public GameCollection GetObjectCollection(GameObject o)
{
if (o is InfantryObject) return _infantryTypes;
else if (o is UnitObject) return _vehicleTypes;
else if (o is AircraftObject) return _aircraftTypes;
else if (o is StructureObject) {
if (_buildingTypes.HasObject(o))
return _buildingTypes;
else
return _overlayTypes;
}
else if (o is OverlayObject) return _overlayTypes;
else if (o is TerrainObject) return _terrainTypes;
else if (o is SmudgeObject) return _smudgeTypes;
else if (o is AnimationObject) return _animations;
else if (o is MapTile) return _tileTypes;
else return null;
}