diff --git a/Minint.Core/Services/IImageEffectsService.cs b/Minint.Core/Services/IImageEffectsService.cs
new file mode 100644
index 0000000..570c6c2
--- /dev/null
+++ b/Minint.Core/Services/IImageEffectsService.cs
@@ -0,0 +1,18 @@
+using Minint.Core.Models;
+
+namespace Minint.Core.Services;
+
+public interface IImageEffectsService
+{
+    /// <summary>
+    /// Adjusts contrast of the document by transforming its palette colors.
+    /// <paramref name="factor"/> of 0 = all gray, 1 = no change, >1 = increased contrast.
+    /// </summary>
+    void ApplyContrast(MinintDocument doc, double factor);
+
+    /// <summary>
+    /// Converts the document to grayscale by transforming its palette colors
+    /// using the luminance formula: 0.299R + 0.587G + 0.114B.
+    /// </summary>
+    void ApplyGrayscale(MinintDocument doc);
+}
diff --git a/Minint.Core/Services/Impl/ImageEffectsService.cs b/Minint.Core/Services/Impl/ImageEffectsService.cs
new file mode 100644
index 0000000..67c25f6
--- /dev/null
+++ b/Minint.Core/Services/Impl/ImageEffectsService.cs
@@ -0,0 +1,38 @@
+using System;
+using Minint.Core.Models;
+
+namespace Minint.Core.Services.Impl;
+
+public sealed class ImageEffectsService : IImageEffectsService
+{
+    public void ApplyContrast(MinintDocument doc, double factor)
+    {
+        for (int i = 1; i < doc.Palette.Count; i++)
+        {
+            var c = doc.Palette[i];
+            doc.Palette[i] = new RgbaColor(
+                ContrastByte(c.R, factor),
+                ContrastByte(c.G, factor),
+                ContrastByte(c.B, factor),
+                c.A);
+        }
+        doc.InvalidatePaletteCache();
+    }
+
+    public void ApplyGrayscale(MinintDocument doc)
+    {
+        for (int i = 1; i < doc.Palette.Count; i++)
+        {
+            var c = doc.Palette[i];
+            byte gray = (byte)Math.Clamp((int)(0.299 * c.R + 0.587 * c.G + 0.114 * c.B + 0.5), 0, 255);
+            doc.Palette[i] = new RgbaColor(gray, gray, gray, c.A);
+        }
+        doc.InvalidatePaletteCache();
+    }
+
+    private static byte ContrastByte(byte value, double factor)
+    {
+        double v = ((value / 255.0) - 0.5) * factor + 0.5;
+        return (byte)Math.Clamp((int)(v * 255 + 0.5), 0, 255);
+    }
+}
diff --git a/Minint.Core/Services/Impl/PatternGenerator.cs b/Minint.Core/Services/Impl/PatternGenerator.cs
new file mode 100644
index 0000000..8561b47
--- /dev/null
+++ b/Minint.Core/Services/Impl/PatternGenerator.cs
@@ -0,0 +1,113 @@
+using System;
+using Minint.Core.Models;
+
+namespace Minint.Core.Services.Impl;
+
+public sealed class PatternGenerator : IPatternGenerator
+{
+    public MinintDocument Generate(PatternType type, int width, int height, RgbaColor[] colors, int param1, int param2 = 0)
+    {
+        ArgumentOutOfRangeException.ThrowIfLessThan(width, 1);
+        ArgumentOutOfRangeException.ThrowIfLessThan(height, 1);
+        if (colors.Length < 2)
+            throw new ArgumentException("At least two colors are required.", nameof(colors));
+
+        var doc = new MinintDocument($"Pattern ({type})");
+        var layer = new MinintLayer("Pattern", width * height);
+        doc.Layers.Add(layer);
+
+        int[] colorIndices = new int[colors.Length];
+        for (int i = 0; i < colors.Length; i++)
+            colorIndices[i] = doc.EnsureColorCached(colors[i]);
+
+        int cellSize = Math.Max(param1, 1);
+
+        switch (type)
+        {
+            case PatternType.Checkerboard:
+                FillCheckerboard(layer.Pixels, width, height, colorIndices, cellSize);
+                break;
+            case PatternType.HorizontalGradient:
+                FillGradient(layer.Pixels, width, height, colors[0], colors[1], doc, horizontal: true);
