fix(editor): load spawn/house files on session restore

When restoring a session, the editor was only loading the OTBM map
but not the external spawn/house XML files. This caused spawns to be
empty in memory, and saving would overwrite the spawn file with an
empty <spawns/> element, losing all configured spawns.

Now LoadSessionFiles also reads the external spawn and house XML
files after loading the OTBM, matching the behavior of LoadMapFromPath.

Author: BrewertonSantos

src/App/AppSettings.cs

@@ -37,6 +37,7 @@ public class AppSettings
     /// <summary>Recent session snapshots (newest first). Capped at 20.</summary>
     public List<SessionHistoryEntry> History { get; set; } = [];
     public int ItemsPerPage { get; set; } = 100;
+    public int PreferredDirection { get; set; }
 
     private static string SettingsFilePath =>
         Path.Combine(

src/App/Controls/MapCanvasControl.cs

@@ -1023,7 +1023,7 @@ public override void Render(DrawingContext context)
                     context.DrawLine(erasePen, new Point(gx + tilePixelSize - 4, gy + 4), new Point(gx + 4, gy + tilePixelSize - 4));
                 }
             }
-            else if (ActiveZoneBrush > 0)
+            else if (ActiveZoneBrush != 0)
             {
                 // Show zone color preview
                 Color zoneColor = ActiveZoneBrush switch
@@ -1032,6 +1032,7 @@ public override void Render(DrawingContext context)
                     4 => Color.FromArgb(80, 0, 200, 255),   // NoPvP
                     2 => Color.FromArgb(80, 255, 255, 0),   // NoLogout
                     8 => Color.FromArgb(80, 255, 0, 0),     // PvPZone
+                    < 0 => Color.FromArgb(60, 88, 91, 112), // Clear zone
                     _ => Color.FromArgb(60, 255, 255, 255),
                 };
                 var zoneBrush = new SolidColorBrush(zoneColor);
@@ -2021,6 +2022,8 @@ private void PaintZoneAt(MapPosition center, int zoneFlag, Dictionary<MapPositio
 
         // All zone flags that we toggle
         const uint allZoneFlags = 0x01 | 0x02 | 0x04 | 0x08;
+        // Negative values (e.g. -1) mean "clear all zones"
+        uint flagToApply = zoneFlag < 0 ? 0u : (uint)zoneFlag;
         var tiles = GetBrushTiles(center);
 
         foreach (var pos in tiles)
@@ -2030,13 +2033,13 @@ private void PaintZoneAt(MapPosition center, int zoneFlag, Dictionary<MapPositio
 
             if (!_mapData.Tiles.TryGetValue(pos, out var tile))
             {
-                if (zoneFlag == 0) continue; // clearing zone on non-existent tile is a no-op
+                if (flagToApply == 0) continue; // clearing zone on non-existent tile is a no-op
                 tile = new MapTile { Position = pos };
                 _mapData.Tiles[pos] = tile;
             }
 
             // Clear all zone flags, then set the requested one
-            tile.Flags = (uint)((tile.Flags & ~allZoneFlags) | (uint)zoneFlag);
+            tile.Flags = (tile.Flags & ~allZoneFlags) | flagToApply;
         }
     }
 
@@ -2335,6 +2338,8 @@ private void FillZoneArea(MapPosition min, MapPosition max, int zoneFlag)
         if (_mapData == null) return;
 
         const uint allZoneFlags = 0x01 | 0x02 | 0x04 | 0x08;
+        // Negative values (e.g. -1) mean "clear all zones"
+        uint flagToApply = zoneFlag < 0 ? 0u : (uint)zoneFlag;
         var positions = new List<MapPosition>();
         for (int y = min.Y; y <= max.Y; y++)
             for (int x = min.X; x <= max.X; x++)
@@ -2346,11 +2351,11 @@ private void FillZoneArea(MapPosition min, MapPosition max, int zoneFlag)
         {
             if (!_mapData.Tiles.TryGetValue(pos, out var tile))
             {
-                if (zoneFlag == 0) continue;
+                if (flagToApply == 0) continue;
                 tile = new MapTile { Position = pos };
                 _mapData.Tiles[pos] = tile;
             }
-            tile.Flags = (uint)((tile.Flags & ~allZoneFlags) | (uint)zoneFlag);
+            tile.Flags = (tile.Flags & ~allZoneFlags) | flagToApply;
         }
 
