chore: sync alpha → alpha-backup (automated)

.github/workflows/build-testform.yml

@@ -86,7 +86,7 @@ jobs:
             ${{ runner.os }}-nuget-
 
       - name: Restore TestForm
-        run: dotnet restore "Source/Krypton Components/TestForm/TestForm.csproj" -p:Configuration=Release -p:TFMs=all
+        run: dotnet restore "Source/Krypton Components/TestForm/TestForm.csproj" -p:Configuration=Release -p:TFMs=all -p:ExcludeNet11=true
 
       - name: Validate TestForm linked resources
         shell: pwsh
@@ -137,7 +137,7 @@ jobs:
           }
 
       - name: Build TestForm
-        run: dotnet build "Source/Krypton Components/TestForm/TestForm.csproj" -p:Configuration=Release --no-restore -p:TFMs=all -m:1 -p:BuildInParallel=false
+        run: dotnet build "Source/Krypton Components/TestForm/TestForm.csproj" -p:Configuration=Release --no-restore -p:TFMs=all -p:ExcludeNet11=true -m:1 -p:BuildInParallel=false
 
       - name: Save NuGet cache
         if: success() && github.event_name != 'pull_request'

AGENTS.md

@@ -40,6 +40,7 @@
   - Direct VS2026 presets: `.\Scripts\Current\build-stable.cmd`, `.\Scripts\Current\build-canary.cmd`, `.\Scripts\Current\build-nightly.cmd`.
 - Outputs land under `Bin\<Configuration>\<TargetFramework>\` by default; with `UseArtifactsOutput=true`, outputs land under `artifacts\bin\<Configuration>\<TargetFramework>\`.
 - Target frameworks are selected by MSBuild properties. VS2019/full MSBuild builds only .NET Framework 4.x TFMs; VS2022/full MSBuild excludes `net10.0-windows` and `net11.0-windows`; VS2026/full MSBuild excludes `net11.0-windows` unless explicitly enabled; CI or SDK-based builds can include `net472`, `net48`, `net481`, `net8.0-windows`, `net9.0-windows`, `net10.0-windows`, and `net11.0-windows` when the required SDKs are installed.
+- New files must use only the current Standard Toolkit BSD header. Do not add the original ComponentFactory BSD header unless the file is derived from original ComponentFactory source.
 
 ## Coding Style & Naming Conventions
 

Documents/Changelog/Changelog.md

@@ -45,6 +45,7 @@
 
 ## 2026-11-xx - Build 2611 (V110 Nightly) - November 2026
 
+* Resolved [#3736](https://github.com/Krypton-Suite/Standard-Toolkit/issues/3736), Fixed high-dpi scaling causing magenta image borders
 * Implemented [#3718](https://github.com/Krypton-Suite/Standard-Toolkit/issues/3718), Use 'switch' expression
 * Resolved [#3720](https://github.com/Krypton-Suite/Standard-Toolkit/issues/3720), `KryptonTreeView` freezes blank after programmatic `SelectedNode = null` then re-select (drain leaked selection `BeginUpdate`/`EndUpdate` batches from #3282/#3498)
 * Resolved [#3719](https://github.com/Krypton-Suite/Standard-Toolkit/issues/3719), Information exposure through transmitted data

Source/Krypton Components/Krypton.Toolkit/Controls Toolkit/KryptonDataGridView.cs

@@ -183,6 +183,7 @@ private class ToolTipContent : IContentValues
     private KryptonVScrollBar? _roundingVScrollBar;
     private KryptonHScrollBar? _roundingHScrollBar;
     private bool _suppressRoundingScrollSync;
+    private bool _roundingResizeScrollSyncPending;
     private int _roundingScrollBarInteractionDepth;
     private System.Windows.Forms.Timer? _roundingScrollSyncTimer;
     private string _toolTipText;
@@ -1155,10 +1156,7 @@ protected override void OnScroll(ScrollEventArgs e)
     {
         base.OnScroll(e);
 
-        if (_roundingUsesDetachedScrollbars && !_suppressRoundingScrollSync && _roundingScrollBarInteractionDepth == 0)
-        {
-            SyncDetachedRoundingScrollbarsFromGrid(false);
-        }
+        SyncDetachedRoundingScrollbarsFromGridIfIdle(false);
 
