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Algorithm::BinPack::2D - efficiently pack items into rectangles


Algorithm::BinPack::2D efficiently packs items into bins. The bins are given a maximum width and height, and items are packed in with as little empty space as possible. An example use would be backing up small images to concatenated images, while minimizing the number of images required.

    my $bp = Algorithm::BinPack::2D->new(binwidth => 512, binheight => 512);

    $bp->add_item(label => "one.png",   width =>  30, height =>  10);
    $bp->add_item(label => "two.png",   width => 200, height =>  40);
    $bp->add_item(label => "three.png", width =>  30, height => 300);
    $bp->add_item(label => "four.png",  width => 400, height => 100);

    for ($bp->pack_bins) {
        print "Bin width: ", $_->{width}, " x ", $_->{height}, "\n";
        print "     Item: ", $_->{label}, "\n" for @{ $_->{items} };



Creates a new Algorithm::BinPack::2D object. The maximum bin width and height is specified as a named argument 'binwidth' and 'binheight', and is required.

    my $bp = Algorithm::BinPack::2D->new(binwidth => 512, binheight => 512);

Adds an item to be packed into a bin. Required named arguments are 'label', 'width' and 'height', but any others can be specified, and will be saved.

    $bp->add_item(label => 'one',  width => 1, height => 1);

Packs the items into bins. This method tries to leave as little empty space in each bin as possible. It returns a list of hashrefs with the key 'width' containing the total bin width, 'height' containing the total bin height, and 'items' containing an arrayref holding the items in the bin. Each item is in turn a hashref containing the keys 'label', 'x', 'y', 'width' and 'height'.

    for my $bin ($bp->pack_bins) {
        print "Bin width: ", $bin->{width}, " x ", $bin->{height}, "\n";

        for my $item (@{ $bin->{items} }) {
            printf "  %-6s %-20s\n", $_, $item->{$_} for keys %{ $item };
            print  "  ---\n";




Tasuku SUENAGA a.k.a. gunyarakun <tasuku-s-cpan ATAT>


Copyright (C) Tasuku SUENAGA a.k.a. gunyarakun

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.