https://learn.microsoft.com/en-us/dotnet/api/system.windows.interop.d3dimage.adddirtyrect?view=netframework-4.8.1&viewFallbackFrom=windowsdesktop-10.0
D3DImage.AddDirtyRect(Int32Rect) Method (System.Windows.Interop) | Microsoft Learn
Specifies the area of the back buffer that changed.
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