         // #2681 - work-around
         // Headers not correctly repainted on horizontal mouse scroll
@@ -1333,7 +1331,7 @@ or KryptonDataGridViewDomainUpDownCell
         // the painting to fail.
         if ((_cellDown.X == -1) || (_cellDown.Y == -1))
         {
-            DoubleBuffered = false;
+            base.DoubleBuffered = false;
         }
 
         base.OnCellMouseDown(e);
@@ -1358,9 +1356,9 @@ protected override void OnCellMouseUp(DataGridViewCellMouseEventArgs e)
         _cellDown = _nullCell;
 
         // Put back double buffered if it was turned off in the OnCellMouseDown
-        if (!DoubleBuffered)
+        if (!base.DoubleBuffered)
         {
-            DoubleBuffered = true;
+            base.DoubleBuffered = true;
         }
 
         base.OnCellMouseUp(e);
@@ -1876,6 +1874,7 @@ protected override void OnResize(EventArgs e)
     {
         base.OnResize(e);
         UpdateRoundingAppearance();
+        QueueDetachedRoundingScrollbarsResizeSync();
     }
 
     /// <summary>
@@ -2799,6 +2798,7 @@ private void DisableDetachedRoundingScrollbars()
 
         bool wasUsingDetachedScrollbars = _roundingUsesDetachedScrollbars;
         _roundingScrollBarInteractionDepth = 0;
+        _roundingResizeScrollSyncPending = false;
         if (wasUsingDetachedScrollbars)
         {
             ShowNativeScrollbarsAfterRounding();
@@ -2981,24 +2981,18 @@ private void SyncDetachedRoundingScrollbarsFromGrid(bool layoutScrollbars)
             return;
         }
 
-        var hScrollInfo = new WIN32ScrollBars.ScrollInfo
-        {
-            cbSize = Marshal.SizeOf(typeof(WIN32ScrollBars.ScrollInfo)),
-            fMask = (int)PI.SIF_.ALL
-        };
         var vScrollInfo = new WIN32ScrollBars.ScrollInfo
         {
             cbSize = Marshal.SizeOf(typeof(WIN32ScrollBars.ScrollInfo)),
             fMask = (int)PI.SIF_.ALL
         };
 
-        bool hasHScroll = PI.GetScrollInfo(Handle, PI.SB_.HORZ, ref hScrollInfo);
         bool hasVScroll = PI.GetScrollInfo(Handle, PI.SB_.VERT, ref vScrollInfo);
 
         _suppressRoundingScrollSync = true;
         try
         {
-            UpdateDetachedHorizontalScrollBar(hasHScroll, hScrollInfo);
+            UpdateDetachedHorizontalScrollBar();
             UpdateDetachedVerticalScrollBar(hasVScroll, vScrollInfo);
         }
         finally
@@ -3009,41 +3003,66 @@ private void SyncDetachedRoundingScrollbarsFromGrid(bool layoutScrollbars)
         LayoutDetachedRoundingScrollbars(layoutScrollbars);
     }
 
-    private void UpdateDetachedHorizontalScrollBar(bool hasNativeScrollInfo, WIN32ScrollBars.ScrollInfo scrollInfo)
+    private void SyncDetachedRoundingScrollbarsFromGridIfIdle(bool layoutScrollbars)
+    {
+        if (_roundingUsesDetachedScrollbars && !_suppressRoundingScrollSync && _roundingScrollBarInteractionDepth == 0)
+        {
+            SyncDetachedRoundingScrollbarsFromGrid(layoutScrollbars);
+        }
+    }
+
+    private void QueueDetachedRoundingScrollbarsResizeSync()
+    {
+        if (!_roundingUsesDetachedScrollbars
+            || _roundingResizeScrollSyncPending
+            || !IsHandleCreated
+            || IsDisposed
+            || Disposing)
+        {
+            return;
+        }
+
+        _roundingResizeScrollSyncPending = true;
+        BeginInvoke((System.Windows.Forms.MethodInvoker)(() =>
+        {
+            _roundingResizeScrollSyncPending = false;
+
+            if (!_roundingUsesDetachedScrollbars
+                || !IsHandleCreated
+                || IsDisposed
+                || Disposing)
+            {
+                return;
+            }
+
+            HideNativeScrollbarsForRounding();
+            SyncDetachedRoundingScrollbarsFromGridIfIdle(true);
+        }));
+    }
+
+    private void UpdateDetachedHorizontalScrollBar()
     {
         if (_roundingHScrollBar == null || !WantsDetachedHorizontalScrollBar())
         {
-            if (_roundingHScrollBar != null)
+            if (_roundingHScrollBar != null && _roundingHScrollBar.Visible)
             {
                 _roundingHScrollBar.Visible = false;
             }
 
