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package
Turtle;
# Written by jreed@itis.com, adapted by Cristy.
sub new
{
my $class = shift;
my $self = {};
@{$self}{qw(x y theta mirror)} = @_;
bless $self, $class;
}
sub forward
{
my $self = shift;
my ($r, $what) = @_;
my ($newx, $newy)=($self->{x}+$r* sin($self->{theta}),
$self->{y}+$r*-cos($self->{theta}));
if ($what) {
&$what($self->{x}, $self->{y}, $newx, $newy); # motion
}
# According to the coderef passed in
($self->{x}, $self->{y})=($newx, $newy); # change the old coords
}
sub turn
{
my $self = shift;
my $dtheta = shift;
$self->{theta} += $dtheta*$self->{mirror};
}
sub state
{
my $self = shift;
@{$self}{qw(x y theta mirror)};
}
sub setstate
{
my $self = shift;
@{$self}{qw(x y theta mirror)} = @_;
}
sub mirror
{
my $self = shift;
$self->{mirror} *= -1;
}
"Turtle.pm";
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