+                break;
+            case PatternType.VerticalGradient:
+                FillGradient(layer.Pixels, width, height, colors[0], colors[1], doc, horizontal: false);
+                break;
+            case PatternType.HorizontalStripes:
+                FillStripes(layer.Pixels, width, height, colorIndices, cellSize, horizontal: true);
+                break;
+            case PatternType.VerticalStripes:
+                FillStripes(layer.Pixels, width, height, colorIndices, cellSize, horizontal: false);
+                break;
+            case PatternType.ConcentricCircles:
+                FillCircles(layer.Pixels, width, height, colorIndices, cellSize);
+                break;
+            case PatternType.Tile:
+                FillTile(layer.Pixels, width, height, colorIndices, cellSize, Math.Max(param2, 1));
+                break;
+        }
+
+        return doc;
+    }
+
+    private static void FillCheckerboard(int[] pixels, int w, int h, int[] ci, int cell)
+    {
+        for (int y = 0; y < h; y++)
+            for (int x = 0; x < w; x++)
+                pixels[y * w + x] = ci[((x / cell) + (y / cell)) % 2 == 0 ? 0 : 1];
+    }
+
+    private static void FillGradient(int[] pixels, int w, int h, RgbaColor c0, RgbaColor c1,
+                                      MinintDocument doc, bool horizontal)
+    {
+        int steps = horizontal ? w : h;
+        for (int s = 0; s < steps; s++)
+        {
+            double t = steps > 1 ? (double)s / (steps - 1) : 0;
+            var c = new RgbaColor(
+                Lerp(c0.R, c1.R, t), Lerp(c0.G, c1.G, t),
+                Lerp(c0.B, c1.B, t), Lerp(c0.A, c1.A, t));
+            int idx = doc.EnsureColorCached(c);
+            if (horizontal)
+                for (int y = 0; y < h; y++) pixels[y * w + s] = idx;
+            else
+                for (int x = 0; x < w; x++) pixels[s * w + x] = idx;
+        }
+    }
+
+    private static void FillStripes(int[] pixels, int w, int h, int[] ci, int stripe, bool horizontal)
+    {
+        for (int y = 0; y < h; y++)
+            for (int x = 0; x < w; x++)
+            {
+                int coord = horizontal ? y : x;
+                pixels[y * w + x] = ci[(coord / stripe) % ci.Length];
+            }
+    }
+
+    private static void FillCircles(int[] pixels, int w, int h, int[] ci, int ringWidth)
+    {
+        double cx = (w - 1) / 2.0, cy = (h - 1) / 2.0;
+        for (int y = 0; y < h; y++)
+            for (int x = 0; x < w; x++)
+            {
+                double dist = Math.Sqrt((x - cx) * (x - cx) + (y - cy) * (y - cy));
+                int ring = (int)(dist / ringWidth);
+                pixels[y * w + x] = ci[ring % ci.Length];
+            }
+    }
+
+    private static void FillTile(int[] pixels, int w, int h, int[] ci, int tileW, int tileH)
+    {
+        for (int y = 0; y < h; y++)
+            for (int x = 0; x < w; x++)
+            {
+                int tx = (x / tileW) % ci.Length;
+                int ty = (y / tileH) % ci.Length;
+                pixels[y * w + x] = ci[(tx + ty) % ci.Length];
+            }
+    }
+
+    private static byte Lerp(byte a, byte b, double t)
+        => (byte)Math.Clamp((int)(a + (b - a) * t + 0.5), 0, 255);
+}
diff --git a/Minint/Controls/PixelCanvas.cs b/Minint/Controls/PixelCanvas.cs
index 9023710..9ca6b70 100644
--- a/Minint/Controls/PixelCanvas.cs
+++ b/Minint/Controls/PixelCanvas.cs
@@ -56,7 +56,10 @@ public class PixelCanvas : Control
     private Point _panStart;
     private double _panStartOffsetX, _panStartOffsetY;
     private bool _viewportInitialized;
+    private int _lastBitmapWidth;
+    private int _lastBitmapHeight;
     private (int X, int Y)? _lastCursorPixel;
+    private Point? _lastScreenPos;
 
