Hi Guys,

I've again stuck with something I shouldn't and spent way too much time staring myself blind on something what I thought was simple. I got it to work some time ago, but lost my code for it. I even did a small app to demonstrate my issue.

I can't for the world make my windowed gl context start up with vsync enabled (The vsync state is decided by the driver) - once I enter glutGameMode and go back to windowed mode, vsync is now enabled. I have vsync set as the first thing after these two very important lines:

// Initialize glut
glutInit(&argc, argv);
// Initialize glee
GLeeInit();

Followed by:

glutInitWindowSize(gl_current_width, gl_current_height);
glut_window_hWnd = glutCreateWindow(window_title.c_str());
glutInitDisplayMode(GLUT_DEPTH | GLUT_RGB | GLUT_DOUBLE | GLUT_ALPHA | GLUT_STENCIL);

// Set swap interval
#ifdef _WIN32
 char *extensions = (char*)glGetString( GL_EXTENSIONS );
 if( strstr( extensions, "WGL_EXT_swap_control\0" ) == 0 )
 {
  return; // Error: WGL_EXT_swap_control extension not supported on your computer.");
 }
 else
 {
  wglSwapIntervalEXT = (GLEEPFNWGLSWAPINTERVALEXTPROC)wglGetProcAddress( "wglSwapIntervalEXT\0" );
  if( wglSwapIntervalEXT )
  {
   wglSwapIntervalEXT(1);
  }
 }
#endif
#ifdef __linux__
 glXSwapIntervalSGI(1);    // Nix
#endif

Have you tried enabling VSync after creating the window (on GLUT i think it was called glutCreateWindow(), not sure though), if it was not created before?

I've never actually tried to having VSync enabled at startup, i only had it possible to enable it by pressing a key.

Have you tried enabling VSync after creating the window (on GLUT i think it was called glutCreateWindow(), not sure though), if it was not created before?

I've never actually tried to having VSync enabled at startup, i only had it possible to enable it by pressing a key.

Whoops, Thanks! -looks like I accidentally erased that line when I first cleaned tabs and spaces in my post. (I fixed it now)

I also tested with setting the statement before glutCreateWindow(), that results in the GL error 1282 (Invalid operation) - I guess because the context is not ready at that point.

Now here's hoping someone tried starting up with vsync enabled...

EDIT: No, it was there all along, and in the wrong place too. I'm just blind...

I managed to fix it! You brought my attention to glutCreateWindow, and then I looked at the order of the other statements.

I also thought it was weird to set glutInitDisplayMode after glutCreateWindow. anyways, this is the order i ended up with, and it works! :)

glutInitDisplayMode(GLUT_DEPTH | GLUT_RGB | GLUT_DOUBLE | GLUT_ALPHA | GLUT_STENCIL);
glutInitWindowSize(gl_current_width, gl_current_height);
glut_window_hWnd = glutCreateWindow(window_title.c_str());
// Set swap interval...

(Also, it's incredible what difference a trip to the man pages can do. That and the religious error checking L. Spiro suggested is two of the best pieces of advice I realized/got for OpenGL)