javascript-围绕球体的对象的三个js旋转

我正在使用粒子系统在球体上均匀分布点.效果很好.
然后,在这些点上放置给定几何的实例.这部分也可以.
我现在想旋转这些几何形状以匹配球体的表面角度.

这是到目前为止的功能:

function placeGeometryAtPlatonicPoints (points) {
  var len = points.length -1,
    x, y, z,
    geometry,
    // subgroup a group to apply the rotations to
    subgroup = new THREE.Object3D(),
    mesh,
    material = new THREE.MeshLambertMaterial({
      color: 0x0992299
    }),
    r,
    theta,
    varphi;

  // I wait to append this group because I am waiting for the 
  // particles to settle into there positions
  scene.add(group);

  for (len; len >= 0; len -= 1) {
    // Geometry could be any geometry I am just using a cube to test.
    geometry = new THREE.CubeGeometry( 25, 25, 25, 1, 1, 1 );
    x = points[len].x;
    y = points[len].y;
    z = points[len].z;

    // Move the geometry to the point on the sphere. 
    geometry.applyMatrix( new THREE.Matrix4().makeTranslation(x, y, z) );

    mesh = new THREE.Mesh( geometry, material );
    subgroup.add(mesh);

    // This next portion is just some guess work about 
    // polar and azimuth coordinates
    r = Math.sqrt(Math.pow(x,2) + Math.pow(y,2) + Math.pow(z,2));
    theta = Math.acos(z/r);
    varphi = Math.atan(y/x);

    theta = theta * (180/Math.PI);
    varphi = varphi * (180/Math.PI);

    console.log({
      theta : theta,
      varphi : varphi
    });

    // This would be the implementation of the rotation degrees.
    subgroup.rotation.x = 0;
    subgroup.rotation.y = 0;
    subgroup.rotation.z = 0;

    group.add(subgroup);
  }
}

我是Three js的新手,所以如果有更好的方法来完成所有这些工作,请告诉我.这是我的WIP.在渲染几何图形之前,您必须先给它一秒钟以正确放置粒子.我可以加快速度,但是我喜欢动画:)

解决方法:

如果希望旋转多维数据集以使其与球体相切,则可以将每个多维数据集都视为位于棒的末端.

棒是位于原点的Object3D.多维数据集是位于(0,0,r)的棍子的子元素.现在将操纵杆旋转到所需位置. (但要避免北极和南极.)

var parent = new THREE.Object3D();
scene.add( parent );

var stick = new THREE.Object3D();
var point = new THREE.Vector3( x, y, z );
stick.lookAt( point );
parent.add( stick );

var geometry = new THREE.CubeGeometry( 25, 25, 25, 1, 1, 1 );
var mesh = new THREE.Mesh( geometry, material );
mesh.position.set( 0, 0, r );
stick.add( mesh );

three.js r.64

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