WPF tocuh in Window with StylusPlugIn may throw InvalidOperationException

[lindexi]

• .NET Core Version: 6.0.121.56705
• Windows version: win10 21H2
• Does the bug reproduce also in WPF for .NET Framework 4.8?: No

Problem description:

After https://github.com/dotnet/wpf/pull/2891 the Stylus Input thread will call the GetAndCacheTransformToDeviceMatrix to get the Matrix to calculate.

https://github.com/dotnet/wpf/blob/ab8e3f026bc4319aae72e0b3b0383acbc500aeef/src/Microsoft.DotNet.Wpf/src/PresentationCore/System/Windows/Input/Stylus/Common/StylusLogic.cs#L417-L435

After we changed the moniter DPI and then we touch the application immediately, the GetAndCacheTransformToDeviceMatrix will call hwndSource.CompositionTarget.TransformToDevice and then throw the System.InvalidOperationException: The calling thread cannot access this object because a different thread owns it.

https://github.com/dotnet/wpf/blob/ab8e3f026bc4319aae72e0b3b0383acbc500aeef/src/Microsoft.DotNet.Wpf/src/PresentationCore/System/Windows/Input/Stylus/Common/StylusLogic.cs#L427

Because we can not find the new DpiScale in _transformToDeviceMatrices

Actual behavior:

Application: Application.exe
CoreCLR Version: 6.0.121.56705
.NET Version: 6.0.1
Description: The process was terminated due to an unhandled exception.
Exception Info: System.InvalidOperationException: The calling thread cannot access this object because a different thread owns it.
   at System.Windows.Threading.Dispatcher.ThrowVerifyAccess()
   at System.Windows.Threading.Dispatcher.VerifyAccess()
   at System.Windows.Threading.DispatcherObject.VerifyAccess()
   at System.Windows.Media.CompositionTarget.VerifyAPIReadOnly()
   at System.Windows.Interop.HwndTarget.get_TransformToDevice()
   at System.Windows.Input.StylusLogic.GetAndCacheTransformToDeviceMatrix(PresentationSource source)
   at System.Windows.Input.StylusWisp.WispLogic.GetTabletToViewTransform(PresentationSource source, TabletDevice tabletDevice)
   at System.Windows.Input.PenContexts.InvokeStylusPluginCollection(RawStylusInputReport inputReport)
   at System.Windows.Input.StylusWisp.WispLogic.InvokeStylusPluginCollection(RawStylusInputReport inputReport)
   at System.Windows.Input.StylusWisp.WispLogic.ProcessInputReport(RawStylusInputReport inputReport)
   at System.Windows.Input.StylusWisp.WispLogic.ProcessInput(RawStylusActions actions, PenContext penContext, Int32 tabletDeviceId, Int32 stylusDeviceId, Int32[] data, Int32 timestamp, PresentationSource inputSource)
   at System.Windows.Input.PenContexts.ProcessInput(RawStylusActions actions, PenContext penContext, Int32 tabletDeviceId, Int32 stylusPointerId, Int32[] data, Int32 timestamp)
   at System.Windows.Input.PenContexts.OnPenDown(PenContext penContext, Int32 tabletDeviceId, Int32 stylusPointerId, Int32[] data, Int32 timestamp)
   at System.Windows.Input.PenContext.FirePenDown(Int32 stylusPointerId, Int32[] data, Int32 timestamp)
   at System.Windows.Input.PenThreadWorker.FireEvent(PenContext penContext, Int32 evt, Int32 stylusPointerId, Int32 cPackets, Int32 cbPacket, IntPtr pPackets)
   at System.Windows.Input.PenThreadWorker.ThreadProc()
   at System.Threading.Thread.StartHelper.Callback(Object state)
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
--- End of stack trace from previous location ---
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.Thread.StartCallback()

Expected behavior:

Work well.

Minimal repro:

1. Create the application and attache the StylusPlugIn to main window
2. Run the application in the device with touch screen.
3. Touch the main window and then change the moniter DPI and then touch the application immediately

Repeat step 3 many times, and we will find the exception.

Reference: https://github.com/dotnet/wpf/issues/6415

cc @rladuca

[lindexi]

Why we cache the Matrix to _transformToDeviceMatrices ? Why not calculate the Matrix with hwndSource.CompositionTarget.CurrentDpiScale ?

The TransformToDevice property is calculate with CurrentDpiScale.

https://github.com/dotnet/wpf/blob/ab8e3f026bc4319aae72e0b3b0383acbc500aeef/src/Microsoft.DotNet.Wpf/src/PresentationCore/System/Windows/InterOp/HwndTarget.cs#L2334-L2343