Ensure replication of variable on a client

Development Programming & Scripting C++
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1

I have a method that, on button input, checks value on PlayerState and, if check successful, sends RPC back:

void UAbilityController::OnSpellUpgradeButtonClicked(USpellWidget* SpellWidget)
{
	ATBCPlayerState* TBCPlayerState{StaticCast<ATBCPlayerState*>(PlayerState)};
	if (TBCPlayerState->GetSpellPoints() <= 0u) return;
        ....
        TBCPlayerState->Server_AddSpellPoints(-1);

The problem is that when on a client, replication is not immediate, and replicated value is often faulty, i.e. i can spam button fast and bypass check. How can i fix this situation? I tried adding lock guards to both AbilityController and PlayerState, didn’t help. I can’t make OnSpellUpgradeButtonClicked a Server RPC, because it resides on HUD.

The way I handle it right now is just invoke AddSpellPoints on client:

if (PlayerController->IsNetMode(NM_Client))
	{
		GEngine->AddOnScreenDebugMessage(
			-1, 3.f, FColor::Orange, TEXT("Client net mode"));
		// Replication takes time, so change client value too, to ensure upgrade cannot be spammed
		TBCPlayerState->AddSpellPoints(-1);
	}

This way, on next button spam, value will be updated, and replication will validate that.

2

Okay, finally found solution to use ForceNetUpdate() method. It forces the replication immediately.