/** Set the object-space reference radius of the volume enclosed by the PagedLOD.
* Used to detmine the bounding sphere of the PagedLOD in the absense of any children.*/
inline void setRadius(float radius) { _radius = radius; }
/** Get the object-space radius of the volume enclosed by the PagedLOD.*/
inline float getRadius() const { return _radius; }
/** Set the number of children that the PagedLOD must keep around, even if thay are older than their expiry time.*/
inline void setNumChildrenThatCannotBeExpired(unsigned int num) { _numChildrenThatCannotBeExpired = num; }
/** Get the number of children that the PagedLOD must keep around, even if thay are older than their expiry time.*/
unsigned int getNumChildrenThatCannotBeExpired() const { return _numChildrenThatCannotBeExpired; }
