Struct ServerPopulatePrespawnedGhostsSystem

Responsible for assigning a unique ghostId to each pre-spawned ghost, and and adding the ghosts to the spawned ghosts maps. Relies on the previous initializations step to determine the subscene subset to process.

Implements
ISystem
ISystemCompilerGenerated
Inherited Members
Namespace: Unity.NetCode
Assembly: Unity.NetCode.dll
Syntax
[WorldSystemFilter(WorldSystemFilterFlags.ServerSimulation, WorldSystemFilterFlags.Default)]
[UpdateInGroup(typeof(PrespawnGhostSystemGroup))]
[UpdateAfter(typeof(PrespawnGhostInitializationSystem))]
[BurstCompile]
public struct ServerPopulatePrespawnedGhostsSystem : ISystem, ISystemCompilerGenerated
Remarks

The server is authoritative and it is responsible for assigning unique id ranges to the each scene. For each section that present prespawn ghosts, the prespawn hash, id range and baseline hash are sent to client as part of the streaming protocol. Clients will use the received subscene hash and baseline hash for validation and the ghost range to assign the ghost id to the pre-spawned ghosts like the server. This remove any necessity for loading order determinism. Finally, clients will ack the server about the loaded scenes and the server, upon ack receipt, will start streaming the pre-spawned ghosts

### The Full Prespawn Subscene Sync Protocol

The Server calculates the prespawn baselines. The Server assigns runtime ghost IDs to the prespawned ghosts. The Server stores the `SubSceneHash`, `BaselineHash`, `FirstGhostId`, and `PrespawnCount` inside the the `PrespawnSceneLoaded` collection. The Server creates a new ghost with a `PrespawnSceneLoaded` buffer that is serialized to the clients.

Methods

OnCreate(ref SystemState)

Called when this system is created.

Declaration
[BurstCompile]
public void OnCreate(ref SystemState state)
Parameters
Type Name Description
SystemState state

The Unity.Entities.SystemState backing this system instance
Remarks

Implement an OnCreate function to set up system resources when it is created.

OnCreate is invoked before the the first time Unity.Entities.ISystemStartStop.OnStartRunning(ref Unity.Entities.SystemState) and Unity.Entities.ISystem.OnUpdate(ref Unity.Entities.SystemState) are invoked.

See Also

OnCreateForCompiler(ref SystemState)

Generated by compilation pipeline and used internally.

Declaration
public void OnCreateForCompiler(ref SystemState state)
Parameters
Type Name Description
SystemState state

The Unity.Entities.SystemState backing this system instance
See Also

OnUpdate(ref SystemState)

Implement OnUpdate to perform the major work of this system.

Declaration
[BurstCompile]
public void OnUpdate(ref SystemState state)
Parameters
Type Name Description
SystemState state

The Unity.Entities.SystemState backing this system instance
Remarks

By default, the system invokes `OnUpdate` once every frame on the main thread. To skip OnUpdate if all of the system's [EntityQueries] are empty, use the [RequireMatchingQueriesForUpdateAttribute]. To limit when OnUpdate is invoked, you can specify components that must exist, or queries that match specific Entities. To do this, call Unity.Entities.SystemState.RequireForUpdate<T>() or Unity.Entities.SystemState.RequireForUpdate(Unity.Entities.EntityQuery) in the system's OnCreate method. For more information, see Unity.Entities.SystemState.ShouldRunSystem().

You can instantiate and schedule an Unity.Entities.IJobChunk instance; you can use the [C# Job System] or you can perform work on the main thread. If you call Unity.Entities.EntityManager methods that perform structural changes on the main thread, be sure to arrange the system order to minimize the performance impact of the resulting [sync points]. 

 [sync points]: xref:concepts-structural-changes
 [C# Job System]: https://docs.unity.cn/Manual/JobSystem.html
 [EntityQueries]: xref:Unity.Entities.EntityQuery
 [RequireMatchingQueriesForUpdateAttribute]: xref:Unity.Entities.RequireMatchingQueriesForUpdateAttribute
See Also

Implements

Unity.Entities.ISystem
Unity.Entities.ISystemCompilerGenerated

See Also