Resources and local state
Share singleton data between systems and keep per-system state.
[Resource, TrackChanges]
public readonly record struct FrameTime(float DeltaSeconds);
[Resource(OwnerThread = true)]
public readonly record struct WindowHandle(nint Value);System parameters
| Parameter | Capability |
|---|---|
scoped Res<T> |
Readonly access to a required unmanaged resource. |
scoped ResMut<T> |
Writable access to a required unmanaged resource. |
scoped OptionalRes<T> |
Readonly access to a registered resource that may be absent. HasValue guards Value. |
scoped ManagedRes<T> |
Access to a managed resource class, exclusively on the owner thread. |
scoped Local<T> |
Mutable Value belonging to this system instance, initially default(T). |
Presence and registration
Required resources must be present at binding and before each execution. An optional resource still requires type registration. Res<T> and OptionalRes<T> expose IsAdded and IsChanged when tracking is enabled.
Owner-thread affinity
[Resource(OwnerThread = true)] keeps an unmanaged resource’s system on the owner thread. Disjoint worker work may overlap that system. Managed resources and reference-containing locals make their system exclusive.
Ownership
| Call | Ownership |
|---|---|
world.InsertResource(value) |
The world borrows the value. |
world.InsertOwnedResource(value) |
Transfers ownership of a managed IDisposable value to the world. |
world.RemoveResource<T>() |
Removes and disposes an owned value once. |
world.TakeResource<T>() |
Removes a value and transfers its ownership to the caller. |
world.GetResource<T>() |
Returns the resource value. |
Replacing an owned resource disposes the previous one once.
Local state
Each repeated registration and each bound schedule has independent locals, query change cursors, and message-reader cursors.