     private ScrollBar? _hScrollBar;
     private ScrollBar? _vScrollBar;
@@ -248,6 +251,7 @@ public class PixelCanvas : Control
         if (_suppressScrollSync) return;
         var (imgW, imgH) = GetImageSize();
         _viewport.SetOffset(-e.NewValue, _viewport.OffsetY, imgW, imgH, Bounds.Width, Bounds.Height);
+        RecalcCursorPixel();
         InvalidateVisual();
     }
 
@@ -256,6 +260,7 @@ public class PixelCanvas : Control
         if (_suppressScrollSync) return;
         var (imgW, imgH) = GetImageSize();
         _viewport.SetOffset(_viewport.OffsetX, -e.NewValue, imgW, imgH, Bounds.Width, Bounds.Height);
+        RecalcCursorPixel();
         InvalidateVisual();
     }
 
@@ -279,6 +284,20 @@ public class PixelCanvas : Control
         return (px, py);
     }
 
+    /// <summary>
+    /// Recalculates the pixel coordinate under the cursor after a viewport change.
+    /// </summary>
+    private void RecalcCursorPixel()
+    {
+        if (_lastScreenPos is null) return;
+        var pixel = ScreenToPixelClamped(_lastScreenPos.Value);
+        if (pixel != _lastCursorPixel)
+        {
+            _lastCursorPixel = pixel;
+            CursorPixelChanged?.Invoke(pixel);
+        }
+    }
+
     protected override void OnPointerWheelChanged(PointerWheelEventArgs e)
     {
         base.OnPointerWheelChanged(e);
@@ -305,6 +324,7 @@ public class PixelCanvas : Control
             _viewport.Pan(dx, dy, imgW, imgH, Bounds.Width, Bounds.Height);
         }
 
+        RecalcCursorPixel();
         InvalidateVisual();
         e.Handled = true;
     }
@@ -338,6 +358,7 @@ public class PixelCanvas : Control
     {
         base.OnPointerMoved(e);
         var pos = e.GetPosition(this);
+        _lastScreenPos = pos;
 
         if (_isPanning)
         {
@@ -346,12 +367,12 @@ public class PixelCanvas : Control
                 _panStartOffsetX + (pos.X - _panStart.X),
                 _panStartOffsetY + (pos.Y - _panStart.Y),
                 imgW, imgH, Bounds.Width, Bounds.Height);
+            RecalcCursorPixel();
             InvalidateVisual();
             e.Handled = true;
             return;
         }
 
-        // Update preview cursor position
         var pixel = ScreenToPixelClamped(pos);
         if (pixel != _lastCursorPixel)
         {
@@ -386,6 +407,7 @@ public class PixelCanvas : Control
     protected override void OnPointerExited(PointerEventArgs e)
     {
         base.OnPointerExited(e);
+        _lastScreenPos = null;
         if (_lastCursorPixel is not null)
         {
             _lastCursorPixel = null;
@@ -400,6 +422,16 @@ public class PixelCanvas : Control
     {
         base.OnPropertyChanged(change);
         if (change.Property == SourceBitmapProperty)
-            _viewportInitialized = false;
+        {
+            var bmp = change.GetNewValue<WriteableBitmap?>();
+            int w = bmp?.PixelSize.Width ?? 0;
+            int h = bmp?.PixelSize.Height ?? 0;
+            if (w != _lastBitmapWidth || h != _lastBitmapHeight)
+            {
+                _lastBitmapWidth = w;
+                _lastBitmapHeight = h;
+                _viewportInitialized = false;
+            }
+        }
     }
 }
diff --git a/Minint/Program.cs b/Minint/Program.cs
index f061ea8..26aeca2 100644
--- a/Minint/Program.cs
+++ b/Minint/Program.cs
@@ -28,7 +28,8 @@ sealed class Program
         => AppBuilder.Configure<App>()
             .UsePlatformDetect()
             .WithInterFont()
-            .LogToTrace();
+            .LogToTrace()
+            .With(new X11PlatformOptions { OverlayPopups = true });
 
     // TODO: temporary tests — remove after verification stages.
 
diff --git a/Minint/ViewModels/EditorViewModel.cs b/Minint/ViewModels/EditorViewModel.cs
index dd21276..42c91be 100644
--- a/Minint/ViewModels/EditorViewModel.cs
+++ b/Minint/ViewModels/EditorViewModel.cs
@@ -113,6 +113,12 @@ public partial class EditorViewModel : ViewModelBase
         SyncLayersAndCanvas(doc);
     }
 
+    /// <summary>
+    /// Re-syncs the Documents observable collection after an external modification
+    /// to Container.Documents (e.g. pattern generation adding a document).
+    /// </summary>
+    public void SyncAfterExternalChange() => SyncDocumentsList();
+
     private void SyncDocumentsList()
     {
         Documents.Clear();
diff --git a/Minint/ViewModels/MainWindowViewModel.cs b/Minint/ViewModels/MainWindowViewModel.cs
index 887c256..15fed79 100644
--- a/Minint/ViewModels/MainWindowViewModel.cs
+++ b/Minint/ViewModels/MainWindowViewModel.cs
@@ -6,13 +6,19 @@ using Avalonia.Controls;
 using Avalonia.Platform.Storage;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
+using Minint.Core.Models;
+using Minint.Core.Services;
+using Minint.Core.Services.Impl;
 using Minint.Infrastructure.Serialization;
+using Minint.Views;
 
 namespace Minint.ViewModels;
 
 public partial class MainWindowViewModel : ViewModelBase
 {
     private readonly MinintSerializer _serializer = new();
+    private readonly IImageEffectsService _effects = new ImageEffectsService();
+    private readonly IPatternGenerator _patternGen = new PatternGenerator();
 
     private static readonly FilePickerFileType MinintFileType = new("Minint Files")
     {
@@ -25,11 +31,10 @@ public partial class MainWindowViewModel : ViewModelBase
     [ObservableProperty]
     private string _statusText = "Ready";
 
-    /// <summary>
-    /// Set by the view so that file dialogs can use the correct parent window.
-    /// </summary>
     public TopLevel? Owner { get; set; }
 
