DirectX Hardware Acceleration

  • 6 minutes to read

DirectX hardware acceleration allows your application to utilize a client machine's video card (integrated or dedicated) to render DevExpress controls. DirectX acceleration boosts applications' performance on 4K displays, where large data applications rendered with standard GDI+ can be unresponsive.

DirectX applications require the Windows 7 Platform Update (with DirectX 11), Windows 8 or newer. However, we do not recommend Windows 7 because the CreateSwapChainForHwnd method takes a DXGI_SWAP_CHAIN_DESC1 structure that has a field for Scaling. The DXGI_SCALING_NONE Scaling is not supported on Windows 7 with the platform update. As a result, the CreateSwapChainForHwnd method returns DXGI_ERROR_INVALID_CALL when called. This causes the DirectX-rendered Data Grid to jitter when users resize the form.

Enable DirectX Hardware Acceleration

You can enable DirectX rendering in the DevExpress Project Settings window.

To enable DirectX rendering, you can also call the static WindowsFormsSettings.ForceDirectXPaint method when the application starts.


using DevExpress.XtraEditors;

namespace WindowsFormsApplication1 {
    static class Program {
        /// <summary> 
        /// The application's main entry point. 
        /// </summary> 
        [STAThread]
        static void Main() {
            WindowsFormsSettings.ForceDirectXPaint();

            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);
            Application.Run(new Form1());
        }
    }
}

The ForceDirectXPaint method enables the DirectX hardware acceleration for the following controls:

To revert individual controls to the GDI+ engine, disable their UseDirectXPaint settings.


gridControl1.UseDirectXPaint = DevExpress.Utils.DefaultBoolean.False;

The following DevExpress controls' default UseDirectXPaint value is equal to DefaultBoolean.False. For these controls calling the static WindowsFormsSettings.ForceDirectXPaint method alone no effect. You should call the global static method and manually set their UseDirectXPaint properties to DefaultBoolean.True to enable the DirectX acceleration.


pictureEdit1.UseDirectXPaint = DevExpress.Utils.DefaultBoolean.True;

To use DirectX rendering in the PDF Viewer control, enable the PdfViewer.RenderPageContentWithDirectX property.

Hardware Recommendations

Displays

Applications benefit from DirectX acceleration on any display, but these advantages are more evident at higher resolutions (2K, WQHD, WQXGA, 4K, etc.).

Virtual Memory

Each control painted in DirectX mode requires its own DirectX device. You can set the optimal DirectX device number through the DevExpress.Utils.DirectXPaint.DirectXProvider.DeviceLimit property. If the current device number is equal to or higher than this DeviceLimit property value, new controls that need to be shown will still be painted with DirectX accelleration, however the application tries to release devices for currently hidden controls to keep the number of active devices below the threshold, which reduces the total virtual memory consumption.

API Limitations

DirectX hardware acceleration imposes the following restrictions on the API:

Unsupported API

Recommended Action

All API accessed through the e.Graphics property (for example, when handling custom draw events).

Utilize the GraphicsCache class API (available through the e.Cache property).

  • DirectX has no methods that accept image attributes. Instead, utilize the GraphicsCache methods that accept the ColorMatrix objects as parameters.
  • Methods that take Regions as parameters have no counterparts in GraphicsCache. Use methods that work with rectangles instead.
  • All GraphicsUnit enumeration values are treated as GraphicsUnit.Pixel.

Methods that use the Graphics class objects as parameters (for instance, the ControlPaint class methods).

No replacement, use similar methods instead.

