f',

				// called when the resource is loaded
				( gltf ) => {

					// put the model to the scene
					scene.add( gltf.scene );
					console.log( gltf );

					currentGltf = gltf;

				},

				// called while loading is progressing
				( progress ) => console.log( 'Loading model...', 100.0 * ( progress.loaded / progress.total ), '%' ),

				// called when loading has errors
				( error ) => console.error( error )

			);

			// helpers
			const gridHelper = new THREE.GridHelper( 10, 10 );
			scene.add( gr