scale method

void scale (double scale)

Scales this by scale.

Implementation 

void scale(double scale) {
  _qStorage[3] = _qStorage[3] * scale;
  _qStorage[2] = _qStorage[2] * scale;
  _qStorage[1] = _qStorage[1] * scale;
  _qStorage[0] = _qStorage[0] * scale;
}