     render();
    }

    function render() {
        position = ((new Date().getTime() - start_time) * 0.03) % 8000;
        camera.position.x += (mouseX - camera.target.position.x) * 0.01;
        camera.position.y += (-mouseY - camera.target.position.y) * 0.01;
        camera.position.z = -position + 8000;
        camera.target.position.x = camera.position.x;
        camera.target.position.y = camera.position.y;
        camera.target.position.z = camera.position.z - 1000;
        renderer.render(scene, c