Layer merging

src/PixiEditor/ViewModels/SubViewModels/Document/DocumentStructureViewModel.cs

@@ -41,6 +41,18 @@ internal class DocumentStructureViewModel
         return null;
     }
 
+    public (StructureMemberViewModel?, FolderViewModel?) FindChildAndParent(Guid childGuid)
+    {
+        List<StructureMemberViewModel>? path = FindPath(childGuid);
+        return path.Count switch
+        {
+            0 => (null, null),
+            1 => (path[0], null),
+            >= 2 => (path[0], (FolderViewModel)path[1]),
+            _ => (null, null),
+        }; 
+    }
+
     public (StructureMemberViewModel, FolderViewModel) FindChildAndParentOrThrow(Guid childGuid)
     {
         List<StructureMemberViewModel>? path = FindPath(childGuid);

src/PixiEditor/ViewModels/SubViewModels/Document/DocumentViewModel.cs

@@ -4,6 +4,7 @@ using System.Windows.Media.Imaging;
 using ChunkyImageLib;
 using ChunkyImageLib.DataHolders;
 using ChunkyImageLib.Operations;
+using PixiEditor.ChangeableDocument.Actions.Undo;
 using PixiEditor.ChangeableDocument.Changeables.Interfaces;
 using PixiEditor.ChangeableDocument.Enums;
 using PixiEditor.ChangeableDocument.Rendering;
@@ -289,6 +290,25 @@ internal class DocumentViewModel : NotifyableObject
             return;
         Helpers.StructureHelper.TryMoveStructureMember(memberToMove, memberToMoveIntoOrNextTo, placement);
     }
+    public void MergeStructureMembers(IReadOnlyList<Guid> members)
+    {
+        if (Helpers.ChangeController.IsChangeActive || members.Count < 2)
+            return;
+        var (child, parent) = StructureViewModel.FindChildAndParent(members[0]);
+        if (child is null || parent is null)
+            return;
+        int index = parent.Children.IndexOf(child);
+        Guid newGuid = Guid.NewGuid();
+
+        //make a new layer, put combined image onto it, delete layers that were merged
+        Helpers.ActionAccumulator.AddActions(
+            new CreateStructureMember_Action(parent.GuidValue, newGuid, index, StructureMemberType.Layer),
+            new StructureMemberName_Action(newGuid, child.NameBindable),
+            new CombineStructureMembersOnto_Action(members.ToHashSet(), newGuid));
+        foreach (var member in members)
+            Helpers.ActionAccumulator.AddActions(new DeleteStructureMember_Action(member));
+        Helpers.ActionAccumulator.AddActions(new ChangeBoundary_Action());
+    }
 
     public SKColor PickColor(VecI pos, bool fromAllLayers)
     {

src/PixiEditor/ViewModels/SubViewModels/Main/LayersViewModel.cs

@@ -44,8 +44,8 @@ internal class LayersViewModel : SubViewModel<ViewModelMain>
         member.Document.DeleteStructureMember(member.GuidValue);
     }
 
-    [Evaluator.CanExecute("PixiEditor.Layer.CanDeleteAllSelected")]
-    public bool CanDeleteAllSelected(object parameter)
+    [Evaluator.CanExecute("PixiEditor.Layer.HasSelectedMembers")]
+    public bool HasSelectedMembers(object parameter)
     {
         var doc = Owner.DocumentManagerSubViewModel.ActiveDocument;
         if (doc is null)
@@ -53,17 +53,39 @@ internal class LayersViewModel : SubViewModel<ViewModelMain>
         return doc.SelectedStructureMember is not null || doc.SoftSelectedStructureMembers.Count > 0;
     }
 
