advanced library

Internal ECS APIs.

Classes

AccessConflict
A detected access conflict between two systems in the same schedule that have no ordering relationship and touch the same component in a conflicting way.
App
Runs a World through named schedules.
AppBuilder
Registers app systems and data.
AppDiagnostics
Opt-in diagnostics configuration for an App.
AxisInput<T>
Analog input values, keyed by axis type T.
ButtonInput<T>
Held button state, keyed by action type T.
Commands
Queues structural world changes.
ComponentStore
CurrentState<S extends Object>
The active value of the state machine for S.
DespawnAfter
Despawns an entity after remaining seconds.
DespawnAfterSystem
Advances all DespawnAfter timers.
DespawnOnExit
Despawns an entity when its state ends.
Disposable
A resource that needs cleanup.
EcsFrameLoop
Runs frame schedules and updates time.
Entity
A lightweight, generational handle to an entity.
EntityCommands
Fluent deferred commands targeting one entity.
EntityDetailSnapshot
Component details for one entity.
EntityQuery
EntityRegistry
Allocates and validates Entity handles.
EntitySnapshot
A live entity summary.
EventChannel<T>
A buffered event channel with independent readers.
EventChannelSnapshot
One event channel: its event type name, buffered-event count, and whether the most recent maintenance pass found a lagging reader.
EventCursorHost
Stores event readers for one system.
EventReader<T>
A cursor-based reader over an EventChannel.
EventWriter<T>
A handle that appends events to an EventChannel.
FixedTime
Fixed-step timing, updated each fixed update before the physics step.
FrameTime
Per-frame timing, updated at the start of each rendered frame.
GameBuilder
Registers game features.
GameClock
The global gameplay clock for pause, slow motion, and hitstop.
GameStopwatch
Counts up without a target.
GameTimer
Counts up to a duration, reporting completion once or repeatedly.
InputBuffer<T>
Keeps recent input actions in order.
InspectorSnapshot
A summary of one world.
Machine<S>
Stores the current state, time in state, and transition edges.
Name
A readable entity label.
NextState<S extends Object>
Where systems queue a transition for the state machine of S.
ObjectComponentStore<T>
ObserverDispatch
The value World.runningSystem holds while observer callbacks run.
ObserverRegistry
Stores observers for one world.
OnEnter
The one-shot schedule run when the state machine transitions to value (including the initial value during App.start).
OnExit
The one-shot schedule run when the state machine transitions away from value.
OptionalSingle<A>
OwnedBy
Despawns this entity when owner dies.
Plugin
Registers one app feature.
Query1<A>
Query2<A, B>
Query3<A, B, C>
Query4<A, B, C, D>
QueryView1<A extends Object>
A query over one component type.
QueryView2<A extends Object, B extends Object>
A query over two component types.
QueryView3<A extends Object, B extends Object, C extends Object>
A query over three component types.
QueryView4<A extends Object, B extends Object, C extends Object, D extends Object>
A query over four component types.
RemoveAfterTracker
Tracks component removal deadlines.
Repeat<L extends Step<L>>
Re-enters child times times, or forever when times is null.
Resources
Stores one resource per type.
ResourceSnapshot
One resource: its type name and, when the instance overrides Object.toString (same default-Instance of filter as debugDescribe), that rendering.
Routine<L extends Step<L>>
Where one entity is in its plan.
SceneDashBundle
Inserts a group of components.
ScheduleLabel
A stable identifier for a schedule (a named phase of the frame).
Schedules
Built in frame schedules.
Select<L extends Step<L>>
Runs children until one succeeds. Fails when every child fails.
Sequence<L extends Step<L>>
Runs children in order. Fails on the first child that fails.
Single<A>
SlowSystemEvent
Emitted when a system's run exceeds the configured slow-system threshold.
SnapshotCollector
Collects InspectorSnapshot data on demand.
SpawnQueue
Stores pending spawns for one world.
StateScheduleLabel
A schedule that belongs to a state value's enter/exit lifecycle.
Step<L extends Step<L>>
A node in a plan.
StoreRegistry
Maps component types to stores.
StoreSnapshot
A component or tag store: its type name and dense row count.
SystemAccess
Component types read and written by a system.
SystemAccessProvider
Provides access data for a system.
SystemAdapter
Runs one system.
SystemDescriptor
Describes a schedulable system.
SystemLabel
A stable identifier for a single registered system.
SystemProfiler
Collects system timings by schedule.
SystemRef
Stable identity for a system.
SystemSet
A named system phase.
SystemSnapshot
Timing for one system and schedule.
SystemTiming
A reusable, read-only timing record for a single (system, schedule) pair, accumulated across frames.
Tag
A marker for presence-only components.
TagStore
TestGame
Runs game logic without Flutter.
World
Stores entities, components, resources, and events.

Enums

AccessConflictPolicy
How the app reacts to detected AccessConflicts during start().
ButtonEdge
The transition a button crossed when its pressed state was updated.
ConflictKind
The kind of access hazard between two unordered systems.
StepResult
What a driver reports about the leaf it just ran.

Extensions

AppBuilderSystems on AppBuilder
Adds systems as a group.
ClassicWorldQueries on World
Query constructors that return query classes.
RunConditionOps on RunCondition
Short-circuiting composition of RunConditions.
WorldDebugDescribe on World
One-line entity descriptions for logs and assertion messages.
WorldSurface on World

Functions

advanceInputBuffers(Iterable<Object> resources, double unscaledDt) → void
Advances every automatic input buffer.
every(double seconds) → RunCondition
Passes once every seconds of game time.
hasEvents<T>() → RunCondition
Passes while the event channel for T has buffered events.
hasResource<T extends Object>() → RunCondition
Passes while a resource of type T is registered.
inState<S extends Object>(S value) → RunCondition
A run condition that passes while the state machine for S is at value.
not(RunCondition condition) → RunCondition
A condition that passes when condition does not.

Typedefs

ComponentObserver<T> = void Function(World world, Entity entity, T component)
Runs after a component is added or removed.
EntityQueryCallback = void Function(Entity entity)
EntityQueryUntilCallback = bool Function(Entity entity)
Feature = void Function(GameBuilder game)
Registers one game feature.
Query1Callback<A> = void Function(Entity entity, A a)
Query1UntilCallback<A> = bool Function(Entity entity, A a)
Query2Callback<A, B> = void Function(Entity entity, A a, B b)
Query2UntilCallback<A, B> = bool Function(Entity entity, A a, B b)
Query3Callback<A, B, C> = void Function(Entity entity, A a, B b, C c)
Query3UntilCallback<A, B, C> = bool Function(Entity entity, A a, B b, C c)
Query4Callback<A, B, C, D> = void Function(Entity entity, A a, B b, C c, D d)
Query4UntilCallback<A, B, C, D> = bool Function(Entity entity, A a, B b, C c, D d)
RunCondition = bool Function(World world)
Decides whether a system runs.
WorldSystem = void Function(World world)
A system that updates the world.