         int count = positions.Count;
@@ -2934,7 +2939,7 @@ protected override void OnPointerPressed(PointerPressedEventArgs e)
                 e.Handled = true;
             }
             // 4) Zone brush (paint tile flags)
-            else if (ActiveZoneBrush >= 0 && ActiveZoneBrush != 0)
+            else if (ActiveZoneBrush != 0)
             {
                 _paintUndoSnapshot = new Dictionary<MapPosition, MapTile?>();
                 PaintZoneAt(tilePos, ActiveZoneBrush, _paintUndoSnapshot);
@@ -3203,7 +3208,7 @@ protected override void OnPointerReleased(PointerReleasedEventArgs e)
                 FillRemoveBordersArea(minPos, maxPos);
                 e.Handled = true;
             }
-            else if (ActiveZoneBrush > 0)
+            else if (ActiveZoneBrush != 0)
             {
                 FillZoneArea(minPos, maxPos, ActiveZoneBrush);
                 e.Handled = true;

src/App/MainWindow.axaml

@@ -533,6 +533,17 @@
                               Margin="2,0,0,0">
                   <i:Icon Value="fa-solid fa-table-cells" FontSize="11"/>
                 </ToggleButton>
+                <Border DockPanel.Dock="Right" Background="#181825" CornerRadius="4" Padding="2,0" Margin="4,0,0,0"
+                        ToolTip.Tip="{Binding SpriteZoom, StringFormat='Zoom {0}x'}">
+                  <StackPanel Orientation="Horizontal" Spacing="3" VerticalAlignment="Center">
+                    <i:Icon Value="fa-solid fa-magnifying-glass" FontSize="10" Foreground="#585b70"/>
+                    <Slider Minimum="1" Maximum="6" Value="{Binding SpriteZoom}"
+                            IsSnapToTickEnabled="True" TickFrequency="1"
+                            Width="60" MinHeight="20" Padding="0"/>
+                    <TextBlock Text="{Binding SpriteZoom, StringFormat='{}{0}x'}" Foreground="#cba6f7"
+                               FontSize="10" FontWeight="Bold" VerticalAlignment="Center" MinWidth="18"/>
+                  </StackPanel>
+                </Border>
                 <ComboBox DockPanel.Dock="Right" ItemsSource="{Binding ClientCategoryOptions}"
                           SelectedItem="{Binding ClientCategoryFilter}"
                           FontSize="11" MinHeight="28" Padding="6,3" MinWidth="70" Margin="4,0,0,0"/>
@@ -643,11 +654,17 @@
                 </ListBox.Styles>
                 <ListBox.ItemTemplate>
                   <DataTemplate x:DataType="vm:ClientItemViewModel">
-                    <Grid ColumnDefinitions="38,*" Height="38" Margin="2,1">
-                      <Border Classes="clientSprBox" Background="#11111b" CornerRadius="4" Width="32" Height="32"
+                    <Grid ColumnDefinitions="Auto,*"
+                          Height="{Binding #ClientItemListBox.((vm:MainWindowViewModel)DataContext).SpriteRowHeight}"
+                          Margin="2,1">
+                      <Border Classes="clientSprBox" Background="#11111b" CornerRadius="4"
+                              Width="{Binding #ClientItemListBox.((vm:MainWindowViewModel)DataContext).SpriteImageSize}"
+                              Height="{Binding #ClientItemListBox.((vm:MainWindowViewModel)DataContext).SpriteImageSize}"
                               BorderThickness="3"
                               VerticalAlignment="Center" HorizontalAlignment="Center" ClipToBounds="True">
-                        <Image Source="{Binding Sprite}" Width="32" Height="32"
+                        <Image Source="{Binding Sprite}"
+                               Width="{Binding #ClientItemListBox.((vm:MainWindowViewModel)DataContext).SpriteImageSize}"
+                               Height="{Binding #ClientItemListBox.((vm:MainWindowViewModel)DataContext).SpriteImageSize}"
                                RenderOptions.BitmapInterpolationMode="None" Stretch="Uniform"/>
                       </Border>
                       <TextBlock Grid.Column="1" Text="{Binding Id}" Foreground="#cba6f7"
@@ -674,9 +691,13 @@
                 </ListBox.ItemsPanel>
                 <ListBox.ItemTemplate>
                   <DataTemplate x:DataType="vm:ClientItemViewModel">
-                    <Border Width="36" Height="36" Background="#11111b" CornerRadius="3" Margin="1"
+                    <Border Width="{Binding #ClientItemIconBox.((vm:MainWindowViewModel)DataContext).SpriteCellSize}"
+                            Height="{Binding #ClientItemIconBox.((vm:MainWindowViewModel)DataContext).SpriteCellSize}"
+                            Background="#11111b" CornerRadius="3" Margin="1"
                             ToolTip.Tip="{Binding Id}" Classes="clientSprBox">
-                      <Image Source="{Binding Sprite}" Width="32" Height="32"
+                      <Image Source="{Binding Sprite}"
+                             Width="{Binding #ClientItemIconBox.((vm:MainWindowViewModel)DataContext).SpriteImageSize}"
+                             Height="{Binding #ClientItemIconBox.((vm:MainWindowViewModel)DataContext).SpriteImageSize}"
                              RenderOptions.BitmapInterpolationMode="None" Stretch="Uniform"
                              HorizontalAlignment="Center" VerticalAlignment="Center"/>
                     </Border>
@@ -1960,7 +1981,7 @@
                       </StackPanel>
                     </Button>
                     <Button Classes="toolbar" Padding="5,2" ToolTip.Tip="Clear Zone"
-                            Tag="0" Click="OnZoneBrushClick">
+                            Tag="-1" Click="OnZoneBrushClick">
                       <i:Icon Value="fa-solid fa-xmark" FontSize="9" Foreground="#585b70"/>
                     </Button>
                   </StackPanel>

