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    Struct BufferLookup<T>

    A [NativeContainer] that provides access to all instances of DynamicBuffer components with elements of type T, indexed by Entity.

    Namespace: Unity.Entities
    Assembly: Unity.Entities.dll
    Syntax
    [NativeContainer]
    public struct BufferLookup<T> where T : unmanaged, IBufferElementData
    Type Parameters
    Name Description
    T

    The type of IBufferElementData to access.

    Remarks

    BufferLookup is a native container that provides array-like access to DynamicBuffer components of a specific type. For example, while iterating over a set of entities, you can use BufferLookup to get and set DynamicBuffers of unrelated entities.

    To get a BufferLookup, call GetBufferLookup<T>(bool).

    Pass a BufferLookup container to a job by defining a public field of the appropriate type in your IJob implementation. You can safely read from BufferLookup in any job, but by default, you cannot write to components in the container in parallel jobs (including IJobEntity, Query<T1>() and IJobChunk). If you know that two instances of a parallel job can never write to the same index in the container, you can disable the restriction on parallel writing by adding NativeDisableParallelForRestrictionAttribute to the BufferLookup field definition in the job struct.

    Properties

    Name Description
    this[Entity]

    Gets the DynamicBuffer<T> instance of type T for the specified entity.

    Methods

    Name Description
    DidChange(Entity, uint)

    Reports whether any of IBufferElementData components of the type T, in the chunk containing the specified Entity, could have changed.

    EntityExists(Entity)

    Reports whether the specified entity exists. Does not consider whether this buffer exists on the given entity.

    GetComponentEnabledRefROOptional<T2>(Entity)

    Obsolete. Use GetEnabledRefROOptional<T2>(Entity) instead.

    GetComponentEnabledRefRWOptional<T2>(Entity)

    Obsolete. Use GetEnabledRefRWOptional<T2>(Entity) instead.

    GetEnabledRefROOptional<T2>(Entity)

    Gets a safe reference to the component enabled state.

    GetEnabledRefRO<T2>(Entity)

    Gets a safe reference to the component enabled state.

    GetEnabledRefRWOptional<T2>(Entity)

    Gets a safe reference to the component enabled state.

    GetEnabledRefRW<T2>(Entity)

    Gets a safe reference to the buffer component enabled state.

    HasBuffer(Entity)

    Reports whether the specified Entity instance still refers to a valid entity and that it has a buffer component of type T.

    HasBuffer(Entity, out bool)

    Reports whether the specified Entity instance still refers to a valid entity and that it has a buffer component of type T.

    HasComponent(Entity)

    Obsolete. Use HasBuffer(Entity) instead.

    IsBufferEnabled(Entity)

    Checks whether the IBufferElementData of type T is enabled on the specified Entity. For the purposes of EntityQuery matching, an entity with a disabled component will behave as if it does not have that component. The type T must implement the IEnableableComponent interface.

    IsComponentEnabled(Entity)

    Obsolete. Use IsBufferEnabled(Entity) instead.

    SetBufferEnabled(Entity, bool)

    Enable or disable the IBufferElementData of type T on the specified Entity. This operation does not cause a structural change (even if it occurs on a worker thread), or affect the value of the component. For the purposes of EntityQuery matching, an entity with a disabled component will behave as if it does not have that component. The type T must implement the IEnableableComponent interface.

    SetComponentEnabled(Entity, bool)

    Obsolete. Use SetBufferEnabled(Entity, bool) instead.

    TryGetBuffer(Entity, out DynamicBuffer<T>)

    Retrieves the buffer components associated with the specified Entity, if it exists. Then reports if the instance still refers to a valid entity and that it has a buffer component of type T.

    TryGetBuffer(Entity, out DynamicBuffer<T>, out bool)

    Retrieves the buffer components associated with the specified Entity, if it exists. Then reports if the instance still refers to a valid entity and that it has a buffer component of type T.

    Update(SystemBase)

    When a BufferLookup is cached by a system across multiple system updates, calling this function inside the system's OnUpdate() method performs the minimal incremental updates necessary to make the type handle safe to use.

    Update(ref SystemState)

    When a BufferLookup is cached by a system across multiple system updates, calling this function inside the system's OnUpdate() method performs the minimal incremental updates necessary to make the type handle safe to use.


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