Merge remote-tracking branch 'master/master' into evaluators

osu.Android.props

@@ -52,7 +52,7 @@
   </ItemGroup>
   <ItemGroup>
     <PackageReference Include="ppy.osu.Game.Resources" Version="2022.527.0" />
-    <PackageReference Include="ppy.osu.Framework.Android" Version="2022.605.0" />
+    <PackageReference Include="ppy.osu.Framework.Android" Version="2022.611.0" />
   </ItemGroup>
   <ItemGroup Label="Transitive Dependencies">
     <!-- Realm needs to be directly referenced in all Xamarin projects, as it will not pull in its transitive dependencies otherwise. -->

osu.Desktop/Program.cs

@@ -113,6 +113,9 @@ namespace osu.Desktop
             {
                 tools.CreateShortcutForThisExe();
                 tools.CreateUninstallerRegistryEntry();
+            }, onAppUpdate: (version, tools) =>
+            {
+                tools.CreateUninstallerRegistryEntry();
             }, onAppUninstall: (version, tools) =>
             {
                 tools.RemoveShortcutForThisExe();

osu.Game.Rulesets.Catch/Difficulty/Preprocessing/CatchDifficultyHitObject.cs

@@ -25,8 +25,8 @@ namespace osu.Game.Rulesets.Catch.Difficulty.Preprocessing
         /// </summary>
         public readonly double StrainTime;
 
-        public CatchDifficultyHitObject(HitObject hitObject, HitObject lastObject, double clockRate, float halfCatcherWidth, List<DifficultyHitObject> objects, int position)
+        public CatchDifficultyHitObject(HitObject hitObject, HitObject lastObject, double clockRate, float halfCatcherWidth, List<DifficultyHitObject> objects, int index)
-            : base(hitObject, lastObject, clockRate, objects, position)
+            : base(hitObject, lastObject, clockRate, objects, index)
         {
             // We will scale everything by this factor, so we can assume a uniform CircleSize among beatmaps.
             float scalingFactor = normalized_hitobject_radius / halfCatcherWidth;

osu.Game.Rulesets.Mania/Difficulty/Preprocessing/ManiaDifficultyHitObject.cs

@@ -12,8 +12,8 @@ namespace osu.Game.Rulesets.Mania.Difficulty.Preprocessing
     {
         public new ManiaHitObject BaseObject => (ManiaHitObject)base.BaseObject;
 
-        public ManiaDifficultyHitObject(HitObject hitObject, HitObject lastObject, double clockRate, List<DifficultyHitObject> objects, int position)
+        public ManiaDifficultyHitObject(HitObject hitObject, HitObject lastObject, double clockRate, List<DifficultyHitObject> objects, int index)
-            : base(hitObject, lastObject, clockRate, objects, position)
+            : base(hitObject, lastObject, clockRate, objects, index)
         {
         }
     }

osu.Game.Rulesets.Osu/Difficulty/Evaluators/AimEvaluator.cs

@@ -26,7 +26,7 @@ namespace osu.Game.Rulesets.Osu.Difficulty.Evaluators
         /// </summary>
         public static double EvaluateDifficultyOf(DifficultyHitObject current, bool withSliders)
         {
-            if (current.BaseObject is Spinner || current.Position <= 1 || current.Previous(0).BaseObject is Spinner)
+            if (current.BaseObject is Spinner || current.Index <= 1 || current.Previous(0).BaseObject is Spinner)
                 return 0;
 
             var osuCurrObj = (OsuDifficultyHitObject)current;

osu.Game.Rulesets.Osu/Difficulty/Evaluators/FlashlightEvaluator.cs

@@ -38,7 +38,7 @@ namespace osu.Game.Rulesets.Osu.Difficulty.Evaluators
             OsuDifficultyHitObject lastObj = osuCurrent;
 
             // This is iterating backwards in time from the current object.
-            for (int i = 0; i < Math.Min(current.Position, 10); i++)
+            for (int i = 0; i < Math.Min(current.Index, 10); i++)
             {
                 var currentObj = (OsuDifficultyHitObject)current.Previous(i);
                 var currentHitObject = (OsuHitObject)(currentObj.BaseObject);

osu.Game.Rulesets.Osu/Difficulty/Evaluators/RhythmEvaluator.cs

@@ -29,7 +29,7 @@ namespace osu.Game.Rulesets.Osu.Difficulty.Evaluators
 
             bool firstDeltaSwitch = false;
 
-            int historicalNoteCount = Math.Min(current.Position, 32);
+            int historicalNoteCount = Math.Min(current.Index, 32);
 
             int rhythmStart = 0;
 

osu.Game.Rulesets.Osu/Difficulty/Evaluators/SpeedEvaluator.cs

@@ -30,7 +30,7 @@ namespace osu.Game.Rulesets.Osu.Difficulty.Evaluators
 
             // derive strainTime for calculation
             var osuCurrObj = (OsuDifficultyHitObject)current;
-            var osuPrevObj = current.Position > 0 ? (OsuDifficultyHitObject)current.Previous(0) : null;
+            var osuPrevObj = current.Index > 0 ? (OsuDifficultyHitObject)current.Previous(0) : null;
 
             double strainTime = osuCurrObj.StrainTime;
             double greatWindowFull = greatWindow * 2;

osu.Game.Rulesets.Osu/Difficulty/OsuDifficultyCalculator.cs

@@ -92,7 +92,10 @@ namespace osu.Game.Rulesets.Osu.Difficulty
             // The first jump is formed by the first two hitobjects of the map.
             // If the map has less than two OsuHitObjects, the enumerator will not return anything.
             for (int i = 1; i < beatmap.HitObjects.Count; i++)
-                objects.Add(new OsuDifficultyHitObject(beatmap.HitObjects[i], beatmap.HitObjects[i - 1], clockRate, objects, objects.Count));
+            {
+                var lastLast = i > 1 ? beatmap.HitObjects[i - 2] : null;
+                objects.Add(new OsuDifficultyHitObject(beatmap.HitObjects[i], beatmap.HitObjects[i - 1], lastLast, clockRate, objects, objects.Count));
+            }
 
             return objects;
         }

osu.Game.Rulesets.Osu/Difficulty/Preprocessing/OsuDifficultyHitObject.cs

@@ -75,10 +75,10 @@ namespace osu.Game.Rulesets.Osu.Difficulty.Preprocessing
         private readonly OsuHitObject lastLastObject;
         private readonly OsuHitObject lastObject;
 
-        public OsuDifficultyHitObject(HitObject hitObject, HitObject lastObject, double clockRate, List<DifficultyHitObject> objects, int position)
+        public OsuDifficultyHitObject(HitObject hitObject, HitObject lastObject, HitObject lastLastObject, double clockRate, List<DifficultyHitObject> objects, int index)
-            : base(hitObject, lastObject, clockRate, objects, position)
+            : base(hitObject, lastObject, clockRate, objects, index)
         {
-            lastLastObject = (OsuHitObject)Previous(1)?.BaseObject;
+            this.lastLastObject = (OsuHitObject)lastLastObject;
             this.lastObject = (OsuHitObject)lastObject;
 
             // Capped to 25ms to prevent difficulty calculation breaking from simultaneous objects.

osu.Game.Rulesets.Taiko/Difficulty/Preprocessing/TaikoDifficultyHitObject.cs

@@ -39,9 +39,9 @@ namespace osu.Game.Rulesets.Taiko.Difficulty.Preprocessing
         /// <param name="lastLastObject">The gameplay <see cref="HitObject"/> preceding <paramref name="lastObject"/>.</param>
         /// <param name="clockRate">The rate of the gameplay clock. Modified by speed-changing mods.</param>
         /// <param name="objects">The list of <see cref="DifficultyHitObject"/>s in the current beatmap.</param>
-        /// /// <param name="position">The position of this <see cref="DifficultyHitObject"/> in the <paramref name="objects"/> list.</param>
+        /// /// <param name="index">The position of this <see cref="DifficultyHitObject"/> in the <paramref name="objects"/> list.</param>
-        public TaikoDifficultyHitObject(HitObject hitObject, HitObject lastObject, HitObject lastLastObject, double clockRate, List<DifficultyHitObject> objects, int position)
+        public TaikoDifficultyHitObject(HitObject hitObject, HitObject lastObject, HitObject lastLastObject, double clockRate, List<DifficultyHitObject> objects, int index)
-            : base(hitObject, lastObject, clockRate, objects, position)
+            : base(hitObject, lastObject, clockRate, objects, index)
         {
             var currentHit = hitObject as Hit;
 

osu.Game.Rulesets.Taiko/Difficulty/Skills/Rhythm.cs

@@ -106,7 +106,7 @@ namespace osu.Game.Rulesets.Taiko.Difficulty.Skills
                     if (!samePattern(start, mostRecentPatternsToCompare))
                         continue;
 
-                    int notesSince = hitObject.Position - rhythmHistory[start].Position;
+                    int notesSince = hitObject.Index - rhythmHistory[start].Index;
                     penalty *= repetitionPenalty(notesSince);
                     break;
                 }

osu.Game.Tests/Collections/IO/ImportCollectionsTest.cs

@@ -49,11 +49,16 @@ namespace osu.Game.Tests.Collections.IO
 
                     Assert.That(osu.CollectionManager.Collections.Count, Is.EqualTo(2));
 
+                    // Even with no beatmaps imported, collections are tracking the hashes and will continue to.
+                    // In the future this whole mechanism will be replaced with having the collections in realm,
+                    // but until that happens it makes rough sense that we want to track not-yet-imported beatmaps
+                    // and have them associate with collections if/when they become available.
+
                     Assert.That(osu.CollectionManager.Collections[0].Name.Value, Is.EqualTo("First"));
-                    Assert.That(osu.CollectionManager.Collections[0].Beatmaps.Count, Is.Zero);
+                    Assert.That(osu.CollectionManager.Collections[0].BeatmapHashes.Count, Is.EqualTo(1));
 
                     Assert.That(osu.CollectionManager.Collections[1].Name.Value, Is.EqualTo("Second"));
-                    Assert.That(osu.CollectionManager.Collections[1].Beatmaps.Count, Is.Zero);
+                    Assert.That(osu.CollectionManager.Collections[1].BeatmapHashes.Count, Is.EqualTo(12));
                 }
                 finally
                 {
@@ -76,10 +81,10 @@ namespace osu.Game.Tests.Collections.IO
                     Assert.That(osu.CollectionManager.Collections.Count, Is.EqualTo(2));
 
                     Assert.That(osu.CollectionManager.Collections[0].Name.Value, Is.EqualTo("First"));
-                    Assert.That(osu.CollectionManager.Collections[0].Beatmaps.Count, Is.EqualTo(1));
+                    Assert.That(osu.CollectionManager.Collections[0].BeatmapHashes.Count, Is.EqualTo(1));
 
