[Fluid] Convenient entity matching

Quick notes. Sorry for mess!

(From a jam perspective) aspects are currently a quite laborious aspect of ODB. it’s a pain writing out the predicates for a system or queries to the subscription manager. There’s some areas we could improve things:

Query singletons

Believe there are opportunities to solve the following query in a more succinct manner.

E(world.getAspectSubscriptionManager().get(Aspect.all(BathroomLevel.class)).getEntities().get(0))

Don’t know about others but having to inspect or alter a singleton that falls outside the scope of my system aspects is a fairly common thing. Delegating to a specialized passive system might be the proper way to do it, but the verbosity of resolving the singleton remains.

Something like E(BathroomLevel.class) could do the trick.

Query + iterating lists

Same with this query:

        IntBag actives = world.getAspectSubscriptionManager().get(Aspect.all(Hammer.class)).getEntities();
        int[] ids = actives.getData();
        for (int i = 0, s = actives.size(); s > i; i++) {

We could follow a jQuery style batch-operations All(Hammer.class).visible(true).do(myOperation) or perhaps the more practical for(E e : All(Hammer)), can’t really weigh the performance costs of having an iterator. I guess a per-composition iterator wouldn’t be too costly or limiting?

Constructors Will not do. IntellIJ quick-creating a constructor forcefully maps the Aspect.Builder as a parameter.

public class MyExampleSystem extends BaseEntitySystem {
    public MyExampleSystem(Aspect.Builder aspect) {
        super(aspect);
    }
}

Bit of a hack but I’ve been using a no-arg constructor (with Aspect.all()) in the hierarchy to save time in this regard.

[DaanVanYperen]

To keep things extensible and easy to grok settled on:

Group

        for (E gun : E.withGroup("player-guns")) {
            gun.firing(true);
        }

If anyone has a better naming suggestion i’m all for it. was considering E.group(..), E.allWithGroup(..), perhaps E.entitiesWithGroup(..) since E tends to get statically imported.

Tag

       E player = E.withTag("player");

Subscription

 for ( E e : E.withAspect(Aspect.all(Pickup.class, Pos.class)) ) { .. }
 for ( E e : E.withComponent(Pickup.class) ) { .. }

edit 1&2: Added tag, subscription

[DaanVanYperen]

High value ticket for me, I’d love a convenient and fast API to retrieve by tag/group/composition and operate on sets.