src/App/ViewModels/MainWindowViewModel.cs

@@ -302,6 +302,11 @@ private void LoadFromSession(SessionViewModel session)
         OnPropertyChanged(nameof(ClientCategoryFilter));
         #pragma warning restore MVVMTK0034
 
+        // Clear selections before clearing collections to avoid Avalonia SelectionModel
+        // referencing stale indices during CollectionChanged
+        SelectedItem = null;
+        SelectedClientItem = null;
+
         // Clear visible collections — they will be repopulated by the filters below
         Items.Clear();
         ClientItems.Clear();
@@ -3944,6 +3949,25 @@ public int ClientItemsPerPage
     [ObservableProperty] private bool _isPlayingAnimation;
     [ObservableProperty] private bool _isClientIconView;
 
+    private int _spriteZoom = 1;
+    public int SpriteZoom
+    {
+        get => _spriteZoom;
+        set
+        {
+            value = Math.Clamp(value, 1, 6);
+            if (SetProperty(ref _spriteZoom, value))
+            {
+                OnPropertyChanged(nameof(SpriteImageSize));
+                OnPropertyChanged(nameof(SpriteCellSize));
+                OnPropertyChanged(nameof(SpriteRowHeight));
+            }
+        }
+    }
+    public int SpriteImageSize => 32 * _spriteZoom;
+    public int SpriteCellSize => 32 * _spriteZoom + 4;
+    public int SpriteRowHeight => 32 * _spriteZoom + 6;
+
     public ObservableCollection<SpriteViewModel> FilmstripFrames { get; } = [];
     public bool HasAnimation => (CurrentFrameGroup?.Frames ?? 1) > 1;
     public bool HasMultipleGroups => (_currentCompositionThing?.FrameGroups.Length ?? 1) > 1;
@@ -4430,7 +4454,7 @@ public void OpenOtbItemEditor()
 