+    #region File commands
+
     [RelayCommand]
     private void NewFile()
     {
@@ -72,13 +77,9 @@ public partial class MainWindowViewModel : ViewModelBase
         if (Editor.Container is null) return;
 
         if (Editor.FilePath is not null)
-        {
             await SaveToPathAsync(Editor.FilePath);
-        }
         else
-        {
             await SaveFileAsAsync();
-        }
     }
 
     [RelayCommand]
@@ -121,4 +122,111 @@ public partial class MainWindowViewModel : ViewModelBase
             StatusText = $"Error saving file: {ex.Message}";
         }
     }
+
+    #endregion
+
+    #region Effects (A1, A2)
+
+    [RelayCommand]
+    private async Task ApplyContrastAsync()
+    {
+        if (Editor.ActiveDocument is null || Owner is not Window window) return;
+
+        var dialog = new ContrastDialog();
+        var result = await dialog.ShowDialog<bool?>(window);
+        if (result != true) return;
+
+        _effects.ApplyContrast(Editor.ActiveDocument, dialog.Factor);
+        Editor.RefreshCanvas();
+        StatusText = $"Contrast ×{dialog.Factor:F1} applied.";
+    }
+
+    [RelayCommand]
+    private void ApplyGrayscale()
+    {
+        if (Editor.ActiveDocument is null) return;
+
+        _effects.ApplyGrayscale(Editor.ActiveDocument);
+        Editor.RefreshCanvas();
+        StatusText = "Grayscale applied.";
+    }
+
+    #endregion
+
+    #region Copy fragment (A4)
+
+    [RelayCommand]
+    private async Task CopyFragmentAsync()
+    {
+        if (Editor.Container is null || Owner is not Window window) return;
+
+        var docs = Editor.Container.Documents;
+        if (docs.Count == 0) return;
+
+        var dialog = new CopyFragmentDialog(docs, Editor.Container.Width, Editor.Container.Height);
+        var result = await dialog.ShowDialog<bool?>(window);
+        if (result != true) return;
+
+        if (dialog.SourceDocument is null || dialog.DestDocument is null)
+        {
+            StatusText = "Copy failed: no document selected.";
+            return;
+        }
+        if (dialog.SourceLayerIndex < 0 || dialog.DestLayerIndex < 0)
+        {
+            StatusText = "Copy failed: no layer selected.";
+            return;
+        }
+
+        try
+        {
+            Editor.CopyFragment(
+                dialog.SourceDocument, dialog.SourceLayerIndex,
+                dialog.SourceX, dialog.SourceY,
+                dialog.FragmentWidth, dialog.FragmentHeight,
+                dialog.DestDocument, dialog.DestLayerIndex,
+                dialog.DestX, dialog.DestY);
+            StatusText = $"Copied {dialog.FragmentWidth}×{dialog.FragmentHeight} fragment.";
+        }
+        catch (Exception ex)
+        {
+            StatusText = $"Copy failed: {ex.Message}";
+        }
+    }
+
+    #endregion
+
+    #region Pattern generation (Б4)
+
+    [RelayCommand]
+    private async Task GeneratePatternAsync()
+    {
+        if (Editor.Container is null || Owner is not Window window) return;
+
+        var dialog = new PatternDialog();
+        var result = await dialog.ShowDialog<bool?>(window);
+        if (result != true) return;
+
+        try
+        {
+            var doc = _patternGen.Generate(
+                dialog.SelectedPattern,
+                Editor.Container.Width,
+                Editor.Container.Height,
+                [dialog.PatternColor1, dialog.PatternColor2],
+                dialog.PatternParam1,
+                dialog.PatternParam2);
+
+            Editor.Container.Documents.Add(doc);
+            Editor.SyncAfterExternalChange();
+            Editor.SelectDocument(doc);
+            StatusText = $"Pattern '{dialog.SelectedPattern}' generated.";
+        }
+        catch (Exception ex)
+        {
+            StatusText = $"Pattern generation failed: {ex.Message}";
+        }
+    }
+
+    #endregion
 }
diff --git a/Minint/Views/ContrastDialog.axaml b/Minint/Views/ContrastDialog.axaml
new file mode 100644
index 0000000..36b64b2
--- /dev/null
+++ b/Minint/Views/ContrastDialog.axaml
@@ -0,0 +1,20 @@
+<Window xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        x:Class="Minint.Views.ContrastDialog"
+        Title="Adjust Contrast"
+        Width="320"
+        WindowStartupLocation="CenterOwner"
+        CanResize="False"
+        SizeToContent="Height">
