=1, InForeground=False):
        """
        Default class constructor.

        :param `Points`: takes a 2-tuple, or a (2,)
         `NumPy <http://www.numpy.org/>`_ array of point coordinates
        :param `Color`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
        :param integer `Diameter`: the points diameter
        :param boolean `InForeground`: should object be in foreground

        """
        DrawObject.__init__(self, InForeground)

        self.Points = N.array(Points,N.float)
        self.Points.shape = (-1,2) # Make sure it is a NX2 array, even if there is only one point
        self.CalcBoundingBox()
        self.Diameter = Diameter

        self.HitLineWidth = min(self.MinHitLineWidth, Diameter)
        self.SetColor(Color)

    def SetDiameter(self, Diameter):
        """
        Sets the diameter

        :param integer `Diameter`: the points diameter

        """
        self.Diameter = Diameter

    def FindClosestPoint(self, XY):
        """
        Returns the index of the closest point to the point, XY, given
        in World coordinates. It's essentially random which you get if
        there are more than one that are the same.

        This can be used to figure out which point got hit in a mouse
        binding callback, for instance. It's a lot faster that using a
        lot of separate points.

        :param `XY`: the (x,y) coordinates of the point to look for, it takes a
         2-tuple or (2,) numpy array in World coordinates

        """
        d = self.Points - XY
        return N.argmin(N.hypot(d[:,0],d[:,1]))


    def DrawD2(self, dc, Points):
        # A Little optimization for a diameter2 - point
        dc.DrawPointList(Points)
        dc.DrawPointList(Points + (1,0))
        dc.DrawPointList(Points + (0,1))
        dc.DrawPointList(Points + (1,1))

    def _Draw(self, dc , WorldToPixel, ScaleWorldToPixel, HTdc=None):
        dc.SetPen(self.Pen)
        Points = WorldToPixel(self.Points)
        if self.Diameter <= 1:
            dc.DrawPointList(Points)
        elif self.Diameter <= 2:
            self.DrawD2(dc, Points)
        else:
            dc.SetBrush(self.Brush)
            radius = int(round(self.Diameter/2))
            ##fixme: I really should add a DrawCircleList to wxPython
            if len(Points) > 100:
                xy = Points
                xywh = N.concatenate((xy-radius, N.ones(xy.shape) * self.Diameter ), 1 )
                dc.DrawEllipseList(xywh)
            else:
                for xy in Points:
                    dc.DrawCircle(xy[0],xy[1], radius)
        if HTdc and self.HitAble:
            HTdc.SetPen(self.HitPen)
            HTdc.SetBrush(self.HitBrush)
            if self.Diameter <= 1:
                HTdc.DrawPointList(Points)
            elif self.Diameter <= 2:
                self.DrawD2(HTdc, Points)
            else:
                if len(Points) > 100:
                    xy = Points
                    xywh = N.concatenate((xy-radius, N.ones(xy.shape) * self.Diameter ), 1 )
                    HTdc.DrawEllipseList(xywh)
                else:
                    for xy in Points:
                        HTdc.DrawCircle(xy[0],xy[1], radius)

class Point(XYObjectMixin, ColorOnlyMixin, DrawObject):
    """
    A point DrawObject

    .. note::

       The Bounding box is just the point, and doesn't include the Diameter.

       The HitLineWidth is used as diameter for the Hit Test.

    """
    def __init__(self, XY, Color="Black", Diameter=1, InForeground=False):
        """
        Default class constructor.

        :param `XY`: the (x, y) coordinate of the center of the point, or a
         2-tuple, or a (2,) `NumPy <http://www.numpy.org/>`_ array
        :param `Color`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
        :param integer `Diameter`: in screen points
        :param `InForeground`: define if object is in foreground

        """

        DrawObject.__init__(self, InForeground)

        self.XY = N.array(XY, N.float)
        self.XY.shape = (2,) # Make sure it is a length 2 vector
        self.CalcBoundingBox()
        self.SetColor(Color)
        self.Diameter = Diameter

        self.HitLineWidth = self.MinHitLineWidth

    def SetDiameter(self, Diameter):
        """
        Set the diameter of the object.

        :param integer `Diameter`: in screen points

        """
        self.Diameter = Diameter

    def _Draw(self, dc, WorldToPixel, ScaleWorldToPixel, HTdc=None):
        dc.SetPen(self.Pen)
        xy = WorldToPixel(self.XY)
        if self.Diameter <= 1:
            dc.DrawPoint(xy[0], xy[1])
        else:
            dc.SetBrush(self.Brush)
            radius = int(round(self.Diameter/2))
            dc.DrawCircle(xy[0],xy[1], radius)
        if HTdc and self.HitAble:
            HTdc.SetPen(self.HitPen)
            if self.Diameter <= 1:
                HTdc.DrawPoint(xy[0], xy[1])
            else:
                HTdc.SetBrush(self.HitBrush)
                HTdc.DrawCircle(xy[0],xy[1], radius)

class SquarePoint(XYObjectMixin, ColorOnlyMixin, DrawObject):
    """
    Draws a square point

    The Size is in screen points, not world coordinates, so the
    Bounding box is just the point, and doesn't include the Size.

    The HitLineWidth is used as diameter for the  Hit Test.

    """
    def __init__(self, Point, Color="Black", Size=4, InForeground=False):
        """
        Default class constructor.

        :param `Point`: takes a 2-tuple, or a (2,)
         `NumPy <http://www.numpy.org/>`_ array of point coordinates
        :param `Color`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
        :param integer `Size`: the size of the square point
        :param boolean `InForeground`: should object be in foreground

        """
        DrawObject.__init__(self, InForeground)

        self.XY = N.array(Point, N.float)
        self.XY.shape = (2,) # Make sure it is a length 2 vector
        self.CalcBoundingBox()
        self.SetColor(Color)
        self.Size = Size

        self.HitLineWidth = self.MinHitLineWidth

    def SetSize(self, Size):
        """
        Sets the size

        :param integer `Size`: the size of the square point

        """
        self.Size = Size

    def _Draw(self, dc , WorldToPixel, ScaleWorldToPixel, HTdc=None):
        Size = self.Size
        dc.SetPen(self.Pen)
        xc,yc = WorldToPixel(self.XY)

        if self.Size <= 1:
            dc.DrawPoint(xc, yc)
        else:
            x = xc - Size/2.0
            y = yc - Size/2.0
            dc.SetBrush(self.Brush)
            dc.DrawRectangle(x, y, Size, Size)
        if HTdc and self.HitAble:
            HTdc.SetPen(self.HitPen)
            if self.Size <= 1:
                HTdc.DrawPoint(xc, xc)
            else:
                HTdc.SetBrush(self.HitBrush)
                HTdc.DrawRectangle(x, y, Size, Size)

class RectEllipse(XYObjectMixin, LineAndFillMixin, DrawObject):
    """A RectEllipse draw object."""
    def __init__(self, XY, WH,
                 LineColor = "Black",
                 LineStyle = "Solid",
                 LineWidth    = 1,
                 FillColor    = None,
                 FillStyle    = "Solid",
                 InForeground = False):
        """
        Default class constructor.

        :param `XY`: the (x, y) coordinate of the corner of RectEllipse, or a 2-tuple,
         or a (2,) `NumPy <http://www.numpy.org/>`_ array
        :param `WH`: a tuple with the Width and Height for the object
        :param `LineColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
        :param `LineStyle`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetLineStyle`
        :param `LineWidth`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetLineWidth`
        :param `FillColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
        :param `FillStyle`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetFillStyle`
        :param `InForeground`: put object in foreground

        """

        DrawObject.__init__(self,InForeground)

        self.SetShape(XY, WH)
        self.LineColor = LineColor
        self.LineStyle = LineStyle
        self.LineWidth = LineWidth
        self.FillColor = FillColor
        self.FillStyle = FillStyle

        self.HitLineWidth = max(LineWidth,self.MinHitLineWidth)

        # these define the behaviour when zooming makes the objects really small.
        self.MinSize = 1
        self.DisappearWhenSmall = True

        self.SetPen(LineColor,LineStyle,LineWidth)
        self.SetBrush(FillColor,FillStyle)

    def SetShape(self, XY, WH):
        """
        Set the shape of the object.

