NAME
Data::Turtle - Turtle Movement and State Operations
VERSION
version 0.0202
SYNOPSIS
use Data::Turtle;
my $turtle = Data::Turtle->new;
$turtle->pen_up;
$turtle->right(45);
$turtle->forward(10);
$turtle->goto(100, 100);
$turtle->mirror;
$turtle->backward(10);
$turtle->pen_down;
my ($x, $y, $heading, $status, $color, $size) = $turtle->get_state;
$turtle->set_state($x, $y, $heading, $status, $color, $size);
for my $i (1 .. 4) {
my @line = $turtle->forward(50);
# if (@line) { ... # Draw it!
$turtle->right(90);
}
DESCRIPTION
This module enables basic turtle movement and state operations without requiring any particular graphics package.
The methods don't draw anything. They just set or output coordinates and values for drawing by your favorite graphics package.
For examples with GD and Imager, please see the files in the eg/ distribution directory.
METHODS
new
$turtle = Data::Turtle->new;
$turtle = Data::Turtle->new(
width => $width,
height => $height,
x => $x0,
y => $y0,
heading => $heading,
pen_status => $pen_status,
pen_color => $pen_color,
pen_size => $pen_size,
);
Return a Data::Turtle
object.
Attributes:
width, height
Drawing surface dimensions. Defaults:
width = 500 height = 500
x, y, heading
Coordinate parameters. Defaults:
x = width / 2 y = height / 2 heading = 270 (degrees)
pen_status, pen_color, pen_size
Is the pen is up or down? Default: 1 (down position)
Pen properties. Defaults: pen_color = the string 'black', pen_size = 1
home
$turtle->home;
Move the turtle cursor to the starting x,y position and heading.
pen_up
$turtle->pen_up;
Raise the pen head to stop drawing.
pen_down
$turtle->pen_down;
Lower the pen head to begin drawing.
right
$turtle->right($degrees);
Turn to the right.
left
$turtle->left($degrees);
Turn to the left.
position
@pos = $turtle->position;
Return the current pen position as a list of x and y.
get_state
@state = $turtle->get_state;
Return the following settings as a list:
x, y, heading, pen_status, pen_color, pen_size
set_state
$turtle->set_state( $x, $y, $heading, $pen_status, $pen_color, $pen_size );
Set the turtle state with the given parameters.
forward
@line = $turtle->forward($steps);
Move forward the given number of steps. If the pen is down, a list defining a line is returned with these values:
x0, y0, x, y, pen_color, pen_size
backward
@line = $turtle->backward($steps);
Move backward the given number of steps. If the pen is down, a list defining a line is returned with these values:
x0, y0, x, y, pen_color, pen_size
mirror
$turtle->mirror;
Reflect the heading (by multiplying by -1).
goto
@line = $turtle->goto($x, $y);
Move the pen to the given coordinate. If the pen is down, a list defining a line is returned with these values:
x0, y0, x, y, pen_color, pen_size
SEE ALSO
GD::Simple has built-in turtle graphics
https://metacpan.org/source/YVESP/llg-1.07/Turtle.pm
https://en.wikipedia.org/wiki/Turtle_graphics
AUTHOR
Gene Boggs <gene@cpan.org>
COPYRIGHT AND LICENSE
This software is copyright (c) 2015-2023 by Gene Boggs.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.