如何计算两架飞机之间的角度？

Question

我有两架飞机,我怎么能计算它们之间的角度？是否也可以像平面一样计算两个Object3D点之间的角度？

下面是一个例子:https://jsfiddle.net/rsu842v8/1/

  const scene = new THREE.Scene();
  const camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 1, 1000);
  camera.position.set(25, 25, 12);

  var material = new THREE.MeshBasicMaterial({
    color: 0x00fff0,
    side: THREE.DoubleSide
  });
  window.plane1 = new THREE.Mesh(new THREE.PlaneGeometry(10, 10), material);
  scene.add(plane1);

  plane1.position.set(0.3, 1, -2);
  plane1.rotation.set(Math.PI / 3, Math.PI / 2, 1);

  window.plane2 = new THREE.Mesh(new THREE.PlaneGeometry(10, 10), new THREE.MeshBasicMaterial({
    color: 0x0fff00,
    side: THREE.DoubleSide
  }));
  scene.add(plane2);


  // setup rest
  var pointLight = new THREE.PointLight(0xFFFFFF);
  pointLight.position.x = 10;
  pointLight.position.y = 50;
  pointLight.position.z = 130;
  scene.add(pointLight)

  const renderer = new THREE.WebGLRenderer({
    antialias: true
  });
  renderer.setSize(window.innerWidth, window.innerHeight);
  renderer.setClearColor(0x20252f);
  renderer.setPixelRatio(window.devicePixelRatio);
  document.body.appendChild(renderer.domElement);

  const controls = new THREE.OrbitControls(camera, renderer.domElement);

  animate();

  // TODO: What is the angle between plane1 and plane2?

  function animate() {
    requestAnimationFrame(animate);
    render();
  }

  function render() {
    renderer.render(scene, camera);
  }

<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/r82/three.js"></script>
<script src="https://yume.human-interactive.org/examples/buffer-geometry/OrbitControls.js"></script>

Answer 1

你想找到两个three.js平面网格之间的角度.

未旋转,a THREE.PlaneGeometry面向正z轴.因此,平面的法线指向正z轴方向.

因此,创建一个(0,0,1)向量,并将相同的旋转应用于平面网格.

请注意,plane.quaternion设置时会自动更新plane.rotation,因此您可以在计算中使用四元数 - 如下所示:

var vec1 = new THREE.Vector3( 0, 0, 1 ); // create once and reuse
var vec2 = new THREE.Vector3( 0, 0, 1 );

vec1.applyQuaternion( plane1.quaternion );
vec2.applyQuaternion( plane2.quaternion );

var angle = vec1.angleTo( vec2 ); // radians

如果飞机是其他旋转物体的子物,则问题会复杂一些.

当然,您可以angleTo()用来查找任意两个向量之间的角度.

three.js r.86