view release on metacpan or  search on metacpan

lib/Algorithm/Easing/Cubic.pm  view on Meta::CPAN

package Algorithm::Easing::Cubic;

use Moose;

use Math::Trig qw(:pi);

use constant EPSILON => 0.000001;

extends 'Algorithm::Easing::Ease';

use namespace::autoclean;

sub ease_in  {
    my $self = shift;
    my ($t,$b,$c,$d) = (shift,shift,shift,shift);

    return $b if ($t < EPSILON);
    return $c if ($d < EPSILON);

    return $c * ($t /= $d) * $t * $t + $b;
}

sub ease_out  {
    my $self = shift;
    my ($t,$b,$c,$d) = (shift,shift,shift,shift);

    return $b if ($t < EPSILON);
    return $c if ($d < EPSILON);

    return $c * (($t = $t / $d - 1) * $t * $t + 1) + $b;
}

sub ease_both  {
    my $self = shift;
    my ($t,$b,$c,$d) = (shift,shift,shift,shift);

    return $b if ($t < EPSILON);
    return $c if ($d < EPSILON);

    if (($t /= $d/2) < 1) {
        return $c / 2 * $t * $t * $t + $b;
    }

    return $c / 2 * (($t -= 2) * $t * $t + 2) + $b;
}

1;

__END__

# MAN3 POD

=head1 NAME

Algorithm::Easing::Cubic - Calculate eased translations between two positive whole integer values over time

=cut

=head1 SYNOPSIS

        use Algorithm::Easing;
        use Algorithm::Easing::Ease;

        # this example produces traditional 'cubic' output;

        my $translation = Algorithm::Easing::Cubic->new;

        # total time for eased translation as a real positive integer value
        my $d = 2.5;

        # begin