private bool DoAction(TrackWriter track, GameLine beforeact, GameLine afteract)
{
if (beforeact == null && afteract == null)
{
throw new ArgumentNullException(
"undo action with no values");
}
// remove line
if (afteract == null)
{
track.RemoveLine(beforeact);
}
// add line
else if (beforeact == null)
{
track.AddLine(afteract.Clone());
}
// Replace line
else if (beforeact.Type != afteract.Type)
{
track.RemoveLine(beforeact);
track.AddLine(afteract);
}
//move action
else
{
track.ReplaceLine(beforeact, afteract.Clone());
}
return(!(beforeact is SceneryLine));
}
public void Redo(TrackWriter track)
{
bool physchanged = false;
for (int i = 0; i < States.Count - 1; i += 2)
{
physchanged |= DoAction(track, States[i], States[i + 1]);
}
if (physchanged)
{
track.NotifyTrackChanged();
}
}
public TrackWriter CreateTrackWriter()
{
return(TrackWriter.AcquireWrite(_tracksync, _track, _renderer, UndoManager, Timeline, _cells));
}