                     Assert.That(osu.CollectionManager.Collections[1].Name.Value, Is.EqualTo("Second"));
-                    Assert.That(osu.CollectionManager.Collections[1].Beatmaps.Count, Is.EqualTo(12));
+                    Assert.That(osu.CollectionManager.Collections[1].BeatmapHashes.Count, Is.EqualTo(12));
                 }
                 finally
                 {
@@ -142,8 +147,8 @@ namespace osu.Game.Tests.Collections.IO
                     await importCollectionsFromStream(osu, TestResources.OpenResource("Collections/collections.db"));
 
                     // Move first beatmap from second collection into the first.
-                    osu.CollectionManager.Collections[0].Beatmaps.Add(osu.CollectionManager.Collections[1].Beatmaps[0]);
+                    osu.CollectionManager.Collections[0].BeatmapHashes.Add(osu.CollectionManager.Collections[1].BeatmapHashes[0]);
-                    osu.CollectionManager.Collections[1].Beatmaps.RemoveAt(0);
+                    osu.CollectionManager.Collections[1].BeatmapHashes.RemoveAt(0);
 
                     // Rename the second collecction.
                     osu.CollectionManager.Collections[1].Name.Value = "Another";
@@ -164,10 +169,10 @@ namespace osu.Game.Tests.Collections.IO
                     Assert.That(osu.CollectionManager.Collections.Count, Is.EqualTo(2));
 
                     Assert.That(osu.CollectionManager.Collections[0].Name.Value, Is.EqualTo("First"));
-                    Assert.That(osu.CollectionManager.Collections[0].Beatmaps.Count, Is.EqualTo(2));
+                    Assert.That(osu.CollectionManager.Collections[0].BeatmapHashes.Count, Is.EqualTo(2));
 
                     Assert.That(osu.CollectionManager.Collections[1].Name.Value, Is.EqualTo("Another"));
-                    Assert.That(osu.CollectionManager.Collections[1].Beatmaps.Count, Is.EqualTo(11));
+                    Assert.That(osu.CollectionManager.Collections[1].BeatmapHashes.Count, Is.EqualTo(11));
                 }
                 finally
                 {

osu.Game.Tests/Visual/Collections/TestSceneManageCollectionsDialog.cs

@@ -152,7 +152,7 @@ namespace osu.Game.Tests.Visual.Collections
             AddStep("add two collections with same name", () => manager.Collections.AddRange(new[]
             {
                 new BeatmapCollection { Name = { Value = "1" } },
-                new BeatmapCollection { Name = { Value = "1" }, Beatmaps = { beatmapManager.GetAllUsableBeatmapSets().First().Beatmaps[0] } },
+                new BeatmapCollection { Name = { Value = "1" }, BeatmapHashes = { beatmapManager.GetAllUsableBeatmapSets().First().Beatmaps[0].MD5Hash } },
             }));
         }
 
@@ -162,7 +162,7 @@ namespace osu.Game.Tests.Visual.Collections
             AddStep("add two collections", () => manager.Collections.AddRange(new[]
             {
                 new BeatmapCollection { Name = { Value = "1" } },
-                new BeatmapCollection { Name = { Value = "2" }, Beatmaps = { beatmapManager.GetAllUsableBeatmapSets().First().Beatmaps[0] } },
+                new BeatmapCollection { Name = { Value = "2" }, BeatmapHashes = { beatmapManager.GetAllUsableBeatmapSets().First().Beatmaps[0].MD5Hash } },
             }));
 
             assertCollectionCount(2);
@@ -198,7 +198,7 @@ namespace osu.Game.Tests.Visual.Collections
         {
             AddStep("add two collections", () => manager.Collections.AddRange(new[]
             {
-                new BeatmapCollection { Name = { Value = "1" }, Beatmaps = { beatmapManager.GetAllUsableBeatmapSets().First().Beatmaps[0] } },
+                new BeatmapCollection { Name = { Value = "1" }, BeatmapHashes = { beatmapManager.GetAllUsableBeatmapSets().First().Beatmaps[0].MD5Hash } },
             }));
 
             assertCollectionCount(1);

osu.Game.Tests/Visual/Settings/TestSceneLatencyCertifierScreen.cs

@@ -0,0 +1,96 @@
+// 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.
+
+#nullable enable
+
+using System.Linq;
+using NUnit.Framework;
+using osu.Framework.Testing;
+using osu.Game.Graphics.UserInterface;
+using osu.Game.Screens.Utility;
+using osuTK.Input;
+
+namespace osu.Game.Tests.Visual.Settings
+{
+    public class TestSceneLatencyCertifierScreen : ScreenTestScene
+    {
+        private LatencyCertifierScreen latencyCertifier = null!;
+
+        public override void SetUpSteps()
+        {
+            base.SetUpSteps();
+
+            AddStep("Load screen", () => LoadScreen(latencyCertifier = new LatencyCertifierScreen()));
+            AddUntilStep("wait for load", () => latencyCertifier.IsLoaded);
+        }
+
+        [Test]
+        public void TestSimple()
+        {
+            AddStep("set visual mode to simple", () => latencyCertifier.VisualMode.Value = LatencyVisualMode.Simple);
+        }
+
+        [Test]
+        public void TestCircleGameplay()
+        {
+            AddStep("set visual mode to circles", () => latencyCertifier.VisualMode.Value = LatencyVisualMode.CircleGameplay);
+        }
+
+        [Test]
+        public void TestScrollingGameplay()
+        {
+            AddStep("set visual mode to scrolling", () => latencyCertifier.VisualMode.Value = LatencyVisualMode.ScrollingGameplay);
+        }
+
+        [Test]
+        public void TestCycleVisualModes()
+        {
+            AddRepeatStep("cycle mode", () => InputManager.Key(Key.Space), 6);
+        }
+
+        [Test]
+        public void TestCertification()
+        {
+            checkDifficulty(1);
+            clickUntilResults(true);
+            continueFromResults();
+            checkDifficulty(2);
+
+            clickUntilResults(false);
+            continueFromResults();
+            checkDifficulty(1);
+
+            clickUntilResults(true);
+            AddAssert("check at results", () => !latencyCertifier.ChildrenOfType<LatencyArea>().Any());
+            checkDifficulty(1);
+        }
+
+        private void continueFromResults()
+        {
+            AddAssert("check at results", () => !latencyCertifier.ChildrenOfType<LatencyArea>().Any());
+            AddStep("hit enter to continue", () => InputManager.Key(Key.Enter));
+        }
+
+        private void checkDifficulty(int difficulty)
+        {
+            AddAssert($"difficulty is {difficulty}", () => latencyCertifier.DifficultyLevel == difficulty);
+        }
+
+        private void clickUntilResults(bool clickCorrect)
+        {
+            AddUntilStep("click correct button until results", () =>
+            {
+                var latencyArea = latencyCertifier
+                                  .ChildrenOfType<LatencyArea>()
+                                  .SingleOrDefault(a => clickCorrect ? a.TargetFrameRate == null : a.TargetFrameRate != null);
+
+                // reached results
+                if (latencyArea == null)
+                    return true;
+
+                latencyArea.ChildrenOfType<OsuButton>().Single().TriggerClick();
+                return false;
+            });
+        }
+    }
+}

osu.Game.Tests/Visual/SongSelect/TestSceneFilterControl.cs

@@ -151,10 +151,10 @@ namespace osu.Game.Tests.Visual.SongSelect
             AddStep("add collection", () => collectionManager.Collections.Add(new BeatmapCollection { Name = { Value = "1" } }));
             AddAssert("button is plus", () => getAddOrRemoveButton(1).Icon.Equals(FontAwesome.Solid.PlusSquare));
 
-            AddStep("add beatmap to collection", () => collectionManager.Collections[0].Beatmaps.Add(Beatmap.Value.BeatmapInfo));
+            AddStep("add beatmap to collection", () => collectionManager.Collections[0].BeatmapHashes.Add(Beatmap.Value.BeatmapInfo.MD5Hash));
             AddAssert("button is minus", () => getAddOrRemoveButton(1).Icon.Equals(FontAwesome.Solid.MinusSquare));
 
-            AddStep("remove beatmap from collection", () => collectionManager.Collections[0].Beatmaps.Clear());
+            AddStep("remove beatmap from collection", () => collectionManager.Collections[0].BeatmapHashes.Clear());
             AddAssert("button is plus", () => getAddOrRemoveButton(1).Icon.Equals(FontAwesome.Solid.PlusSquare));
         }
 
@@ -169,11 +169,11 @@ namespace osu.Game.Tests.Visual.SongSelect
             AddAssert("button is plus", () => getAddOrRemoveButton(1).Icon.Equals(FontAwesome.Solid.PlusSquare));
 
             addClickAddOrRemoveButtonStep(1);
-            AddAssert("collection contains beatmap", () => collectionManager.Collections[0].Beatmaps.Contains(Beatmap.Value.BeatmapInfo));
+            AddAssert("collection contains beatmap", () => collectionManager.Collections[0].BeatmapHashes.Contains(Beatmap.Value.BeatmapInfo.MD5Hash));
             AddAssert("button is minus", () => getAddOrRemoveButton(1).Icon.Equals(FontAwesome.Solid.MinusSquare));
 
             addClickAddOrRemoveButtonStep(1);
-            AddAssert("collection does not contain beatmap", () => !collectionManager.Collections[0].Beatmaps.Contains(Beatmap.Value.BeatmapInfo));
+            AddAssert("collection does not contain beatmap", () => !collectionManager.Collections[0].BeatmapHashes.Contains(Beatmap.Value.BeatmapInfo.MD5Hash));
             AddAssert("button is plus", () => getAddOrRemoveButton(1).Icon.Equals(FontAwesome.Solid.PlusSquare));
         }
 

osu.Game/Beatmaps/BeatmapInfo.cs

@@ -90,6 +90,7 @@ namespace osu.Game.Beatmaps
 
         public double StarRating { get; set; }
 
+        [Indexed]
         public string MD5Hash { get; set; } = string.Empty;
 
         [JsonIgnore]

osu.Game/Collections/BeatmapCollection.cs

@@ -23,9 +23,9 @@ namespace osu.Game.Collections
         public readonly Bindable<string> Name = new Bindable<string>();
 
         /// <summary>
-        /// The beatmaps contained by the collection.
+        /// The <see cref="BeatmapInfo.MD5Hash"/>es of beatmaps contained by the collection.
         /// </summary>
-        public readonly BindableList<BeatmapInfo> Beatmaps = new BindableList<BeatmapInfo>();
+        public readonly BindableList<string> BeatmapHashes = new BindableList<string>();
 
         /// <summary>
         /// The date when this collection was last modified.
@@ -34,7 +34,7 @@ namespace osu.Game.Collections
 
         public BeatmapCollection()
         {
-            Beatmaps.CollectionChanged += (_, __) => onChange();
+            BeatmapHashes.CollectionChanged += (_, __) => onChange();
             Name.ValueChanged += _ => onChange();
         }
 

osu.Game/Collections/CollectionFilterDropdown.cs

@@ -38,7 +38,7 @@ namespace osu.Game.Collections
         }
 
         private readonly IBindableList<BeatmapCollection> collections = new BindableList<BeatmapCollection>();
-        private readonly IBindableList<BeatmapInfo> beatmaps = new BindableList<BeatmapInfo>();
+        private readonly IBindableList<string> beatmaps = new BindableList<string>();
         private readonly BindableList<CollectionFilterMenuItem> filters = new BindableList<CollectionFilterMenuItem>();
 