             return;
         }
 
-        SetDetachedHorizontalScrollBarBounds(false);
-
         int minimum;
         int maximum;
         int page;
         int position;
-        if (TryGetNativeDataGridScrollBarMetrics(true, out minimum, out maximum, out page, out position))
-        {
-            ApplyDetachedScrollBarMetrics(_roundingHScrollBar, minimum, maximum, page, position);
-            return;
-        }
-
-        if (hasNativeScrollInfo && TryGetNativeScrollMetrics(scrollInfo, out minimum, out maximum, out page, out position))
+        if (TryComputeHorizontalScrollMetrics(out minimum, out maximum, out page, out position))
         {
             ApplyDetachedScrollBarMetrics(_roundingHScrollBar, minimum, maximum, page, position);
             return;
         }
 
-        if (TryComputeHorizontalScrollMetrics(out minimum, out maximum, out page, out position))
-        {
-            ApplyDetachedScrollBarMetrics(_roundingHScrollBar, minimum, maximum, page, position);
-        }
-        else
+        if (_roundingHScrollBar.Visible)
         {
             _roundingHScrollBar.Visible = false;
         }
@@ -3053,16 +3072,14 @@ private void UpdateDetachedVerticalScrollBar(bool hasNativeScrollInfo, WIN32Scro
     {
         if (_roundingVScrollBar == null || !WantsDetachedVerticalScrollBar())
         {
-            if (_roundingVScrollBar != null)
+            if (_roundingVScrollBar != null && _roundingVScrollBar.Visible)
             {
                 _roundingVScrollBar.Visible = false;
             }
 
             return;
         }
 
-        SetDetachedVerticalScrollBarBounds(false);
-
         int minimum;
         int maximum;
         int page;
@@ -3085,7 +3102,10 @@ private void UpdateDetachedVerticalScrollBar(bool hasNativeScrollInfo, WIN32Scro
         }
         else
         {
-            _roundingVScrollBar.Visible = false;
+            if (_roundingVScrollBar.Visible)
+            {
+                _roundingVScrollBar.Visible = false;
+            }
         }
     }
 
@@ -3339,33 +3359,7 @@ private int GetVerticalScrollPositionInPixels()
 
     private int GetHorizontalScrollPositionInPixels()
     {
-        var hScrollInfo = new WIN32ScrollBars.ScrollInfo
-        {
-            cbSize = Marshal.SizeOf(typeof(WIN32ScrollBars.ScrollInfo)),
-            fMask = (int)PI.SIF_.POS
-        };
-
-        if (IsHandleCreated && PI.GetScrollInfo(Handle, PI.SB_.HORZ, ref hScrollInfo))
-        {
-            return hScrollInfo.nPos;
-        }
-
-        int position = 0;
-        int firstColumn = Math.Max(0, FirstDisplayedScrollingColumnIndex);
-        if (RowHeadersVisible)
-        {
-            position += RowHeadersWidth;
-        }
-
-        for (int i = 0; i < firstColumn && i < Columns.Count; i++)
-        {
-            if (Columns[i].Visible)
-            {
-                position += Columns[i].Width;
-            }
-        }
-
-        return position;
+        return HorizontalScrollingOffset;
     }
 
     private static int GetNativeScrollableMaximum(int minimum, int maximum, int page) =>
@@ -4093,6 +4087,14 @@ protected override void WndProc(ref Message m)
     }
     #endregion menus
 
+    /// <inheritdoc/>
+    protected override void OnColumnWidthChanged(DataGridViewColumnEventArgs e)
+    {
+        base.OnColumnWidthChanged(e);
+
+        SyncDetachedRoundingScrollbarsFromGridIfIdle(false);
+    }
+
     #region Column ButtonSpec wiring
     /// <summary>
     /// Wire column-specific ButtonSpec click events when a column is added.

