Behaviour of Screen.currentResolution.refreshRateRatio

Target Platforms Mobile
,
1

Are the values in Screen.currentResolution.refreshRateRatio supposed to reflect changes made to
Application.targetFrameRate?

I have a Google Pixel 6a that I recently updated to Android 14. When I set the targetFrameRate, I get the following for the refreshRateRatio (rrr)

9443519--1325003--upload_2023-11-1_14-20-5.png
9443519--1325003--upload_2023-11-1_14-20-5.png1058×219 12.4 KB

The in game frame rate does change correctly, but these reported numbers seem wrong. I would swear the denominator used to change under Android 13 - but I might be dreaming…
Are the above results expected?

Jules

2

bump… does anyone know how targetFrameRate and refreshRateRatio are supposed to interact?

On a side note - I used to look forward to coming to these forums. The many diligent Unity and community folks who answered were extremely well informed and saved me a lot of development time. Recently - most of my questions go unanswered. Its rare I get a response from a unity rep. Makes me a bit sad.

3

I think that’s only true if setting the frame rate actually causes the Android device to change the screens refresh rate, which some do when you have optimized frame pacing on.

4

ok. thanks @AcidArrow . It makes a difference to how I determine which framerates to use for normal play, and for low-end or low battery devices. Doesn’t look like I can rely on the refreshRateRatio to tell me the current unity attempted rendering frame rate at all. I’m not sure what I can really use it for - other than determining the frame rate when the app started.

5

There’s no currently attempted framerate, it’s what you set it to. It’s 30 by default on mobile I think, but you should be setting it yourself.

Have an option like FPS Limit: 30 - 60 - Off. You should typically default to 60 and have it change to 30 if you think it’s a low powered device (how you determine that is tricky, maybe check device ram or something).

For “off” (which should be the maximum hz the device can do), do something like:

Resolution[] allResolutions = Screen.resolutions;
int maxRefresh = 30;
for (int i = 0; i < allResolutions.Length; i++) {
    maxRefresh = max(maxRefresh, allResolutions[i].refreshRate);
}
maxRefresh = clamp(maxRefresh, 30, 300);
Application.targetFrameRate = maxRefresh;
6

This seems to be broken on Android 14; we have run into the same problem and on Android 13 devices Screen.currentResolution.refreshRateRatio returns the correct refresh rate.

7

Can you elaborate? What seems broken?

8

I think the problem is that on Android 14 after you set the targetFrameRate, the refreshRateRatio.value does not change to match. Same question as in my OP.

I have a suspicion that the behaviour has changed between Android 13 and Android 14 - but I havent validated this.

9

@AcidArrow - I think you’re correct to mention OptimizedFramePacing above. This does seems to change the behaviour.