Function getSphereAttributes

docs/tests/v2/es6/js/sanddance.js:32247–32319

(nlat, nlong, radius)

exports.default = SphereGeometry;

function getSphereAttributes(nlat, nlong, radius) {
  var startLat = 0;
  var endLat = Math.PI;
  var latRange = endLat - startLat;
  var startLong = 0;
  var endLong = 2 * Math.PI;
  var longRange = endLong - startLong;
  var numVertices = (nlat + 1) * (nlong + 1);

  if (typeof radius === 'number') {
    var value = radius;

    radius = function radius(n1, n2, n3, u, v) {
      return value;
    };
  }

  var positions = new Float32Array(numVertices * 3);
  var normals = new Float32Array(numVertices * 3);
  var texCoords = new Float32Array(numVertices * 2);
  var indices = new Uint16Array(nlat * nlong * 6); // Create positions, normals and texCoords

  for (var y = 0; y <= nlat; y++) {
    for (var x = 0; x <= nlong; x++) {
      var u = x / nlong;
      var v = y / nlat;
      var index = x + y * (nlong + 1);
      var i2 = index * 2;
      var i3 = index * 3;
      var theta = longRange * u;
      var phi = latRange * v;
      var sinTheta = Math.sin(theta);
      var cosTheta = Math.cos(theta);
      var sinPhi = Math.sin(phi);
      var cosPhi = Math.cos(phi);
      var ux = cosTheta * sinPhi;
      var uy = cosPhi;
      var uz = sinTheta * sinPhi;
      var r = radius(ux, uy, uz, u, v);
      positions[i3 + 0] = r * ux;
      positions[i3 + 1] = r * uy;
      positions[i3 + 2] = r * uz;
      normals[i3 + 0] = ux;
      normals[i3 + 1] = uy;
      normals[i3 + 2] = uz;
      texCoords[i2 + 0] = u;
      texCoords[i2 + 1] = v;
    }
  } // Create indices


  var numVertsAround = nlat + 1;

  for (var _x = 0; _x < nlat; _x++) {
    for (var _y = 0; _y < nlong; _y++) {
      var _index = (_x * nlong + _y) * 6;

      indices[_index + 0] = _y * numVertsAround + _x;