+    <StackPanel Margin="16" Spacing="10">
+        <TextBlock Text="Contrast factor (0 = gray, 1 = no change, >1 = more contrast):"/>
+        <Slider x:Name="FactorSlider" Minimum="0" Maximum="3" Value="1"
+                TickFrequency="0.1" IsSnapToTickEnabled="True"/>
+        <TextBlock x:Name="FactorLabel" Text="1.0" HorizontalAlignment="Center"/>
+
+        <StackPanel Orientation="Horizontal" HorizontalAlignment="Right" Spacing="8" Margin="0,8,0,0">
+            <Button Content="Apply" x:Name="OkButton" IsDefault="True" Padding="16,6"/>
+            <Button Content="Cancel" x:Name="CancelButton" IsCancel="True" Padding="16,6"/>
+        </StackPanel>
+    </StackPanel>
+</Window>
diff --git a/Minint/Views/ContrastDialog.axaml.cs b/Minint/Views/ContrastDialog.axaml.cs
new file mode 100644
index 0000000..86cb19f
--- /dev/null
+++ b/Minint/Views/ContrastDialog.axaml.cs
@@ -0,0 +1,24 @@
+using System;
+using Avalonia.Controls;
+using Avalonia.Interactivity;
+
+namespace Minint.Views;
+
+public partial class ContrastDialog : Window
+{
+    public double Factor => FactorSlider.Value;
+
+    public ContrastDialog()
+    {
+        InitializeComponent();
+
+        FactorSlider.PropertyChanged += (_, e) =>
+        {
+            if (e.Property == Slider.ValueProperty)
+                FactorLabel.Text = FactorSlider.Value.ToString("F1");
+        };
+
+        OkButton.Click += (_, _) => Close(true);
+        CancelButton.Click += (_, _) => Close(false);
+    }
+}
diff --git a/Minint/Views/CopyFragmentDialog.axaml b/Minint/Views/CopyFragmentDialog.axaml
new file mode 100644
index 0000000..6168d92
--- /dev/null
+++ b/Minint/Views/CopyFragmentDialog.axaml
@@ -0,0 +1,51 @@
+<Window xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        x:Class="Minint.Views.CopyFragmentDialog"
+        Title="Copy Fragment"
+        Width="380" Height="420"
+        WindowStartupLocation="CenterOwner"
+        CanResize="False"
+        SizeToContent="Height">
+    <StackPanel Margin="16" Spacing="8">
+        <TextBlock Text="Source" FontWeight="SemiBold"/>
+        <Grid ColumnDefinitions="100,*" RowDefinitions="Auto,Auto,Auto,Auto,Auto" RowSpacing="4" ColumnSpacing="8">
+            <TextBlock Grid.Row="0" Grid.Column="0" Text="Document:" VerticalAlignment="Center"/>
+            <ComboBox Grid.Row="0" Grid.Column="1" x:Name="SrcDocCombo"
+                      HorizontalAlignment="Stretch"/>
+            <TextBlock Grid.Row="1" Grid.Column="0" Text="Layer:" VerticalAlignment="Center"/>
+            <ComboBox Grid.Row="1" Grid.Column="1" x:Name="SrcLayerCombo"
+                      HorizontalAlignment="Stretch"/>
+            <TextBlock Grid.Row="2" Grid.Column="0" Text="X:" VerticalAlignment="Center"/>
+            <NumericUpDown Grid.Row="2" Grid.Column="1" x:Name="SrcX" Value="0" Minimum="0" FormatString="0"/>
+            <TextBlock Grid.Row="3" Grid.Column="0" Text="Y:" VerticalAlignment="Center"/>
+            <NumericUpDown Grid.Row="3" Grid.Column="1" x:Name="SrcY" Value="0" Minimum="0" FormatString="0"/>
+        </Grid>
+
+        <Grid ColumnDefinitions="100,*" RowDefinitions="Auto,Auto" RowSpacing="4" ColumnSpacing="8" Margin="0,4,0,0">
+            <TextBlock Grid.Row="0" Grid.Column="0" Text="Width:" VerticalAlignment="Center"/>
+            <NumericUpDown Grid.Row="0" Grid.Column="1" x:Name="RegionW" Value="16" Minimum="1" FormatString="0"/>
+            <TextBlock Grid.Row="1" Grid.Column="0" Text="Height:" VerticalAlignment="Center"/>
+            <NumericUpDown Grid.Row="1" Grid.Column="1" x:Name="RegionH" Value="16" Minimum="1" FormatString="0"/>
+        </Grid>
+
+        <Separator Margin="0,8"/>
+        <TextBlock Text="Destination" FontWeight="SemiBold"/>
+        <Grid ColumnDefinitions="100,*" RowDefinitions="Auto,Auto,Auto,Auto" RowSpacing="4" ColumnSpacing="8">
+            <TextBlock Grid.Row="0" Grid.Column="0" Text="Document:" VerticalAlignment="Center"/>
+            <ComboBox Grid.Row="0" Grid.Column="1" x:Name="DstDocCombo"
+                      HorizontalAlignment="Stretch"/>
+            <TextBlock Grid.Row="1" Grid.Column="0" Text="Layer:" VerticalAlignment="Center"/>
+            <ComboBox Grid.Row="1" Grid.Column="1" x:Name="DstLayerCombo"
+                      HorizontalAlignment="Stretch"/>
