Bail from score submission if audio playback rate is too far from reality

[peppy]

Closes #23149.

Values are ballparked (will trigger with ~1% rate difference over a 2.5 minute beatmap, ie. 300 * 5 total discrepancy). The count is added to avoid once-off discrepancies to not immediately cancel submission, ie. a large lag spike. This mostly matches how stable handles this.

Can be tested using:

diff --git a/osu.Game/Beatmaps/FramedBeatmapClock.cs b/osu.Game/Beatmaps/FramedBeatmapClock.cs
index 587e6bbeed..b1ed3235d6 100644
--- a/osu.Game/Beatmaps/FramedBeatmapClock.cs
+++ b/osu.Game/Beatmaps/FramedBeatmapClock.cs
@@ -61,9 +61,11 @@ public FramedBeatmapClock(bool applyOffsets, bool requireDecoupling, IClock? sou
 
             decoupledTrack = new DecouplingFramedClock(source) { AllowDecoupling = requireDecoupling };
 
+            var veryBadClock = new VeryBadClock(decoupledTrack);
+
             // An interpolating clock is used to ensure precise time values even when the host audio subsystem is not reporting
             // high precision times (on windows there's generally only 5-10ms reporting intervals, as an example).
-            var interpolatedTrack = new InterpolatingFramedClock(decoupledTrack);
+            var interpolatedTrack = new InterpolatingFramedClock(veryBadClock);
 
             if (applyOffsets)
             {
@@ -196,4 +198,29 @@ protected override void Dispose(bool isDisposing)
             beatmapOffsetSubscription?.Dispose();
         }
     }
+
+    public class VeryBadClock : IFrameBasedClock
+    {
+        private readonly IFrameBasedClock source;
+
+        public VeryBadClock(IFrameBasedClock source)
+        {
+            this.source = source;
+        }
+
+        public double CurrentTime => source.CurrentTime * 1.2;
+
+        public double Rate => source.Rate;
+
+        public bool IsRunning => source.IsRunning;
+
+        public void ProcessFrame()
+        {
+            source.ProcessFrame();
+        }
+
+        public double ElapsedFrameTime => source.ElapsedFrameTime;
+
+        public double FramesPerSecond => source.FramesPerSecond;
+    }
 }

Dunno how to make automated testing for this. Probably not required?

[Susko3]

Should probably be a localizable notification, as this is a user-facing string.

[bdach]

i argue this is not important for now

https://github.com/search?q=repo%3Appy%2Fosu%20LogLevel.Important&type=code

[peppy]

it's an edge case that only 1 in 10000000 will see, but sure, at some opint. the main goal is just to ensure some validity before score submit to stop bugged drivers from submitting.

[bdach]

How does this work? If elapsedValidationTime is null in a frame, doesn't this cause said frame to be double-counted?

I'd expect something closer to

                if (elapsedValidationTime == null)
                    elapsedValidationTime = elapsedGameplayClockTime;
                else
                    elapsedValidationTime += GameplayClock.Rate * Time.Elapsed;

[peppy]

Yeah, that looks better. Good catch.

[bdach]

One other way to test this is to use my broken ass wasapi device switching patch and rapidly switch output devices until it breaks (it'll usually speed up when broken). And this does catch it, for whatever that's worth.

So aside from the one doubt I have above, this appears to be doing the right thing as far as my somewhat limited testing shows.