        :param `XY`: takes a 2-tuple, or a (2,) `NumPy <http://www.numpy.org/>`_
         array of point coordinates
        :param `WH`: a tuple with the Width and Height for the object

        """
        self.XY = N.array( XY, N.float)
        self.XY.shape = (2,)
        self.WH = N.array( WH, N.float)
        self.WH.shape = (2,)
        self.CalcBoundingBox()

    def CalcBoundingBox(self):
        """Calculate the bounding box."""
        # you need this in case Width or Height are negative
        corners = N.array((self.XY, (self.XY + self.WH) ), N.float)
        self.BoundingBox = BBox.fromPoints(corners)
        if self._Canvas:
            self._Canvas.BoundingBoxDirty = True


class Rectangle(RectEllipse):
    """Draws a rectangle see :class:`~lib.floatcanvas.FloatCanvas.RectEllipse`"""
    def _Draw(self, dc , WorldToPixel, ScaleWorldToPixel, HTdc=None):
        ( XY, WH ) = self.SetUpDraw(dc,
                                    WorldToPixel,
                                    ScaleWorldToPixel,
                                    HTdc)
        WH[N.abs(WH) < self.MinSize] = self.MinSize
        if not( self.DisappearWhenSmall and N.abs(WH).min() <=  self.MinSize) : # don't try to draw it too tiny
            dc.DrawRectangle(XY, WH)
            if HTdc and self.HitAble:
                HTdc.DrawRectangle(XY, WH)


class Ellipse(RectEllipse):
    """Draws an ellipse see :class:`~lib.floatcanvas.FloatCanvas.RectEllipse`"""
    def _Draw(self, dc , WorldToPixel, ScaleWorldToPixel, HTdc=None):
        ( XY, WH ) = self.SetUpDraw(dc,
                                    WorldToPixel,
                                    ScaleWorldToPixel,
                                    HTdc)
        WH[N.abs(WH) < self.MinSize] = self.MinSize
        if not( self.DisappearWhenSmall and N.abs(WH).min() <=  self.MinSize) : # don't try to draw it too tiny
            dc.DrawEllipse(XY, WH)
            if HTdc and self.HitAble:
                HTdc.DrawEllipse(XY, WH)

class Circle(XYObjectMixin, LineAndFillMixin, DrawObject):
    """Draws a circle"""
    def __init__(self, XY, Diameter,
                 LineColor = "Black",
                 LineStyle = "Solid",
                 LineWidth    = 1,
                 FillColor    = None,
                 FillStyle    = "Solid",
                 InForeground = False):
        """
        Default class constructor.

        :param `XY`: the (x, y) coordinate of the center of the circle, or a 2-tuple,
         or a (2,) `NumPy <http://www.numpy.org/>`_ array
        :param integer `Diameter`: the diameter for the object
        :param `LineColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
        :param `LineStyle`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetLineStyle`
        :param `LineWidth`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetLineWidth`
        :param `FillColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
        :param `FillStyle`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetFillStyle`
        :param boolean `InForeground`: should object be in foreground

        """
        DrawObject.__init__(self, InForeground)

        self.XY = N.array(XY, N.float)
        self.WH = N.array((Diameter/2, Diameter/2), N.float) # just to keep it compatible with others
        self.CalcBoundingBox()

        self.LineColor = LineColor
        self.LineStyle = LineStyle
        self.LineWidth = LineWidth
        self.FillColor = FillColor
        self.FillStyle = FillStyle

        self.HitLineWidth = max(LineWidth,self.MinHitLineWidth)

        # these define the behaviour when zooming makes the objects really small.
        self.MinSize = 1
        self.DisappearWhenSmall = True

        self.SetPen(LineColor,LineStyle,LineWidth)
        self.SetBrush(FillColor,FillStyle)

    def SetDiameter(self, Diameter):
        """
        Set the diameter of the object

        :param integer `Diameter`: the diameter for the object

        """
        self.WH = N.array((Diameter/2, Diameter/2), N.float) # just to keep it compatible with others

    def CalcBoundingBox(self):
        """Calculate the bounding box of the object."""
        # you need this in case Width or Height are negative
        self.BoundingBox = BBox.fromPoints( (self.XY+self.WH, self.XY-self.WH) )
        if self._Canvas:
            self._Canvas.BoundingBoxDirty = True

    def _Draw(self, dc , WorldToPixel, ScaleWorldToPixel, HTdc=None):
        ( XY, WH ) = self.SetUpDraw(dc,
                                    WorldToPixel,
                                    ScaleWorldToPixel,
                                    HTdc)

        WH[N.abs(WH) < self.MinSize] = self.MinSize
        if not( self.DisappearWhenSmall and N.abs(WH).min() <=  self.MinSize) : # don't try to draw it too tiny
            dc.DrawCircle(XY, WH[0])
            if HTdc and self.HitAble:
                HTdc.DrawCircle(XY, WH[0])


class TextObjectMixin(XYObjectMixin):
    """
    A mix in class that holds attributes and methods that are needed by
    the Text objects

    """

    ## I'm caching fonts, because on GTK, getting a new font can take a
    ## while. However, it gets cleared after every full draw as hanging
    ## on to a bunch of large fonts takes a massive amount of memory.

    FontList = {}

    LayoutFontSize = 16 # font size used for calculating layout

    def SetFont(self, Size, Family, Style, Weight, Underlined, FaceName):
        self.Font = self.FontList.setdefault( (Size,
                                               Family,
                                               Style,
                                               Weight,
                                               Underlined,
                                               FaceName),
                                               #wx.FontFromPixelSize((0.45*Size,Size), # this seemed to give a decent height/width ratio on Windows
                                               wx.Font(Size,
                                                       Family,
                                                       Style,
                                                       Weight,
                                                       Underlined,
                                                       FaceName) )

    def SetColor(self, Color):
        self.Color = Color

    def SetBackgroundColor(self, BackgroundColor):
        self.BackgroundColor = BackgroundColor

    def SetText(self, String):
        """
        Re-sets the text displayed by the object

        In the case of the ScaledTextBox, it will re-do the layout as appropriate

        Note: only tested with the ScaledTextBox

        """

        self.String = String
        self.LayoutText()

    def LayoutText(self):
        """
        A dummy method to re-do the layout of the text.

        A derived object needs to override this if required.

        """
        pass

    ## store the function that shift the coords for drawing text. The
    ## "c" parameter is the correction for world coordinates, rather
    ## than pixel coords as the y axis is reversed
    ## pad is the extra space around the text
    ## if world = 1, the vertical shift is done in y-up coordinates
    ShiftFunDict = {'tl': lambda x, y, w, h, world=0, pad=0: (x + pad,     y + pad - 2*world*pad),
                    'tc': lambda x, y, w, h, world=0, pad=0: (x - w/2,     y + pad - 2*world*pad),
                    'tr': lambda x, y, w, h, world=0, pad=0: (x - w - pad, y + pad - 2*world*pad),
                    'cl': lambda x, y, w, h, world=0, pad=0: (x + pad,     y - h/2 + world*h),
                    'cc': lambda x, y, w, h, world=0, pad=0: (x - w/2,     y - h/2 + world*h),
                    'cr': lambda x, y, w, h, world=0, pad=0: (x - w - pad, y - h/2 + world*h),
                    'bl': lambda x, y, w, h, world=0, pad=0: (x + pad,     y - h + 2*world*h - pad + world*2*pad) ,
                    'bc': lambda x, y, w, h, world=0, pad=0: (x - w/2,     y - h + 2*world*h - pad + world*2*pad) ,
                    'br': lambda x, y, w, h, world=0, pad=0: (x - w - pad, y - h + 2*world*h - pad + world*2*pad)}

class Text(TextObjectMixin, DrawObject):
    """
    Draws a text object

    The size is fixed, and does not scale with the drawing.

    The hit-test is done on the entire text extent

    """

    def __init__(self, String, xy,
                 Size =  14,
                 Color = "Black",
                 BackgroundColor = None,
                 Family = wx.FONTFAMILY_MODERN,
                 Style = wx.FONTSTYLE_NORMAL,
                 Weight = wx.FONTWEIGHT_NORMAL,
                 Underlined = False,
                 Position = 'tl',
                 InForeground = False,
                 Font = None):
        """
        Default class constructor.

        :param string `string`: the text to draw
        :param `XY`: the (x, y) coordinate of the corner of the text, or a 2-tuple,
         or a (2,) `NumPy <http://www.numpy.org/>`_ array
        :param `Size`: the font size
        :param `Color`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
        :param `BackgroundColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
        :param wx.FontFamily `Family`: a valid :ref:`wx.FontFamily`
        :param wx.FontStyle `Style`: a valid :ref:`wx.FontStyle`
        :param wx.FontWeight `Weight`: a valid :ref:`wx.FontWeight`
        :param boolean `Underlined`: underline the text
        :param string `Position`: a two character string indicating where in
         relation to the coordinates the box should be oriented
        :param boolean `InForeground`: should object be in foreground
        :param wx.Font `Font`: alternatively you can define :ref:`wx.Font` and the
         above will be ignored.