Source/Krypton Components/Krypton.Toolkit/Rendering/RenderStandard.cs

@@ -5732,9 +5732,11 @@ private static void AllocateImageSpace([DisallowNull] StandardContentMemento mem
 					float ratio = Math.Min(displayRect.Width / (float)memento.Image.Width,
 						displayRect.Height / (float)memento.Image.Height);
 
+					bool avoidPurple = memento.ImageTransparentColor != GlobalStaticVariables.EMPTY_COLOR;
+
 					// Resize image to fit display area
 					memento.Image = CommonHelper.ScaleImageForSizedDisplay(memento.Image, memento.Image.Width * ratio,
-						memento.Image.Height * ratio, false);
+						memento.Image.Height * ratio, avoidPurple);
 				}
 
 				if (memento.Image != null)
@@ -12395,4 +12397,4 @@ internal void CalculateOverlayImagePosition()
 		}
 	}
 	#endregion
-}
+}

Source/Krypton Components/TestForm/TouchscreenHighDpiDemo.cs

@@ -25,6 +25,7 @@ public partial class TouchscreenHighDpiDemo : KryptonForm
 {
     private Timer _dpiMonitorTimer;
     private bool _updatingFromEvent;
+    private readonly Dictionary<Control, Rectangle> _baselineBounds = new();
 
     public TouchscreenHighDpiDemo()
     {
@@ -48,6 +49,8 @@ private void InitializeForm()
         // Setup demo controls
         SetupDemoControls();
 
+        grpSettings.Panel.AutoScroll = true;
+
         // Setup event handlers
         chkEnableTouchscreen.CheckedChanged += ChkEnableTouchscreen_CheckedChanged;
         trackScaleFactor.ValueChanged += TrackScaleFactor_ValueChanged;
@@ -376,13 +379,79 @@ private void UpdateUIFromSettings()
             trackFontScaleFactor.Enabled = fontScalingEnabled;
             lblFontScaleFactor.Enabled = touchscreenEnabled;
             lblFontScaleValue.Enabled = touchscreenEnabled;
+
+            ApplyScaledDemoLayout(settings);
         }
         finally
         {
             _updatingFromEvent = false;
         }
     }
 
+    private void ApplyScaledDemoLayout(TouchscreenSettingValues settings)
+    {
+        CaptureBaselineBounds(grpControls.Panel);
+        CaptureBaselineBounds(grpSettings.Panel);
+
+        float scaleFactor = 1f;
+        if (settings.TouchscreenModeEnabled)
+        {
+            scaleFactor = settings.ControlScaleFactor;
+            if (settings.FontScalingEnabled)
+            {
+                scaleFactor = Math.Max(scaleFactor, settings.FontScaleFactor);
+            }
+        }
+
+        scaleFactor = Math.Max(1f, scaleFactor);
+
+        grpControls.Panel.SuspendLayout();
+        grpSettings.Panel.SuspendLayout();
+
+        try
+        {
+            foreach (KeyValuePair<Control, Rectangle> entry in _baselineBounds)
+            {
+                Control control = entry.Key;
+                if (control.IsDisposed || control.Dock == DockStyle.Fill)
+                {
+                    continue;
+                }
+
+                Rectangle bounds = entry.Value;
+                control.Bounds = new Rectangle(
+                    ScaleLayoutValue(bounds.X, scaleFactor),
+                    ScaleLayoutValue(bounds.Y, scaleFactor),
+                    ScaleLayoutSize(bounds.Width, scaleFactor),
+                    ScaleLayoutSize(bounds.Height, scaleFactor));
+            }
+        }
+        finally
+        {
+            grpSettings.Panel.ResumeLayout(true);
+            grpControls.Panel.ResumeLayout(true);
+        }
+    }
+
+    private void CaptureBaselineBounds(Control parent)
+    {
+        foreach (Control child in parent.Controls)
+        {
+            if (child.Dock != DockStyle.Fill && !_baselineBounds.ContainsKey(child))
+            {
+                _baselineBounds.Add(child, child.Bounds);
+            }
+
+            CaptureBaselineBounds(child);
+        }
+    }
+
+    private static int ScaleLayoutValue(int value, float scaleFactor) =>
+        Math.Max(0, (int)Math.Round(value * scaleFactor));
+
+    private static int ScaleLayoutSize(int value, float scaleFactor) =>
+        Math.Max(1, (int)Math.Round(value * scaleFactor));
+
     private void UpdateStatus()
     {
         var settings = KryptonManager.TouchscreenSettingValues;