setQuaternionFromProperEuler static method

void setQuaternionFromProperEuler(dynamic q, num a, num b, num c, String order,)

Implementation

static void setQuaternionFromProperEuler(
    q, num a, num b, num c, String order) {
  // Intrinsic Proper Euler Angles - see https://en.wikipedia.org/wiki/Euler_angles

  // rotations are applied to the axes in the order specified by 'order'
  // rotation by angle 'a' is applied first, then by angle 'b', then by angle 'c'
  // angles are in radians

  var cos = Math.cos;
  var sin = Math.sin;

  var c2 = cos(b / 2);
  var s2 = sin(b / 2);

  var c13 = cos((a + c) / 2);
  var s13 = sin((a + c) / 2);

  var c1_3 = cos((a - c) / 2);
  var s1_3 = sin((a - c) / 2);

  var c3_1 = cos((c - a) / 2);
  var s3_1 = sin((c - a) / 2);

  switch (order) {
    case 'XYX':
      q.set(c2 * s13, s2 * c1_3, s2 * s1_3, c2 * c13);
      break;

    case 'YZY':
      q.set(s2 * s1_3, c2 * s13, s2 * c1_3, c2 * c13);
      break;

    case 'ZXZ':
      q.set(s2 * c1_3, s2 * s1_3, c2 * s13, c2 * c13);
      break;

    case 'XZX':
      q.set(c2 * s13, s2 * s3_1, s2 * c3_1, c2 * c13);
      break;

    case 'YXY':
      q.set(s2 * c3_1, c2 * s13, s2 * s3_1, c2 * c13);
      break;

    case 'ZYZ':
      q.set(s2 * s3_1, s2 * c3_1, c2 * s13, c2 * c13);
      break;

    default:
      print(
          'THREE.MathUtils: .setQuaternionFromProperEuler() encountered an unknown order: ' +
              order);
  }
}