         ============== ==========================
         1st character  Meaning
         ============== ==========================
         ``t``          top
         ``c``          center
         ``b``          bottom
         ============== ==========================

         ============== ==========================
         2nd character  Meaning
         ============== ==========================
         ``l``          left
         ``c``          center
         ``r``          right
         ============== ==========================

        :param wx.Font `Font`: a valid :class:`wx.Font`
        :param boolean `InForeground`: should object be in foreground

        """
        DrawObject.__init__(self,InForeground)

        self.String = String
        # Input size in in Pixels, compute points size from FontScaleinfo.
        # fixme: for printing, we'll have to do something a little different
        self.Size = Size * FontScale

        self.Color = Color
        self.BackgroundColor = BackgroundColor

        if not Font:
            FaceName = ''
        else:
            FaceName           =  Font.GetFaceName()
            Family             =  Font.GetFamily()
            Size               =  Font.GetPointSize()
            Style              =  Font.GetStyle()
            Underlined         =  Font.GetUnderlined()
            Weight             =  Font.GetWeight()
        self.SetFont(Size, Family, Style, Weight, Underlined, FaceName)

        self.BoundingBox = BBox.asBBox((xy, xy))

        self.XY = N.asarray(xy)
        self.XY.shape = (2,)

        (self.TextWidth, self.TextHeight) = (None, None)
        self.ShiftFun = self.ShiftFunDict[Position]

    def _Draw(self, dc , WorldToPixel, ScaleWorldToPixel, HTdc=None):
        XY = WorldToPixel(self.XY)
        dc.SetFont(self.Font)
        dc.SetTextForeground(self.Color)
        if self.BackgroundColor:
            dc.SetBackgroundMode(wx.SOLID)
            dc.SetTextBackground(self.BackgroundColor)
        else:
            dc.SetBackgroundMode(wx.TRANSPARENT)
        if self.TextWidth is None or self.TextHeight is None:
            (self.TextWidth, self.TextHeight) = dc.GetTextExtent(self.String)
        XY = self.ShiftFun(XY[0], XY[1], self.TextWidth, self.TextHeight)
        dc.DrawText(self.String, XY)
        if HTdc and self.HitAble:
            HTdc.SetPen(self.HitPen)
            HTdc.SetBrush(self.HitBrush)
            HTdc.DrawRectangle(XY, (self.TextWidth, self.TextHeight) )

class ScaledText(TextObjectMixin, DrawObject):
    """
    ##fixme: this can be depricated and jsut use ScaledTextBox with different defaults.

    This class creates a text object that is scaled when zoomed.  It is
    placed at the coordinates, x,y. the "Position" argument is a two
    charactor string, indicating where in relation to the coordinates
    the string should be oriented.

    The first letter is: t, c, or b, for top, center and bottom The
    second letter is: l, c, or r, for left, center and right The
    position refers to the position relative to the text itself. It
    defaults to "tl" (top left).

    Size is the size of the font in world coordinates.

    * Family: Font family, a generic way of referring to fonts without
      specifying actual facename. One of:

            * wx.FONTFAMILY_DEFAULT:  Chooses a default font.
            * wx.FONTFAMILY_DECORATIVE: A decorative font.
            * wx.FONTFAMILY_ROMAN: A formal, serif font.
            * wx.FONTFAMILY_SCRIPT: A handwriting font.
            * wx.FONTFAMILY_SWISS: A sans-serif font.
            * wx.FONTFAMILY_MODERN: A fixed pitch font.

      .. note:: these are only as good as the wxWindows defaults, which aren't so good.

    * Style: One of wx.FONTSTYLE_NORMAL, wx.FONTSTYLE_SLANT and wx.FONTSTYLE_ITALIC.
    * Weight: One of wx.FONTWEIGHT_NORMAL, wx.FONTWEIGHT_LIGHT and wx.FONTWEIGHT_BOLD.
    * Underlined: The value can be True or False. At present this may have an an
      effect on Windows only.


    Alternatively, you can set the kw arg: Font, to a wx.Font, and the
    above will be ignored. The size of the font you specify will be
    ignored, but the rest of its attributes will be preserved.

    The size will scale as the drawing is zoomed.

    Bugs/Limitations:

    As fonts are scaled, the do end up a little different, so you don't
    get exactly the same picture as you scale up and doen, but it's
    pretty darn close.

    On wxGTK1 on my Linux system, at least, using a font of over about
    3000 pts. brings the system to a halt. It's the Font Server using
    huge amounts of memory. My work around is to max the font size to
    3000 points, so it won't scale past there. GTK2 uses smarter font
    drawing, so that may not be an issue in future versions, so feel
    free to test. Another smarter way to do it would be to set a global
    zoom limit at that point.

    The hit-test is done on the entire text extent. This could be made
    optional, but I haven't gotten around to it.

    """

    def __init__(self,
                 String,
                 XY,
                 Size,
                 Color = "Black",
                 BackgroundColor = None,
                 Family = wx.FONTFAMILY_MODERN,
                 Style = wx.FONTSTYLE_NORMAL,
                 Weight = wx.FONTWEIGHT_NORMAL,
                 Underlined = False,
                 Position = 'tl',
                 Font = None,
                 InForeground = False):

        DrawObject.__init__(self,InForeground)

        self.String = String
        self.XY = N.array( XY, N.float)
        self.XY.shape = (2,)
        self.Size = Size
        self.Color = Color
        self.BackgroundColor = BackgroundColor
        self.Family = Family
        self.Style = Style
        self.Weight = Weight
        self.Underlined = Underlined
        if not Font:
            self.FaceName = ''
        else:
            self.FaceName           =  Font.GetFaceName()
            self.Family             =  Font.GetFamily()
            self.Style              =  Font.GetStyle()
            self.Underlined         =  Font.GetUnderlined()
            self.Weight             =  Font.GetWeight()

        # Experimental max font size value on wxGTK2: this works OK on
        # my system. If it's a lot  larger, there is a crash, with the
        # message:
        #
        # The application 'FloatCanvasDemo.py' lost its
        # connection to the display :0.0; most likely the X server was
        # shut down or you killed/destroyed the application.
        #
        # Windows and OS-X seem to be better behaved in this regard.
        # They may not draw it, but they don't crash either!
        self.MaxFontSize = 1000
        self.MinFontSize = 1 # this can be changed to set a minimum size
        self.DisappearWhenSmall = True
        self.ShiftFun = self.ShiftFunDict[Position]

        self.CalcBoundingBox()

    def LayoutText(self):
        # This will be called when the text is re-set
        # nothing much to be done here
        self.CalcBoundingBox()

    def CalcBoundingBox(self):
        ## this isn't exact, as fonts don't scale exactly.
        dc = wx.MemoryDC()
        bitmap = wx.Bitmap(1, 1)
        dc.SelectObject(bitmap) #wxMac needs a Bitmap selected for GetTextExtent to work.
        DrawingSize = 40 # pts This effectively determines the resolution that the BB is computed to.
        ScaleFactor = float(self.Size) / DrawingSize
        self.SetFont(DrawingSize, self.Family, self.Style, self.Weight, self.Underlined, self.FaceName)
        dc.SetFont(self.Font)
        (w,h) = dc.GetTextExtent(self.String)
        w = w * ScaleFactor
        h = h * ScaleFactor
        x, y = self.ShiftFun(self.XY[0], self.XY[1], w, h, world = 1)
        self.BoundingBox = BBox.asBBox(((x, y-h ),(x + w, y)))

    def _Draw(self, dc , WorldToPixel, ScaleWorldToPixel, HTdc=None):
        (X,Y) = WorldToPixel( (self.XY) )

        # compute the font size:
        Size = abs( ScaleWorldToPixel( (self.Size, self.Size) )[1] ) # only need a y coordinate length
        ## Check to see if the font size is large enough to blow up the X font server
        ## If so, limit it. Would it be better just to not draw it?
        ## note that this limit is dependent on how much memory you have, etc.
        Size = min(Size, self.MaxFontSize)
        Size = max(Size, self.MinFontSize) # smallest size you want - default to 0

        # Draw the Text
        if not( self.DisappearWhenSmall and Size <=  self.MinFontSize) : # don't try to draw a zero sized font!
            self.SetFont(Size, self.Family, self.Style, self.Weight, self.Underlined, self.FaceName)
            dc.SetFont(self.Font)
            dc.SetTextForeground(self.Color)
            if self.BackgroundColor:
                dc.SetBackgroundMode(wx.SOLID)
                dc.SetTextBackground(self.BackgroundColor)
            else:
                dc.SetBackgroundMode(wx.TRANSPARENT)
            (w,h) = dc.GetTextExtent(self.String)
            # compute the shift, and adjust the coordinates, if neccesary
            # This had to be put in here, because it changes with Zoom, as
            # fonts don't scale exactly.
            xy = self.ShiftFun(X, Y, w, h)
            dc.DrawText(self.String, xy)

            if HTdc and self.HitAble:
                HTdc.SetPen(self.HitPen)
                HTdc.SetBrush(self.HitBrush)
                HTdc.DrawRectangle(xy, (w, h))

class ScaledTextBox(TextObjectMixin, DrawObject):
    """
    Draws a text object

    The object is scaled when zoomed.