         [Resolved(CanBeNull = true)]
@@ -95,10 +95,10 @@ namespace osu.Game.Collections
             beatmaps.CollectionChanged -= filterBeatmapsChanged;
 
             if (filter.OldValue?.Collection != null)
-                beatmaps.UnbindFrom(filter.OldValue.Collection.Beatmaps);
+                beatmaps.UnbindFrom(filter.OldValue.Collection.BeatmapHashes);
 
             if (filter.NewValue?.Collection != null)
-                beatmaps.BindTo(filter.NewValue.Collection.Beatmaps);
+                beatmaps.BindTo(filter.NewValue.Collection.BeatmapHashes);
 
             beatmaps.CollectionChanged += filterBeatmapsChanged;
 
@@ -196,7 +196,7 @@ namespace osu.Game.Collections
             private IBindable<WorkingBeatmap> beatmap { get; set; }
 
             [CanBeNull]
-            private readonly BindableList<BeatmapInfo> collectionBeatmaps;
+            private readonly BindableList<string> collectionBeatmaps;
 
             [NotNull]
             private readonly Bindable<string> collectionName;
@@ -208,7 +208,7 @@ namespace osu.Game.Collections
             public CollectionDropdownMenuItem(MenuItem item)
                 : base(item)
             {
-                collectionBeatmaps = Item.Collection?.Beatmaps.GetBoundCopy();
+                collectionBeatmaps = Item.Collection?.BeatmapHashes.GetBoundCopy();
                 collectionName = Item.CollectionName.GetBoundCopy();
             }
 
@@ -258,7 +258,7 @@ namespace osu.Game.Collections
             {
                 Debug.Assert(collectionBeatmaps != null);
 
-                beatmapInCollection = collectionBeatmaps.Contains(beatmap.Value.BeatmapInfo);
+                beatmapInCollection = collectionBeatmaps.Contains(beatmap.Value.BeatmapInfo.MD5Hash);
 
                 addOrRemoveButton.Enabled.Value = !beatmap.IsDefault;
                 addOrRemoveButton.Icon = beatmapInCollection ? FontAwesome.Solid.MinusSquare : FontAwesome.Solid.PlusSquare;
@@ -285,8 +285,8 @@ namespace osu.Game.Collections
             {
                 Debug.Assert(collectionBeatmaps != null);
 
-                if (!collectionBeatmaps.Remove(beatmap.Value.BeatmapInfo))
+                if (!collectionBeatmaps.Remove(beatmap.Value.BeatmapInfo.MD5Hash))
-                    collectionBeatmaps.Add(beatmap.Value.BeatmapInfo);
+                    collectionBeatmaps.Add(beatmap.Value.BeatmapInfo.MD5Hash);
             }
 
             protected override Drawable CreateContent() => content = (Content)base.CreateContent();

osu.Game/Collections/CollectionManager.cs

@@ -13,7 +13,6 @@ using osu.Framework.Bindables;
 using osu.Framework.Graphics;
 using osu.Framework.Logging;
 using osu.Framework.Platform;
-using osu.Game.Beatmaps;
 using osu.Game.Database;
 using osu.Game.IO;
 using osu.Game.IO.Legacy;
@@ -40,9 +39,6 @@ namespace osu.Game.Collections
 
         public readonly BindableList<BeatmapCollection> Collections = new BindableList<BeatmapCollection>();
 
-        [Resolved]
-        private BeatmapManager beatmaps { get; set; }
-
         private readonly Storage storage;
 
         public CollectionManager(Storage storage)
@@ -173,10 +169,10 @@ namespace osu.Game.Collections
                         if (existing == null)
                             Collections.Add(existing = new BeatmapCollection { Name = { Value = newCol.Name.Value } });
 
-                        foreach (var newBeatmap in newCol.Beatmaps)
+                        foreach (string newBeatmap in newCol.BeatmapHashes)
                         {
-                            if (!existing.Beatmaps.Contains(newBeatmap))
+                            if (!existing.BeatmapHashes.Contains(newBeatmap))
-                                existing.Beatmaps.Add(newBeatmap);
+                                existing.BeatmapHashes.Add(newBeatmap);
                         }
                     }
 
@@ -226,9 +222,7 @@ namespace osu.Game.Collections
 
                             string checksum = sr.ReadString();
 
-                            var beatmap = beatmaps.QueryBeatmap(b => b.MD5Hash == checksum);
+                            collection.BeatmapHashes.Add(checksum);
-                            if (beatmap != null)
-                                collection.Beatmaps.Add(beatmap);
                         }
 
                         if (notification != null)
@@ -299,11 +293,12 @@ namespace osu.Game.Collections
                             {
                                 sw.Write(c.Name.Value);
 
-                                var beatmapsCopy = c.Beatmaps.ToArray();
+                                string[] beatmapsCopy = c.BeatmapHashes.ToArray();
+
                                 sw.Write(beatmapsCopy.Length);
 
-                                foreach (var b in beatmapsCopy)
+                                foreach (string b in beatmapsCopy)
-                                    sw.Write(b.MD5Hash);
+                                    sw.Write(b);
                             }
                         }
 

osu.Game/Collections/DeleteCollectionDialog.cs

@@ -13,7 +13,7 @@ namespace osu.Game.Collections
         public DeleteCollectionDialog(BeatmapCollection collection, Action deleteAction)
         {
             HeaderText = "Confirm deletion of";
-            BodyText = $"{collection.Name.Value} ({"beatmap".ToQuantity(collection.Beatmaps.Count)})";
+            BodyText = $"{collection.Name.Value} ({"beatmap".ToQuantity(collection.BeatmapHashes.Count)})";
 
             Icon = FontAwesome.Regular.TrashAlt;
 

osu.Game/Collections/DrawableCollectionListItem.cs

@@ -225,7 +225,7 @@ namespace osu.Game.Collections
             {
                 background.FlashColour(Color4.White, 150);
 
-                if (collection.Beatmaps.Count == 0)
+                if (collection.BeatmapHashes.Count == 0)
                     deleteCollection();
                 else
                     dialogOverlay?.Push(new DeleteCollectionDialog(collection, deleteCollection));

osu.Game/Graphics/OsuFont.cs

@@ -35,7 +35,10 @@ namespace osu.Game.Graphics
         /// <param name="fixedWidth">Whether all characters should be spaced the same distance apart.</param>
         /// <returns>The <see cref="FontUsage"/>.</returns>
         public static FontUsage GetFont(Typeface typeface = Typeface.Torus, float size = DEFAULT_FONT_SIZE, FontWeight weight = FontWeight.Medium, bool italics = false, bool fixedWidth = false)
-            => new FontUsage(GetFamilyString(typeface), size, GetWeightString(typeface, weight), getItalics(italics), fixedWidth);
+        {
+            string familyString = GetFamilyString(typeface);
+            return new FontUsage(familyString, size, GetWeightString(familyString, weight), getItalics(italics), fixedWidth);
+        }
 
         private static bool getItalics(in bool italicsRequested)
         {
@@ -54,16 +57,16 @@ namespace osu.Game.Graphics
             switch (typeface)
             {
                 case Typeface.Venera:
-                    return "Venera";
+                    return @"Venera";
 
                 case Typeface.Torus:
-                    return "Torus";
+                    return @"Torus";
 
                 case Typeface.TorusAlternate:
-                    return "Torus-Alternate";
+                    return @"Torus-Alternate";
 
                 case Typeface.Inter:
-                    return "Inter";
+                    return @"Inter";
             }
 
             return null;
@@ -72,25 +75,17 @@ namespace osu.Game.Graphics
         /// <summary>
         /// Retrieves the string representation of a <see cref="FontWeight"/>.
         /// </summary>
-        /// <param name="typeface">The <see cref="Typeface"/>.</param>
+        /// <param name="family">The font family.</param>
-        /// <param name="weight">The <see cref="FontWeight"/>.</param>
+        /// <param name="weight">The font weight.</param>
-        /// <returns>The string representation of <paramref name="weight"/> in the specified <paramref name="typeface"/>.</returns>
+        /// <returns>The string representation of <paramref name="weight"/> in the specified <paramref name="family"/>.</returns>
-        public static string GetWeightString(Typeface typeface, FontWeight weight)
+        public static string GetWeightString(string family, FontWeight weight)
         {
-            if (typeface == Typeface.Torus && weight == FontWeight.Medium)
+            if ((family == GetFamilyString(Typeface.Torus) || family == GetFamilyString(Typeface.TorusAlternate)) && weight == FontWeight.Medium)
                 // torus doesn't have a medium; fallback to regular.
                 weight = FontWeight.Regular;
 
-            return GetWeightString(GetFamilyString(typeface), weight);
+            return weight.ToString();
         }
-
-        /// <summary>
-        /// Retrieves the string representation of a <see cref="FontWeight"/>.
-        /// </summary>
-        /// <param name="family">The family string.</param>
-        /// <param name="weight">The <see cref="FontWeight"/>.</param>
-        /// <returns>The string representation of <paramref name="weight"/> in the specified <paramref name="family"/>.</returns>
-        public static string GetWeightString(string family, FontWeight weight) => weight.ToString();
     }
 
     public static class OsuFontExtensions

osu.Game/Localisation/GraphicsSettingsStrings.cs

@@ -34,11 +34,6 @@ namespace osu.Game.Localisation
         /// </summary>
         public static LocalisableString ShowFPS => new TranslatableString(getKey(@"show_fps"), @"Show FPS");
 
