SDL2 FPS limit

[XITRIX]

/Is there any build in FPS limiter in SDL2?

I am running my app on different devices and I have very stable FPS count, so there is definitely some sort of FPS limit, but the problem that this limit is pretty random, on my MacBook it's 120fps, it's screen is also 120 hz so it's great. On my Nintendo Switch it's also 120, it's screen is only 60 hz, but I could limit it by my self, so it's not a problem, but on my iOS device it's 60 fps, while screen is 120 hz, so window looks really laggy on it. Moreover iOS app in MacOS mode works on 240 fps, while running it in iOS simulator shows ... maybe 1 fps ... (Update. Nevermind about simulator, it seems it has broken OpenGL)

I am using SDL_WINDOW_OPENGL flag to create a Window if it's matters.

[slouken]

Not specifically, there's code to simulate vsync if necessary, but there's no other specific FPS limiter in SDL.

[XITRIX]

I've finally managed this issue. In case someone will also find this problem here is my solution:

To allow iOS run app in 120 fps, you need to add <key>CADisableMinimumFrameDurationOnPhone</key><true/> into app's info.plist file

But doing ONLY that will not help, you also need to create CADisplayLink object and set it's preferredFrameRateRange to range from 80 to 120 fps. I've made it by modifying SDL's SDL_uikitappdelegate.m, in function didFinishLaunchingWithOptions I've added this right before SDL_SetMainReady();

if (@available(iOS 15.0, *)) {
        CADisplayLink* displayLink = [CADisplayLink displayLinkWithTarget:self selector:@selector(fpsUnlocker)];
        displayLink.preferredFrameRateRange = CAFrameRateRangeMake(80, 120, 120);
        [displayLink addToRunLoop:NSRunLoop.currentRunLoop forMode:NSDefaultRunLoopMode];
}

fpsUnlocker is just an empty function, you could declare it anywhere you'd like in that file

More information about this you could find in Apple's documentation here

[slouken]

Thanks for the info! This is fixed for SDL3.

[slouken]

.. and cherry-picked for the next SDL2 release. :)