private TileChange ApplyChange(TileChange change)
{
TileChange undoChange = new TileChange(change.X, change.Y, change.Width, change.Height, this.trackMap);
this.trackMap.SetTiles(change.X, change.Y, change);
return(undoChange);
}
private void Add(IEnumerable <TileChange> changes)
{
if (this.undoBuffer.Count == Limit)
{
this.undoBuffer.RemoveFirst();
}
this.redoBuffer.Clear();
// Consolidate tile changes into a single one
TileChange change = new TileChange(changes, this.trackMap);
this.undoBuffer.AddLast(change);
}
/// <summary>
/// Reapplies the last undone change.
/// </summary>
/// <returns>The change that has been reapplied.</returns>
public TileChange Redo()
{
if (!this.HasRedo || this.buffer != null)
{
// Nothing to redo, or a change is already ongoing
return(null);
}
TileChange redoChange = this.redoBuffer.First.Value;
TileChange undoChange = this.ApplyChange(redoChange);
this.redoBuffer.RemoveFirst();
this.undoBuffer.AddLast(undoChange);
return(redoChange);
}
public void Add(TileChange change)
{
if (this.buffer == null)
{
this.BeginAdd();
this.Add(change);
this.EndAdd();
}
else
{
this.buffer.Push(change);
if (this.buffer.Count == ChangeLimit)
{
// Consolidate tile changes to improve performances
TileChange tileChange = new TileChange(this.buffer, this.trackMap);
this.buffer.Clear();
this.buffer.Push(tileChange);
}
}
}