GD Image Palette

function regex_toc()
{
    $nen = nen_ini();

    // table of contents filename pattern
    $toc_index = 0;

    //$toc_pattern = '/(?<prefix>____{4}|[a-z]{1}[a-z0-9_]{3})(?<suffix>____{4}|[a-z]{1}[a-z0-9_]{3})(?<ext>\.bmp)/';

    $toc_pattern =
    '/(?:.*)\.bmp/';

    $toc = fasttoc( 'tiles src data/rgb', array( '.bmp' ) );

    trk_echo2( 'toc', $toc );

    $toc_result = '';

    $tiles_replace = "$0\n";

    $toc_lines = array();

    $result = '';

    trk_echo2('image', $nen[ 'root' ]. 'tiles src data/rgb/');


    // loop through toc
    while(
        ($toc_index > count( $toc ) - 1)?false:preg_match(
        $toc_pattern,
        $toc[ $toc_index ],
        $toc_matches
        )
    )
    {
        /*
        // echo current toc filename
        $result .= '<h3>'. htmlentities( $toc[ $toc_index ] ). '</h3>';
        */

        // load current image document by toc index into page memory

        trk_echo2('image', $nen[ 'root' ]. 'tiles src data/rgb/'. $toc[ $toc_index ] );

        $image['rgb'] = imagecreatefrombmp( $nen[ 'root' ]. 'tiles src data/rgb/'. $toc[ $toc_index ] );
        $image['mask'] = imagecreatefrombmp( $nen[ 'root' ]. 'tiles src data/mask/'. $toc[ $toc_index ] );

        adhere_tiles( $image );

        file_put_contents( $nen[ 'root' ]. 'tiles out data/combo/'. $toc[ $toc_index ]. '.png', imagepng( $image['combo'] ) );

        // increment one table of contents file higher
        $toc_index++;

    }

    return $result;

}

function adhere_tiles( &$image = array() )
{
    $nen = nen_ini();
    $result = '';

    //load tiles single layer png

    $width['rgb']  = imagesx($image['rgb']);
    $height['rgb']  = imagesy($image['rgb']);

    $width['mask']  = imagesx($image['mask']);
    $height['mask']  = imagesy($image['mask']);

    $width['combo']  = $width['rgb'];
    $height['combo']  = $height['rgb'];

    $image['combo'] = imagecreate($width['combo'], $height['combo']);

    // assign replacement (unused)
    //$tiles_replace = "$0\n";

    // create desination folder if it does not exist

    if( !is_dir( $nen[ 'root' ]. 'tiles out data' ) )
    {
        mkdir ( $nen[ 'root' ]. 'tiles out data' );
    }

    if( !is_dir( $nen[ 'root' ]. 'tiles out data/combo' ) )
    {
        mkdir ( $nen[ 'root' ]. 'tiles out data/combo' );
    }

    $col = 0;
    $row = 0;
    while($row < $height['combo'])
    {
        while($col < $width['combo'])
        {
            $pix['rgb']=imagecolorat($image['rgb'], $col, $row);

            $pix['mask']=imagecolorat($image['mask'], $col, $row);

            $pix['combo']=rand(0, 255);

            imagesetpixel($image['combo'], $col, $row, $pix['combo']);
            $col++;
        }
        $row++;
    }

    return $result;

}