[Edu-sig] graphics programming with Python

Daniel Yoo dyoo@hkn.eecs.berkeley.edu
Wed, 9 May 2001 03:16:29 -0700 (PDT) 

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Here's a preliminary version of a simplified interface to a Tkinter
canvas.  It's simple enough so that the user just needs to type:

###
from graphics import *

def drawBox(x1, y1, x2, y2):
    """Draws a box where the upper left is (x1, y1), and the
    lower right is (x2, y2)."""
    positionPen(x1, y1)
    drawLineTo(x2, y1)
    drawLineTo(x2, y2)
    drawLineTo(x1, y2)
    drawLineTo(x1, y1)

drawBox(-100, 100, 100, -100)
###

to get a box drawn.  By default, the Canvas is 400x400, and the user can
send commands like:

    drawLine
    drawPoint
    setRGBColor

without having to worry about creating a canvas.  Also, it uses normal
rectangular coordinates, so (0, 0) is at the center, (200, 200) is the
upper right corner, and (-200, -200) is the bottom left.

Please give suggestions on this; I just typed this up yesterday, so it
surely has room for improvement and clarity.

I hope this is useful!

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