native UnitPoolAddUnitType takes unitpool whichPool, integer unitId, real weight returns nothing // adds specified unit-type to unitpool with given weight
native UnitPoolRemoveUnitType takes unitpool whichPool, integer unitId returns nothing // removes specified unit-type from unitpool
native PlaceRandomUnit takes unitpool whichPool, player forWhichPlayer, real x, real y, real facing returns unit // creates random unit from the unitpool, giving precedence to unit-types with higher weight
native DestroyUnitPool takes unitpool whichPool returns nothing // destroys unitpool, making it no longer usable