    The hit-test is done on the entire text extent

    Bugs/Limitations:

    As fonts are scaled, they do end up a little different, so you don't
    get exactly the same picture as you scale up and down, but it's
    pretty darn close.

    On wxGTK1 on my Linux system, at least, using a font of over about
    1000 pts. brings the system to a halt. It's the Font Server using
    huge amounts of memory. My work around is to max the font size to
    1000 points, so it won't scale past there. GTK2 uses smarter font
    drawing, so that may not be an issue in future versions, so feel
    free to test. Another smarter way to do it would be to set a global
    zoom limit at that point.

    """

    def __init__(self, String,
                 Point,
                 Size,
                 Color = "Black",
                 BackgroundColor = None,
                 LineColor = 'Black',
                 LineStyle = 'Solid',
                 LineWidth = 1,
                 Width = None,
                 PadSize = None,
                 Family = wx.FONTFAMILY_MODERN,
                 Style = wx.FONTSTYLE_NORMAL,
                 Weight = wx.FONTWEIGHT_NORMAL,
                 Underlined = False,
                 Position = 'tl',
                 Alignment = "left",
                 Font = None,
                 LineSpacing = 1.0,
                 InForeground = False):
        """
        Default class constructor.

        :param `Point`: takes a 2-tuple, or a (2,) `NumPy <http://www.numpy.org/>`_
         array of point coordinates
        :param integer `Size`: size in World units
        :param `Color`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
        :param `BackgroundColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
        :param `LineColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
        :param `LineWidth`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetLineWidth`
        :param `Width`: width in pixels or ``None``, text will be wrapped to
         the given width.
        :param `PadSize`: padding in world units or ``None``, if specified it
         will creating a space (margin) around the text
        :param wx.FontFamily `Family`: a valid :ref:`wx.FontFamily`
        :param wx.FontStyle `Style`: a valid :ref:`wx.FontStyle`
        :param wx.FontWeight `Weight`: a valid :ref:`wx.FontWeight`
        :param boolean `Underlined`: underline the text
        :param string `Position`: a two character string indicating where in
         relation to the coordinates the box should be oriented

         ============== ==========================
         1st character  Meaning
         ============== ==========================
         ``t``          top
         ``c``          center
         ``b``          bottom
         ============== ==========================

         ============== ==========================
         2nd character  Meaning
         ============== ==========================
         ``l``          left
         ``c``          center
         ``r``          right
         ============== ==========================

        :param `Alignment`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetLineWidth`
        :param wx.Font `Font`: alternatively a valid :class:`wx.Font` can be defined
         in which case the above will be ignored
        :param float `LineSpacing`: the line space to be used
        :param boolean `InForeground`: should object be in foreground

        """
        DrawObject.__init__(self,InForeground)

        self.XY = N.array(Point, N.float)
        self.Size = Size
        self.Color = Color
        self.BackgroundColor = BackgroundColor
        self.LineColor = LineColor
        self.LineStyle = LineStyle
        self.LineWidth = LineWidth
        self.Width = Width
        if PadSize is None: # the default is just a little bit of padding
            self.PadSize = Size/10.0
        else:
            self.PadSize = float(PadSize)
        self.Family = Family
        self.Style = Style
        self.Weight = Weight
        self.Underlined = Underlined
        self.Alignment = Alignment.lower()
        self.LineSpacing = float(LineSpacing)
        self.Position = Position

        if not Font:
            self.FaceName = ''
        else:
            self.FaceName           =  Font.GetFaceName()
            self.Family             =  Font.GetFamily()
            self.Style              =  Font.GetStyle()
            self.Underlined         =  Font.GetUnderlined()
            self.Weight             =  Font.GetWeight()

        # Experimental max font size value on wxGTK2: this works OK on
        # my system. If it's a lot  larger, there is a crash, with the
        # message:
        #
        # The application 'FloatCanvasDemo.py' lost its
        # connection to the display :0.0; most likely the X server was
        # shut down or you killed/destroyed the application.
        #
        # Windows and OS-X seem to be better behaved in this regard.
        # They may not draw it, but they don't crash either!

        self.MaxFontSize = 1000
        self.MinFontSize = 1 # this can be changed to set a larger minimum size
        self.DisappearWhenSmall = True

        self.ShiftFun = self.ShiftFunDict[Position]

        self.String = String
        self.LayoutText()
        self.CalcBoundingBox()

        self.SetPen(LineColor,LineStyle,LineWidth)
        self.SetBrush(BackgroundColor, "Solid")


    def WrapToWidth(self):
        dc = wx.MemoryDC()
        bitmap = wx.Bitmap(1, 1)
        dc.SelectObject(bitmap) #wxMac needs a Bitmap selected for GetTextExtent to work.
        DrawingSize = self.LayoutFontSize # pts This effectively determines the resolution that the BB is computed to.
        ScaleFactor = float(self.Size) / DrawingSize
        Width = (self.Width - 2*self.PadSize) / ScaleFactor #Width to wrap to
        self.SetFont(DrawingSize, self.Family, self.Style, self.Weight, self.Underlined, self.FaceName)
        dc.SetFont(self.Font)
        NewStrings = []
        for s in self.Strings:
            #beginning = True
            text = s.split(" ")
            text.reverse()
            LineLength = 0
            NewText = text[-1]
            del text[-1]
            while text:
                w  = dc.GetTextExtent(' ' + text[-1])[0]
                if LineLength + w <= Width:
                    NewText += ' '
                    NewText += text[-1]
                    LineLength = dc.GetTextExtent(NewText)[0]
                else:
                    NewStrings.append(NewText)
                    NewText = text[-1]
                    LineLength = dc.GetTextExtent(text[-1])[0]
                del text[-1]
            NewStrings.append(NewText)
        self.Strings = NewStrings

    def ReWrap(self, Width):
        self.Width = Width
        self.LayoutText()

    def LayoutText(self):
        """
        Calculates the positions of the words of text.

        This isn't exact, as fonts don't scale exactly.
        To help this, the position of each individual word
        is stored separately, so that the general layout stays
        the same in world coordinates, as the fonts scale.

        """
        self.Strings = self.String.split("\n")
        if self.Width:
            self.WrapToWidth()

        dc = wx.MemoryDC()
        bitmap = wx.Bitmap(1, 1)
        dc.SelectObject(bitmap) #wxMac needs a Bitmap selected for GetTextExtent to work.

        DrawingSize = self.LayoutFontSize # pts This effectively determines the resolution that the BB is computed to.
        ScaleFactor = float(self.Size) / DrawingSize

        self.SetFont(DrawingSize, self.Family, self.Style, self.Weight, self.Underlined, self.FaceName)
        dc.SetFont(self.Font)
        TextHeight = dc.GetTextExtent("X")[1]
        SpaceWidth = dc.GetTextExtent(" ")[0]
        LineHeight = TextHeight * self.LineSpacing

        LineWidths = N.zeros((len(self.Strings),), N.float)
        y = 0
        Words = []
        AllLinePoints = []

        for i, s in enumerate(self.Strings):
            LineWidths[i] = 0
            LineWords = s.split(" ")
            LinePoints = N.zeros((len(LineWords),2), N.float)
            for j, word in enumerate(LineWords):
                if j > 0:
                    LineWidths[i] += SpaceWidth
                Words.append(word)
                LinePoints[j] = (LineWidths[i], y)
                w = dc.GetTextExtent(word)[0]
                LineWidths[i] += w
            y -= LineHeight
            AllLinePoints.append(LinePoints)
        TextWidth = N.maximum.reduce(LineWidths)
        self.Words = Words

        if self.Width is None:
            BoxWidth = TextWidth * ScaleFactor + 2*self.PadSize
        else: # use the defined Width
            BoxWidth = self.Width
        Points = N.zeros((0,2), N.float)

        for i, LinePoints in enumerate(AllLinePoints):
            ## Scale to World Coords.
            LinePoints *= (ScaleFactor, ScaleFactor)
            if self.Alignment == 'left':
                LinePoints[:,0] += self.PadSize
            elif self.Alignment == 'center':
                LinePoints[:,0] += (BoxWidth - LineWidths[i]*ScaleFactor)/2.0
            elif self.Alignment == 'right':
                LinePoints[:,0] += (BoxWidth - LineWidths[i]*ScaleFactor-self.PadSize)
            Points = N.concatenate((Points, LinePoints))

