Add FramedBeatmapClock

Expose `IsCoupled` in `FramedBeatmapClock` for now to provide editor compatibility

osu.Game/Beatmaps/FramedBeatmapClock.cs

@@ -0,0 +1,167 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System;
+using osu.Framework;
+using osu.Framework.Allocation;
+using osu.Framework.Audio.Track;
+using osu.Framework.Bindables;
+using osu.Framework.Graphics;
+using osu.Framework.Timing;
+using osu.Game.Configuration;
+using osu.Game.Database;
+using osu.Game.Screens.Play;
+
+namespace osu.Game.Beatmaps
+{
+    public class FramedBeatmapClock : Component, IFrameBasedClock, IAdjustableClock, ISourceChangeableClock
+    {
+        /// <summary>
+        /// The length of the underlying beatmap track. Will default to 60 seconds if unavailable.
+        /// </summary>
+        public double TrackLength => Track?.Length ?? 60000;
+
+        /// <summary>
+        /// The underlying beatmap track, if available.
+        /// </summary>
+        public Track? Track { get; private set; } // TODO: virtual rather than null?
+
+        private readonly OffsetCorrectionClock userGlobalOffsetClock;
+        private readonly OffsetCorrectionClock platformOffsetClock;
+        private readonly OffsetCorrectionClock finalOffsetClock;
+
+        private Bindable<double> userAudioOffset = null!;
+
+        private IDisposable? beatmapOffsetSubscription;
+
+        private readonly DecoupleableInterpolatingFramedClock decoupledClock;
+
+        private double totalAppliedOffset => userGlobalOffsetClock.RateAdjustedOffset + finalOffsetClock.RateAdjustedOffset + platformOffsetClock.RateAdjustedOffset;
+
+        [Resolved]
+        private OsuConfigManager config { get; set; } = null!;
+
+        [Resolved]
+        private RealmAccess realm { get; set; } = null!;
+
+        [Resolved]
+        private IBindable<WorkingBeatmap> beatmap { get; set; } = null!;
+
+        public bool IsCoupled
+        {
+            get => decoupledClock.IsCoupled;
+            set => decoupledClock.IsCoupled = value;
+        }
+
+        public FramedBeatmapClock(IClock? sourceClock = null)
+        {
+            // TODO: Unused for now?
+            var pauseFreqAdjust = new BindableDouble(1);
+
+            // A decoupled 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).
+            decoupledClock = new DecoupleableInterpolatingFramedClock { IsCoupled = true };
+            decoupledClock.ChangeSource(sourceClock);
+
+            // Audio timings in general with newer BASS versions don't match stable.
+            // This only seems to be required on windows. We need to eventually figure out why, with a bit of luck.
+            platformOffsetClock = new OffsetCorrectionClock(decoupledClock, pauseFreqAdjust) { Offset = RuntimeInfo.OS == RuntimeInfo.Platform.Windows ? 15 : 0 };
+
+            // User global offset (set in settings) should also be applied.
+            userGlobalOffsetClock = new OffsetCorrectionClock(platformOffsetClock, pauseFreqAdjust);
+
+            // User per-beatmap offset will be applied to this final clock.
+            finalOffsetClock = new OffsetCorrectionClock(userGlobalOffsetClock, pauseFreqAdjust);
+        }
+
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            userAudioOffset = config.GetBindable<double>(OsuSetting.AudioOffset);
+            userAudioOffset.BindValueChanged(offset => userGlobalOffsetClock.Offset = offset.NewValue, true);
+
+            beatmapOffsetSubscription = realm.SubscribeToPropertyChanged(
+                r => r.Find<BeatmapInfo>(beatmap.Value.BeatmapInfo.ID)?.UserSettings,
+                settings => settings.Offset,
+                val => finalOffsetClock.Offset = val);
+        }
+
+        protected override void Update()
+        {
+            base.Update();
+            finalOffsetClock.ProcessFrame();
+        }
+
+        protected override void Dispose(bool isDisposing)
+        {
+            base.Dispose(isDisposing);
+            beatmapOffsetSubscription?.Dispose();
+        }
+
+        #region Delegation of IAdjustableClock / ISourceChangeableClock to decoupled clock.
+
+        public void ChangeSource(IClock? source)
+        {
+            Track = source as Track;
+            decoupledClock.ChangeSource(source);
+        }
+
+        public IClock? Source => decoupledClock.Source;
+
+        public void Reset()
+        {
+            decoupledClock.Reset();
+            finalOffsetClock.ProcessFrame();
+        }
+
+        public void Start()
+        {
+            decoupledClock.Start();
+            finalOffsetClock.ProcessFrame();
+        }
+
+        public void Stop()
+        {
+            decoupledClock.Stop();
+            finalOffsetClock.ProcessFrame();
+        }
+
+        public bool Seek(double position)
+        {
+            bool success = decoupledClock.Seek(position - totalAppliedOffset);
+            finalOffsetClock.ProcessFrame();
+
+            return success;
+        }
+
+        public void ResetSpeedAdjustments() => decoupledClock.ResetSpeedAdjustments();
+
+        public double Rate
+        {
+            get => decoupledClock.Rate;
+            set => decoupledClock.Rate = value;
+        }
+
+        #endregion
+
+        #region Delegation of IFrameBasedClock to clock with all offsets applied
+
+        public double CurrentTime => finalOffsetClock.CurrentTime;
+
+        public bool IsRunning => finalOffsetClock.IsRunning;
+
+        public void ProcessFrame()
+        {
+            // Noop to ensure an external consumer doesn't process the internal clock an extra time.
+        }
+
+        public double ElapsedFrameTime => finalOffsetClock.ElapsedFrameTime;
+
+        public double FramesPerSecond => finalOffsetClock.FramesPerSecond;
+
+        public FrameTimeInfo TimeInfo => finalOffsetClock.TimeInfo;
+
+        #endregion
+    }
+}