VCL Controls: DirectX Hardware Acceleration

• Jun 28, 2023
• 3 minutes to read

The DirectX® hardware acceleration mode uses parallel calculations and utilizes a client machine’s integrated or discrete GPU to render DevExpress controls. Compared to a combination of GDI and GDI+, the DirectX® acceleration mode can increase the frame rate of graphics-rich applications with multiple animated visual elements on High-DPI (4K+) displays. The performance gain ranges from 1.5 to 3 times and depends on the number of simultaneously displayed visual elements, hardware configuration, operating system, and driver versions.

A control in DirectX® render mode creates a Direct3D device context and uses a Direct2D-based canvas instead of a combination of GDI and GDI+ API-based canvases to draw content and UI elements. This mode is the most beneficial on a client machine with a discrete graphics card, since calculation load shifts from CPU to GPU and bitmap storage relies on frame buffer objects in video memory instead of GDI-based images in system memory.

Supported DevExpress VCL Controls

The following graphics-rich controls support the DirectX® hardware acceleration mode:

VCL Chart Control

Allows you to visualize data as bar, area, line, pie, and doughnut series with multiple chart appearance customization options.

VCL Tile Controls

TdxTileControl and TdxTileBar controls allow you to create touch-friendly user interfaces inspired by Microsoft Windows® 8.

VCL Gallery Control

A gallery control is designed to display a set of items categorized into groups and arranged into rows and columns. Gallery controls include:

TdxGalleryControl

A gallery control.

TdxColorGallery

An unbound color gallery control.

TdxDBColorGallery

A data-aware color gallery control.

VCL Gantt Control

A project management tool that allows users to schedule activities related to project goals.

Enable DirectX® Render Mode

You can enable the DirectX® hardware acceleration mode application-wide or only for individual controls that support it.

Global Render Mode Setting

Assign rmDirectX to one of the following look-and-feel render mode properties to enable this mode application-wide:

• The RenderMode property available in the TcxLookAndFeelController and TdxSkinController components.

  Delphi

    dxSkinController1.RenderMode := rmDirectX;
  

  C++

    dxSkinController1->RenderMode = rmDirectX;
  

• The RenderMode property available in the root look & feel settings. Call the RootLookAndFeel global function to access this property.

  Delphi

    RootLookAndFeel.RenderMode := rmDirectX;
  

  C++

    RootLookAndFeel()->RenderMode = rmDirectX;
  

Individual Render Mode Settings

Assign rmDirectX to an individual control’s LookAndFeel.RenderMode property to enable the DirectX® render mode for the control. This setting has priority over global render mode settings.

Delphi

  dxChartControl1.RenderMode := rmGDIPlus;

C++

  dxChartControl1->RenderMode = rmGDIPlus;

Note

Render mode settings do not affect controls that support only the GDI render mode.

Fallback Render Mode

If a control cannot create a Direct3D device context, it uses GDI as the fallback render mode. This error can happen because of an unavailable DirectX11® API call due to an unsupported operating system version, a graphics card driver issue, etc.

Requirements and Limitations

• The DirectX® render mode is supported in Windows 7 Platform Update (with DirectX11®) and newer.

• The DirectX® render mode is unavailable if an application is in GDI Scaled mode because it draws DirectX-rendered controls unscaled at their original (unscaled) positions.

• All controls always rely on GDI and GDI+ at design time.

• A control’s Transparent property value has no effect in DirectX® render mode, since the control has an opaque Direct3D device context that overlaps any background elements.

• In DirectX® render mode, all GDI and GDI+ draw calls made through a control’s Canvas and ActiveCanvas properties have no effect.