Create an entity with a specific id about esper HOT 4 CLOSED

Thanks for opening the ticket, and I'm glad you're enjoying esper.

Can I ask why it's important that entities have the same ID after loading?
The proposed patch would work, but it's a bit outside of typical ECS structure.
The Entity ID happens to be an integer, but it's meant as a throw-away value.

Instead of storing the ID, if possible, I would recommend using a Component to "tag" specific Entities.

class Player:
    pass

class EnemyTypeA:
    pass

class EnemyTypeB:
    pass

There may of course be multiple of the enemy types, but there would only be one entity tagged with Player. This allows you to specifically query that entity, if you need to.

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I already use components as "Tags" and it works fine how i use it but my game has "unpredictable" Enemies aka an Entity with a random set of Components. It may work with a restructure of my db layout. I might make it possible without using the entity id as a key but changing components would be hard.

having a db without entity id as key might be look like this:
Entity

that way i have just one table in my db (what i don't really want to happen) and i don't need the entity id as a key as i can distinguish by the components. Now just imaging what i have to do to change the Position of a specific entity. i gets messy real fast.

my other solution would be to add a secondary id component to my entities like a RandomEntity having components Position, Color, Faction, etc AND a must have SecondaryIdComponent() like a string or another int which is different for every Entity.

It just might be "the problem saving ECS to a DB". I've never done it and it might be a stupid use case but i want to do like that to learn it.

Having a way to create known entities with specific ids would be the easiest solution for me. if it's not complieant with an ECS than that's ok. I have ways to work around it but it would make my life a little bit easier :D

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Sorry for leaving this hanging for so long.
I think for the main Esper releases I want to keep it as-is, just for performance reasons (even if very small).

That said, it would be pretty easy to subclass World with a custom create_known_entity(id) method. It could probably work alongside the existing method as well. Would that work for you?

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Closing this due to lack of follow up.
On careful consideration, I don't think this makes sense in mainline esper, due to placing relevance on what is supposed to be nothing more than a UUID (even if it's an int in implementation).

This behavior can be achieved using a custom function. If you need help in producing something like that, please follow up or open a new ticket. Thanks!

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