sh);
    object.planeMesh = planeMesh;

    object.plane = new THREE.Plane();
    object.leftLine = new THREE.Line3();
    object.topLine = new THREE.Line3();
    object.update = () => {
      object.leftLine.start
        .set(-1/2, keyboardHeight / keyboardWidth / 2, 0)
        .applyMatrix4(planeMesh.matrixWorld);
      object.leftLine.end
        .set(-1/2, -keyboardHeight / keyboardWidth / 2, 0)
        .applyMatrix4(planeMesh.matrixWorld);

      object.topLine.start
        .set(-1/2, keyboardHeight 