<?php
error_reporting( ~E_NOTICE );
class myIso {
    private $blocks = array();
    private $maxcoords = array( 8, 8, 4, 'x' => 8, 'y' => 8, 'z' => 4 );
    public function __construct( $x = 8, $y = 8, $z = 4 ) {
        $this->maxcoords = array( $x, $y, $z, 'x' => $x, 'y' => $y, 'z' => $z );
    }
    public function addBlock( $block, $x, $y, $z ) {
        $this->blocks[$x][$y][$z] = $block;
    }

    public function flush( ) {
        $image = imagecreatetruecolor(512,512);
        $rendertable = array();

        for( $xy = $this->maxcoords['x']; $xy>=0; $xy-- ) {
            for( $z = $this->maxcoords['z']; $z>=0; $z-- ) {
                for( $xy2 = $xy; $xy2>=0; $xy2-- ) {
                    $myBlock  = $this->blocks[$xy][$xy2][$z];
                    $myBlock2 = $this->blocks[$xy2][$xy][$z];
                    if(isset($myBlock)) {
                        $sides = 0;
                        if( !isset($this->blocks[$xy][$xy2-1][$z]) ) { $sides += 1; }
                        if( !isset($this->blocks[$xy-1][$xy2][$z]) ) { $sides += 2; }
                        if( !isset($this->blocks[$xy][$xy2][$z+1]) ) { $sides += 4; }
                        if( $sides != 0 ) { $rendertable[] = array( $sides, $myBlock, $xy, $xy2, $z ); }
                    }
                    if(isset($myBlock2)) {
                        $sides = 0;
                        if( !isset($this->blocks[$xy2][$xy-1][$z]) ) { $sides += 1; }
                        if( !isset($this->blocks[$xy2-1][$xy][$z]) ) { $sides += 2; }
                        if( !isset($this->blocks[$xy2][$xy][$z+1]) ) { $sides += 4; }
                        if( $sides != 0 ) { $rendertable[] = array( $sides, $myBlock2, $xy2, $xy, $z  ); }
                    }
                }
            }
        }
        imagealphablending( $image , true );
        imagesavealpha( $image , true );
        $stone = array( imagecreatefrompng( "bloki/stone_t.png" ), imagecreatefrompng( "bloki/stone_l.png" ), imagecreatefrompng( "bloki/stone_r.png" ) );
        foreach( $stone as $v ) { imagealphablending( $v , true ); imagesavealpha( $v , true ); }
        //bool imagecopyresampled ( resource $dst_image , resource $src_image , int $dst_x , int $dst_y , int $src_x , int $src_y , int $dst_w , int $dst_h , int $src_w , int $src_h )

        $tan30 = abs(tan(30));
        $color = imagecolorallocate($image, 220, 245, 255);
        imagefilledrectangle ( $image , 2, 2, 510, 510, $color );

        foreach( $rendertable as $k => $v ) {
            if( $v[1] == "stone" ) { $tileset = $stone; }
            $sides = $v[0];
            while( $sides > 0 ) {
                if( $sides - 4 >= 0 ) {
                $sides -= 4;
                $tile = $tileset[0];
                $dst_x = 255 + $v[2]*22 - $v[3]*22;
                $dst_y = 500 - $v[4]*44 - 11 + $v[2]*11 - $v[3]*11;
                imagecopymerge( $image, $tile, $dst_x, $dst_y, 0, 0, 44, 22, 50 );
            }elseif( $sides - 2 >= 0 ) {
                $sides -= 2;
                $tile = $tileset[1];
                $dst_x = 255 + $v[2]*22 - $v[3]*22;
                $dst_y = 500 - $v[4]*44 + $v[2]*11 - $v[3]*11;
                imagecopymerge( $image, $tile, $dst_x, $dst_y, 0, 0, 23, 34, 70 );
            }elseif( $sides - 1 >= 0 ) {
                $sides -= 1;
                $tile = $tileset[2];
                $dst_x = 255 + $v[2]*22 - $v[3]*22 + 22;
                $dst_y = 500 - $v[4]*44 + $v[2]*11 - $v[3]*11;
                imagecopymerge( $image, $tile, $dst_x, $dst_y, 0, 0, 23, 34, 70 );
            }

            }
        }

        header('Content-Type: image/png');
        imagepng($image, null, 9);
        imagedestroy($image);
    }
}
$engine = new myIso();
$engine->addBlock( 'stone', 0, 1, 1 );
$engine->addBlock( 'stone', 0, 2, 2 );
$engine->addBlock( 'stone', 0, 2, 1 );
$engine->addBlock( 'stone', 0, 3, 1 );
$engine->flush();
?>