spiral

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spiral.cs

Vector3 Spiral(int n)
{
  float k = Mathf.Ceil((Mathf.Sqrt(n) — 1.0f) / 2.0f);
  float t = 2.0f * k;
  float m = (t + 1f) * (t + 1f);
  if (n >= m — t)
  {
    return new Vector3(k — (m — n), 0f, -k);
  }
  else
  {
    m = m — t;
  }

  if (n >= m — t)
  {
    return new Vector3(-k, 0f, -k + (m — n));
  }
  else
  {
    m = m — t;
  }

  if (n >= m — t)
  {
    return new Vector3(-k + (m-n), 0f, k);
  }
  else
  {
    return new Vector3(k, 0f, k — (m — n — t));
  }
}