+            <TextBlock Grid.Row="2" Grid.Column="0" Text="X:" VerticalAlignment="Center"/>
+            <NumericUpDown Grid.Row="2" Grid.Column="1" x:Name="DstX" Value="0" Minimum="0" FormatString="0"/>
+            <TextBlock Grid.Row="3" Grid.Column="0" Text="Y:" VerticalAlignment="Center"/>
+            <NumericUpDown Grid.Row="3" Grid.Column="1" x:Name="DstY" Value="0" Minimum="0" FormatString="0"/>
+        </Grid>
+
+        <StackPanel Orientation="Horizontal" HorizontalAlignment="Right" Spacing="8" Margin="0,12,0,0">
+            <Button Content="Copy" x:Name="OkButton" IsDefault="True" Padding="16,6"/>
+            <Button Content="Cancel" x:Name="CancelButton" IsCancel="True" Padding="16,6"/>
+        </StackPanel>
+    </StackPanel>
+</Window>
diff --git a/Minint/Views/CopyFragmentDialog.axaml.cs b/Minint/Views/CopyFragmentDialog.axaml.cs
new file mode 100644
index 0000000..f9a1e6d
--- /dev/null
+++ b/Minint/Views/CopyFragmentDialog.axaml.cs
@@ -0,0 +1,91 @@
+using System;
+using System.Collections.Generic;
+using Avalonia.Controls;
+using Avalonia.Interactivity;
+using Minint.Core.Models;
+
+namespace Minint.Views;
+
+public partial class CopyFragmentDialog : Window
+{
+    private readonly List<MinintDocument> _documents;
+
+    public MinintDocument? SourceDocument => SrcDocCombo.SelectedItem as MinintDocument;
+    public int SourceLayerIndex => SrcLayerCombo.SelectedIndex;
+    public int SourceX => (int)(SrcX.Value ?? 0);
+    public int SourceY => (int)(SrcY.Value ?? 0);
+    public int FragmentWidth => (int)(RegionW.Value ?? 1);
+    public int FragmentHeight => (int)(RegionH.Value ?? 1);
+    public MinintDocument? DestDocument => DstDocCombo.SelectedItem as MinintDocument;
+    public int DestLayerIndex => DstLayerCombo.SelectedIndex;
+    public int DestX => (int)(DstX.Value ?? 0);
+    public int DestY => (int)(DstY.Value ?? 0);
+
+    public CopyFragmentDialog()
+    {
+        _documents = [];
+        InitializeComponent();
+    }
+
+    public CopyFragmentDialog(List<MinintDocument> documents, int maxW, int maxH) : this()
+    {
+        _documents = documents;
+
+        SrcDocCombo.ItemsSource = documents;
+        SrcDocCombo.DisplayMemberBinding = new Avalonia.Data.Binding("Name");
+        DstDocCombo.ItemsSource = documents;
+        DstDocCombo.DisplayMemberBinding = new Avalonia.Data.Binding("Name");
+
+        SrcX.Maximum = maxW - 1;
+        SrcY.Maximum = maxH - 1;
+        DstX.Maximum = maxW - 1;
+        DstY.Maximum = maxH - 1;
+        RegionW.Maximum = maxW;
+        RegionH.Maximum = maxH;
+
+        if (documents.Count > 0)
+        {
+            SrcDocCombo.SelectedIndex = 0;
+            DstDocCombo.SelectedIndex = documents.Count > 1 ? 1 : 0;
+        }
+
+        SrcDocCombo.SelectionChanged += (_, _) => UpdateSrcLayers();
+        DstDocCombo.SelectionChanged += (_, _) => UpdateDstLayers();
+
+        UpdateSrcLayers();
+        UpdateDstLayers();
+
+        OkButton.Click += OnOkClick;
+        CancelButton.Click += OnCancelClick;
+    }
+
+    private void UpdateSrcLayers()
+    {
+        if (SrcDocCombo.SelectedItem is MinintDocument doc)
+        {
+            SrcLayerCombo.ItemsSource = doc.Layers;
+            SrcLayerCombo.DisplayMemberBinding = new Avalonia.Data.Binding("Name");
+            if (doc.Layers.Count > 0) SrcLayerCombo.SelectedIndex = 0;
+        }
+    }
+
+    private void UpdateDstLayers()
+    {
+        if (DstDocCombo.SelectedItem is MinintDocument doc)
+        {
+            DstLayerCombo.ItemsSource = doc.Layers;
+            DstLayerCombo.DisplayMemberBinding = new Avalonia.Data.Binding("Name");
+            if (doc.Layers.Count > 0) DstLayerCombo.SelectedIndex = 0;
+        }
+    }
+
+    private void OnOkClick(object? sender, RoutedEventArgs e)
+    {
+        Close(true);
+    }
+
+    private void OnCancelClick(object? sender, RoutedEventArgs e)
+    {
+        Close(false);
+    }
+}
diff --git a/Minint/Views/MainWindow.axaml b/Minint/Views/MainWindow.axaml
index 2c7115d..7db5281 100644
--- a/Minint/Views/MainWindow.axaml
+++ b/Minint/Views/MainWindow.axaml
@@ -9,7 +9,8 @@
         x:DataType="vm:MainWindowViewModel"
         Icon="/Assets/avalonia-logo.ico"
         Title="{Binding Editor.Title}"
-        Width="1024" Height="700">
+        Width="1024" Height="700"
+        ToolTip.ShowDelay="400">
 