-        /// <summary>
-        /// "Using unlimited frame limiter can lead to stutters, bad performance and overheating. It will not improve perceived latency. "2x refresh rate" is recommended."
-        /// </summary>
-        public static LocalisableString UnlimitedFramesNote => new TranslatableString(getKey(@"unlimited_frames_note"), @"Using unlimited frame limiter can lead to stutters, bad performance and overheating. It will not improve perceived latency. ""2x refresh rate"" is recommended.");
-
         /// <summary>
         /// "Layout"
         /// </summary>

osu.Game/Online/ProductionEndpointConfiguration.cs

@@ -10,8 +10,8 @@ namespace osu.Game.Online
             WebsiteRootUrl = APIEndpointUrl = @"https://osu.ppy.sh";
             APIClientSecret = @"FGc9GAtyHzeQDshWP5Ah7dega8hJACAJpQtw6OXk";
             APIClientID = "5";
-            SpectatorEndpointUrl = "https://spectator2.ppy.sh/spectator";
+            SpectatorEndpointUrl = "https://spectator.ppy.sh/spectator";
-            MultiplayerEndpointUrl = "https://spectator2.ppy.sh/multiplayer";
+            MultiplayerEndpointUrl = "https://spectator.ppy.sh/multiplayer";
         }
     }
 }

osu.Game/Overlays/Music/Playlist.cs

@@ -30,7 +30,15 @@ namespace osu.Game.Overlays.Music
             var items = (SearchContainer<RearrangeableListItem<Live<BeatmapSetInfo>>>)ListContainer;
 
             foreach (var item in items.OfType<PlaylistItem>())
-                item.InSelectedCollection = criteria.Collection?.Beatmaps.Any(b => item.Model.ID == b.BeatmapSet?.ID) ?? true;
+            {
+                if (criteria.Collection == null)
+                    item.InSelectedCollection = true;
+                else
+                {
+                    item.InSelectedCollection = item.Model.Value.Beatmaps.Select(b => b.MD5Hash)
+                                                    .Any(criteria.Collection.BeatmapHashes.Contains);
+                }
+            }
 
             items.SearchTerm = criteria.SearchText;
         }

osu.Game/Overlays/Settings/Sections/DebugSettings/GeneralSettings.cs

@@ -9,6 +9,7 @@ using osu.Framework.Screens;
 using osu.Game.Localisation;
 using osu.Game.Screens;
 using osu.Game.Screens.Import;
+using osu.Game.Screens.Utility;
 
 namespace osu.Game.Overlays.Settings.Sections.DebugSettings
 {
@@ -30,13 +31,18 @@ namespace osu.Game.Overlays.Settings.Sections.DebugSettings
                 {
                     LabelText = DebugSettingsStrings.BypassFrontToBackPass,
                     Current = config.GetBindable<bool>(DebugSetting.BypassFrontToBackPass)
+                },
+                new SettingsButton
+                {
+                    Text = DebugSettingsStrings.ImportFiles,
+                    Action = () => performer?.PerformFromScreen(menu => menu.Push(new FileImportScreen()))
+                },
+                new SettingsButton
+                {
+                    Text = @"Run latency certifier",
+                    Action = () => performer?.PerformFromScreen(menu => menu.Push(new LatencyCertifierScreen()))
                 }
             };
-            Add(new SettingsButton
-            {
-                Text = DebugSettingsStrings.ImportFiles,
-                Action = () => performer?.PerformFromScreen(menu => menu.Push(new FileImportScreen()))
-            });
         }
     }
 }

osu.Game/Overlays/Settings/Sections/Graphics/RendererSettings.cs

@@ -15,8 +15,6 @@ namespace osu.Game.Overlays.Settings.Sections.Graphics
     {
         protected override LocalisableString Header => GraphicsSettingsStrings.RendererHeader;
 
-        private SettingsEnumDropdown<FrameSync> frameLimiterDropdown;
-
         [BackgroundDependencyLoader]
         private void load(FrameworkConfigManager config, OsuConfigManager osuConfig)
         {
@@ -24,7 +22,7 @@ namespace osu.Game.Overlays.Settings.Sections.Graphics
             Children = new Drawable[]
             {
                 // TODO: this needs to be a custom dropdown at some point
-                frameLimiterDropdown = new SettingsEnumDropdown<FrameSync>
+                new SettingsEnumDropdown<FrameSync>
                 {
                     LabelText = GraphicsSettingsStrings.FrameLimiter,
                     Current = config.GetBindable<FrameSync>(FrameworkSetting.FrameSync)
@@ -41,24 +39,5 @@ namespace osu.Game.Overlays.Settings.Sections.Graphics
                 },
             };
         }
-
-        protected override void LoadComplete()
-        {
-            base.LoadComplete();
-
-            frameLimiterDropdown.Current.BindValueChanged(limit =>
-            {
-                switch (limit.NewValue)
-                {
-                    case FrameSync.Unlimited:
-                        frameLimiterDropdown.SetNoticeText(GraphicsSettingsStrings.UnlimitedFramesNote, true);
-                        break;
-
-                    default:
-                        frameLimiterDropdown.ClearNoticeText();
-                        break;
-                }
-            }, true);
-        }
     }
 }

osu.Game/Rulesets/Difficulty/Preprocessing/DifficultyHitObject.cs

@@ -15,9 +15,9 @@ namespace osu.Game.Rulesets.Difficulty.Preprocessing
         private readonly IReadOnlyList<DifficultyHitObject> difficultyHitObjects;
 
         /// <summary>
-        /// The position of this <see cref="DifficultyHitObject"/> in the <see cref="difficultyHitObjects"/> list.
+        /// The index of this <see cref="DifficultyHitObject"/> in the list of all <see cref="DifficultyHitObject"/>s.
         /// </summary>
-        public int Position;
+        public int Index;
 
         /// <summary>
         /// The <see cref="HitObject"/> this <see cref="DifficultyHitObject"/> wraps.
@@ -51,11 +51,11 @@ namespace osu.Game.Rulesets.Difficulty.Preprocessing
         /// <param name="lastObject">The last <see cref="HitObject"/> which occurs before <paramref name="hitObject"/> in the beatmap.</param>
         /// <param name="clockRate">The rate at which the gameplay clock is run at.</param>
         /// <param name="objects">The list of <see cref="DifficultyHitObject"/>s in the current beatmap.</param>
-        /// <param name="position">The position of this <see cref="DifficultyHitObject"/> in the <see cref="difficultyHitObjects"/> list.</param>
+        /// <param name="index">The index of this <see cref="DifficultyHitObject"/> in <paramref name="objects"/> list.</param>
-        public DifficultyHitObject(HitObject hitObject, HitObject lastObject, double clockRate, List<DifficultyHitObject> objects, int position)
+        public DifficultyHitObject(HitObject hitObject, HitObject lastObject, double clockRate, List<DifficultyHitObject> objects, int index)
         {
             difficultyHitObjects = objects;
-            Position = position;
+            Index = index;
             BaseObject = hitObject;
             LastObject = lastObject;
             DeltaTime = (hitObject.StartTime - lastObject.StartTime) / clockRate;
@@ -63,8 +63,8 @@ namespace osu.Game.Rulesets.Difficulty.Preprocessing
             EndTime = hitObject.GetEndTime() / clockRate;
         }
 
-        public DifficultyHitObject Previous(int backwardsIndex) => difficultyHitObjects.ElementAtOrDefault(Position - (backwardsIndex + 1));
+        public DifficultyHitObject Previous(int backwardsIndex) => difficultyHitObjects.ElementAtOrDefault(Index - (backwardsIndex + 1));
 
-        public DifficultyHitObject Next(int forwardsIndex) => difficultyHitObjects.ElementAtOrDefault(Position + (forwardsIndex + 1));
+        public DifficultyHitObject Next(int forwardsIndex) => difficultyHitObjects.ElementAtOrDefault(Index + (forwardsIndex + 1));
     }
 }

osu.Game/Rulesets/Difficulty/Skills/StrainSkill.cs

@@ -47,7 +47,7 @@ namespace osu.Game.Rulesets.Difficulty.Skills
         public sealed override void Process(DifficultyHitObject current)
         {
             // The first object doesn't generate a strain, so we begin with an incremented section end
-            if (current.Position == 0)
+            if (current.Index == 0)
                 currentSectionEnd = Math.Ceiling(current.StartTime / SectionLength) * SectionLength;
 
             while (current.StartTime > currentSectionEnd)

osu.Game/Screens/Select/Carousel/CarouselBeatmap.cs

@@ -72,7 +72,7 @@ namespace osu.Game.Screens.Select.Carousel
             }
 
             if (match)
-                match &= criteria.Collection?.Beatmaps.Contains(BeatmapInfo) ?? true;
+                match &= criteria.Collection?.BeatmapHashes.Contains(BeatmapInfo.MD5Hash) ?? true;
 
             if (match && criteria.RulesetCriteria != null)
                 match &= criteria.RulesetCriteria.Matches(BeatmapInfo);

osu.Game/Screens/Select/Carousel/DrawableCarouselBeatmap.cs

@@ -256,12 +256,12 @@ namespace osu.Game.Screens.Select.Carousel
             return new ToggleMenuItem(collection.Name.Value, MenuItemType.Standard, s =>
             {
                 if (s)
-                    collection.Beatmaps.Add(beatmapInfo);
+                    collection.BeatmapHashes.Add(beatmapInfo.MD5Hash);
                 else
-                    collection.Beatmaps.Remove(beatmapInfo);
+                    collection.BeatmapHashes.Remove(beatmapInfo.MD5Hash);
             })
             {
-                State = { Value = collection.Beatmaps.Contains(beatmapInfo) }
+                State = { Value = collection.BeatmapHashes.Contains(beatmapInfo.MD5Hash) }
             };
         }
 

osu.Game/Screens/Select/Carousel/DrawableCarouselBeatmapSet.cs

@@ -245,7 +245,7 @@ namespace osu.Game.Screens.Select.Carousel
 
             TernaryState state;
 
-            int countExisting = beatmapSet.Beatmaps.Count(b => collection.Beatmaps.Contains(b));
+            int countExisting = beatmapSet.Beatmaps.Count(b => collection.BeatmapHashes.Contains(b.MD5Hash));
 
             if (countExisting == beatmapSet.Beatmaps.Count)
                 state = TernaryState.True;
@@ -261,14 +261,14 @@ namespace osu.Game.Screens.Select.Carousel
                     switch (s)
                     {
                         case TernaryState.True:
-                            if (collection.Beatmaps.Contains(b))
+                            if (collection.BeatmapHashes.Contains(b.MD5Hash))
                                 continue;
 
-                            collection.Beatmaps.Add(b);
+                            collection.BeatmapHashes.Add(b.MD5Hash);
                             break;
 
