在 Autodesk Forge 中围绕模型旋转相机

Question

我创建了一个扩展程序，可以围绕上传到制作的存储桶中的 Revit 模型旋转相机，但是在单击工具栏中的按钮后，如何让相机不断地围绕模型旋转。另外，如何再次单击相同的按钮来停止旋转？下面的代码是我用来在单击按钮后旋转相机的代码。

var _this = this;
var _viewer = _this.viewer;
var turnTableToolbarButton = new Autodesk.Viewing.UI.Button('turnTableButton');
turnTableToolbarButton.onClick = function (e) { 

    const nav = _viewer.navigation;
    const up = nav.getCameraUpVector();
    var pos = nav.getPosition();
    const axis = new THREE.Vector3(0, 0, 1);
    const speed = 10.0 * Math.PI / 180;

    const matrix = new THREE.Matrix4().makeRotationAxis(axis, speed * 0.1);

    pos.applyMatrix4(matrix);
    up.applyMatrix4(matrix);

    nav.setView(pos, new THREE.Vector3(0, 0, 0));
    nav.setCameraUpVector(up);
    var viewState = _viewer.getState();
    _viewer.restoreState(viewState);
};

Answer 1

我认为您在这里需要的是使用 requestAnimation，您的按钮停止或启动对新帧的请求：

  let started = false;

  let rotateCamera = () => {
      if (started) {
          requestAnimationFrame(rotateCamera);
      }

      const nav = viewer.navigation;
      const up = nav.getCameraUpVector();
      const axis = new THREE.Vector3(0, 0, 1);
      const speed = 10.0 * Math.PI / 180;
      const matrix = new THREE.Matrix4().makeRotationAxis(axis, speed * 0.1);

      let pos = nav.getPosition();
      pos.applyMatrix4(matrix);
      up.applyMatrix4(matrix);
      nav.setView(pos, new THREE.Vector3(0, 0, 0));
      nav.setCameraUpVector(up);
      var viewState = viewer.getState();
      // viewer.restoreState(viewState);

  };

  turnTableToolbarButton.onClick = function (e) {
      started = !started;
      if (started) rotateCamera()
  };

查看my repo of extensions 以获取基于您的 sn-p 和现场插图的完整代码。