code: public Vector4f smoothStep(Vector4fc v, float t, Vector4f dest) {
          float t2 = t * t;
          float t3 = t2 * t;
          dest.x = (x + x - v.x() - v.x()) * t3 + (3.0f * v.x() - 3.0f * x) * t2 + x * t + x;
          dest.y = (y + y - v.y() - v.y()) * t3 + (3.0f * v.y() - 3.0f * y) * t2 + y * t + y;
          dest.z = (z + z - v.z() - v.z()) * t3 + (3.0f * v.z() - 3.0f * z) * t2 + z * t + z;
          dest.w = (w + w - v.w() - v.w()) * t3 + (3.0f * v.w() - 3.0f * w) * t2 + w * t + w;
          return dest;
      }
docs: /* (non-Javadoc)
  @see org.joml.Vector4fc#smoothStep(org.joml.Vector4fc, float, org.joml.Vector4f)