     partial void OnCompositionFrameChanged(int value) { OnPropertyChanged(nameof(CompositionFrameLabel)); ReloadCompositionGridOnly(); }
     partial void OnCompositionLayerChanged(int value) { OnPropertyChanged(nameof(CompositionLayerLabel)); ReloadComposition(); }
-    partial void OnCompositionPatternXChanged(int value) { OnPropertyChanged(nameof(CompositionPatternXLabel)); OnPropertyChanged(nameof(DirectionLabel)); ReloadComposition(); }
+    partial void OnCompositionPatternXChanged(int value) { OnPropertyChanged(nameof(CompositionPatternXLabel)); OnPropertyChanged(nameof(DirectionLabel)); _appSettings.PreferredDirection = value; _appSettings.Save(); ReloadComposition(); }
     partial void OnCompositionPatternYChanged(int value) { OnPropertyChanged(nameof(CompositionPatternYLabel)); ReloadComposition(); }
     partial void OnCompositionPatternZChanged(int value) => ReloadComposition();
     partial void OnCompositionFrameGroupIndexChanged(int value) { NotifyAllCompositionLabels(); ReloadComposition(); }
@@ -4868,6 +4892,25 @@ private async Task LoadSessionFiles(SessionViewModel session)
             if (!string.IsNullOrEmpty(session.MapFilePath) && File.Exists(session.MapFilePath))
             {
                 session.MapData = OtbmFile.Load(session.MapFilePath);
+
+                // Load external spawn/house files so they are not lost on save
+                var mapDir = Path.GetDirectoryName(session.MapFilePath) ?? ".";
+
+                if (!string.IsNullOrEmpty(session.MapData.SpawnFile))
+                {
+                    var spawnPath = Path.Combine(mapDir, session.MapData.SpawnFile);
+                    var spawns = SpawnHouseXml.LoadSpawns(spawnPath);
+                    session.MapData.Spawns.Clear();
+                    session.MapData.Spawns.AddRange(spawns);
+                }
+
+                if (!string.IsNullOrEmpty(session.MapData.HouseFile))
+                {
+                    var housePath = Path.Combine(mapDir, session.MapData.HouseFile);
+                    var houses = SpawnHouseXml.LoadHouses(housePath);
+                    session.MapData.Houses.Clear();
+                    session.MapData.Houses.AddRange(houses);
+                }
             }
 
             session.UpdateName();
@@ -5901,10 +5944,11 @@ private void LoadComposition(DatThingType thing)
         CompositionFrameGroupIndex = 0;
         CompositionFrame = 0;
         CompositionLayer = 0;
-        CompositionPatternX = 0;
+        CompositionPatternX = _appSettings.PreferredDirection;
         CompositionPatternY = 0;
         CompositionPatternZ = 0;
         NotifyAllCompositionLabels();
+        ClampNavigationIndices();
         BuildCompositionGrid();
         BuildFilmstrip();
 
@@ -6053,9 +6097,10 @@ private void ResetThing()
         CompositionFrameGroupIndex = 0;
         CompositionFrame = 0;
         CompositionLayer = 0;
-        CompositionPatternX = 0;
+        CompositionPatternX = _appSettings.PreferredDirection;
         CompositionPatternY = 0;
         CompositionPatternZ = 0;
+        ClampNavigationIndices();
         NotifyAllCompositionLabels();
         OnPropertyChanged(nameof(IsItemSelected));
         OnPropertyChanged(nameof(IsOutfitSelected));

