public override void Destroy()
{
if (fDisplay != IntPtr.Zero)
{
Glx.glXMakeCurrent(fDisplay, IntPtr.Zero, IntPtr.Zero);
if (fContext != IntPtr.Zero)
{
Glx.glXDestroyContext(fDisplay, fContext);
fContext = IntPtr.Zero;
}
if (fGlxPixmap != IntPtr.Zero)
{
Glx.glXDestroyGLXPixmap(fDisplay, fGlxPixmap);
fGlxPixmap = IntPtr.Zero;
}
if (fPixmap != IntPtr.Zero)
{
Xlib.XFreePixmap(fDisplay, fPixmap);
fPixmap = IntPtr.Zero;
}
fDisplay = IntPtr.Zero;
}
}
public static IntPtr[] ChooseFBConfig(IntPtr dpy, int screen, int[] attribList)
{
int nitems;
var fbcArrayPtr = glXChooseFBConfig(dpy, screen, attribList, out nitems);
var fbcArray = new IntPtr[nitems];
Marshal.Copy(fbcArrayPtr, fbcArray, 0, nitems);
Xlib.XFree(fbcArrayPtr);
return(fbcArray);
}
public static XVisualInfo GetVisualFromFBConfig(IntPtr dpy, IntPtr config)
{
var visualPtr = glXGetVisualFromFBConfig(dpy, config);
if (visualPtr == IntPtr.Zero)
{
throw new Exception("Failed to retrieve visual from framebuffer config.");
}
var visual = (XVisualInfo)Marshal.PtrToStructure(visualPtr, typeof(XVisualInfo));
Xlib.XFree(visualPtr);
return(visual);
}
public GlxContext()
{
fDisplay = Xlib.XOpenDisplay(null);
if (fDisplay == IntPtr.Zero)
{
Destroy();
throw new Exception("Failed to open X display.");
}
var visualAttribs = new [] {
Glx.GLX_X_RENDERABLE, Xlib.True,
Glx.GLX_DRAWABLE_TYPE, Glx.GLX_PIXMAP_BIT,
Glx.GLX_RENDER_TYPE, Glx.GLX_RGBA_BIT,
// Glx.GLX_DOUBLEBUFFER, Xlib.True,
Glx.GLX_RED_SIZE, 8,
Glx.GLX_GREEN_SIZE, 8,
Glx.GLX_BLUE_SIZE, 8,
Glx.GLX_ALPHA_SIZE, 8,
Glx.GLX_DEPTH_SIZE, 24,
Glx.GLX_STENCIL_SIZE, 8,
// Glx.GLX_SAMPLE_BUFFERS, 1,
// Glx.GLX_SAMPLES, 4,
Xlib.None
};
int glxMajor, glxMinor;
if (!Glx.glXQueryVersion(fDisplay, out glxMajor, out glxMinor) ||
(glxMajor < 1) ||
(glxMajor == 1 && glxMinor < 3))
{
Destroy();
throw new Exception("GLX version 1.3 or higher required.");
}
var fbc = Glx.ChooseFBConfig(fDisplay, Xlib.XDefaultScreen(fDisplay), visualAttribs);
if (fbc.Length == 0)
{
Destroy();
throw new Exception("Failed to retrieve a framebuffer config.");
}
var bestFBC = IntPtr.Zero;
var bestNumSamp = -1;
for (int i = 0; i < fbc.Length; i++)
{
int sampleBuf, samples;
Glx.glXGetFBConfigAttrib(fDisplay, fbc[i], Glx.GLX_SAMPLE_BUFFERS, out sampleBuf);
Glx.glXGetFBConfigAttrib(fDisplay, fbc[i], Glx.GLX_SAMPLES, out samples);
if (bestFBC == IntPtr.Zero || (sampleBuf > 0 && samples > bestNumSamp))
{
bestFBC = fbc[i];
bestNumSamp = samples;
}
}
var vi = Glx.GetVisualFromFBConfig(fDisplay, bestFBC);
fPixmap = Xlib.XCreatePixmap(fDisplay, Xlib.XRootWindow(fDisplay, vi.screen), 10, 10, (uint)vi.depth);
if (fPixmap == IntPtr.Zero)
{
Destroy();
throw new Exception("Failed to create pixmap.");
}
fGlxPixmap = Glx.glXCreateGLXPixmap(fDisplay, ref vi, fPixmap);
var glxExts = Glx.QueryExtensions(fDisplay, Xlib.XDefaultScreen(fDisplay));
if (Array.IndexOf(glxExts, "GLX_ARB_create_context") == -1 ||
Glx.glXCreateContextAttribsARB == null)
{
Console.WriteLine("OpenGL 3.0 doesn't seem to be available.");
fContext = Glx.glXCreateNewContext(fDisplay, bestFBC, Glx.GLX_RGBA_TYPE, IntPtr.Zero, Xlib.True);
}
else
{
// Let's just use OpenGL 3.0, but we could try find the highest
int major = 3, minor = 0;
var flags = new List <int> {
Glx.GLX_CONTEXT_MAJOR_VERSION_ARB, major,
Glx.GLX_CONTEXT_MINOR_VERSION_ARB, minor,
};
if (major > 2)
{
flags.AddRange(new[] {
Glx.GLX_CONTEXT_PROFILE_MASK_ARB, Glx.GLX_CONTEXT_COMPATIBILITY_PROFILE_BIT_ARB,
});
}
flags.Add(Xlib.None);
fContext = Glx.glXCreateContextAttribsARB(fDisplay, bestFBC, IntPtr.Zero, Xlib.True, flags.ToArray());
}
if (fContext == IntPtr.Zero)
{
Destroy();
throw new Exception("Failed to create an OpenGL context.");
}
if (!Glx.glXIsDirect(fDisplay, fContext))
{
Console.WriteLine("Obtained indirect GLX rendering context.");
}
}