UCharacterMovementComponent::ClientUpdatePositionAfterServerUpdate

Development Programming & Scripting C++
1

Hi all. I have some questions about UCharacterMovementComponent
Why are we need to use the function : UCharacterMovementComponent::ClientUpdatePositionAfterServerUpdate for call SavedMoves again?

Do we not have used them earlier in ReplicateMoveToServer ? + we get some corrections later in ClientAdjustPosition_Implementation:



        // Trust the server's positioning.
	UpdatedComponent->SetWorldLocation(WorldShiftedNewLocation, false);
	Velocity = NewVelocity;

	// Trust the server's movement mode
	UPrimitiveComponent* PreviousBase = CharacterOwner->GetMovementBase();
	ApplyNetworkMovementMode(ServerMovementMode);

Why are we use ClientUpdatePositionAfterServerUpdate after this ?

2

The place(ClientAdjustPosition_Implementation) where ClientData->bUpdatePosition is set to = true also call ClientData->AckMove(MoveIndex) = deleted all Moves and then in ClientUpdatePositionAfterServerUpdate :



// Replay moves that have not yet been acked.
	for (int32 i=0; i<ClientData->SavedMoves.Num(); i++)
	{
		const FSavedMovePtr& CurrentMove = ClientData->SavedMoves*;
		CurrentMove->PrepMoveFor(CharacterOwner);  
		MoveAutonomous(CurrentMove->TimeStamp, CurrentMove->DeltaTime, CurrentMove->GetCompressedFlags(), CurrentMove->Acceleration);
		CurrentMove->PostUpdate(CharacterOwner, FSavedMove_Character::PostUpdate_Replay);
	}

But before this function we deleted all of these SavedMoves! Saved only 1 in LastAckedMove, but this LastAckedMove is not part of the ClientData->SavedMoves

Is it deleting all, right?


// And finally cull all of those, so only the unacknowledged moves remain in SavedMoves.
		const bool bAllowShrinking = false;
		SavedMoves.RemoveAt(0, AckedMoveIndex + 1, bAllowShrinking);

AckedMoveIndex - last element, then AckedMoveIndex + 1 = all

In what cases it can call these movements?
Or maybe I confuse something…