When glfwSwapInterval is disabled (0), then the program will run as fast as it possibly can – once the program has drawn a frame, it moves right onto to the next frame without worrying about weather drawing at this point in the display’s refresh might cause page-tearing or anything.

These are your two built-in options.

The third option, which we need to implement ourselves, can be to lock our program to a specified refresh rate by working out how many milliseconds we want each frame to take (i.e. 60fps = 1000 / 60 = 16.6667ms), and then in our main loop we:

1. Get the current system time (frameStart time)
2. Do stuff and draw the frame,
3. Get the current system time (frameEnd time),
4. Calculate the frameDraw time (which is frameStart – frameEnd),
5. If the frameDraw time is > 16.667ms draw the next frame, otherwise, if the frameDraw time is < 16.667ms, sleep for (16.667 - frameDraw time)ms

To do this, you can use code like this:

// Frame limiting vars
int    desiredFPS = 60;
double msPerFrame = 1000 / desiredFPS;
double frameStartTime, frameEndTime, frameDrawTime;
 
 
// ***** Everything below this line goes inside the main loop *****
frameStartTime = glfwGetTime();
 
// Do any calculations and draw the frame here
 
// Lock to ~60fps
frameEndTime = glfwGetTime();
frameDrawTime = frameEndTime - frameStartTime;
if (frameDrawTime < msPerFrame)
{
	glfwSleep(msPerFrame - frameDrawTime);
}

Hope this helps.

I found Glut really flexible on this as its underlying system won’t strict automatically to some setting of fps.

If you really want the C::B project let me know and I’ll upload it.

// Specify the function which should execute when a key is pressed or released
glfwSetKeyCallback(handleKeypress);
 
// Specify the function which should execute when the mouse is moved
glfwSetMousePosCallback(handleMouseMove);

The mouse cursor is supposed to be in the dead-centre of the screen and invisible, because the way we handle mouse movement is to calc how far from the centre of the screen the mouse has moved per frame (i.e. + or – horizontally (x-axis) and + or – vertically (y-axis) ), and then modify the ModelView matrix accordingly so you actually “look” in different directions. The mouse cursor then gets set back to the dead-centre of the window after each frame where we detect some cursor movement.

I’ve dug out some example code from when I was learning keyboard and mouse handlers for you. Once you can get those to work, you should be fine for the FPS controls:
GLFWKeyboardHandlerTest.zip
GLFWMouseHandlerTest.zip

Hope this helps.

Update: I should add that as far as I’m concerned these mouse and keyboard handlers work perfectly. I just don’t know if they’ll work for you. They should, but who knows… Could be something specific to your setup causing issues.

Thanks for the code. I used your keyboard and mouse input code in my program but the mouse is stationary in the middle of the screen and won’t move way up or down. Nothing happens when I press the keyboard too. Any pointers as to what I might be doing wrong and how I can tweak your code to work for me?