Python Paint Program

# Written by: QuantumPhysics
# Date Written: 10/06/12

# includes wxWidgets module
import wx

class PaintWindow(wx.Window):
# array of colors available to draw
colours = ['Black', 'Yellow', 'Red', 'Green', 'Blue', 'Purple',
'Brown', 'Aquamarine', 'Forest Green', 'Light Blue', 'Goldenrod',
'Cyan', 'Orange', 'Navy', 'Light Grey', 'ClearScreen']
# color quantity
thicknesses = [1, 2, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128]

def __init__(self, parent):
# creates paint window
super(PaintWindow, self).__init__(parent,
style=wx.NO_FULL_REPAINT_ON_RESIZE)
self.initDrawing()
self.makeMenu()
# binds key_down and up events
self.bindEvents()
self.initBuffer()

def initDrawing(self):
self.SetBackgroundColour('WHITE')
self.currentThickness = self.thicknesses[0]
self.currentColour = self.colours[0]
self.lines = []
self.previousPosition = (0, 0)

def bindEvents(self):
for event, handler in [
# creates bind event for left button down
(wx.EVT_LEFT_DOWN, self.onLeftDown),
# creates bind event once left button is released
(wx.EVT_LEFT_UP, self.onLeftUp),
# creates bind event for drawing (moving cursor)
(wx.EVT_MOTION, self.onMotion),
# creates bind event for right button up
(wx.EVT_RIGHT_UP, self.onRightUp),
(wx.EVT_SIZE, self.onSize),
(wx.EVT_IDLE, self.onIdle),
(wx.EVT_PAINT, self.onPaint),
# creates event to close window after 'x' is selected
(wx.EVT_WINDOW_DESTROY, self.cleanup)]:
self.Bind(event, handler)

def initBuffer(self):
# gets size of window
size = self.GetClientSize()
# sets window to empty canvas .bmp x-width, y-height
self.buffer = wx.EmptyBitmap(size.width, size.height)
dc = wx.BufferedDC(None, self.buffer)
dc.SetBackground(wx.Brush(self.GetBackgroundColour()))
dc.Clear()
self.drawLines(dc, *self.lines)
self.reInitBuffer = False

def makeMenu(self):
# creates menu on right click
self.menu = wx.Menu()
# sets selection for items (colors) in the runtime window on right click
self.idToColourMap = self.addCheckableMenuItems(self.menu,
self.colours)
# updates screen once a new color is selected
self.bindMenuEvents(menuHandler=self.onMenuSetColour,
updateUIHandler=self.onCheckMenuColours,
ids=self.idToColourMap.keys())
self.menu.Break()
self.idToThicknessMap = self.addCheckableMenuItems(self.menu,
self.thicknesses)
self.bindMenuEvents(menuHandler=self.onMenuSetThickness,
updateUIHandler=self.onCheckMenuThickness,
ids=self.idToThicknessMap.keys())

# adds a static surpressor to conditions
@staticmethod
def addCheckableMenuItems(menu, items):

idToItemMapping = {}
for item in items:
menuId = wx.NewId()
idToItemMapping[menuId] = item
menu.Append(menuId, str(item), kind=wx.ITEM_CHECK)
return idToItemMapping

def bindMenuEvents(self, menuHandler, updateUIHandler, ids):

sortedIds = sorted(ids)
firstId, lastId = sortedIds[0], sortedIds[-1]
for event, handler in \
[(wx.EVT_MENU_RANGE, menuHandler),
(wx.EVT_UPDATE_UI_RANGE, updateUIHandler)]:
self.Bind(event, handler, id=firstId, id2=lastId)

def onLeftDown(self, event):
# draw line
self.currentLine = []
self.previousPosition = event.GetPositionTuple()
self.CaptureMouse()

def onLeftUp(self, event):
# close motion, stop drawing, wait for event
if self.HasCapture():
self.lines.append((self.currentColour, self.currentThickness,
self.currentLine))
self.currentLine = []
self.ReleaseMouse()

def onRightUp(self, event):
# if right button is clicked then make wx.menu to select colors
self.PopupMenu(self.menu)

def onMotion(self, event):

if event.Dragging() and event.LeftIsDown():
dc = wx.BufferedDC(wx.ClientDC(self), self.buffer)
currentPosition = event.GetPositionTuple()
lineSegment = self.previousPosition + currentPosition
self.drawLines(dc, (self.currentColour, self.currentThickness,
[lineSegment]))
self.currentLine.append(lineSegment)
self.previousPosition = currentPosition

def onSize(self, event):

self.reInitBuffer = True

def onIdle(self, event):

if self.reInitBuffer:
self.initBuffer()
self.Refresh(False)

def onPaint(self, event):


dc = wx.BufferedPaintDC(self, self.buffer)

def cleanup(self, event):
if hasattr(self, "menu"):
self.menu.Destroy()
del self.menu

def onCheckMenuColours(self, event):
colour = self.idToColourMap[event.GetId()]
event.Check(colour == self.currentColour)

def onCheckMenuThickness(self, event):
thickness = self.idToThicknessMap[event.GetId()]
event.Check(thickness == self.currentThickness)

def onMenuSetColour(self, event):
self.currentColour = self.idToColourMap[event.GetId()]

def onMenuSetThickness(self, event):
self.currentThickness = self.idToThicknessMap[event.GetId()]

@staticmethod
def drawLines(dc, *lines):
dc.BeginDrawing()
for colour, thickness, lineSegments in lines:
pen = wx.Pen(wx.NamedColour(colour), thickness, wx.SOLID)
dc.SetPen(pen)
for lineSegment in lineSegments:
dc.DrawLine(*lineSegment)
dc.EndDrawing()


class PaintFrame(wx.Frame):
def __init__(self, parent=None):
super(PaintFrame, self).__init__(parent, title="Paint - Version 1.0 - QuantumPhysics",
size=(800,600),
style=wx.DEFAULT_FRAME_STYLE|wx.NO_FULL_REPAINT_ON_RESIZE)
doodle = PaintWindow(self)


if __name__ == '__main__':
app = wx.App()
frame = PaintFrame()
frame.Show()
app.MainLoop()