code: public Quaternion randomize (Random rand) {
          // pick angles according to the surface area distribution
          return fromAngles(MathUtil.lerp(-Math.PI, +Math.PI, rand.nextFloat()),
                            Math.asin(MathUtil.lerp(-1f, +1f, rand.nextFloat())),
                            MathUtil.lerp(-Math.PI, +Math.PI, rand.nextFloat()));
      }
docs: Sets this to a random rotation obtained from a completely uniform distribution.