[Tutor] full screen turtle.py

[reavey]

Re: [Tutor] full screen turtle.py    add this thread to my home page
by Gregor Lingl other posts by this author
Feb 11 2003 10:38PM messages near this date
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reavey schrieb:

 > is there a way to display a full screen when turtle.py initializes?

As a default-canvas is created the first time when you call an arbitrary
turtle-graphics
function, there is no way to pass information about its size to the canvas.

But:

(1) There is the possibility to create turtle-objects on your own
Tkinter-Canvas
which may have any size you want. more precisely, you have to create
an object of the RawPen class, which goes like this:

  >>> from Tkinter import Canvas
  >>> cv = Canvas(width=800, height=600)
  >>> cv.pack()
  >>> t = RawPen(cv)
  >>> t.forward(100)

you may reset the size of cv with something like:

  >>> cv["width"]=400
  >>> cv["height"] = 500

and recenter t by calling t.reset  (which works essentially the same way
you used when resizing the default-canvas manually)

(2) Another way to accomplish what you want ist do decide to rewrite
the reset-function of the turtle-module in order to pass information
about the size of the canvas. (If these arguments are not given, it
works the old way):

First you have to change the reset-method of RawPen  (approx line 40):

     def reset(self, width = None, height = None):
         canvas = self._canvas
         if width: canvas["width"] = width
         if height: canvas["height"] = height
         self._canvas.update()
         # .... and so on. as before

Then you have to modify the reset - function (approx line 350):

def reset(width=None, height=None): _getpen().reset(width,height)

I've attached a modified turtle.py

With these changes the following will be possible:

  >>> from turtle import *
  >>> reset(800,600)
  >>> forward(50)
  >>> reset(200,200)

Regards, Gregor

P.S. I didn't extensively test these changes, so maybe there will be
some unwanted side-effects, especially when using RawPen.
Maybe I'll have a look at this sometimes later ...

 >
 > The first canvas takes up a small portion of the display (around 10%).
 > When I hit the expand button on the canvas it doesn't recenter.
 > The drawing still uses the inititial canvas coordinates.
 >
 > btw: this is not a problem using the interactive interpreter as a
 > turtle.reset()
 >        issued after you expand works as expected.
 >
 > thanks
 > re-v


I have tried part two being the better solution.
I get the following error
traceback(most recent call last)
file "<stdin>",line 1 in?
############## the reader of this message will please from this point on 
replace the word file with File 
"usr/lib/python2.2/lib-tk/turtle.py#################

file line 314, in reset
def reset(width=None,height=None)::_getpen().reset(height,width)

file line 308 in_getpen_pen=pen=Pen()

file line 292, in__init__RawPen.__init__(self._canvas)

file line 16, in__init__self.reset()

file line 34 , in reset self._origin = float(width)/2.0,float(height)/2.0

type error: float() needs a strong argument

from turtle import *    ####works
reset()  ###produces the above failure
reset(200,200) ####error as above
reset("200","200") ###error as above

Thanks
re-v