define PICKING\n" + vert,
				fragmentShader: "#define PICKING\n" + frag,
				uniforms: {
					pickingColor: {
						value: new THREE.Color()
					}
				}
			} );

			// geometry / mesh

			var matrix = new THREE.Matrix4();

			for ( var i = 0; i < instanceCount; i ++ ) {

				var object = new THREE.Mesh( geo, material );
				objectCount ++;
				randomizeMatrix( matrix );
				object.applyMatrix( matrix );
				var pickingObject = object.clone();
				objectCount ++;

				object.material = material.clone();
		