@Edit: I can't edit the title, I mean Hierarchy Entity System, sorry.

I've been working on a simple game with C++/SDL using hierarchy entities and I've been running into some problems to make the entities deal with the map in a intelligible way. I'm using the common way of states, currently having a Start Menu state and a Main Game state.

Map::Update()
{
	Player->Update();
	(for each Enemy) Enemy->Update();
		
	int MoveParam = IsMoveValid(Player->MovingDirection, Player->X, PlayerY);
	Player->Move(MoveParam);
	(for each Enemy) MoveParam = IsMoveValid(Enemy->MovingDirection, Enemy->X, Enemy->Y);
	Enemy->Move(MoveParam);
}

I think the entities having a reference to the map, and vice versa is the way to go. when the entity needs to get a path, it can query the map, which can use a* or other pathfinding to return the path to the entity. If your entity needs to query for nearest enemy or what not, it can query the map, which knows all entities already. In an ECS system, I would have a pathfinding system to handle the logic, which would have a reference to the map, and use the entities position component to get starting information for the graph search.

You could pass the Map object by reference:

 player->update(theMap);
 (for each Enemy) enemy->update(theMap);

There's really nothing wrong with passing objects through function calls to the objects that depend on them.

You could pass the Map object by reference:

 player->update(theMap);
 (for each Enemy) enemy->update(theMap);

There's really nothing wrong with passing objects through function calls to the objects that depend on them.

I thought about doing something like that, but I don't know, it just don't feels right to be passing everything through parameters. Perhaps I'm just too paranoid. I also had some problems with circular dependency when I first tried doing that, but this is probably some mess I did with the code.

I think the entities having a reference to the map, and vice versa is the way to go. when the entity needs to get a path, it can query the map, which can use a* or other pathfinding to return the path to the entity. If your entity needs to query for nearest enemy or what not, it can query the map, which knows all entities already. In an ECS system, I would have a pathfinding system to handle the logic, which would have a reference to the map, and use the entities position component to get starting information for the graph search.

I was thinking of something like that, like the entities storing a pointer for the current map and vice versa, though I feel like I'm going to have some headache to implement that at first. I'll give some more thought and research on the matter before what I'm really going to do.

Thank you guys!

You could pass the Map object by reference:

 player->update(theMap);
 (for each Enemy) enemy->update(theMap);

There's really nothing wrong with passing objects through function calls to the objects that depend on them.

I thought about doing something like that, but I don't know, it just don't feels right to be passing everything through parameters. Perhaps I'm just too paranoid. I also had some problems with circular dependency when I first tried doing that, but this is probably some mess I did with the code.

I think the entities having a reference to the map, and vice versa is the way to go. when the entity needs to get a path, it can query the map, which can use a* or other pathfinding to return the path to the entity. If your entity needs to query for nearest enemy or what not, it can query the map, which knows all entities already. In an ECS system, I would have a pathfinding system to handle the logic, which would have a reference to the map, and use the entities position component to get starting information for the graph search.

I was thinking of something like that, like the entities storing a pointer for the current map and vice versa, though I feel like I'm going to have some headache to implement that at first. I'll give some more thought and research on the matter before what I'm really going to do.

Thank you guys!

You may find this a good read

You could pass the Map object by reference:

 player->update(theMap);
 (for each Enemy) enemy->update(theMap);

There's really nothing wrong with passing objects through function calls to the objects that depend on them.

I thought about doing something like that, but I don't know, it just don't feels right to be passing everything through parameters. Perhaps I'm just too paranoid. I also had some problems with circular dependency when I first tried doing that, but this is probably some mess I did with the code.

Well, you're not passing everything, are you? Just the map. If updating your entity requires the map, pass it in. If at some point you find you're passing 10 arguments into your method, perhaps that method is doing too much work, and should be split up into more functions that do specific work and each takes 1-2 arguments. Also, this actually solves circular dependencies, as in this case, the Entity doesn't need to be created with a Map reference.

I think the entities having a reference to the map, and vice versa is the way to go. when the entity needs to get a path, it can query the map, which can use a* or other pathfinding to return the path to the entity. If your entity needs to query for nearest enemy or what not, it can query the map, which knows all entities already. In an ECS system, I would have a pathfinding system to handle the logic, which would have a reference to the map, and use the entities position component to get starting information for the graph search.

I was thinking of something like that, like the entities storing a pointer for the current map and vice versa, though I feel like I'm going to have some headache to implement that at first. I'll give some more thought and research on the matter before what I'm really going to do.

Thank you guys!

If you don't store the Map into entities, but pass it into an update() method or move() method, then you have no headaches on rewriting anything, and the entity updates based on the map you give it. If the entity changes the map it's in, it doesn't need to know that at all, you just pass in a different map.

My advice would be to do what's easiest (which is argument passing), and refactor later if it proves (through usage) to be ineffective or hard to use.

The first solution I thought I was declaring the map Static, this way everyone could access it in their classes. But I personally dislike using static objects, and I heard it's not a good idea to do it on games,

why not using statics in games? can you elaborate?