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                <?php  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                /** @formatter:off  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * ******************************************************************  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * Created by   Marko Kungla on Jun 20, 2016 - 9:01:22 PM  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * Contact      [email protected]  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * @copyright   2016 Marko Kungla - https://github.com/mkungla  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * @license     The MIT License (MIT)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 *   | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * @category       AframeVR  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * @package        aframe-php  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 *   | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * Lang         PHP (php version >= 7)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * Encoding     UTF-8  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * File         Scene.php  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * Code format  PSR-2 and 12  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * @link        https://github.com/mkungla/aframe-php  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 ^ @issues      https://github.com/mkungla/aframe-php/issues  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * ********************************************************************  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * Contributors:  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * @author Marko Kungla <[email protected]>  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * ********************************************************************  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * Comments:  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * @formatter:on */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                namespace AframeVR\Core;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                use \AframeVR\Core\Helpers\MetaTags;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                use \AframeVR\Extras\Primitives;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                use \DOMImplementation;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                use \DOMDocument;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                use \AframeVR\Core\Entity;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                use \AframeVR\Interfaces\AssetsInterface;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                final class Scene  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    use Primitives;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    private $name;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    protected $assets = array();  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * A-Frame scene entities  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @var array|null $entities  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    protected $entities;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    public function __construct($name)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        $this->name = $name;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * Scene DOMDocument meta tags object  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @return \AframeVR\Core\Helpers\MetaTags  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                             7                          | 
                
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                    public function meta()  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        return $this->meta ?? $this->meta = new MetaTags();  | 
            
                            
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                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * Entity  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param string $name              | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @return Entity  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    public function entity(string $name = 'untitled'): Entity  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        return $this->entities[$name] ?? $this->entities[$name] = new Entity();  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * Assets  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param string $name              | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @return AssetsnInterface  | 
            
                            
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                     */  | 
            
            
                                                                        
                            
            
                                    
            
            
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                    public function assets(string $name = 'untitled'): AssetsInterface  | 
            
            
                                                                        
                            
            
                                    
            
            
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                    { | 
            
            
                                                                        
                            
            
                                    
            
            
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                        return $this->assets[$name] ?? $this->assets[$name] = new Assets();  | 
            
            
                                                                        
                            
            
                                    
            
            
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                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * Render the A-Frame scene  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param bool $full              | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param bool $print              | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    public function render($full = true, $print = true)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        $dom = new DOMImplementation();  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        $doctype = $dom->createDocumentType('html'); | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        $aframe_dom = $dom->createDocument(null, 'html', $doctype);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        $aframe_dom_head = $aframe_dom->createElement('head'); | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        $aframe_dom_body = $aframe_dom->createElement('body', "\n"); | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        $aframe_dom_scene = $aframe_dom->createElement("a-scene", "\n"); | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        /* Add metatags */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        $this->meta()->DOMAppendTags($aframe_dom, $aframe_dom_head);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        /* Add primitives to DOM */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        $this->DOMAppendPrimitives($aframe_dom, $aframe_dom_scene);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        /* Add entities */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                             6                          | 
                
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                        if (is_array($this->entities)) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            foreach ($this->entities as $entity) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                                $entity_dom = $entity->DOMElement($aframe_dom);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                                $aframe_dom_scene->appendChild($entity_dom);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                             6                          | 
                
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                        $cdn_script = $aframe_dom->createElement('script'); | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                             6                          | 
                
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                        $cdn_script->setAttribute('src', 'https://aframe.io/releases/0.2.0/aframe.min.js'); | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                             6                          | 
                
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                        $aframe_dom_head->appendChild($cdn_script);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        /* Pull DOM together */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                             6                          | 
                
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                        $aframe_dom_body->appendChild($aframe_dom_scene);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                             6                          | 
                
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                        $html = $aframe_dom->getElementsByTagName('html')[0]; | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                             6                          | 
                
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                        $html->appendChild($aframe_dom_head);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                             6                          | 
                
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                        $html->appendChild($aframe_dom_body);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                             6                          | 
                
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                        $aframe_dom->formatOutput = true;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                          | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        /* Print Scene */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                          | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                             6                          | 
                
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                        if (! $full) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                             1                          | 
                
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                            $html = new DOMDocument();  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                             1                          | 
                
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                            $html_scene = $html->importNode($aframe_dom_scene, true);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                             1                          | 
                
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                            $html->appendChild($html_scene);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                             1                          | 
                
                 | 
                            if ($print)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    133
                 | 
                                    
                             1                          | 
                
                 | 
                                print $html->saveHTML();  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    134
                 | 
                                    
                                                     | 
                
                 | 
                            else  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    135
                 | 
                                    
                             1                          | 
                
                 | 
                                return $html->saveHTML();  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    136
                 | 
                                    
                                                     | 
                
                 | 
                        } else { | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    137
                 | 
                                    
                             6                          | 
                
                 | 
                            if ($print)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    138
                 | 
                                    
                             1                          | 
                
                 | 
                                print $aframe_dom->saveHTML();  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    139
                 | 
                                    
                                                     | 
                
                 | 
                            else  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    140
                 | 
                                    
                             6                          | 
                
                 | 
                                return $aframe_dom->saveHTML();  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    141
                 | 
                                    
                                                     | 
                
                 | 
                        }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    142
                 | 
                                    
                             1                          | 
                
                 | 
                    }  | 
            
            
                                                                                                            
                                                                
            
                                    
            
            
                | 
                    143
                 | 
                                    
                                                     | 
                
                 | 
                }  | 
            
            
                                                        
            
                                    
            
            
                | 
                    144
                 | 
                                    
                                                     | 
                
                 | 
                   | 
            
            
                        
In PHP it is possible to write to properties without declaring them. For example, the following is perfectly valid PHP code:
Generally, it is a good practice to explictly declare properties to avoid accidental typos and provide IDE auto-completion: