Demo/turtle/tdemo_colormixer.py

   1 # colormixer
   2
   3 from turtle import Screen, Turtle, mainloop
   4
   5 class ColorTurtle(Turtle):
   6
   7     def __init__(self, x, y):
   8         Turtle.__init__(self)
   9         self.shape("turtle")
  10         self.resizemode("user")
  11         self.shapesize(3,3,5)
  12         self.pensize(10)
  13         self._color = [0,0,0]
  14         self.x = x
  15         self._color[x] = y
  16         self.color(self._color)
  17         self.speed(0)
  18         self.left(90)
  19         self.pu()
  20         self.goto(x,0)
  21         self.pd()
  22         self.sety(1)
  23         self.pu()
  24         self.sety(y)
  25         self.pencolor("gray25")
  26         self.ondrag(self.shift)
  27
  28     def shift(self, x, y):
  29         self.sety(max(0,min(y,1)))
  30         self._color[self.x] = self.ycor()
  31         self.fillcolor(self._color)
  32         setbgcolor()
  33
  34 def setbgcolor():
  35     screen.bgcolor(red.ycor(), green.ycor(), blue.ycor())
  36
  37 def main():
  38     global screen, red, green, blue
  39     screen = Screen()
  40     screen.delay(0)
  41     screen.setworldcoordinates(-1, -0.3, 3, 1.3)
  42
  43     red = ColorTurtle(0, .5)
  44     green = ColorTurtle(1, .5)
  45     blue = ColorTurtle(2, .5)
  46     setbgcolor()
  47
  48     writer = Turtle()
  49     writer.ht()
  50     writer.pu()
  51     writer.goto(1,1.15)
  52     writer.write("DRAG!",align="center",font=("Arial",30,("bold","italic")))
  53     return "EVENTLOOP"
  54
  55 if __name__ == "__main__":
  56     msg = main()
  57     print msg
  58     mainloop()