[Csgl-users] OpenGL & C# question

[Lloyd D. <ll...@ga...>]

Hello fellow C# users....

i am trying to improve my C# OpenGL library by enabling to create OpenGL 
context on any HDC... (printer, image, form, ....)

for this i create a new OpenGLContext class which have
a constructor like this:
-------------------------------------
[DllImport("csogl")]
IntPtr GLContextInitFromHDC(InpPtr p);

public OpenGLContext(Graphics g)
{
  ctxt = GLContextInitFromHDC(g.GetDc());	
}
---------------------------------

i use it like this
Bitmap b = new Bitmap(400, 400);
Graphics g = Graphics.FromImage(b);
OpenGLContext ogc = new OpenGLContext(g);

but when i try to call (win32) SetPixelFormat function this fail with
error 126 (ERROR_MOD_NOT_FOUND) , what this could be ?

here is my true interop code...
-- Warning: C - code --------------
typedef struct HG3D
{
	HWND  wnd;
	HDC   gdi;
	HGLRC glctxt;
}
G3D, * HG3D;
int GLContextInitFromHDC(HG3D ctxt, PIXELFORMATDESCRIPTOR * pix)
{
	int format = ChoosePixelFormat(ctxt->gdi, pix);

	if(!format) {
		SetLastError(ERROR_INVALID_INDEX);
		return 0;
	}
	if(ctxt->glctxt) {
		SetLastError(ERROR_ALREADY_INITIALIZED);
		return 0;
	}

// ->	// it failed HERE, with error 126: ERROR_MOD_NOT_FOUND
	if(!SetPixelFormat(ctxt->gdi, format, pix))
		return 0;
	if(!ctxt->glctxt)
		ctxt->glctxt = wglCreateContext(ctxt->gdi);
	return (int) ctxt->glctxt;
-----------------------------------