OpenGL and Mesa

glX Example

  #include <GL/glx.h>
  #include <GL/gl.h>
  #include <unistd.h>

  static int attributeList[] = { GLX_RGBA, None	};

  static Bool WaitForNotify(Display *d,	XEvent *e, char	*arg) {
      return (e->type == MapNotify) && (e->xmap.window == (Window)arg);
  }

  int main(int argc, char **argv) {
      Display *dpy;
      XVisualInfo *vi;
      Colormap cmap;
      XSetWindowAttributes swa;
      Window win;
      GLXContext cx;
      XEvent event;

      /* get a connection */
      dpy = XOpenDisplay(0);

      /* get an	appropriate visual */
      vi = glXChooseVisual(dpy,	DefaultScreen(dpy), attributeList);

      /* create	a GLX context */
      cx = glXCreateContext(dpy, vi, 0,	GL_TRUE);

      /* create	a color	map */
      cmap = XCreateColormap(dpy, RootWindow(dpy, vi->screen),
			     vi->visual, AllocNone);

      /* create	a window */
      swa.colormap = cmap;
      swa.border_pixel = 0;
      swa.event_mask = StructureNotifyMask;
      win = XCreateWindow(dpy, RootWindow(dpy, vi->screen), 0, 0, 100, 100,
			  0, vi->depth,	InputOutput, vi->visual,
			  CWBorderPixel|CWColormap|CWEventMask,	&swa);
      XMapWindow(dpy, win);
      XIfEvent(dpy, &event, WaitForNotify, (char*)win);

      /* connect the context to	the window */
      glXMakeCurrent(dpy, win, cx);

      /* clear the buffer */
      glClearColor(1,1,0,1);
      glClear(GL_COLOR_BUFFER_BIT);
      glFlush();

      /* wait a	while */
      sleep(10);
    }