The turtle module provides turtle graphics primitives, in both an
object-oriented and procedure-oriented ways. Because it uses Tkinter
for the underlying graphics, it needs a version of python installed with
Tk support.
The procedural interface uses a pen and a canvas which are automagically
created when any of the functions are called.
The turtle module defines the following functions:
degrees(
)
Set angle measurement units to degrees.
radians(
)
Set angle measurement units to radians.
reset(
)
Clear the screen, re-center the pen, and set variables to the default
values.
clear(
)
Clear the screen.
tracer(
flag)
Set tracing on/off (according to whether flag is true or not). Tracing
means line are drawn more slowly, with an animation of an arrow along the
line.
forward(
distance)
Go forward distance steps.
backward(
distance)
Go backward distance steps.
left(
angle)
Turn left angle units. Units are by default degrees, but can be
set via the degrees() and radians() functions.
right(
angle)
Turn right angle units. Units are by default degrees, but can be
set via the degrees() and radians() functions.
up(
)
Move the pen up -- stop drawing.
down(
)
Move the pen down -- draw when moving.
width(
width)
Set the line width to width.
color(
s)
color(
(r, g, b))
color(
r, g, b)
Set the pen color. In the first form, the color is specified as a
Tk color specification as a string. The second form specifies the
color as a tuple of the RGB values, each in the range [0..1]. For the
third form, the color is specified giving the RGB values as three
separate parameters (each in the range [0..1]).
write(
text[, move])
Write text at the current pen position. If move is true,
the pen is moved to the bottom-right corner of the text. By default,
move is false.
fill(
flag)
The complete specifications are rather complex, but the recommended
usage is: call fill(1) before drawing a path you want to fill,
and call fill(0) when you finish to draw the path.
circle(
radius[, extent])
Draw a circle with radius radius whose center-point is
radius units left of the turtle.
extent determines which part of a circle is drawn: if
not given it defaults to a full circle.
If extent is not a full circle, one endpoint of the arc is the
current pen position. The arc is drawn in a counter clockwise
direction if radius is positive, otherwise in a clockwise
direction. In the process, the direction of the turtle is changed
by the amount of the extent.
goto(
x, y)
goto(
(x, y))
Go to co-ordinates x, y. The co-ordinates may be
specified either as two separate arguments or as a 2-tuple.
This module also does from math import *, so see the
documentation for the math module for additional constants
and functions useful for turtle graphics.
demo(
)
Exercise the module a bit.
exceptionError
Exception raised on any error caught by this module.
For examples, see the code of the demo() function.
This module defines the following classes:
classPen(
)
Define a pen. All above functions can be called as a methods on the given
pen. The constructor automatically creates a canvas do be drawn on.
classRawPen(
canvas)
Define a pen which draws on a canvas canvas. This is useful if
you want to use the module to create graphics in a ``real'' program.