        BoxHeight = -(Points[-1,1] - (TextHeight * ScaleFactor)) + 2*self.PadSize
        #(x,y) = self.ShiftFun(self.XY[0], self.XY[1], BoxWidth, BoxHeight, world=1)
        Points += (0, -self.PadSize)
        self.Points = Points
        self.BoxWidth = BoxWidth
        self.BoxHeight = BoxHeight
        self.CalcBoundingBox()

    def CalcBoundingBox(self):
        """Calculates the Bounding Box"""
        w, h = self.BoxWidth, self.BoxHeight
        x, y = self.ShiftFun(self.XY[0], self.XY[1], w, h, world=1)
        self.BoundingBox = BBox.asBBox(((x, y-h ),(x + w, y)))

    def GetBoxRect(self):
        wh = (self.BoxWidth, self.BoxHeight)
        xy = (self.BoundingBox[0,0], self.BoundingBox[1,1])

        return (xy, wh)

    def _Draw(self, dc , WorldToPixel, ScaleWorldToPixel, HTdc=None):
        xy, wh = self.GetBoxRect()

        Points = self.Points + xy
        Points = WorldToPixel(Points)
        xy = WorldToPixel(xy)
        wh = ScaleWorldToPixel(wh) * (1,-1)

        # compute the font size:
        Size = abs( ScaleWorldToPixel( (self.Size, self.Size) )[1] ) # only need a y coordinate length
        ## Check to see if the font size is large enough to blow up the X font server
        ## If so, limit it. Would it be better just to not draw it?
        ## note that this limit is dependent on how much memory you have, etc.
        Size = min(Size, self.MaxFontSize)

        Size = max(Size, self.MinFontSize) # smallest size you want - default to 1

        # Draw The Box
        if (self.LineStyle and self.LineColor) or self.BackgroundColor:
            dc.SetBrush(self.Brush)
            dc.SetPen(self.Pen)
            dc.DrawRectangle(xy , wh)

        # Draw the Text
        if not( self.DisappearWhenSmall and Size <=  self.MinFontSize) : # don't try to draw a zero sized font!
            self.SetFont(Size, self.Family, self.Style, self.Weight, self.Underlined, self.FaceName)
            dc.SetFont(self.Font)
            dc.SetTextForeground(self.Color)
            dc.SetBackgroundMode(wx.TRANSPARENT)
            dc.DrawTextList(self.Words, Points)

        # Draw the hit box.
        if HTdc and self.HitAble:
            HTdc.SetPen(self.HitPen)
            HTdc.SetBrush(self.HitBrush)
            HTdc.DrawRectangle(xy, wh)

class Bitmap(TextObjectMixin, DrawObject):
    """
    Draws a bitmap

    The size is fixed, and does not scale with the drawing.

    """

    def __init__(self, Bitmap, XY,
                 Position='tl',
                 InForeground=False):
        """
        Default class constructor.

        :param wx.Bitmap `Bitmap`: the bitmap to be drawn
        :param `XY`: the (x, y) coordinate of the corner of the bitmap, or a 2-tuple,
         or a (2,) `NumPy <http://www.numpy.org/>`_ array
        :param string `Position`: a two character string indicating where in relation to the coordinates
         the bitmap should be oriented

         ============== ==========================
         1st character  Meaning
         ============== ==========================
         ``t``          top
         ``c``          center
         ``b``          bottom
         ============== ==========================

         ============== ==========================
         2nd character  Meaning
         ============== ==========================
         ``l``          left
         ``c``          center
         ``r``          right
         ============== ==========================

        :param boolean `InForeground`: should object be in foreground

        """

        DrawObject.__init__(self,InForeground)

        if type(Bitmap) == wx.Bitmap:
            self.Bitmap = Bitmap
        elif type(Bitmap) == wx.Image:
            self.Bitmap = wx.Bitmap(Bitmap)

        # Note the BB is just the point, as the size in World coordinates is not fixed
        self.BoundingBox = BBox.asBBox( (XY,XY) )

        self.XY = XY

        (self.Width, self.Height) = self.Bitmap.GetWidth(), self.Bitmap.GetHeight()
        self.ShiftFun = self.ShiftFunDict[Position]

    def _Draw(self, dc , WorldToPixel, ScaleWorldToPixel, HTdc=None):
        XY = WorldToPixel(self.XY)
        XY = self.ShiftFun(XY[0], XY[1], self.Width, self.Height)
        dc.DrawBitmap(self.Bitmap, XY, True)
        if HTdc and self.HitAble:
            HTdc.SetPen(self.HitPen)
            HTdc.SetBrush(self.HitBrush)
            HTdc.DrawRectangle(XY, (self.Width, self.Height) )

class ScaledBitmap(TextObjectMixin, DrawObject):
    """
    Draws a scaled bitmap

    The size scales with the drawing

    """

    def __init__(self,
                 Bitmap,
                 XY,
                 Height,
                 Position = 'tl',
                 InForeground = False):
        """
        Default class constructor.

        :param wx.Bitmap `Bitmap`: the bitmap to be drawn
        :param `XY`: the (x, y) coordinate of the corner of the scaled bitmap,
         or a 2-tuple, or a (2,) `NumPy <http://www.numpy.org/>`_ array
        :param `Height`: height to be used, width is calculated from the aspect ratio of the bitmap
        :param string `Position`: a two character string indicating where in relation to the coordinates
         the bitmap should be oriented

         ============== ==========================
         1st character  Meaning
         ============== ==========================
         ``t``          top
         ``c``          center
         ``b``          bottom
         ============== ==========================

         ============== ==========================
         2nd character  Meaning
         ============== ==========================
         ``l``          left
         ``c``          center
         ``r``          right
         ============== ==========================

        :param boolean `InForeground`: should object be in foreground

        """

        DrawObject.__init__(self,InForeground)

        if type(Bitmap) == wx.Bitmap:
            self.Image = Bitmap.ConvertToImage()
        elif type(Bitmap) == wx.Image:
            self.Image = Bitmap
        else:
            raise ValueError("'Bitmap' must be a wx.Bitmap or wx.Image object not %s" % type(Bitmap))

        self.XY = XY
        self.Height = Height
        (self.bmpWidth, self.bmpHeight) = float(self.Image.GetWidth()), float(self.Image.GetHeight())
        self.Width = self.bmpWidth / self.bmpHeight * Height
        self.ShiftFun = self.ShiftFunDict[Position]
        self.CalcBoundingBox()
        self.ScaledBitmap = None
        self.ScaledHeight = None

    def CalcBoundingBox(self):
        """Calculate the bounding box."""
        ## this isn't exact, as fonts don't scale exactly.
        w, h = self.Width, self.Height
        x, y = self.ShiftFun(self.XY[0], self.XY[1], w, h, world = 1)
        self.BoundingBox = BBox.asBBox( ( (x, y-h ), (x + w, y) ) )


    def _Draw(self, dc , WorldToPixel, ScaleWorldToPixel, HTdc=None):
        XY = WorldToPixel(self.XY)
        H = ScaleWorldToPixel(self.Height)[0]
        W = H * (self.bmpWidth / self.bmpHeight)
        if (self.ScaledBitmap is None) or (H != self.ScaledHeight) :
            self.ScaledHeight = H
            Img = self.Image.Scale(W, H)
            self.ScaledBitmap = wx.Bitmap(Img)

        XY = self.ShiftFun(XY[0], XY[1], W, H)
        dc.DrawBitmap(self.ScaledBitmap, XY, True)
        if HTdc and self.HitAble:
            HTdc.SetPen(self.HitPen)
            HTdc.SetBrush(self.HitBrush)
            HTdc.DrawRectangle(XY, (W, H) )

class ScaledBitmap2(TextObjectMixin, DrawObject, ):
    """
    Draws a scaled bitmap

    An alternative scaled bitmap that only scaled the required amount of
    the main bitmap when zoomed in: EXPERIMENTAL!

    """

    def __init__(self,
                 Bitmap,
                 XY,
                 Height,
                 Width=None,
                 Position = 'tl',
                 InForeground = False):
        """
        Default class constructor.

