/// <summary>
/// Creates a delta between a state and a record. If forceUpdate is set
/// to false, this function will return null if there is no change between
/// the current and basis.
/// </summary>
internal static RailStateDelta CreateDelta(
EntityId entityId,
RailState current,
RailStateRecord basisRecord,
bool includeControllerData,
bool includeImmutableData,
Tick commandAck,
Tick removedTick)
{
bool shouldReturn =
includeControllerData ||
includeImmutableData ||
removedTick.IsValid;
uint flags = RailState.FLAGS_ALL;
if ((basisRecord != null) && (basisRecord.State != null))
{
flags = current.CompareMutableData(basisRecord.State);
}
if ((flags == 0) && (shouldReturn == false))
{
return(null);
}
RailState deltaState = RailState.Create(current.factoryType);
deltaState.Flags = flags;
deltaState.ApplyMutableFrom(current, deltaState.Flags);
deltaState.HasControllerData = includeControllerData;
if (includeControllerData)
{
deltaState.ApplyControllerFrom(current);
}
deltaState.HasImmutableData = includeImmutableData;
if (includeImmutableData)
{
deltaState.ApplyImmutableFrom(current);
}
deltaState.RemovedTick = removedTick;
deltaState.CommandAck = commandAck;
// We don't need to include a tick when sending -- it's in the packet
RailStateDelta delta = RailResource.Instance.CreateDelta();
delta.Initialize(Tick.INVALID, entityId, deltaState, false);
return(delta);
}
/// <summary>
/// Creates a record of the current state, taking the latest record (if
/// any) into account. If a latest state is given, this function will
/// return null if there is no change between the current and latest.
/// </summary>
internal static RailStateRecord CreateRecord(
Tick tick,
RailState current,
RailStateRecord latestRecord = null)
{
if (latestRecord != null)
{
RailState latest = latestRecord.State;
bool shouldReturn =
(current.CompareMutableData(latest) > 0) ||
(current.IsControllerDataEqual(latest) == false);
if (shouldReturn == false)
{
return(null);
}
}
RailStateRecord record = RailResource.Instance.CreateRecord();
record.Overwrite(tick, current);
return(record);
}
