Question

Setup

I’m using System.Windows.Forms.Form as window source. Constructor:

FormBorderStyle = FormBorderStyle.None;
WindowState = FormWindowState.Maximized;

---

Form-Load:

_Device = new Device(this, DeviceConfiguration.SelectConfiguration(Bits.Eight, Bits.Eight, Bits.Eight, Bits.Eight, Bits.Twentyfour, Bits.Eight, true, true), 1024, 768);
Debug.WriteLine(GL.GetString(GL.GL_EXTENSIONS));

base.OnLoad(e);

In the load method the device configuration is selected, which is actually working. Calls like GL.GetString(GL.GL_EXTENSIONS) are working. All gl-methods are loaded too so all used methods are supported.

---

Form-Shown:

Application.Initialize(this);
RenderSettings = new RenderSettings(this);

Debug.WriteLine("After setup render settings: " + GL.GetErrorDescription());

_Textures[0] = Resources.LoadTexture("Resources\\Buttons\\btn_big_bg_normal.dds");
_Textures[1] = Resources.LoadTexture("Resources\\Buttons\\btn_big_bg_normal.dds");


base.OnShown(e);

_IsShown = true;

The Application.Initialize(this) initializes the framework used ( written by me ) and is also initializing a default shader, which is working, and model which is not working.
This causes the rendering later to fail because the returning handle is invalid.

Framework

I’ve a own OpenGL-wrapper which has enums for all parameters to enable development without looking in the OpenGL-references many times. As example the method glGenBuffers:

[MethodGL]
public delegate void glGenBuffers(Int32 count, ArrayBufferHandle[] buffers);

The ArrayBufferHandle definition:

/// <summary>
/// Represents a handle to a buffer
/// </summary>
[StructLayout(LayoutKind.Explicit, Size = 4)]
[ComVisible(true)]
public struct ArrayBufferHandle
{
    [FieldOffset(0)]
    UInt32 Handle;
    /// <summary>
    /// Determines if the buffer is valid
    /// </summary>
    public Boolean IsValid { get { return Handle > 0; } }
    /// <summary>
    /// Retrieves the default array buffer
    /// <br>which is used to reset bindings</br>
    /// </summary>
    public static ArrayBufferHandle Default { get { return new ArrayBufferHandle(); } }
    /// <summary>
    /// Retrieves the string representation of the current object
    /// </summary>
    /// <returns>The current object represented as string</returns>
    public override String ToString()
    {
        return String.Format("[ArrayBufferHandle Handle:{0} Valid:{1}]", Handle, IsValid);
    }
}

Of course the shader creation is working and uses the types like the shown above.

Conclusion

I don’t think i’ve much more to say to the issues i’ve faced. glGenBuffers and glGenTextures returning zero and i don’t know why. The setup seems like others i’ve already used.

Of course the window is shown with a blue background when not rendering any models and i don’t have any errors when using glGetError.

Answer 1

First: Thanks to Mārtiņš Možeiko who led me into the right direction.

As it turns out the method void glGenBuffer(Int32 count, UInt32[] buffers) is working, but the method void glGenBuffers(Int32 count, ArrayBufferHandle[] buffers) isn’t. Both have a 4-byte / element array which is passed but .NET seems to handle them different. The solution has been simple:

void glGenBuffers(Int32 count, [Out]ArrayBufferHandle[] buffers)

Add a Out attribute to the array.