3d - controlling FPS limit in OpenGL application

Question

I am trying to find a solid method for being able to set exactly how many FPS I want my OpenGL application to render on screen. I can do it to some extent by sleeping for 1000/fps milliseconds but that doesn't take into account the time needed to render. Which is the most consistent way to limit fps to desired amount?

Answer 1

you can sync to vblank by using wglSwapIntervalEXT in opengl. its not nice code, but it does work.

http://www.gamedev.net/topic/360862-wglswapintervalext/#entry3371062

bool WGLExtensionSupported(const char *extension_name) {
    PFNWGLGETEXTENSIONSSTRINGEXTPROC _wglGetExtensionsStringEXT = NULL;

    _wglGetExtensionsStringEXT = (PFNWGLGETEXTENSIONSSTRINGEXTPROC)wglGetProcAddress("wglGetExtensionsStringEXT");

    if (strstr(_wglGetExtensionsStringEXT(), extension_name) == NULL) {
        return false;
    }

    return true;
}

and

PFNWGLSWAPINTERVALEXTPROC       wglSwapIntervalEXT = NULL;
PFNWGLGETSWAPINTERVALEXTPROC    wglGetSwapIntervalEXT = NULL;

if (WGLExtensionSupported("WGL_EXT_swap_control"))
{
// Extension is supported, init pointers.
    wglSwapIntervalEXT = (PFNWGLSWAPINTERVALEXTPROC)wglGetProcAddress("wglSwapIntervalEXT");

// this is another function from WGL_EXT_swap_control extension
    wglGetSwapIntervalEXT = (PFNWGLGETSWAPINTERVALEXTPROC)wglGetProcAddress("wglGetSwapIntervalEXT");
}