     <Design.DataContext>
         <vm:MainWindowViewModel/>
@@ -25,6 +26,19 @@
                 <MenuItem Header="_Save" Command="{Binding SaveFileCommand}" HotKey="Ctrl+S"/>
                 <MenuItem Header="Save _As…" Command="{Binding SaveFileAsCommand}" HotKey="Ctrl+Shift+S"/>
             </MenuItem>
+            <MenuItem Header="_Edit">
+                <MenuItem Header="Copy _Fragment…" Command="{Binding CopyFragmentCommand}"
+                          ToolTip.Tip="Copy a rectangular region between documents"/>
+            </MenuItem>
+            <MenuItem Header="_Image">
+                <MenuItem Header="Adjust _Contrast…" Command="{Binding ApplyContrastCommand}"
+                          ToolTip.Tip="Adjust contrast of the active document's palette"/>
+                <MenuItem Header="Convert to _Grayscale" Command="{Binding ApplyGrayscaleCommand}"
+                          ToolTip.Tip="Convert active document to grayscale"/>
+                <Separator/>
+                <MenuItem Header="Generate _Pattern…" Command="{Binding GeneratePatternCommand}"
+                          ToolTip.Tip="Generate a new document with a parametric pattern"/>
+            </MenuItem>
             <MenuItem Header="_View">
                 <MenuItem Header="Pixel _Grid" ToggleType="CheckBox"
                           IsChecked="{Binding Editor.ShowGrid}" HotKey="Ctrl+G"/>
@@ -83,13 +97,13 @@
                 <DockPanel>
                     <TextBlock DockPanel.Dock="Top" Text="Documents" FontWeight="SemiBold" Margin="0,0,0,4"/>
                     <StackPanel DockPanel.Dock="Bottom" Orientation="Horizontal" Spacing="2" Margin="0,4,0,0">
-                        <Button Content="+" ToolTip.Tip="Add document"
+                        <Button Content="+" ToolTip.Tip="Add a new document (frame)"
                                 Command="{Binding Editor.AddDocumentCommand}" Padding="6,2"/>
-                        <Button Content="−" ToolTip.Tip="Remove document"
+                        <Button Content="−" ToolTip.Tip="Remove selected document"
                                 Command="{Binding Editor.RemoveDocumentCommand}" Padding="6,2"/>
-                        <Button Content="▲" ToolTip.Tip="Move up"
+                        <Button Content="▲" ToolTip.Tip="Move document up in the list"
                                 Command="{Binding Editor.MoveDocumentUpCommand}" Padding="6,2"/>
-                        <Button Content="▼" ToolTip.Tip="Move down"
+                        <Button Content="▼" ToolTip.Tip="Move document down in the list"
                                 Command="{Binding Editor.MoveDocumentDownCommand}" Padding="6,2"/>
                     </StackPanel>
                     <ListBox ItemsSource="{Binding Editor.Documents}"
@@ -123,15 +137,15 @@
                 <DockPanel>
                     <TextBlock DockPanel.Dock="Top" Text="Layers" FontWeight="SemiBold" Margin="0,0,0,4"/>
                     <StackPanel DockPanel.Dock="Bottom" Orientation="Horizontal" Spacing="2" Margin="0,4,0,0">
-                        <Button Content="+" ToolTip.Tip="Add layer"
+                        <Button Content="+" ToolTip.Tip="Add a new empty layer"
                                 Command="{Binding Editor.AddLayerCommand}" Padding="6,2"/>
-                        <Button Content="−" ToolTip.Tip="Remove layer"
+                        <Button Content="−" ToolTip.Tip="Remove selected layer"
                                 Command="{Binding Editor.RemoveLayerCommand}" Padding="6,2"/>
-                        <Button Content="▲" ToolTip.Tip="Move up"
+                        <Button Content="▲" ToolTip.Tip="Move layer up (draw later, appears on top)"
                                 Command="{Binding Editor.MoveLayerUpCommand}" Padding="6,2"/>
-                        <Button Content="▼" ToolTip.Tip="Move down"
+                        <Button Content="▼" ToolTip.Tip="Move layer down (draw earlier, appears below)"
                                 Command="{Binding Editor.MoveLayerDownCommand}" Padding="6,2"/>