                         case TernaryState.False:
-                            collection.Beatmaps.Remove(b);
+                            collection.BeatmapHashes.Remove(b.MD5Hash);
                             break;
                     }
                 }

osu.Game/Screens/Utility/ButtonWithKeyBind.cs

@@ -0,0 +1,53 @@
+// 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.
+
+#nullable enable
+using osu.Framework.Allocation;
+using osu.Framework.Input.Events;
+using osu.Framework.Localisation;
+using osu.Game.Graphics;
+using osu.Game.Overlays;
+using osu.Game.Overlays.Settings;
+using osuTK.Input;
+
+namespace osu.Game.Screens.Utility
+{
+    public class ButtonWithKeyBind : SettingsButton
+    {
+        private readonly Key key;
+
+        public ButtonWithKeyBind(Key key)
+        {
+            this.key = key;
+        }
+
+        public new LocalisableString Text
+        {
+            get => base.Text;
+            set => base.Text = $"{value} (Press {key.ToString().Replace("Number", string.Empty)})";
+        }
+
+        protected override bool OnKeyDown(KeyDownEvent e)
+        {
+            if (!e.Repeat && e.Key == key)
+            {
+                TriggerClick();
+                return true;
+            }
+
+            return base.OnKeyDown(e);
+        }
+
+        [Resolved]
+        private OverlayColourProvider overlayColourProvider { get; set; } = null!;
+
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            Height = 100;
+            SpriteText.Colour = overlayColourProvider.Background6;
+            SpriteText.Font = OsuFont.TorusAlternate.With(size: 34);
+        }
+    }
+}

osu.Game/Screens/Utility/CircleGameplay.cs

@@ -0,0 +1,240 @@
+// 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.
+
+#nullable enable
+
+using System;
+using System.Collections.Generic;
+using osu.Framework.Allocation;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Graphics.Shapes;
+using osu.Framework.Input.Events;
+using osu.Framework.Input.States;
+using osu.Game.Beatmaps;
+using osu.Game.Graphics;
+using osu.Game.Rulesets.Objects;
+using osu.Game.Rulesets.Scoring;
+using osu.Game.Screens.Utility.SampleComponents;
+using osuTK;
+
+namespace osu.Game.Screens.Utility
+{
+    public class CircleGameplay : LatencySampleComponent
+    {
+        private int nextLocation;
+
+        private readonly List<HitEvent> hitEvents = new List<HitEvent>();
+
+        private double? lastGeneratedBeatTime;
+
+        private Container circles = null!;
+
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            InternalChildren = new Drawable[]
+            {
+                circles = new Container
+                {
+                    RelativeSizeAxes = Axes.Both,
+                },
+            };
+
+            SampleBPM.BindValueChanged(_ =>
+            {
+                circles.Clear();
+                lastGeneratedBeatTime = null;
+            });
+        }
+
+        protected override void UpdateAtLimitedRate(InputState inputState)
+        {
+            double beatLength = 60000 / SampleBPM.Value;
+
+            int nextBeat = (int)(Clock.CurrentTime / beatLength) + 1;
+
+            // We want to generate a few hit objects ahead of the current time (to allow them to animate).
+            double generateUpTo = (nextBeat + 2) * beatLength;
+
+            while (lastGeneratedBeatTime == null || lastGeneratedBeatTime < generateUpTo)
+            {
+                double time = ++nextBeat * beatLength;
+
+                if (time <= lastGeneratedBeatTime)
+                    continue;
+
+                newBeat(time);
+                lastGeneratedBeatTime = time;
+            }
+        }
+
+        private void newBeat(double time)
+        {
+            nextLocation++;
+
+            Vector2 location;
+
+            float adjust = SampleVisualSpacing.Value * 0.25f;
+
+            float spacingLow = 0.5f - adjust;
+            float spacingHigh = 0.5f + adjust;
+
+            switch (nextLocation % 4)
+            {
+                default:
+                    location = new Vector2(spacingLow, spacingLow);
+                    break;
+
+                case 1:
+                    location = new Vector2(spacingHigh, spacingHigh);
+                    break;
+
+                case 2:
+                    location = new Vector2(spacingHigh, spacingLow);
+                    break;
+
+                case 3:
+                    location = new Vector2(spacingLow, spacingHigh);
+                    break;
+            }
+
+            circles.Add(new SampleHitCircle(time)
+            {
+                RelativePositionAxes = Axes.Both,
+                Position = location,
+                Hit = hit,
+            });
+        }
+
+        private void hit(HitEvent h)
+        {
+            hitEvents.Add(h);
+        }
+
+        public class SampleHitCircle : LatencySampleComponent
+        {
+            public HitEvent? HitEvent;
+
+            public Action<HitEvent>? Hit { get; set; }
+
+            public readonly double HitTime;
+
+            private CircularContainer approach = null!;
+            private Circle circle = null!;
+
+            private const float size = 100;
+            private const float duration = 200;
+
+            public override bool ReceivePositionalInputAt(Vector2 screenSpacePos)
+                => circle.ReceivePositionalInputAt(screenSpacePos);
+
+            public SampleHitCircle(double hitTime)
+            {
+                HitTime = hitTime;
+
+                Origin = Anchor.Centre;
+                AutoSizeAxes = Axes.Both;
+                AlwaysPresent = true;
+            }
+
+            [BackgroundDependencyLoader]
+            private void load(OsuColour colours)
+            {
+                InternalChildren = new Drawable[]
+                {
+                    circle = new Circle
+                    {
+                        Colour = OverlayColourProvider.Content1,
+                        Size = new Vector2(size),
+                        Anchor = Anchor.Centre,
+                        Origin = Anchor.Centre,
+                    },
+                    approach = new CircularContainer
+                    {
+                        BorderColour = colours.Blue,
+                        Size = new Vector2(size),
+                        Masking = true,
+                        BorderThickness = 4,
+                        Anchor = Anchor.Centre,
+                        Origin = Anchor.Centre,
+                        Children = new Drawable[]
+                        {
+                            new Box
+                            {
+                                Alpha = 0,
+                                AlwaysPresent = true,
+                                RelativeSizeAxes = Axes.Both,
+                            },
+                        }
+                    },
+                };
+            }
+
+            protected override bool OnMouseDown(MouseDownEvent e)
+            {
+                if (HitEvent != null)
+                    return false;
+
+                if (Math.Abs(Clock.CurrentTime - HitTime) > duration)
+                    return false;
+
+                attemptHit();
+                return true;
+            }
+
+            protected override bool OnKeyDown(KeyDownEvent e)
+            {
+                if (!IsActive.Value)
+                    return false;
+
+                if (Math.Abs(Clock.CurrentTime - HitTime) > duration)
+                    return false;
+
+                if (IsHovered)
+                    attemptHit();
+                return base.OnKeyDown(e);
+            }
+
+            protected override void UpdateAtLimitedRate(InputState inputState)
+            {
+                if (HitEvent == null)
+                {
+                    double preempt = (float)IBeatmapDifficultyInfo.DifficultyRange(SampleApproachRate.Value, 1800, 1200, 450);
+
+                    approach.Scale = new Vector2(1 + 4 * (float)MathHelper.Clamp((HitTime - Clock.CurrentTime) / preempt, 0, 100));
+                    Alpha = (float)MathHelper.Clamp((Clock.CurrentTime - HitTime + 600) / 400, 0, 1);
+
+                    if (Clock.CurrentTime > HitTime + duration)
+                        Expire();
+                }
+            }
+
+            private void attemptHit() => Schedule(() =>
+            {
+                if (HitEvent != null)
+                    return;
+
+                // in case it was hit outside of display range, show immediately
+                // so the user isn't confused.
+                this.FadeIn();
+
+                approach.Expire();
+
+                circle
+                    .FadeOut(duration)
+                    .ScaleTo(1.5f, duration);
+
+                HitEvent = new HitEvent(Clock.CurrentTime - HitTime, HitResult.Good, new HitObject
+                {
+                    HitWindows = new HitWindows(),
+                }, null, null);
+
+                Hit?.Invoke(HitEvent.Value);
+
+                this.Delay(duration).Expire();
+            });
+        }
+    }
+}

osu.Game/Screens/Utility/LatencyArea.cs

@@ -0,0 +1,150 @@
+// 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.
+
+#nullable enable
+
+using System;
+using osu.Framework.Allocation;
+using osu.Framework.Bindables;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Graphics.Shapes;
+using osu.Framework.Input.Events;
+using osu.Game.Overlays;
+using osu.Game.Screens.Utility.SampleComponents;
+using osuTK.Input;
+
+namespace osu.Game.Screens.Utility
+{
+    [Cached]
+    public class LatencyArea : CompositeDrawable
+    {
+        [Resolved]
+        private OverlayColourProvider overlayColourProvider { get; set; } = null!;
+
+        public Action? ReportUserBest { get; set; }
+
+        private Drawable? background;
+
+        private readonly Key key;
+
+        private Container visualContent = null!;
+
+        public readonly int? TargetFrameRate;
+
+        public readonly BindableBool IsActiveArea = new BindableBool();
+
+        public readonly Bindable<LatencyVisualMode> VisualMode = new Bindable<LatencyVisualMode>();
+
+        public LatencyArea(Key key, int? targetFrameRate)
+        {
+            this.key = key;
+            TargetFrameRate = targetFrameRate;
+
+            RelativeSizeAxes = Axes.Both;
+            Masking = true;
+        }
+
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            InternalChildren = new[]
+            {
+                background = new Box
+                {
+                    Colour = overlayColourProvider.Background6,
+                    RelativeSizeAxes = Axes.Both,
+                },
+                new ButtonWithKeyBind(key)
+                {
+                    Text = "Feels better",
+                    Y = 20,
+                    Width = 0.8f,
+                    Anchor = Anchor.TopCentre,
+                    Origin = Anchor.TopCentre,
+                    Action = () => ReportUserBest?.Invoke(),
+                },
+                visualContent = new Container
+                {
+                    RelativeSizeAxes = Axes.Both,
+                },
+            };
+
+            IsActiveArea.BindValueChanged(active =>
+            {
+                background.FadeColour(active.NewValue ? overlayColourProvider.Background4 : overlayColourProvider.Background6, 200, Easing.OutQuint);
+            }, true);
+
+            VisualMode.BindValueChanged(mode =>
+            {
+                switch (mode.NewValue)
+                {
+                    case LatencyVisualMode.Simple:
+                        visualContent.Children = new Drawable[]
+                        {
+                            new LatencyMovableBox
+                            {
+                                RelativeSizeAxes = Axes.Both,
+                            },
+                            new LatencyCursorContainer
+                            {
+                                RelativeSizeAxes = Axes.Both,
+                            },
+                        };
+                        break;
+
+                    case LatencyVisualMode.CircleGameplay:
+                        visualContent.Children = new Drawable[]
+                        {
+                            new CircleGameplay
+                            {
+                                RelativeSizeAxes = Axes.Both,
+                            },
+                            new LatencyCursorContainer
+                            {
+                                RelativeSizeAxes = Axes.Both,
+                            },
+                        };
+                        break;
+
+                    case LatencyVisualMode.ScrollingGameplay:
+                        visualContent.Children = new Drawable[]
+                        {
+                            new ScrollingGameplay
+                            {
+                                RelativeSizeAxes = Axes.Both,
+                            },
+                            new LatencyCursorContainer
+                            {
+                                RelativeSizeAxes = Axes.Both,
+                            },
+                        };
+                        break;
+
+                    default:
+                        throw new ArgumentOutOfRangeException();
+                }
+            }, true);
+        }
+
+        protected override bool OnMouseMove(MouseMoveEvent e)
+        {
+            IsActiveArea.Value = true;
+            return base.OnMouseMove(e);
+        }
+
+        private double lastFrameTime;
+
+        public override bool UpdateSubTree()
+        {
+            double elapsed = Clock.CurrentTime - lastFrameTime;
+            if (TargetFrameRate.HasValue && elapsed < 1000.0 / TargetFrameRate)
+                return false;
+
+            lastFrameTime = Clock.CurrentTime;
+
+            return base.UpdateSubTree();
+        }
+    }
+}

