Create C# Winforms with VC++ OpenGL Scene

[dinesh17]

Is it possible to render VC++ OpenGL output to a panel in Winforms window created with C# ? I’m aware of Tao framework and OpenTK but I don’t want to rely on third party support. There is an article here but this is merely only pixel reproduction and I think this method does not guarantee user interaction with OpenGL scene.

[Shinta]

Hiho,

I don’t know how your VC++ OpenGL output is realised, but I guess it will need a window (or device/rendering context) to work. So you’ll need a control in WinForms that acts as a canvas for OpenGL, any UserControl that set the class styles CS_VREDRAW, CS_HREDRAW and CS_OWNDC (and some WinForms control styles) should suffice. And since Control.Handle is set public, you can get the HWND handle (as IntPtr) there, and init your OpenGL output in VC++ with it.

public static class CS
{
    /// <summary>
    /// Redraws the entire window if a movement or size adjustment changes the height of the client area.
    /// </summary>
    public const int VREDRAW=0x00000001;

    /// <summary>
    /// Redraws the entire window if a movement or size adjustment changes the width of the client area.
    /// </summary>
    public const int HREDRAW=0x00000002;

    /// <summary>
    /// Allocates a unique device context for each window in the class.
    /// </summary>
    public const int OWNDC=0x00000020;

    // ... more
}

public partial class DummyOpenGLControl : UserControl
{
    /// <summary>
    /// Constructes a new instance of this class.
    /// </summary>
    public DummyOpenGLControl()
    {
        SetStyle(ControlStyles.AllPaintingInWmPaint|ControlStyles.Opaque|ControlStyles.ResizeRedraw|ControlStyles.UserPaint, true);
        SetStyle(ControlStyles.OptimizedDoubleBuffer, false);

        InitializeComponent();
    }

    /// <summary>
    /// Adds the class styles <see cref="CS.VREDRAW"/>, <see cref="CS.HREDRAW"/> and <see cref="CS.OWNDC"/> to support OpenGL rendering.
    /// </summary>
    protected override CreateParams CreateParams
    {
        get
        {
            CreateParams cp=base.CreateParams;
            cp.ClassStyle|=CS.VREDRAW|CS.HREDRAW|CS.OWNDC;
            // maybe cp.Style|=WS.CLIPCHILDREN|WS.CLIPSIBLINGS;
            return cp;
        }
    }

    // ... more
}

How you can connect your WinForms user interactions with your VC++ OpenGL output depends on the way it works, can’t help you there w/o more infos.