src/App/crash.log

@@ -117,3 +117,34 @@
    at Avalonia.Controls.ApplicationLifetimes.ClassicDesktopStyleApplicationLifetime.Start(String[] args)
    at Avalonia.ClassicDesktopStyleApplicationLifetimeExtensions.StartWithClassicDesktopLifetime(AppBuilder builder, String[] args, Action`1 lifetimeBuilder)
    at AssetsAndMapEditor.App.Program.Main(String[] args) in /Users/brewertonsantos/dev/pokeorigins-tibia/assets-and-map-editor/src/App/Program.cs:line 25
+[2026-04-08 10:39:14] UNHANDLED: System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection. (Parameter 'index')
+   at System.Collections.ObjectModel.Collection`1.System.Collections.IList.get_Item(Int32 index)
+   at Avalonia.Controls.Selection.SelectedItems`1.GetEnumerator()+MoveNext()
+   at System.Linq.Enumerable.<ToArray>g__EnumerableToArray|324_0[TSource](IEnumerable`1 source)
+   at Avalonia.Controls.Primitives.SelectingItemsControl.OnSelectionModelSelectionChanged(Object sender, SelectionModelSelectionChangedEventArgs e)
+   at Avalonia.Controls.Selection.SelectionModel`1.CommitOperation(Operation operation, Boolean raisePropertyChanged)
+   at Avalonia.Controls.Utils.CollectionChangedEventManager.Entry.<Avalonia.Utilities.IWeakEventSubscriber<System.Collections.Specialized.NotifyCollectionChangedEventArgs>.OnEvent>g__Notify|6_0(INotifyCollectionChanged incc, NotifyCollectionChangedEventArgs args, WeakReference`1[] listeners)
+   at Avalonia.Utilities.WeakEvent`2.Subscription.OnEvent(Object sender, TEventArgs eventArgs)
+   at System.Collections.ObjectModel.Collection`1.Clear()
+   at AssetsAndMapEditor.App.ViewModels.MainWindowViewModel.LoadFromSession(SessionViewModel session) in /Users/brewertonsantos/dev/pokeorigins-tibia/assets-and-map-editor/src/App/ViewModels/MainWindowViewModel.cs:line 307
+   at AssetsAndMapEditor.App.ViewModels.MainWindowViewModel.SwitchToSession(SessionViewModel session) in /Users/brewertonsantos/dev/pokeorigins-tibia/assets-and-map-editor/src/App/ViewModels/MainWindowViewModel.cs:line 201
+   at AssetsAndMapEditor.App.MainWindow.OnSessionTabPressed(Object sender, PointerPressedEventArgs e) in /Users/brewertonsantos/dev/pokeorigins-tibia/assets-and-map-editor/src/App/MainWindow.axaml.cs:line 242
+   at Avalonia.Interactivity.EventRoute.RaiseEventImpl(RoutedEventArgs e)
+   at Avalonia.Interactivity.EventRoute.RaiseEvent(Interactive source, RoutedEventArgs e)
+   at Avalonia.Interactivity.Interactive.RaiseEvent(RoutedEventArgs e)
+   at Avalonia.Input.MouseDevice.MouseDown(IMouseDevice device, UInt64 timestamp, IInputElement root, Point p, PointerPointProperties properties, KeyModifiers inputModifiers, IInputElement hitTest)
+   at Avalonia.Input.MouseDevice.ProcessRawEvent(RawPointerEventArgs e)
+   at Avalonia.Controls.TopLevel.<>c.<HandleInput>b__150_0(Object state)
+   at Avalonia.Threading.Dispatcher.Send(SendOrPostCallback action, Object arg, Nullable`1 priority)
+   at Avalonia.Native.TopLevelImpl.RawMouseEvent(AvnRawMouseEventType type, AvnPointerDeviceType deviceType, UInt64 timeStamp, AvnInputModifiers modifiers, AvnPoint point, AvnVector delta, Single pressure, Single xTilt, Single yTilt)
+   at Avalonia.Native.Interop.Impl.__MicroComIAvnTopLevelEventsVTable.RawMouseEvent(Void* this, AvnRawMouseEventType type, AvnPointerDeviceType deviceType, UInt64 timeStamp, AvnInputModifiers modifiers, AvnPoint point, AvnVector delta, Single pressure, Single xTilt, Single yTilt)
+--- End of stack trace from previous location ---
+   at Avalonia.Native.DispatcherImpl.RunLoop(CancellationToken token)
+   at Avalonia.Native.DispatcherImpl.RunLoop(CancellationToken token)
+   at Avalonia.Threading.DispatcherFrame.Run(IControlledDispatcherImpl impl)
+   at Avalonia.Threading.Dispatcher.PushFrame(DispatcherFrame frame)
+   at Avalonia.Threading.Dispatcher.MainLoop(CancellationToken cancellationToken)
+   at Avalonia.Controls.ApplicationLifetimes.ClassicDesktopStyleApplicationLifetime.StartCore(String[] args)
+   at Avalonia.Controls.ApplicationLifetimes.ClassicDesktopStyleApplicationLifetime.Start(String[] args)
+   at Avalonia.ClassicDesktopStyleApplicationLifetimeExtensions.StartWithClassicDesktopLifetime(AppBuilder builder, String[] args, Action`1 lifetimeBuilder)
+   at AssetsAndMapEditor.App.Program.Main(String[] args) in /Users/brewertonsantos/dev/pokeorigins-tibia/assets-and-map-editor/src/App/Program.cs:line 25