        :param wx.Bitmap `Bitmap`: the bitmap to be drawn
        :param `XY`: the (x, y) coordinate of the corner of the scaled bitmap,
         or a 2-tuple, or a (2,) `NumPy <http://www.numpy.org/>`_ array
        :param `Height`: height to be used
        :param `Width`: width to be used, if ``None`` width is calculated from the aspect ratio of the bitmap
        :param string `Position`: a two character string indicating where in relation to the coordinates
         the bitmap should be oriented

         ============== ==========================
         1st character  Meaning
         ============== ==========================
         ``t``          top
         ``c``          center
         ``b``          bottom
         ============== ==========================

         ============== ==========================
         2nd character  Meaning
         ============== ==========================
         ``l``          left
         ``c``          center
         ``r``          right
         ============== ==========================

        :param boolean `InForeground`: should object be in foreground

        """

        DrawObject.__init__(self,InForeground)

        if type(Bitmap) == wx.Bitmap:
            self.Image = Bitmap.ConvertToImage()
        elif type(Bitmap) == wx.Image:
            self.Image = Bitmap

        self.XY = N.array(XY, N.float)
        self.Height = Height
        (self.bmpWidth, self.bmpHeight) = float(self.Image.GetWidth()), float(self.Image.GetHeight())
        self.bmpWH = N.array((self.bmpWidth, self.bmpHeight), N.int32)
        ## fixme: this should all accommodate different scales for X and Y
        if Width is None:
            self.BmpScale = float(self.bmpHeight) / Height
            self.Width = self.bmpWidth / self.BmpScale
        self.WH = N.array((self.Width, Height), N.float)
        ##fixme: should this have a y = -1 to shift to y-up?
        self.BmpScale = self.bmpWH / self.WH

        #print("bmpWH:", self.bmpWH)
        #print("Width, Height:", self.WH)
        #print("self.BmpScale", self.BmpScale)
        self.ShiftFun = self.ShiftFunDict[Position]
        self.CalcBoundingBox()
        self.ScaledBitmap = None # cache of the last existing scaled bitmap

    def CalcBoundingBox(self):
        """Calculate the bounding box."""
        ## this isn't exact, as fonts don't scale exactly.
        w,h = self.Width, self.Height
        x, y = self.ShiftFun(self.XY[0], self.XY[1], w, h, world = 1)
        self.BoundingBox = BBox.asBBox( ((x, y-h ), (x + w, y)) )

    def WorldToBitmap(self, Pw):
        """Computes the bitmap coords from World coords."""
        delta = Pw - self.XY
        Pb = delta * self.BmpScale
        Pb *= (1, -1) ##fixme: this may only works for Yup projection!
                      ##       and may only work for top left position

        return Pb.astype(N.int_)

    def _DrawEntireBitmap(self, dc , WorldToPixel, ScaleWorldToPixel, HTdc):
        """
        this is pretty much the old code

        Scales and Draws the entire bitmap.

        """
        XY = WorldToPixel(self.XY)
        H = ScaleWorldToPixel(self.Height)[0]
        W = H * (self.bmpWidth / self.bmpHeight)
        if (self.ScaledBitmap is None) or (self.ScaledBitmap[0] != (0, 0, self.bmpWidth, self.bmpHeight, W, H) ):
        #if True: #fixme: (self.ScaledBitmap is None) or (H != self.ScaledHeight) :
            self.ScaledHeight = H
            #print("Scaling to:", W, H)
            Img = self.Image.Scale(W, H)
            bmp = wx.Bitmap(Img)
            self.ScaledBitmap = ((0, 0, self.bmpWidth, self.bmpHeight , W, H), bmp)# this defines the cached bitmap
        else:
            #print("Using Cached bitmap")
            bmp = self.ScaledBitmap[1]
        XY = self.ShiftFun(XY[0], XY[1], W, H)
        dc.DrawBitmap(bmp, XY, True)
        if HTdc and self.HitAble:
            HTdc.SetPen(self.HitPen)
            HTdc.SetBrush(self.HitBrush)
            HTdc.DrawRectangle(XY, (W, H) )

    def _DrawSubBitmap(self, dc , WorldToPixel, ScaleWorldToPixel, HTdc):
        """
        Subsets just the part of the bitmap that is visible
        then scales and draws that.

        """
        BBworld = BBox.asBBox(self._Canvas.ViewPortBB)
        BBbitmap = BBox.fromPoints(self.WorldToBitmap(BBworld))

        XYs = WorldToPixel(self.XY)
        # figure out subimage:
        # fixme: this should be able to be done more succinctly!

        if BBbitmap[0,0] < 0:
            Xb = 0
        elif BBbitmap[0,0] >  self.bmpWH[0]: # off the bitmap
            Xb = 0
        else:
            Xb = BBbitmap[0,0]
            XYs[0] = 0 # draw at origin

        if BBbitmap[0,1] < 0:
            Yb = 0
        elif BBbitmap[0,1] >  self.bmpWH[1]: # off the bitmap
            Yb = 0
            ShouldDraw = False
        else:
            Yb = BBbitmap[0,1]
            XYs[1] = 0 # draw at origin

        if BBbitmap[1,0] < 0:
            #off the screen --  This should never happen!
            Wb = 0
        elif BBbitmap[1,0] > self.bmpWH[0]:
            Wb = self.bmpWH[0] - Xb
        else:
            Wb = BBbitmap[1,0] - Xb

        if BBbitmap[1,1] < 0:
            # off the screen --  This should never happen!
            Hb = 0
            ShouldDraw = False
        elif BBbitmap[1,1] > self.bmpWH[1]:
            Hb = self.bmpWH[1] - Yb
        else:
            Hb = BBbitmap[1,1] - Yb

        FullHeight = ScaleWorldToPixel(self.Height)[0]
        scale = float(FullHeight) / float(self.bmpWH[1])
        Ws = int(scale * Wb + 0.5) # add the 0.5 to  round
        Hs = int(scale * Hb + 0.5)
        if (self.ScaledBitmap is None) or (self.ScaledBitmap[0] != (Xb, Yb, Wb, Hb, Ws, Ws) ):
            Img = self.Image.GetSubImage(wx.Rect(Xb, Yb, Wb, Hb))
            #print("rescaling with High quality")
            Img.Rescale(Ws, Hs, quality=wx.IMAGE_QUALITY_HIGH)
            bmp = wx.Bitmap(Img)
            self.ScaledBitmap = ((Xb, Yb, Wb, Hb, Ws, Ws), bmp)# this defines the cached bitmap
            #XY = self.ShiftFun(XY[0], XY[1], W, H)
            #fixme: get the shiftfun working!
        else:
            #print("Using cached bitmap")
            ##fixme: The cached bitmap could be used if the one needed is the same scale, but
            ##       a subset of the cached one.
            bmp = self.ScaledBitmap[1]
        dc.DrawBitmap(bmp, XYs, True)

        if HTdc and self.HitAble:
            HTdc.SetPen(self.HitPen)
            HTdc.SetBrush(self.HitBrush)
            HTdc.DrawRectangle(XYs, (Ws, Hs) )

    def _Draw(self, dc , WorldToPixel, ScaleWorldToPixel, HTdc=None):
        BBworld = BBox.asBBox(self._Canvas.ViewPortBB)
        ## first see if entire bitmap is displayed:
        if  BBworld.Inside(self.BoundingBox):
            #print("Drawing entire bitmap with old code")
            self._DrawEntireBitmap(dc , WorldToPixel, ScaleWorldToPixel, HTdc)
            return None
        elif BBworld.Overlaps(self.BoundingBox):
            #BBbitmap = BBox.fromPoints(self.WorldToBitmap(BBworld))
            #print("Drawing a sub-bitmap")
            self._DrawSubBitmap(dc , WorldToPixel, ScaleWorldToPixel, HTdc)
        else:
            #print("Not Drawing -- no part of image is showing")
            pass

class DotGrid:
    """
    An example of a Grid Object -- it is set on the FloatCanvas with one of::

        FloatCanvas.GridUnder = Grid
        FloatCanvas.GridOver = Grid

    It will be drawn every time, regardless of the viewport.

    In its _Draw method, it computes what to draw, given the ViewPortBB
    of the Canvas it's being drawn on.