The AppearanceObject.CalcDefaultTextSize(Graphics g) method overload

Replace with the AppearanceObject.CalcDefaultTextSize(GraphicsCache cache) overload

The following AppearanceObject.CalcTextSizeInt method overloads:

  • CalcTextSizeInt(Graphics g, StringFormat sf, string s, int width)
  • CalcTextSizeInt(Graphics g, string s, int width)

Replace with the following overloads:

  • CalcTextSizeInt(GraphicsCache cache, StringFormat sf, string s, int width)
  • CalcTextSizeInt(GraphicsCache cache, string s, int width)

The following AppearanceObject.CalcTextSize method overloads:

  • CalcTextSize(Graphics g, string s, int width)
  • CalcTextSize(Graphics g, StringFormat sf, string s, int width)
  • CalcTextSize(Graphics g, StringFormat sf, string s, int width, int height)
  • CalcTextSize(Graphics g, StringFormat sf, string s, int width, int height, out Boolean isCropped)

Replace with the following overloads:

  • CalcTextSize(GraphicsCache cache, string s, int width)
  • CalcTextSize(GraphicsCache cache, StringFormat sf, string s, int width)
  • CalcTextSize(GraphicsCache cache, StringFormat sf, string s, int width, int height)
  • CalcTextSize(GraphicsCache cache, StringFormat sf, string s, int width, int height, out Boolean isCropped)

The AppearanceObject.FontHeight property is obsolete

No replacement for this property. Revisit your code and use a different approach.

Custom fonts

Custom fonts that you use may be abscent on users' machines. For that reason, use system fonts only.

The InterpolationMode property in Graphics, GraphicsCache, and RepositoryItemPictureEdit classes supports only HighQualityBicubic and NearestNeighbor values.

CompositingMode, CompositingQuality, TextRenderingHint, SmoothingMode, and PixelOffsetMode properties in Graphics and GraphicsCache classes are ignored.

To detect all the unsupported APIs, call the static WindowsFormsSettings.ForcePaintApiDiagnostics method and set the security level as the first parameter:

  • Throw - unsupported APIs result in exceptions;
  • Trace - unsupported APIs display result in warnings, displayed in Visual Studio's "Output" window;
  • Disable - ignores unsupported API;
  • Default - acts as "Trace" if DirectX and\or Per-Monitor HiDPI support is enabled; otherwise, as "Disable".

//disable the API tracing
DevExpress.XtraEditors.WindowsFormsSettings.ForcePaintApiDiagnostics(DevExpress.Utils.Diagnostics.PaintApiDiagnosticsLevel.Disable);

The ForcePaintApiDiagnostics method's second parameter allows you to specify a custom behavior:


//The following sample implements the custom logging:
DevExpress.XtraEditors.WindowsFormsSettings.ForcePaintApiDiagnostics(PaintApiDiagnosticsLevel.Throw, (apiLevel, api) =>
    {
        System.Console.WriteLine(apiLevel.ToString() + ": " + api);
        //Suppress the Throw mode exceptions
        return PaintApiDiagnosticsLevel.Disable;
    });

Test Mode

DevExpress DirectX rendering is available only for graphics cards that support Direct3D Feature Levels equal to or higher than 11. To check your GPU's supported Feature Levels, run the "DirectX Diagnostic Tool": press "Win+R" to launch the "Run" dialog and type in the dxdiag command. Alternatively, in Visual Studio go to "Help | About Microsoft Visual Studio" and click the "DxDiag" button.

Direct3D Feature Levels

You can enable the Test Mode if your machine has Feature Levels of 10_2 or lower. This mode forces the application to use the DirectX rendering regardless of supported Feature Levels. Note that this mode is intended for debugging only.


#if DEBUG
    DevExpress.Utils.DirectXPaint.DirectXProvider.EnableTestMode()
#endif

You can also set the DirectXRenderLogMode property to RaiseDeviceCreationFailedEvent and handle the DeviceCreationFailed event to trace all cases when the application is unable to create a DirectX device.

DevExpress.Utils.DirectXPaint.DirectXProvider.DirectXRenderLogMode = DevExpress.Utils.DirectXPaint.DirectXRenderLogMode.RaiseDeviceCreationFailedEvent;
DevExpress.Utils.DirectXPaint.DirectXProvider.DeviceCreationFailed += DirectXProvider_DeviceCreationFailed;

private void DirectXProvider_DeviceCreationFailed(object sender, DevExpress.Utils.DirectXPaint.DeviceCreationFailedEventArgs e)
{
    //read the e.Log parameter
}