-                        <Button Content="⧉" ToolTip.Tip="Duplicate layer"
+                        <Button Content="⧉" ToolTip.Tip="Duplicate selected layer with all pixels"
                                 Command="{Binding Editor.DuplicateLayerCommand}" Padding="6,2"/>
                     </StackPanel>
                     <ListBox ItemsSource="{Binding Editor.Layers}"
diff --git a/Minint/Views/PatternDialog.axaml b/Minint/Views/PatternDialog.axaml
new file mode 100644
index 0000000..376e722
--- /dev/null
+++ b/Minint/Views/PatternDialog.axaml
@@ -0,0 +1,36 @@
+<Window xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        x:Class="Minint.Views.PatternDialog"
+        Title="Generate Pattern"
+        Width="360"
+        WindowStartupLocation="CenterOwner"
+        CanResize="False"
+        SizeToContent="Height">
+    <StackPanel Margin="16" Spacing="8">
+        <Grid ColumnDefinitions="100,*" RowDefinitions="Auto,Auto,Auto,Auto,Auto,Auto" RowSpacing="6" ColumnSpacing="8">
+            <TextBlock Grid.Row="0" Grid.Column="0" Text="Pattern:" VerticalAlignment="Center"/>
+            <ComboBox Grid.Row="0" Grid.Column="1" x:Name="PatternCombo" HorizontalAlignment="Stretch"/>
+
+            <TextBlock Grid.Row="1" Grid.Column="0" Text="Color 1:" VerticalAlignment="Center"/>
+            <ColorPicker Grid.Row="1" Grid.Column="1" x:Name="Color1Picker" IsAlphaVisible="False"/>
+
+            <TextBlock Grid.Row="2" Grid.Column="0" Text="Color 2:" VerticalAlignment="Center"/>
+            <ColorPicker Grid.Row="2" Grid.Column="1" x:Name="Color2Picker" IsAlphaVisible="False"/>
+
+            <TextBlock Grid.Row="3" Grid.Column="0" Text="Param 1:" VerticalAlignment="Center"/>
+            <NumericUpDown Grid.Row="3" Grid.Column="1" x:Name="Param1"
+                           Value="8" Minimum="1" Maximum="256" FormatString="0"
+                           ToolTip.Tip="Cell/stripe/ring size"/>
+
+            <TextBlock Grid.Row="4" Grid.Column="0" Text="Param 2:" VerticalAlignment="Center"/>
+            <NumericUpDown Grid.Row="4" Grid.Column="1" x:Name="Param2"
+                           Value="8" Minimum="1" Maximum="256" FormatString="0"
+                           ToolTip.Tip="Tile height (for Tile pattern)"/>
+        </Grid>
+
+        <StackPanel Orientation="Horizontal" HorizontalAlignment="Right" Spacing="8" Margin="0,12,0,0">
+            <Button Content="Generate" x:Name="OkButton" IsDefault="True" Padding="16,6"/>
+            <Button Content="Cancel" x:Name="CancelButton" IsCancel="True" Padding="16,6"/>
+        </StackPanel>
+    </StackPanel>
+</Window>
diff --git a/Minint/Views/PatternDialog.axaml.cs b/Minint/Views/PatternDialog.axaml.cs
new file mode 100644
index 0000000..b4a2d7a
--- /dev/null
+++ b/Minint/Views/PatternDialog.axaml.cs
@@ -0,0 +1,50 @@
+using System;
+using System.Linq;
+using Avalonia.Controls;
+using Avalonia.Interactivity;
+using Avalonia.Media;
+using Minint.Core.Models;
+using Minint.Core.Services;
+
+namespace Minint.Views;
+
+public partial class PatternDialog : Window
+{
+    public PatternType SelectedPattern =>
+        PatternCombo.SelectedItem is PatternType pt ? pt : PatternType.Checkerboard;
+
+    public RgbaColor PatternColor1
+    {
+        get
+        {
+            var c = Color1Picker.Color;
+            return new RgbaColor(c.R, c.G, c.B, c.A);
+        }
+    }
+
+    public RgbaColor PatternColor2
+    {
+        get
+        {
+            var c = Color2Picker.Color;
+            return new RgbaColor(c.R, c.G, c.B, c.A);
+        }
+    }
+
+    public int PatternParam1 => (int)(Param1.Value ?? 8);
+    public int PatternParam2 => (int)(Param2.Value ?? 8);
+
+    public PatternDialog()
+    {
+        InitializeComponent();
+
+        PatternCombo.ItemsSource = Enum.GetValues<PatternType>().ToList();
+        PatternCombo.SelectedIndex = 0;
+
+        Color1Picker.Color = Color.FromRgb(0, 0, 0);
+        Color2Picker.Color = Color.FromRgb(255, 255, 255);
+
+        OkButton.Click += (_, _) => Close(true);
+        CancelButton.Click += (_, _) => Close(false);
+    }
+}