    """
    def __init__(self, Spacing, Size = 2, Color = "Black", Cross=False, CrossThickness = 1):

        self.Spacing = N.array(Spacing, N.float)
        self.Spacing.shape = (2,)
        self.Size = Size
        self.Color = Color
        self.Cross = Cross
        self.CrossThickness = CrossThickness

    def CalcPoints(self, Canvas):
        ViewPortBB = Canvas.ViewPortBB

        Spacing = self.Spacing

        minx, miny = N.floor(ViewPortBB[0] / Spacing) * Spacing
        maxx, maxy = N.ceil(ViewPortBB[1] / Spacing) * Spacing

        ##fixme: this could use vstack or something with numpy
        x = N.arange(minx, maxx+Spacing[0], Spacing[0]) # making sure to get the last point
        y = N.arange(miny, maxy+Spacing[1], Spacing[1]) # an extra is OK
        Points = N.zeros((len(y), len(x), 2), N.float)
        x.shape = (1,-1)
        y.shape = (-1,1)
        Points[:,:,0] += x
        Points[:,:,1] += y
        Points.shape = (-1,2)

        return Points

    def _Draw(self, dc, Canvas):
        Points = self.CalcPoints(Canvas)

        Points = Canvas.WorldToPixel(Points)

        dc.SetPen(wx.Pen(self.Color,self.CrossThickness))

        if self.Cross: # Use cross shaped markers
            #Horizontal lines
            LinePoints = N.concatenate((Points + (self.Size,0),Points + (-self.Size,0)),1)
            dc.DrawLineList(LinePoints)
            # Vertical Lines
            LinePoints = N.concatenate((Points + (0,self.Size),Points + (0,-self.Size)),1)
            dc.DrawLineList(LinePoints)
            pass
        else: # use dots
            ## Note: this code borrowed from Pointset -- it really shouldn't be repeated here!.
            if self.Size <= 1:
                dc.DrawPointList(Points)
            elif self.Size <= 2:
                dc.DrawPointList(Points + (0,-1))
                dc.DrawPointList(Points + (0, 1))
                dc.DrawPointList(Points + (1, 0))
                dc.DrawPointList(Points + (-1,0))
            else:
                dc.SetBrush(wx.Brush(self.Color))
                radius = int(round(self.Size/2))
                ##fixme: I really should add a DrawCircleList to wxPython
                if len(Points) > 100:
                    xy = Points
                    xywh = N.concatenate((xy-radius, N.ones(xy.shape) * self.Size ), 1 )
                    dc.DrawEllipseList(xywh)
                else:
                    for xy in Points:
                        dc.DrawCircle(xy[0],xy[1], radius)

class Arc(XYObjectMixin, LineAndFillMixin, DrawObject):
    """
    Draws an arc of a circle, centered on point ``CenterXY``, from
    the first point ``StartXY`` to the second ``EndXY``.

    The arc is drawn in an anticlockwise direction from the start point to
    the end point.

    """
    def __init__(self,
                 StartXY,
                 EndXY,
                 CenterXY,
                 LineColor = "Black",
                 LineStyle = "Solid",
                 LineWidth    = 1,
                 FillColor    = None,
                 FillStyle    = "Solid",
                 InForeground = False):
        """
        Default class constructor.

        :param `StartXY`: start point, takes a 2-tuple, or a (2,)
         `NumPy <http://www.numpy.org/>`_ array of point coordinates
        :param `EndXY`: end point, takes a 2-tuple, or a (2,)
         `NumPy <http://www.numpy.org/>`_ array of point coordinates
        :param `CenterXY`: center point, takes a 2-tuple, or a (2,)
         `NumPy <http://www.numpy.org/>`_ array of point coordinates
        :param `LineColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
        :param `LineStyle`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetLineStyle`
        :param `LineWidth`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetLineWidth`
        :param `FillColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
        :param `FillStyle`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetFillStyle`
        :param boolean `InForeground`: should object be in foreground

        """

        DrawObject.__init__(self, InForeground)

        # There is probably a more elegant way to do this next section
        # The bounding box just gets set to the WH of a circle, with center at CenterXY
        # This is suitable for a pie chart as it will be a circle anyway
        radius = N.sqrt( (StartXY[0]-CenterXY[0])**2 + (StartXY[1]-CenterXY[1])**2 )
        minX = CenterXY[0]-radius
        minY = CenterXY[1]-radius
        maxX = CenterXY[0]+radius
        maxY = CenterXY[1]+radius
        XY = [minX,minY]
        WH = [maxX-minX,maxY-minY]

        self.XY = N.asarray( XY, N.float).reshape((2,))
        self.WH = N.asarray( WH, N.float).reshape((2,))

        self.StartXY = N.asarray(StartXY, N.float).reshape((2,))
        self.CenterXY = N.asarray(CenterXY, N.float).reshape((2,))
        self.EndXY = N.asarray(EndXY, N.float).reshape((2,))

        #self.BoundingBox = array((self.XY, (self.XY + self.WH)), Float)
        self.CalcBoundingBox()

        #Finish the setup; allocate color,style etc.
        self.LineColor = LineColor
        self.LineStyle = LineStyle
        self.LineWidth = LineWidth
        self.FillColor = FillColor
        self.FillStyle = FillStyle

        self.HitLineWidth = max(LineWidth,self.MinHitLineWidth)

        self.SetPen(LineColor, LineStyle, LineWidth)
        self.SetBrush(FillColor, FillStyle)                  #Why isn't this working ???

    def Move(self, Delta):
        """
        Move the object by delta

        :param `Delta`: delta is a (dx, dy) pair. Ideally a `NumPy <http://www.numpy.org/>`_
         array of shape (2,)

        """

        Delta = N.asarray(Delta, N.float)
        self.XY += Delta
        self.StartXY += Delta
        self.CenterXY += Delta
        self.EndXY += Delta
        self.BoundingBox += Delta

        if self._Canvas:
            self._Canvas.BoundingBoxDirty = True

    def _Draw(self, dc , WorldToPixel, ScaleWorldToPixel, HTdc=None):
        self.SetUpDraw(dc , WorldToPixel, ScaleWorldToPixel, HTdc)
        StartXY = WorldToPixel(self.StartXY)
        EndXY = WorldToPixel(self.EndXY)
        CenterXY = WorldToPixel(self.CenterXY)

        dc.DrawArc(StartXY, EndXY, CenterXY)
        if HTdc and self.HitAble:
            HTdc.DrawArc(StartXY, EndXY, CenterXY)

    def CalcBoundingBox(self):
        """Calculate the bounding box."""
        self.BoundingBox = BBox.asBBox( N.array((self.XY, (self.XY + self.WH) ),
                                                N.float) )
        if self._Canvas:
            self._Canvas.BoundingBoxDirty = True


class PieChart(XYObjectMixin, LineOnlyMixin, DrawObject):
    """
    This is DrawObject for a pie chart

    You can pass in a bunch of values, and it will draw a pie chart for
    you, and it will make the chart, scaling the size of each "slice" to
    match your values.
    """

    ##fixme: this should be a longer and better designed set.
    ##       Maybe one from: http://geography.uoregon.edu/datagraphics/color_scales.htm
    DefaultColorList = Colors.CategoricalColor1
    #["Red", "Green", "Blue", "Purple", "Yellow", "Cyan"]

    def __init__(self,
                 XY,
                 Diameter,
                 Values,
                 FillColors=None,
                 FillStyles=None,
                 LineColor = None,
                 LineStyle = "Solid",
                 LineWidth    = 1,
                 Scaled = True,
                 InForeground = False):
        """
        Default class constructor.

        :param `XY`: The (x,y) coords of the center of the chart
        :param `Diameter`: The diamter of the chart in worls coords, unless you
                 set "Scaled" to False, in which case it's in pixel coords.
        :param `Values`: sequence of values you want to make the chart of.
        :param `FillColors`: sequence of colors you want the slices. If
                 None, it will choose (no guarantee you'll like them!)
        :param `FillStyles`: Fill style you want ("Solid", "Hash", etc)
        :param `LineColor`: Color of lines separating the slices
        :param `LineStyle`: style of lines separating the slices
        :param `LineWidth`: With of lines separating the slices
        :param `Scaled`: Do you want the pie to scale when zooming?
                 or stay the same size in pixels?
        :param `InForeground`: Should it be on the foreground?
        """
        DrawObject.__init__(self, InForeground)

        self.XY = N.asarray(XY, N.float).reshape( (2,) )
        self.Diameter = Diameter
        self.Values = N.asarray(Values, dtype=N.float).reshape((-1,1))
        if FillColors is None:
            FillColors = self.DefaultColorList[:len(Values)]
        if FillStyles is None:
            FillStyles = ['Solid'] * len(FillColors)
        self.FillColors = FillColors
        self.FillStyles = FillStyles
        self.LineColor = LineColor
        self.LineStyle = LineStyle

        self.Scaled = Scaled
        self.InForeground = InForeground

        self.SetPen(LineColor, LineStyle, LineWidth)
        self.SetBrushes()
        self.CalculatePoints()

    def SetFillColors(self, FillColors):
        """
        Set the FillColors and update the Brushes.

        :param `FillColors`: sequence of colors
        """
        self.FillColors = FillColors
        self.SetBrushes()

    def SetFillStyles(self, FillStyles):
        """
        Set te FillStyles and update the Brushes.