osu.Game/Screens/Utility/LatencyCertifierScreen.cs

@@ -0,0 +1,532 @@
+// 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.
+
+#nullable enable
+
+using System;
+using System.Diagnostics;
+using System.Linq;
+using osu.Framework.Allocation;
+using osu.Framework.Bindables;
+using osu.Framework.Configuration;
+using osu.Framework.Extensions.Color4Extensions;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Colour;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Graphics.Effects;
+using osu.Framework.Graphics.Shapes;
+using osu.Framework.Graphics.Sprites;
+using osu.Framework.Input.Events;
+using osu.Framework.Platform;
+using osu.Framework.Platform.Windows;
+using osu.Framework.Screens;
+using osu.Framework.Utils;
+using osu.Game.Graphics;
+using osu.Game.Graphics.Containers;
+using osu.Game.Graphics.Sprites;
+using osu.Game.Overlays;
+using osu.Game.Overlays.Settings;
+using osuTK;
+using osuTK.Input;
+
+namespace osu.Game.Screens.Utility
+{
+    [Cached]
+    public class LatencyCertifierScreen : OsuScreen
+    {
+        private FrameSync previousFrameSyncMode;
+        private double previousActiveHz;
+
+        private readonly OsuTextFlowContainer statusText;
+
+        public override bool HideOverlaysOnEnter => true;
+
+        public override bool CursorVisible => mainArea.Count == 0;
+
+        public override float BackgroundParallaxAmount => 0;
+
+        private readonly LinkFlowContainer explanatoryText;
+
+        private readonly Container<LatencyArea> mainArea;
+
+        private readonly Container resultsArea;
+
+        public readonly BindableDouble SampleBPM = new BindableDouble(120) { MinValue = 60, MaxValue = 300, Precision = 1 };
+        public readonly BindableDouble SampleApproachRate = new BindableDouble(9) { MinValue = 5, MaxValue = 12, Precision = 0.1 };
+        public readonly BindableFloat SampleVisualSpacing = new BindableFloat(0.5f) { MinValue = 0f, MaxValue = 1, Precision = 0.1f };
+
+        /// <summary>
+        /// The rate at which the game host should attempt to run.
+        /// </summary>
+        private const int target_host_update_frames = 4000;
+
+        [Cached]
+        private readonly OverlayColourProvider overlayColourProvider = new OverlayColourProvider(OverlayColourScheme.Orange);
+
+        [Resolved]
+        private OsuColour colours { get; set; } = null!;
+
+        [Resolved]
+        private FrameworkConfigManager config { get; set; } = null!;
+
+        public readonly Bindable<LatencyVisualMode> VisualMode = new Bindable<LatencyVisualMode>();
+
+        private const int rounds_to_complete = 5;
+
+        private const int rounds_to_complete_certified = 20;
+
+        /// <summary>
+        /// Whether we are now in certification mode and decreasing difficulty.
+        /// </summary>
+        private bool isCertifying;
+
+        private int totalRoundForNextResultsScreen => isCertifying ? rounds_to_complete_certified : rounds_to_complete;
+
+        private int attemptsAtCurrentDifficulty;
+        private int correctAtCurrentDifficulty;
+
+        public int DifficultyLevel { get; private set; } = 1;
+
+        private double lastPoll;
+        private int pollingMax;
+
+        private readonly FillFlowContainer settings;
+
+        [Resolved]
+        private GameHost host { get; set; } = null!;
+
+        [Resolved]
+        private MusicController musicController { get; set; } = null!;
+
+        public LatencyCertifierScreen()
+        {
+            InternalChildren = new Drawable[]
+            {
+                new Box
+                {
+                    Colour = overlayColourProvider.Background6,
+                    RelativeSizeAxes = Axes.Both,
+                },
+                mainArea = new Container<LatencyArea>
+                {
+                    RelativeSizeAxes = Axes.Both,
+                },
+                // Make sure the edge between the two comparisons can't be used to ascertain latency.
+                new Box
+                {
+                    Name = "separator",
+                    Colour = ColourInfo.GradientHorizontal(overlayColourProvider.Background6, overlayColourProvider.Background6.Opacity(0)),
+                    Width = 100,
+                    RelativeSizeAxes = Axes.Y,
+                    Anchor = Anchor.TopCentre,
+                    Origin = Anchor.TopLeft,
+                },
+                new Box
+                {
+                    Name = "separator",
+                    Colour = ColourInfo.GradientHorizontal(overlayColourProvider.Background6.Opacity(0), overlayColourProvider.Background6),
+                    Width = 100,
+                    RelativeSizeAxes = Axes.Y,
+                    Anchor = Anchor.TopCentre,
+                    Origin = Anchor.TopRight,
+                },
+                settings = new FillFlowContainer
+                {
+                    Name = "Settings",
+                    AutoSizeAxes = Axes.Y,
+                    Width = 800,
+                    Padding = new MarginPadding(10),
+                    Spacing = new Vector2(2),
+                    Direction = FillDirection.Vertical,
+                    Anchor = Anchor.BottomCentre,
+                    Origin = Anchor.BottomCentre,
+                    Children = new Drawable[]
+                    {
+                        explanatoryText = new LinkFlowContainer(cp => cp.Font = OsuFont.Default.With(size: 20))
+                        {
+                            AutoSizeAxes = Axes.Y,
+                            RelativeSizeAxes = Axes.X,
+                            Anchor = Anchor.TopCentre,
+                            Origin = Anchor.TopCentre,
+                            TextAnchor = Anchor.TopCentre,
+                        },
+                        new SettingsSlider<double>
+                        {
+                            Anchor = Anchor.TopCentre,
+                            Origin = Anchor.TopCentre,
+                            RelativeSizeAxes = Axes.None,
+                            Width = 400,
+                            LabelText = "bpm",
+                            Current = SampleBPM
+                        },
+                        new SettingsSlider<float>
+                        {
+                            Anchor = Anchor.TopCentre,
+                            Origin = Anchor.TopCentre,
+                            RelativeSizeAxes = Axes.None,
+                            Width = 400,
+                            LabelText = "visual spacing",
+                            Current = SampleVisualSpacing
+                        },
+                        new SettingsSlider<double>
+                        {
+                            Anchor = Anchor.TopCentre,
+                            Origin = Anchor.TopCentre,
+                            RelativeSizeAxes = Axes.None,
+                            Width = 400,
+                            LabelText = "approach rate",
+                            Current = SampleApproachRate
+                        },
+                    },
+                },
+                resultsArea = new Container
+                {
+                    RelativeSizeAxes = Axes.Both,
+                },
+                statusText = new OsuTextFlowContainer(cp => cp.Font = OsuFont.Default.With(size: 40))
+                {
+                    Anchor = Anchor.TopCentre,
+                    Origin = Anchor.TopCentre,
+                    TextAnchor = Anchor.TopCentre,
+                    Y = 150,
+                    RelativeSizeAxes = Axes.X,
+                    AutoSizeAxes = Axes.Y,
+                },
+            };
+
+            explanatoryText.AddParagraph(@"Welcome to the latency certifier!");
+            explanatoryText.AddParagraph(@"Do whatever you need to try and perceive the difference in latency, then choose your best side. Read more about the methodology ");
+            explanatoryText.AddLink("here", "https://github.com/ppy/osu/wiki/Latency-and-unlimited-frame-rates#methodology");
+            explanatoryText.AddParagraph(@"Use the arrow keys or Z/X/F/J to control the display.");
+            explanatoryText.AddParagraph(@"Tab key to change focus. Space to change display mode");
+        }
+
+        protected override bool OnMouseMove(MouseMoveEvent e)
+        {
+            if (lastPoll > 0 && Clock.CurrentTime != lastPoll)
+                pollingMax = (int)Math.Max(pollingMax, 1000 / (Clock.CurrentTime - lastPoll));
+            lastPoll = Clock.CurrentTime;
+            return base.OnMouseMove(e);
+        }
+
+        public override void OnEntering(ScreenTransitionEvent e)
+        {
+            base.OnEntering(e);
+
+            previousFrameSyncMode = config.Get<FrameSync>(FrameworkSetting.FrameSync);
+            previousActiveHz = host.UpdateThread.ActiveHz;
+            config.SetValue(FrameworkSetting.FrameSync, FrameSync.Unlimited);
+            host.UpdateThread.ActiveHz = target_host_update_frames;
+            host.AllowBenchmarkUnlimitedFrames = true;
+
+            musicController.Stop();
+        }
+
+        public override bool OnExiting(ScreenExitEvent e)
+        {
+            host.AllowBenchmarkUnlimitedFrames = false;
+            config.SetValue(FrameworkSetting.FrameSync, previousFrameSyncMode);
+            host.UpdateThread.ActiveHz = previousActiveHz;
+            return base.OnExiting(e);
+        }
+
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+            loadNextRound();
+        }
+
+        protected override bool OnKeyDown(KeyDownEvent e)
+        {
+            switch (e.Key)
+            {
+                case Key.Space:
+                    int availableModes = Enum.GetValues(typeof(LatencyVisualMode)).Length;
+                    VisualMode.Value = (LatencyVisualMode)(((int)VisualMode.Value + 1) % availableModes);
+                    return true;
+
+                case Key.Tab:
+                    var firstArea = mainArea.FirstOrDefault(a => !a.IsActiveArea.Value);
+                    if (firstArea != null)
+                        firstArea.IsActiveArea.Value = true;
+                    return true;
+            }
+
+            return base.OnKeyDown(e);
+        }
+
+        private void showResults()
+        {
+            mainArea.Clear();
+            resultsArea.Clear();
+            settings.Hide();
+
+            var displayMode = host.Window?.CurrentDisplayMode.Value;
+
+            string exclusive = "unknown";
+
+            if (host.Window is WindowsWindow windowsWindow)
+                exclusive = windowsWindow.FullscreenCapability.ToString();
+
+            statusText.Clear();
+
+            float successRate = (float)correctAtCurrentDifficulty / attemptsAtCurrentDifficulty;
+            bool isPass = successRate == 1;
+
+            statusText.AddParagraph($"You scored {correctAtCurrentDifficulty} out of {attemptsAtCurrentDifficulty} ({successRate:0%})!", cp => cp.Colour = isPass ? colours.Green : colours.Red);
+            statusText.AddParagraph($"Level {DifficultyLevel} ({mapDifficultyToTargetFrameRate(DifficultyLevel):N0} Hz)",
+                cp => cp.Font = OsuFont.Default.With(size: 24));
+
+            statusText.AddParagraph(string.Empty);
+            statusText.AddParagraph(string.Empty);
+            statusText.AddIcon(isPass ? FontAwesome.Regular.CheckCircle : FontAwesome.Regular.TimesCircle, cp => cp.Colour = isPass ? colours.Green : colours.Red);
+            statusText.AddParagraph(string.Empty);
+
+            if (!isPass && DifficultyLevel > 1)
+            {
+                statusText.AddParagraph("To complete certification, the difficulty level will now decrease until you can get 20 rounds correct in a row!",
+                    cp => cp.Font = OsuFont.Default.With(size: 24, weight: FontWeight.SemiBold));
+                statusText.AddParagraph(string.Empty);
+            }
+
+            statusText.AddParagraph($"Polling: {pollingMax} Hz Monitor: {displayMode?.RefreshRate ?? 0:N0} Hz Exclusive: {exclusive}",
+                cp => cp.Font = OsuFont.Default.With(size: 15, weight: FontWeight.SemiBold));
+
+            statusText.AddParagraph($"Input: {host.InputThread.Clock.FramesPerSecond} Hz "
+                                    + $"Update: {host.UpdateThread.Clock.FramesPerSecond} Hz "
+                                    + $"Draw: {host.DrawThread.Clock.FramesPerSecond} Hz"
+                , cp => cp.Font = OsuFont.Default.With(size: 15, weight: FontWeight.SemiBold));
+
+            if (isCertifying && isPass)
+            {
+                showCertifiedScreen();
+                return;
+            }
+
+            string cannotIncreaseReason = string.Empty;
+
+            if (mapDifficultyToTargetFrameRate(DifficultyLevel + 1) > target_host_update_frames)
+                cannotIncreaseReason = "You've reached the maximum level.";
+            else if (mapDifficultyToTargetFrameRate(DifficultyLevel + 1) > Clock.FramesPerSecond)
+                cannotIncreaseReason = "Game is not running fast enough to test this level";
+
+            FillFlowContainer buttonFlow;
+
+            resultsArea.Add(buttonFlow = new FillFlowContainer
+            {
+                RelativeSizeAxes = Axes.X,
+                AutoSizeAxes = Axes.Y,
+                Anchor = Anchor.BottomLeft,
+                Origin = Anchor.BottomLeft,
+                Spacing = new Vector2(20),
+                Padding = new MarginPadding(20),
+            });
+
+            if (isPass)
+            {
+                buttonFlow.Add(new ButtonWithKeyBind(Key.Enter)
+                {
+                    Text = "Continue to next level",
+                    BackgroundColour = colours.Green,
+                    Anchor = Anchor.Centre,
+                    Origin = Anchor.Centre,
+                    Action = () => changeDifficulty(DifficultyLevel + 1),
+                    Enabled = { Value = string.IsNullOrEmpty(cannotIncreaseReason) },
+                    TooltipText = cannotIncreaseReason
+                });
+            }
+            else
+            {
+                if (DifficultyLevel == 1)
+                {
+                    buttonFlow.Add(new ButtonWithKeyBind(Key.Enter)
+                    {
+                        Text = "Retry",
+                        TooltipText = "Are you even trying..?",
+                        BackgroundColour = colours.Pink2,
+                        Anchor = Anchor.Centre,
+                        Origin = Anchor.Centre,
+                        Action = () =>
+                        {
+                            isCertifying = false;
+                            changeDifficulty(1);
+                        },
+                    });
+                }
+                else
+                {
+                    buttonFlow.Add(new ButtonWithKeyBind(Key.Enter)
+                    {
+                        Text = "Begin certification at last level",
+                        BackgroundColour = colours.Yellow,
+                        Anchor = Anchor.Centre,
+                        Origin = Anchor.Centre,
+                        Action = () =>
+                        {
+                            isCertifying = true;
+                            changeDifficulty(DifficultyLevel - 1);
+                        },
+                        TooltipText = isPass
+                            ? $"Chain {rounds_to_complete_certified} rounds to confirm your perception!"
+                            : "You've reached your limits. Go to the previous level to complete certification!",
+                    });
+                }
+            }
+        }
+
+        private void showCertifiedScreen()
+        {
+            Drawable background;
+            Drawable certifiedText;
+
+            resultsArea.AddRange(new[]
+            {
+                background = new Box
+                {
+                    Colour = overlayColourProvider.Background4,
+                    RelativeSizeAxes = Axes.Both,
+                },
+                (certifiedText = new OsuSpriteText
+                {
+                    Alpha = 0,
+                    Font = OsuFont.TorusAlternate.With(size: 80, weight: FontWeight.Bold),
+                    Text = "Certified!",
+                    Blending = BlendingParameters.Additive,
+                }).WithEffect(new GlowEffect
+                {
+                    Colour = overlayColourProvider.Colour1,
+                    PadExtent = true
+                }).With(e =>
+                {
+                    e.Anchor = Anchor.Centre;
+                    e.Origin = Anchor.Centre;
+                }),
+                new OsuSpriteText
+                {
+                    Text = $"You should use a frame limiter with update rate of {mapDifficultyToTargetFrameRate(DifficultyLevel + 1)} Hz (or fps) for best results!",
+                    Anchor = Anchor.Centre,
+                    Origin = Anchor.Centre,
+                    Font = OsuFont.Torus.With(size: 24, weight: FontWeight.SemiBold),
+                    Y = 80,
+                }
+            });
+
+            background.FadeInFromZero(1000, Easing.OutQuint);
+
+            certifiedText.FadeInFromZero(500, Easing.InQuint);
+
+            certifiedText
+                .ScaleTo(10)
+                .ScaleTo(1, 600, Easing.InQuad)
+                .Then()
+                .ScaleTo(1.05f, 10000, Easing.OutQuint);
+        }
+
+        private void changeDifficulty(int difficulty)
+        {
+            Debug.Assert(difficulty > 0);
+
+            resultsArea.Clear();
+
+            correctAtCurrentDifficulty = 0;
+            attemptsAtCurrentDifficulty = 0;
+
+            pollingMax = 0;
+            lastPoll = 0;
+
+            DifficultyLevel = difficulty;
+
+            loadNextRound();
+        }
+
+        private void loadNextRound()
+        {
+            settings.Show();
+
+            attemptsAtCurrentDifficulty++;
+            statusText.Text = $"Level {DifficultyLevel}\nRound {attemptsAtCurrentDifficulty} of {totalRoundForNextResultsScreen}";
+
+            mainArea.Clear();
+
+            int betterSide = RNG.Next(0, 2);
+
+            mainArea.AddRange(new[]
+            {
+                new LatencyArea(Key.Number1, betterSide == 1 ? mapDifficultyToTargetFrameRate(DifficultyLevel) : (int?)null)
+                {
+                    Width = 0.5f,
+                    VisualMode = { BindTarget = VisualMode },
+                    IsActiveArea = { Value = true },
+                    ReportUserBest = () => recordResult(betterSide == 0),
+                },
+                new LatencyArea(Key.Number2, betterSide == 0 ? mapDifficultyToTargetFrameRate(DifficultyLevel) : (int?)null)
+                {
+                    Width = 0.5f,
+                    VisualMode = { BindTarget = VisualMode },
+                    Anchor = Anchor.TopRight,
+                    Origin = Anchor.TopRight,
+                    ReportUserBest = () => recordResult(betterSide == 1)
+                }
+            });
+
+            foreach (var area in mainArea)
+            {
+                area.IsActiveArea.BindValueChanged(active =>
+                {
+                    if (active.NewValue)
+                        mainArea.Children.First(a => a != area).IsActiveArea.Value = false;
+                });
+            }
+        }
+
+        private void recordResult(bool correct)
+        {
+            // Fading this out will improve the frame rate after the first round due to less text on screen.
+            explanatoryText.FadeOut(500, Easing.OutQuint);
+
+            if (correct)
+                correctAtCurrentDifficulty++;
+
+            if (attemptsAtCurrentDifficulty < totalRoundForNextResultsScreen)
+                loadNextRound();
+            else
+                showResults();
+        }
+
+        private static int mapDifficultyToTargetFrameRate(int difficulty)
+        {
+            switch (difficulty)
+            {
+                case 1:
+                    return 15;
+
+                case 2:
+                    return 30;
+
+                case 3:
+                    return 45;
+
+                case 4:
+                    return 60;
+
+                case 5:
+                    return 120;
+
+                case 6:
+                    return 240;
+
+                case 7:
+                    return 480;
+
+                case 8:
+                    return 720;
+
+                case 9:
+                    return 960;
+
+                default:
+                    return 1000 + ((difficulty - 10) * 500);
+            }
+        }
+    }
+}

