processScene( scene ) {

    		const json = this.json;
    		const options = this.options;

    		if ( ! json.scenes ) {

    			json.scenes = [];
    			json.scene = 0;

    		}

    		const sceneDef = {};

    		if ( scene.name !== '' ) sceneDef.name = scene.name;

    		json.scenes.push( sceneDef );

    		const nodes = [];

    		for ( let i = 0, l = scene.children.length; i < l; i ++ ) {

    			const child = scene.children[ i ];

    			if ( child.visible || options.onlyVisible === false ) {

    				const nodeIndex = this.processNode( child );

    				if ( nodeIndex !== null ) nodes.push( nodeIndex );

    			}

    		}

    		if ( nodes.length > 0 ) sceneDef.nodes = nodes;

    		this.serializeUserData( scene, sceneDef );

    	}
Process Scene
@param  {Scene} node Scene to process