Declaring functors for comparison ??
- by Mr.Gando
Hello, I have seen other people questions but found none that applied to what I'm trying to achieve here.
I'm trying to sort Entities via my EntityManager class using std::sort and a std::vector<Entity *>
/*Entity.h*/
class Entity
{
public:
float x,y;
};
struct compareByX{
bool operator()(const GameEntity &a, const GameEntity &b)
{
return (a.x < b.x);
}
};
/*Class EntityManager that uses Entitiy*/
typedef std::vector<Entity *> ENTITY_VECTOR; //Entity reference vector
class EntityManager: public Entity
{
private:
ENTITY_VECTOR managedEntities;
public:
void sortEntitiesX();
};
void EntityManager::sortEntitiesX()
{
/*perform sorting of the entitiesList by their X value*/
compareByX comparer;
std::sort(entityList.begin(), entityList.end(), comparer);
}
I'm getting a dozen of errors like
: error: no match for call to '(compareByX) (GameEntity* const&, GameEntity* const&)'
: note: candidates are: bool compareByX::operator()(const GameEntity&, const GameEntity&)
I'm not sure but ENTITY_VECTOR is std::vector<Entity *> , and I don't know if that could be the problem when using the compareByX functor ?
I'm pretty new to C++, so any kind of help is welcome.