osu.Game/Screens/Utility/LatencyVisualMode.cs

@@ -0,0 +1,13 @@
+// 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.
+
+#nullable enable
+namespace osu.Game.Screens.Utility
+{
+    public enum LatencyVisualMode
+    {
+        CircleGameplay,
+        ScrollingGameplay,
+        Simple,
+    }
+}

osu.Game/Screens/Utility/SampleComponents/LatencyCursorContainer.cs

@@ -0,0 +1,57 @@
+// 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.
+
+#nullable enable
+using osu.Framework.Allocation;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Shapes;
+using osu.Framework.Input.Events;
+using osu.Framework.Input.States;
+using osu.Game.Overlays;
+using osuTK;
+using osuTK.Input;
+
+namespace osu.Game.Screens.Utility.SampleComponents
+{
+    public class LatencyCursorContainer : LatencySampleComponent
+    {
+        private Circle cursor = null!;
+
+        [Resolved]
+        private OverlayColourProvider overlayColourProvider { get; set; } = null!;
+
+        public LatencyCursorContainer()
+        {
+            Masking = true;
+        }
+
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            InternalChild = cursor = new Circle
+            {
+                Size = new Vector2(40),
+                Origin = Anchor.Centre,
+                Colour = overlayColourProvider.Colour2,
+            };
+        }
+
+        protected override bool OnHover(HoverEvent e) => false;
+
+        protected override void UpdateAtLimitedRate(InputState inputState)
+        {
+            cursor.Colour = inputState.Mouse.IsPressed(MouseButton.Left) ? overlayColourProvider.Content1 : overlayColourProvider.Colour2;
+
+            if (IsActive.Value)
+            {
+                cursor.Position = ToLocalSpace(inputState.Mouse.Position);
+                cursor.Alpha = 1;
+            }
+            else
+            {
+                cursor.Alpha = 0;
+            }
+        }
+    }
+}

osu.Game/Screens/Utility/SampleComponents/LatencyMovableBox.cs

@@ -0,0 +1,84 @@
+// 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.
+
+#nullable enable
+
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Shapes;
+using osu.Framework.Input.Events;
+using osu.Framework.Input.States;
+using osuTK;
+using osuTK.Input;
+
+namespace osu.Game.Screens.Utility.SampleComponents
+{
+    public class LatencyMovableBox : LatencySampleComponent
+    {
+        private Box box = null!;
+
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            InternalChild = box = new Box
+            {
+                Size = new Vector2(40),
+                RelativePositionAxes = Axes.Both,
+                Position = new Vector2(0.5f),
+                Origin = Anchor.Centre,
+                Colour = OverlayColourProvider.Colour1,
+            };
+        }
+
+        protected override bool OnHover(HoverEvent e) => false;
+
+        private double? lastFrameTime;
+
+        protected override void UpdateAtLimitedRate(InputState inputState)
+        {
+            if (!IsActive.Value)
+            {
+                lastFrameTime = null;
+                box.Colour = OverlayColourProvider.Colour1;
+                return;
+            }
+
+            if (lastFrameTime != null)
+            {
+                float movementAmount = (float)(Clock.CurrentTime - lastFrameTime) / 400;
+
+                var buttons = inputState.Keyboard.Keys;
+
+                box.Colour = buttons.HasAnyButtonPressed ? OverlayColourProvider.Content1 : OverlayColourProvider.Colour1;
+
+                foreach (var key in buttons)
+                {
+                    switch (key)
+                    {
+                        case Key.F:
+                        case Key.Up:
+                            box.Y = MathHelper.Clamp(box.Y - movementAmount, 0.1f, 0.9f);
+                            break;
+
+                        case Key.J:
+                        case Key.Down:
+                            box.Y = MathHelper.Clamp(box.Y + movementAmount, 0.1f, 0.9f);
+                            break;
+
+                        case Key.Z:
+                        case Key.Left:
+                            box.X = MathHelper.Clamp(box.X - movementAmount, 0.1f, 0.9f);
+                            break;
+
+                        case Key.X:
+                        case Key.Right:
+                            box.X = MathHelper.Clamp(box.X + movementAmount, 0.1f, 0.9f);
+                            break;
+                    }
+                }
+            }
+
+            lastFrameTime = Clock.CurrentTime;
+        }
+    }
+}