        :param `FillStyles`: Fill style you want ("Solid", "Hash", etc)
        """
        self.FillStyles = FillStyles
        self.SetBrushed()

    def SetValues(self, Values):
        """
        Set the values and calculate the points.

        :param `Values`: sequence of values you want to use for the chart
        """
        Values = N.asarray(Values, dtype=N.float).reshape((-1,1))
        self.Values = Values
        self.CalculatePoints()

    def CalculatePoints(self):
        """Calculate the points."""
        # add the zero point to start
        Values = N.vstack( ( (0,), self.Values) )
        self.Angles = 360. * Values.cumsum()/Values.sum()
        self.CalcBoundingBox()

    def SetBrushes(self):
        """Set the Brushes."""
        self.Brushes = []
        for FillColor, FillStyle in zip(self.FillColors, self.FillStyles):
            if FillColor is None or FillStyle is None:
                self.Brush = wx.TRANSPARENT_BRUSH
            else:
                self.Brushes.append(self.BrushList.setdefault( (FillColor, FillStyle),
                                                               wx.Brush( FillColor, self.FillStyleList[FillStyle] )
                                                              )
                                    )
    def CalcBoundingBox(self):
        """Calculate the bounding box."""
        if self.Scaled:
            self.BoundingBox = BBox.asBBox( ((self.XY-self.Diameter),(self.XY+self.Diameter)) )
        else:
            self.BoundingBox = BBox.asBBox((self.XY, self.XY))
        if self._Canvas:
            self._Canvas.BoundingBoxDirty = True

    def _Draw(self, dc , WorldToPixel, ScaleWorldToPixel, HTdc=None):
        CenterXY = WorldToPixel(self.XY)
        if self.Scaled:
            Diameter = ScaleWorldToPixel( (self.Diameter,self.Diameter) )[0]
        else:
            Diameter = self.Diameter
        WH = N.array((Diameter,Diameter), dtype = N.float)
        Corner = CenterXY - (WH / 2)
        dc.SetPen(self.Pen)
        for i, brush in enumerate(self.Brushes):
            dc.SetBrush( brush )
            dc.DrawEllipticArc(Corner[0], Corner[1], WH[0], WH[1], self.Angles[i], self.Angles[i+1])
        if HTdc and self.HitAble:
            if self.Scaled:
                radius = (ScaleWorldToPixel(self.Diameter)/2)[0]# just the x-coord
            else:
                radius = self.Diameter/2
            HTdc.SetPen(self.HitPen)
            HTdc.SetBrush(self.HitBrush)
            HTdc.DrawCircle(CenterXY, radius)


class Group(DrawObject):
    """
    A group of other FloatCanvas Objects

    Not all DrawObject methods may apply here.

    Note that if an object is in more than one group, it will get drawn more than once.

    """

    def __init__(self, ObjectList=[], InForeground=False, IsVisible=True):
        """
        Default class constructor.

        :param list `ObjectList`: a list of :class:`DrawObject` to be grouped
        :param boolean `InForeground`: keep in foreground
        :param boolean `IsVisible`: keep it visible

        """
        self.ObjectList = []
        DrawObject.__init__(self, InForeground, IsVisible)

        # this one uses a proprty for _Canvas...
        self._Actual_Canvas = None

        self.CalcBoundingBox()
        for obj in ObjectList:
            self.AddObject(obj)
        self.CalcBoundingBox()

    ## re-define _Canvas property so that the sub-objects get set up right
    @property
    def _Canvas(self):
        """
        getter for the _Canvas property
        """
        return self._Actual_Canvas

    @_Canvas.setter
    def _Canvas(self, canvas):
        """
        setter for Canvas property
        """
        self._Actual_Canvas = canvas
        for obj in self.ObjectList:
            obj._Canvas = canvas

    def AddObject(self, obj):
        """
        Add an object to the group.

        :param DrawObject `obj`: object to add

        """
        self.ObjectList.append(obj)
        self.BoundingBox.Merge(obj.BoundingBox)

    def AddObjects(self, Objects):
        """
        Add objects to the group.

        :param list `Objects`: a list of :class:`DrawObject` to be grouped

        """
        for o in Objects:
            self.AddObject(o)

    def CalcBoundingBox(self):
        """Calculate the bounding box."""
        if self.ObjectList:
            BB = BBox.BBox(self.ObjectList[0].BoundingBox).copy()
            for obj in self.ObjectList[1:]:
                BB.Merge(obj.BoundingBox)
        else:
            BB = BBox.NullBBox()
        self.BoundingBox = BB

    def SetColor(self, Color):
        """
        Set the Color

        :param `Color`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
         for valid values

        """
        for o in self.ObjectList:
            o.SetColor(Color)

    def SetLineColor(self, Color):
        """
        Set the LineColor

        :param `LineColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
         for valid values

        """
        for o in self.ObjectList:
            o.SetLineColor(Color)

    def SetLineStyle(self, LineStyle):
        """
        Set the LineStyle

        :param `LineStyle`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetLineStyle`
         for valid values

        """
        for o in self.ObjectList:
            o.SetLineStyle(LineStyle)

    def SetLineWidth(self, LineWidth):
        """
        Set the LineWidth

        :param integer `LineWidth`: line width in pixels

        """
        for o in self.ObjectList:
            o.SetLineWidth(LineWidth)

    def SetFillColor(self, Color):
        """
        Set the FillColor

        :param `FillColor`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetColor`
         for valid values

        """
        for o in self.ObjectList:
            o.SetFillColor(Color)

    def SetFillStyle(self, FillStyle):
        """
        Set the FillStyle

        :param `FillStyle`: see :meth:`~lib.floatcanvas.FloatCanvas.DrawObject.SetFillStyle`
         for valid values

        """
        for o in self.ObjectList:
            o.SetFillStyle(FillStyle)

    def Move(self, Delta):
        """
        Moves the object by delta, where delta is a (dx, dy) pair.

        :param `Delta`: is a (dx, dy) pair ideally a `NumPy <http://www.numpy.org/>`_
         array of shape (2, )

        """
        for obj in self.ObjectList:
            obj.Move(Delta)
        self.BoundingBox += Delta

    def Bind(self, Event, CallBackFun):
        """
        Bind an event to the Group object

        :param `Event`: see below for supported event types

         - EVT_FC_LEFT_DOWN
         - EVT_FC_LEFT_UP
         - EVT_FC_LEFT_DCLICK
         - EVT_FC_MIDDLE_DOWN
         - EVT_FC_MIDDLE_UP
         - EVT_FC_MIDDLE_DCLICK
         - EVT_FC_RIGHT_DOWN
         - EVT_FC_RIGHT_UP
         - EVT_FC_RIGHT_DCLICK
         - EVT_FC_ENTER_OBJECT
         - EVT_FC_LEAVE_OBJECT

        :param `CallBackFun`: the call back function for the event


        """
        ## slight variation on DrawObject Bind Method:
        ## fixme: There is a lot of repeated code from the DrawObject method, but
        ## it all needs a lot of cleaning up anyway.
        self.CallBackFuncs[Event] = CallBackFun
        self.HitAble = True
        self._Canvas.UseHitTest = True
        if self.InForeground and self._Canvas._ForegroundHTBitmap is None:
            self._Canvas.MakeNewForegroundHTBitmap()
        elif self._Canvas._HTBitmap is None:
            self._Canvas.MakeNewHTBitmap()
        if not self.HitColor:
            if not self._Canvas.HitColorGenerator:
                self._Canvas.HitColorGenerator = _colorGenerator()
                # first call to prevent the background color from being used.
                if six.PY2:
                    self._Canvas.HitColorGenerator.next()
                else:
                    next(self._Canvas.HitColorGenerator)
            # Set all contained objects to the same Hit color:
            if six.PY2:
                self.HitColor = self._Canvas.HitColorGenerator.next()
            else:
                self.HitColor = next(self._Canvas.HitColorGenerator)
        self._ChangeChildrenHitColor(self.ObjectList)
        # put the object in the hit dict, indexed by it's color
        if not self._Canvas.HitDict:
            self._Canvas.MakeHitDict()
        self._Canvas.HitDict[Event][self.HitColor] = (self)

    def _ChangeChildrenHitColor(self, objlist):
        for obj in objlist:
            obj.SetHitPen(self.HitColor, self.HitLineWidth)
            obj.SetHitBrush(self.HitColor)
            obj.HitAble = True

            if isinstance(obj, Group):
                self._ChangeChildrenHitColor(obj.ObjectList)

    def _Draw(self, dc , WorldToPixel, ScaleWorldToPixel = None, HTdc=None):
        for obj in self.ObjectList:
            obj._Draw(dc, WorldToPixel, ScaleWorldToPixel, HTdc)
