SpawnActor use a ROLE_SimulatedProxy actor as template will be crash

Development Programming & Scripting Multiplayer & Networking
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1

FActorSpawnParameters SpawnInfo;
SpawnInfo.Template = RemoteActor; //ROLE_SimulatedProxy
SpawnInfo.SpawnCollisionHandlingOverride = ESpawnActorCollisionHandlingMethod::AlwaysSpawn;
SpawnInfo.bNoFail = true;
SpawnInfo.ObjectFlags = RF_Transient;
NewActor = GetWorld()->SpawnActor(RemoteActor->GetClass(), SpawnInfo);

there will be crash at AActor::PostSpawnInitialize, line 2746:
check(Role == ROLE_Authority);

2

Hey windywang,

How are you initializing your RemoteActor template? Could you provide that code as well?

3

in a multiplayer game, “remote player” is another player in local client

4

Could you please provide some additional information regarding your crash:

  • Are you getting a crash reporter window? If so, please provide your LoginID and ensure to hit Send & Close on the report.
  • Could you please provide logs from your project’s Saved->Logs folder from after the crash occurs?
  • Could you please provide your full code for this issue so we can ensure we are following your repro?

Thanks

5

Assertion failed: Role == ROLE_Authority [File:UnrealEngine4.15\Engine\Source\Runtime\Engine\Private\Actor.cpp] [Line: 2746]

that’s because the “Template” of FActorSpawnParameters is ROLE_SimulatedProxy, and the “Role” property value is copied to the new spawned actor.
you can ask your engineer, it is very easy to understand

6

Hey windywang,

After further investigation, it appears this crash is occurring because you are attempting to spawn an actor on the server that is something other than ROLE_Authority. All actors on the server must be authoritative, otherwise this check will fail. As a result, I do not believe that this is a bug. I was able to replicate the crash, but it seems like intended behavior based on the current documentation and my understanding of Actor Roles: Actor Role and RemoteRole | Unreal Engine Documentation

Let me know if you have further questions or comments regarding this.

Have a great day