osu.Game/Screens/Utility/SampleComponents/LatencySampleComponent.cs

@@ -0,0 +1,55 @@
+// 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.
+
+#nullable enable
+
+using osu.Framework.Allocation;
+using osu.Framework.Bindables;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Input;
+using osu.Framework.Input.States;
+using osu.Game.Overlays;
+
+namespace osu.Game.Screens.Utility.SampleComponents
+{
+    public abstract class LatencySampleComponent : CompositeDrawable
+    {
+        protected readonly BindableDouble SampleBPM = new BindableDouble();
+        protected readonly BindableDouble SampleApproachRate = new BindableDouble();
+        protected readonly BindableFloat SampleVisualSpacing = new BindableFloat();
+
+        protected readonly BindableBool IsActive = new BindableBool();
+
+        private InputManager inputManager = null!;
+
+        [Resolved]
+        private LatencyArea latencyArea { get; set; } = null!;
+
+        [Resolved]
+        protected OverlayColourProvider OverlayColourProvider { get; private set; } = null!;
+
+        [BackgroundDependencyLoader]
+        private void load(LatencyCertifierScreen latencyCertifierScreen)
+        {
+            SampleBPM.BindTo(latencyCertifierScreen.SampleBPM);
+            SampleApproachRate.BindTo(latencyCertifierScreen.SampleApproachRate);
+            SampleVisualSpacing.BindTo(latencyCertifierScreen.SampleVisualSpacing);
+        }
+
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            inputManager = GetContainingInputManager();
+            IsActive.BindTo(latencyArea.IsActiveArea);
+        }
+
+        protected sealed override void Update()
+        {
+            base.Update();
+            UpdateAtLimitedRate(inputManager.CurrentState);
+        }
+
+        protected abstract void UpdateAtLimitedRate(InputState inputState);
+    }
+}

osu.Game/Screens/Utility/ScrollingGameplay.cs

@@ -0,0 +1,201 @@
+// 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.
+
+#nullable enable
+using System;
+using System.Collections.Generic;
+using osu.Framework.Allocation;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Graphics.Shapes;
+using osu.Framework.Input.Events;
+using osu.Framework.Input.States;
+using osu.Game.Beatmaps;
+using osu.Game.Rulesets.Objects;
+using osu.Game.Rulesets.Scoring;
+using osu.Game.Screens.Utility.SampleComponents;
+using osuTK;
+using osuTK.Input;
+
+namespace osu.Game.Screens.Utility
+{
+    public class ScrollingGameplay : LatencySampleComponent
+    {
+        private const float judgement_position = 0.8f;
+        private const float bar_height = 20;
+
+        private int nextLocation;
+
+        private readonly List<HitEvent> hitEvents = new List<HitEvent>();
+
+        private double? lastGeneratedBeatTime;
+
+        private Container circles = null!;
+
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            InternalChildren = new Drawable[]
+            {
+                new Box
+                {
+                    Name = "judgement bar",
+                    Colour = OverlayColourProvider.Content2,
+                    RelativeSizeAxes = Axes.X,
+                    RelativePositionAxes = Axes.Y,
+                    Y = judgement_position,
+                    Height = bar_height,
+                },
+                circles = new Container
+                {
+                    RelativeSizeAxes = Axes.Both,
+                },
+            };
+
+            SampleBPM.BindValueChanged(_ =>
+            {
+                circles.Clear();
+                lastGeneratedBeatTime = null;
+            });
+        }
+
+        protected override void UpdateAtLimitedRate(InputState inputState)
+        {
+            double beatLength = 60000 / SampleBPM.Value;
+
+            int nextBeat = (int)(Clock.CurrentTime / beatLength) + 1;
+
+            // We want to generate a few hit objects ahead of the current time (to allow them to animate).
+            double generateUpTo = (nextBeat + 2) * beatLength;
+
+            while (lastGeneratedBeatTime == null || lastGeneratedBeatTime < generateUpTo)
+            {
+                double time = ++nextBeat * beatLength;
+
+                if (time <= lastGeneratedBeatTime)
+                    continue;
+
+                newBeat(time);
+                lastGeneratedBeatTime = time;
+            }
+        }
+
+        private void newBeat(double time)
+        {
+            const float columns = 4;
+
+            float adjustedXPos = ((1f + nextLocation++ % columns) - columns / 2) / columns;
+
+            circles.Add(new SampleNote(time)
+            {
+                RelativePositionAxes = Axes.Both,
+                X = 0.5f + SampleVisualSpacing.Value * (adjustedXPos * 0.5f),
+                Scale = new Vector2(0.4f + (0.8f * SampleVisualSpacing.Value), 1),
+                Hit = hit,
+            });
+        }
+
+        private void hit(HitEvent h)
+        {
+            hitEvents.Add(h);
+        }
+
+        public class SampleNote : LatencySampleComponent
+        {
+            public HitEvent? HitEvent;
+
+            public Action<HitEvent>? Hit { get; set; }
+
+            public readonly double HitTime;
+
+            private Box box = null!;
+
+            private const float size = 100;
+            private const float duration = 200;
+
+            public SampleNote(double hitTime)
+            {
+                HitTime = hitTime;
+
+                Origin = Anchor.Centre;
+                AutoSizeAxes = Axes.Both;
+                AlwaysPresent = true;
+            }
+
+            [BackgroundDependencyLoader]
+            private void load()
+            {
+                InternalChildren = new Drawable[]
+                {
+                    box = new Box
+                    {
+                        Colour = OverlayColourProvider.Content1,
+                        Size = new Vector2(size, bar_height),
+                        Anchor = Anchor.Centre,
+                        Origin = Anchor.Centre,
+                    },
+                };
+            }
+
+            protected override bool OnKeyDown(KeyDownEvent e)
+            {
+                if (!IsActive.Value)
+                    return false;
+
+                if (Math.Abs(Clock.CurrentTime - HitTime) > duration)
+                    return false;
+
+                // Allow using any key that isn't used by the latency certifier itself.
+                switch (e.Key)
+                {
+                    case Key.Space:
+                    case Key.Number1:
+                    case Key.Number2:
+                    case Key.Tab:
+                        return false;
+                }
+
+                attemptHit();
+                return true;
+            }
+
+            protected override void UpdateAtLimitedRate(InputState inputState)
+            {
+                if (HitEvent == null)
+                {
+                    double preempt = (float)IBeatmapDifficultyInfo.DifficultyRange(SampleApproachRate.Value, 1800, 1200, 450);
+
+                    Alpha = (float)MathHelper.Clamp((Clock.CurrentTime - HitTime + 600) / 400, 0, 1);
+                    Y = judgement_position - (float)((HitTime - Clock.CurrentTime) / preempt);
+
+                    if (Clock.CurrentTime > HitTime + duration)
+                        Expire();
+                }
+            }
+
+            private void attemptHit() => Schedule(() =>
+            {
+                if (HitEvent != null)
+                    return;
+
+                // in case it was hit outside of display range, show immediately
+                // so the user isn't confused.
+                this.FadeIn();
+
+                box
+                    .FadeOut(duration / 2)
+                    .ScaleTo(1.5f, duration / 2);
+
+                HitEvent = new HitEvent(Clock.CurrentTime - HitTime, HitResult.Good, new HitObject
+                {
+                    HitWindows = new HitWindows(),
+                }, null, null);
+
+                Hit?.Invoke(HitEvent.Value);
+
+                this.Delay(duration).Expire();
+            });
+        }
+    }
+}

osu.Game/Stores/RealmArchiveModelImporter.cs

@@ -521,8 +521,7 @@ namespace osu.Game.Stores
             // for the best or worst, we copy and import files of a new import before checking whether
             // it is a duplicate. so to check if anything has changed, we can just compare all File IDs.
             getIDs(existing.Files).SequenceEqual(getIDs(import.Files)) &&
-            getFilenames(existing.Files).SequenceEqual(getFilenames(import.Files)) &&
+            getFilenames(existing.Files).SequenceEqual(getFilenames(import.Files));
-            checkAllFilesExist(existing);
 
         private bool checkAllFilesExist(TModel model) =>
             model.Files.All(f => Files.Storage.Exists(f.File.GetStoragePath()));

osu.Game/osu.Game.csproj

@@ -36,7 +36,7 @@
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
     <PackageReference Include="Realm" Version="10.14.0" />
-    <PackageReference Include="ppy.osu.Framework" Version="2022.605.0" />
+    <PackageReference Include="ppy.osu.Framework" Version="2022.611.0" />
     <PackageReference Include="ppy.osu.Game.Resources" Version="2022.527.0" />
     <PackageReference Include="Sentry" Version="3.17.1" />
     <PackageReference Include="SharpCompress" Version="0.31.0" />

osu.iOS.props

@@ -61,7 +61,7 @@
     <Reference Include="System.Net.Http" />
   </ItemGroup>
   <ItemGroup Label="Package References">
-    <PackageReference Include="ppy.osu.Framework.iOS" Version="2022.605.0" />
+    <PackageReference Include="ppy.osu.Framework.iOS" Version="2022.611.0" />
     <PackageReference Include="ppy.osu.Game.Resources" Version="2022.527.0" />
   </ItemGroup>
   <!-- See https://github.com/dotnet/runtime/issues/35988 (can be removed after Xamarin uses net6.0) -->
@@ -84,7 +84,7 @@
     <PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="5.0.14" />
     <PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite.Core" Version="5.0.14" />
     <PackageReference Include="Newtonsoft.Json" Version="13.0.1" />
-    <PackageReference Include="ppy.osu.Framework" Version="2022.605.0" />
+    <PackageReference Include="ppy.osu.Framework" Version="2022.611.0" />
     <PackageReference Include="SharpCompress" Version="0.31.0" />
     <PackageReference Include="NUnit" Version="3.13.3" />
     <PackageReference Include="System.ComponentModel.Annotations" Version="5.0.0" />