setRandom method Null safety

void setRandom(
  1. Random rn
)

Set the quaternion to a random rotation. The random number generator rn is used to generate the random numbers for the rotation.

Implementation

void setRandom(math.Random rn) {
  // From: "Uniform Random Rotations", Ken Shoemake, Graphics Gems III,
  // pg. 124-132.
  final x0 = rn.nextDouble();
  final r1 = math.sqrt(1.0 - x0);
  final r2 = math.sqrt(x0);
  final t1 = math.pi * 2.0 * rn.nextDouble();
  final t2 = math.pi * 2.0 * rn.nextDouble();
  final c1 = math.cos(t1);
  final s1 = math.sin(t1);
  final c2 = math.cos(t2);
  final s2 = math.sin(t2);
  _qStorage[0] = s1 * r1;
  _qStorage[1] = c1 * r1;
  _qStorage[2] = s2 * r2;
  _qStorage[3] = c2 * r2;
}