-    [Command.Basic("PixiEditor.Layer.DeleteAllSelected", "Delete all selected layers/folders", "Delete all selected layers and/or folders", CanExecute = "PixiEditor.Layer.CanDeleteAllSelected")]
-    public void DeleteAllSelected(object parameter)
+    [Evaluator.CanExecute("PixiEditor.Layer.HasMultipleSelectedMembers")]
+    public bool HasMultipleSelectedMembers(object parameter)
     {
         var doc = Owner.DocumentManagerSubViewModel.ActiveDocument;
         if (doc is null)
-            return;
+            return false;
+        int count = doc.SoftSelectedStructureMembers.Count;
+        if (doc.SelectedStructureMember is not null)
+            count++;
+        return count > 1;
+    }
+
+    private List<Guid> GetSelected()
+    {
         List<Guid> membersToDelete = new();
+        var doc = Owner.DocumentManagerSubViewModel.ActiveDocument;
+        if (doc is null)
+            return membersToDelete;
         if (doc.SelectedStructureMember is not null)
             membersToDelete.Add(doc.SelectedStructureMember.GuidValue);
         membersToDelete.AddRange(doc.SoftSelectedStructureMembers.Select(static member => member.GuidValue));
-        doc.DeleteStructureMembers(membersToDelete);
+        return membersToDelete;
+    }
+
+    [Command.Basic("PixiEditor.Layer.DeleteAllSelected", "Delete all selected layers/folders", "Delete all selected layers and/or folders", CanExecute = "PixiEditor.Layer.HasSelectedMembers")]
+    public void DeleteAllSelected(object parameter)
+    {
+        var doc = Owner.DocumentManagerSubViewModel.ActiveDocument;
+        if (doc is null)
+            return;
+        var selected = GetSelected();
+        if (selected.Count > 0)
+            doc.DeleteStructureMembers(selected);
     }
 
     [Command.Basic("PixiEditor.Layer.NewFolder", "New Folder", "Create new folder", CanExecute = "PixiEditor.Layer.CanCreateNewMember")]
@@ -129,7 +151,7 @@ internal class LayersViewModel : SubViewModel<ViewModelMain>
         return false;
     }
 
-    private bool CanMoveSelectedMember(bool upwards)
+    private bool HasSelectedMember(bool above)
     {
         var doc = Owner.DocumentManagerSubViewModel.ActiveDocument;
         var member = doc?.SelectedStructureMember;
@@ -140,9 +162,9 @@ internal class LayersViewModel : SubViewModel<ViewModelMain>
             return false;
         var parent = (FolderViewModel)path[1];
         int index = parent.Children.IndexOf(path[0]);
-        if (upwards && index == parent.Children.Count - 1)
+        if (above && index == parent.Children.Count - 1)
             return false;
-        if (!upwards && index == 0)
+        if (!above && index == 0)
             return false;
         return true;
     }
@@ -172,43 +194,48 @@ internal class LayersViewModel : SubViewModel<ViewModelMain>
         }
     }
 
-    [Evaluator.CanExecute("PixiEditor.Layer.CanMoveSelectedMemberUpwards")]
-    public bool CanMoveSelectedMemberUpwards(object property) => CanMoveSelectedMember(true);
-    [Evaluator.CanExecute("PixiEditor.Layer.CanMoveSelectedMemberDownwards")]
-    public bool CanMoveSelectedMemberDownwards(object property) => CanMoveSelectedMember(false);
+    [Evaluator.CanExecute("PixiEditor.Layer.HasMemberAbove")]
+    public bool HasMemberAbove(object property) => HasSelectedMember(true);
+    [Evaluator.CanExecute("PixiEditor.Layer.HasMemberBelow")]
+    public bool HasMemberBelow(object property) => HasSelectedMember(false);
 
-    [Command.Basic("PixiEditor.Layer.MoveSelectedMemberUpwards", "Move selected layer or folder upwards", "Move selected layer or folder upwards", CanExecute = "PixiEditor.Layer.CanMoveSelectedMemberUpwards")]
+    [Command.Basic("PixiEditor.Layer.MoveSelectedMemberUpwards", "Move selected layer or folder upwards", "Move selected layer or folder upwards", CanExecute = "PixiEditor.Layer.HasMemberAbove")]
     public void MoveSelectedMemberUpwards(object parameter) => MoveSelectedMember(true);
-    [Command.Basic("PixiEditor.Layer.MoveSelectedMemberDownwards", "Move selected layer or folder downwards", "Move selected layer or folder downwards", CanExecute = "PixiEditor.Layer.CanMoveSelectedMemberDownwards")]
+    [Command.Basic("PixiEditor.Layer.MoveSelectedMemberDownwards", "Move selected layer or folder downwards", "Move selected layer or folder downwards", CanExecute = "PixiEditor.Layer.HasMemberBelow")]
     public void MoveSelectedMemberDownwards(object parameter) => MoveSelectedMember(false);
 
