Games.ECS.World

Infrastructure for defining ECS worlds.

Documentation

data Access

HKD parameterisation for an ECS.

Constructors

Storing

We are dealing with the entire collection of entities in a world, represented structure-of-array style.

Individual

We are dealing with a specific individual with specific component values.

data Props

Different arities.

Constructors

Normal

An individual may or may not have this component.

Required

Every individual must have this component.

Unique

Either a single individual, or none, may have this component.

class World (w :: Access -> Type) where

An entity component system, parameterised by its access type.

Minimal complete definition

newWorld, createNewEntityWithRef, entityReference, unsafeEntityReference, entityReferences, lookupEntity, prototype, storeEntity

Methods

newWorld :: w 'Storing

Construct a new world.

createNewEntity :: MonadIO m => m (w 'Individual)

Create a new entity

createNewEntityWithRef :: Entity -> w 'Individual

Create a new entity with a given reference.

entities :: IndexedTraversal' Entity (w 'Storing) (w 'Individual)

Traversal over all entities in the ECS.

default entities :: HasType EntRefStoringType (w 'Storing) => IndexedTraversal' Entity (w 'Storing) (w 'Individual)

entityReference :: IndexedGetter Entity (w 'Individual) Entity

Get the entity reference of an individual

unsafeEntityReference :: Lens' (w 'Individual) Entity

Get and set the entity reference of an individual

entityReferences :: IndexedFold Entity (w 'Storing) Entity

Get all of the entity references stored in the world.

lookupEntity :: w 'Storing -> Entity -> Maybe (w 'Individual)

Check if a given entity exists in the world, and if so, return the individual.

prototype :: HasPrototypeID p => p -> AffineTraversal' (w 'Storing) (w 'Individual)

Get a prototype specification from its name.

lookupEntities :: forall f p fol. (Indexable Entity p, Applicative f, Foldable fol) => fol Entity -> p (w 'Individual) (f (w 'Individual)) -> w 'Storing -> f (w 'Storing)

An IndexedTraversal' which returns the individuals associated to the entities given as input.

entitiesWith :: forall f p. (Indexable Entity p, Applicative f) => (forall r. Monoid r => Getting r (w 'Storing) IntersectionOfEntities) -> p (w 'Individual) (f (w 'Individual)) -> w 'Storing -> f (w 'Storing)

An IndexedTraversal' of individuals matching some constraints. The constraints are included monoidally.

storeEntity :: w 'Individual -> w 'Storing -> w 'Storing

Store an individual in a world, returning the new world.

entity :: Entity -> AffineTraversal' (w 'Storing) (w 'Individual)

Affine traversal for a specified individual from the world.

type family OpticsFor (name :: Symbol) (hkd :: Access -> Type) (acc :: Access) (p :: Props) a where ...

We want to make sure that the API is consistent based on the access type and availability property, so we have a type family to give us the correct optics.

Equations

OpticsFor name hkd 'Individual 'Required a = ReifiedIndexedLens' Entity (hkd 'Individual) a

OpticsFor name hkd 'Individual 'Normal a = AnAffineTraversal' (hkd 'Individual) a

OpticsFor name hkd 'Individual 'Unique a = AnAffineTraversal' (hkd 'Individual) a

OpticsFor name hkd 'Storing 'Unique a = ReifiedIndexedTraversal' Entity (hkd 'Storing) a

OpticsFor name hkd 'Storing 'Normal a = ReifiedIndexedTraversal' Entity (hkd 'Storing) a

OpticsFor name hkd 'Storing 'Required a = ReifiedIndexedTraversal' Entity (hkd 'Storing) a

type EntRefStoringType = IntSet

A type which holds a collection of Entity.

type family EntRefField (acc :: Access) where ...

A type function for simplifying the higher-kinded data implementation.

Equations

EntRefField 'Individual = Entity

EntRefField 'Storing = EntRefStoringType

type AnAffineTraversal s t a b = ReifiedIndexedTraversal Entity s t a b

A reified AffineTraversal.

type AnAffineTraversal' s a = AnAffineTraversal s s a a

A reified AffineTraversal'.

type AffineTraversal s t a b = Traversal s t a b

An AffineTraversal is one which traverses either 0 or 1 elements.

type AffineTraversal' s a = AffineTraversal s s a a

Simplified AffineTraversal.

affine :: (s -> Either t a) -> (s -> b -> t) -> Traversal s t a b

Construct an AffineTraversal.

affine' :: (s -> Maybe a) -> (s -> a -> s) -> Traversal' s a

Construct an AffineTraversal'.

newUniqueEntRef :: IO Entity

Atomically construct a new entity reference.