docs: public void expand(final BoundingBox rhs) {
          if (rhs != null && rhs != this) {
              mVertices = appendArrays(mVertices, rhs.mVertices);
              mMinCorner.min(rhs.mMinCorner);
              mMaxCorner.max(rhs.mMaxCorner);
  
              Vector3f temp = new Vector3f(mMinCorner);
              mCenter = new Vector3f(mMinCorner.x + (mMaxCorner.x - mMinCorner.x) * .5f,
                      mMinCorner.y + (mMaxCorner.y - mMinCorner.y) * .5f,
                      mMinCorner.z + (mMaxCorner.z - mMinCorner.z) * .5f);
              temp.set(mMaxCorner);
              mRadius = temp.sub(mMinCorner).length() * .5f;
          }
      }