-    public bool CanMergeSelected(object obj)
-    {
-        return false;
-    }
-
+    [Command.Basic("PixiEditor.Layer.MergeSelected", "Merge all selected layers/folders", "Merge all selected layers/folders", CanExecute = "PixiEditor.Layer.HasMultipleSelectedMembers")]
     public void MergeSelected(object parameter)
     {
-
-    }
-
-    public bool CanMergeWithAbove(object property)
-    {
-        return false;
-    }
-
-    public void MergeWithAbove(object parameter)
-    {
-
+        var doc = Owner.DocumentManagerSubViewModel.ActiveDocument;
+        if (doc is null)
+            return;
+        var selected = GetSelected();
+        if (selected.Count == 0)
+            return;
+        doc.MergeStructureMembers(selected);
     }
 
-    public bool CanMergeWithBelow(object property)
+    public void MergeSelectedWith(bool above)
     {
-        return false;
+        var doc = Owner.DocumentManagerSubViewModel.ActiveDocument;
+        var member = doc?.SelectedStructureMember;
+        if (doc is null || member is null)
+            return;
+        var (child, parent) = doc.StructureViewModel.FindChildAndParent(member.GuidValue);
+        if (child is null || parent is null)
+            return;
+        int index = parent.Children.IndexOf(child);
+        if (!above && index == 0)
+            return;
+        if (above && index == parent.Children.Count - 1)
+            return;
+        doc.MergeStructureMembers(new List<Guid> { member.GuidValue, above ? parent.Children[index + 1].GuidValue : parent.Children[index - 1].GuidValue });
     }
 
-    public void MergeWithBelow(object parameter)
-    {
+    [Command.Basic("PixiEditor.Layer.MergeWithAbove", "Merge selected layer with the one above it", "Merge selected layer with the one above it", CanExecute = "PixiEditor.Layer.HasMemberAbove")]
+    public void MergeWithAbove(object parameter) => MergeSelectedWith(true);
 
-    }
+    [Command.Basic("PixiEditor.Layer.MergeWithBelow", "Merge selected layer with the one below it", "Merge selected layer with the one below it", CanExecute = "PixiEditor.Layer.HasMemberBelow")]
+    public void MergeWithBelow(object parameter) => MergeSelectedWith(false);
 }

src/PixiEditor/Views/UserControls/Layers/LayerControl.xaml

@@ -74,22 +74,12 @@
                 </MenuItem>
                 <MenuItem Header="Delete" Command="{cmds:Command PixiEditor.Layer.DeleteAllSelected}"/>
                 <MenuItem Header="Rename" Click="RenameMenuItem_Click"/>
-
                 <MenuItem Header="Move upwards" Command="{cmds:Command PixiEditor.Layer.MoveSelectedMemberUpwards}"/>
                 <MenuItem Header="Move downwards" Command="{cmds:Command PixiEditor.Layer.MoveSelectedMemberDownwards}"/>
-
                 <Separator/>
-                <MenuItem Header="Merge selected"
-                                     Command="{Binding PlacementTarget.Tag.LayerCommandsViewModel.MergeSelectedCommand, 
-                                            RelativeSource={RelativeSource AncestorType=ContextMenu}}"/>
-                <MenuItem Header="Merge with above"
-                                     Command="{Binding PlacementTarget.Tag.LayerCommandsViewModel.MergeWithAboveCommand, 
-                                            RelativeSource={RelativeSource AncestorType=ContextMenu}}" CommandParameter="{Binding PlacementTarget.Tag.ContainerIndex, RelativeSource={RelativeSource AncestorType=ContextMenu}}">
-                </MenuItem>
-                <MenuItem Header="Merge with below"
-                                    Command="{Binding PlacementTarget.Tag.LayerCommandsViewModel.MergeWithBelowCommand, 
-                                            RelativeSource={RelativeSource AncestorType=ContextMenu}}" CommandParameter="{Binding PlacementTarget.Tag.ContainerIndex, RelativeSource={RelativeSource AncestorType=ContextMenu}}">
-                </MenuItem>
+                <MenuItem Header="Merge selected" Command="{cmds:Command PixiEditor.Layer.MergeSelected}"/>
+                <MenuItem Header="Merge with above" Command="{cmds:Command PixiEditor.Layer.MergeWithAbove}"/>
+                <MenuItem Header="Merge with below" Command="{cmds:Command PixiEditor.Layer.MergeWithBelow}"/>
             </ContextMenu>
         </Border.ContextMenu>
     </Border>