How does one disable hardware acceleration in wpf?

Question

What is the procedure for disabling hardware acceleration in WPF? What is it exactly? Is it a Windows setting, a Visual Studio setting, or something you alter in the code of your WPF project? Will it affect only the program you're running or will it be system-wide?

Answer 1

You can disable it on a Window level starting from .Net 3.5 SP1.

public partial class MyWindow : Window
{
    public MyWindow()
        : base()
    {
        InitializeComponent();
    }

    protected override void OnSourceInitialized(EventArgs e)
    {
        var hwndSource = PresentationSource.FromVisual(this) as HwndSource;

        if (hwndSource != null)
            hwndSource.CompositionTarget.RenderMode = RenderMode.SoftwareOnly;

        base.OnSourceInitialized(e);
    }
}

or you can subscribe to SourceInitialized event of the window and do the same.

Alternatively you can set it on Process level:

RenderOptions.ProcessRenderMode = RenderMode.SoftwareOnly;

The precedence order for software rendering is:

1. DisableHWAcceleration registry key
2. ProcessRenderMode
3. RenderMode (per-target)

Answer 2

It is a machine-wide registry setting. See Graphics Rendering Registry Settings in the WPF docs for the registry key and other details relating to customizing WPF rendering.

The key listed is: HKEY_CURRENT_USER\SOFTWARE\Microsoft\Avalon.Graphics\DisableHWAcceleration

The MSDN document is "not available" for .NET 4.5, so this may be a depricated option that only works in 4.0 or below.