This corresponds to a <SwitchCondition> entry within a group. It indicates the condition at which a level-of-detail is switched in or out. This is actually an abstract base class for potentially any number of specific different kinds of switching conditions; presently, only a <Distance> type is actually supported.
virtual void write(std::ostream &out, int indent_level) const = 0
- virtual void write(std::ostream &out, int indent_level) const = 0