Merge branch 'master' into tournament-remove-minimum-window-size

osu.Game.Tests/Visual/Navigation/TestSceneBeatmapEditorNavigation.cs

@@ -9,6 +9,7 @@ using osu.Framework.Extensions.ObjectExtensions;
 using osu.Framework.Screens;
 using osu.Framework.Testing;
 using osu.Game.Beatmaps;
+using osu.Game.Configuration;
 using osu.Game.Database;
 using osu.Game.Rulesets.Mania;
 using osu.Game.Rulesets.Osu;
@@ -16,6 +17,7 @@ using osu.Game.Screens.Edit;
 using osu.Game.Screens.Edit.GameplayTest;
 using osu.Game.Screens.Menu;
 using osu.Game.Screens.Select;
+using osu.Game.Screens.Select.Filter;
 using osu.Game.Tests.Resources;
 using osuTK.Input;
 
@@ -203,6 +205,33 @@ namespace osu.Game.Tests.Visual.Navigation
             AddUntilStep("wait for music stopped", () => !Game.MusicController.IsPlaying);
         }
 
+        [TestCase(SortMode.Title)]
+        [TestCase(SortMode.Difficulty)]
+        public void TestSelectionRetainedOnExit(SortMode sortMode)
+        {
+            BeatmapSetInfo beatmapSet = null!;
+
+            AddStep("import test beatmap", () => Game.BeatmapManager.Import(TestResources.GetTestBeatmapForImport()).WaitSafely());
+            AddStep("retrieve beatmap", () => beatmapSet = Game.BeatmapManager.QueryBeatmapSet(set => !set.Protected).AsNonNull().Value.Detach());
+
+            AddStep($"set sort mode to {sortMode}", () => Game.LocalConfig.SetValue(OsuSetting.SongSelectSortingMode, sortMode));
+            AddStep("present beatmap", () => Game.PresentBeatmap(beatmapSet));
+            AddUntilStep("wait for song select",
+                () => Game.Beatmap.Value.BeatmapSetInfo.Equals(beatmapSet)
+                      && Game.ScreenStack.CurrentScreen is PlaySongSelect songSelect
+                      && songSelect.IsLoaded);
+
+            AddStep("open editor", () => ((PlaySongSelect)Game.ScreenStack.CurrentScreen).Edit(beatmapSet.Beatmaps.First(beatmap => beatmap.Ruleset.OnlineID == 0)));
+            AddUntilStep("wait for editor open", () => Game.ScreenStack.CurrentScreen is Editor editor && editor.ReadyForUse);
+
+            AddStep("exit editor", () => InputManager.Key(Key.Escape));
+            AddUntilStep("wait for editor exit", () => Game.ScreenStack.CurrentScreen is not Editor);
+
+            AddUntilStep("selection retained on song select",
+                () => Game.Beatmap.Value.BeatmapInfo.ID,
+                () => Is.EqualTo(beatmapSet.Beatmaps.First(b => b.Ruleset.OnlineID == 0).ID));
+        }
+
         private EditorBeatmap getEditorBeatmap() => getEditor().ChildrenOfType<EditorBeatmap>().Single();
 
         private Editor getEditor() => (Editor)Game.ScreenStack.CurrentScreen;

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

@@ -39,6 +39,7 @@ namespace osu.Game.Tests.Visual.SongSelect
         private BeatmapInfo currentSelection => carousel.SelectedBeatmapInfo;
 
         private const int set_count = 5;
+        private const int diff_count = 3;
 
         [BackgroundDependencyLoader]
         private void load(RulesetStore rulesets)
@@ -111,7 +112,7 @@ namespace osu.Game.Tests.Visual.SongSelect
         [Test]
         public void TestScrollPositionMaintainedOnAdd()
         {
-            loadBeatmaps(count: 1, randomDifficulties: false);
+            loadBeatmaps(setCount: 1);
 
             for (int i = 0; i < 10; i++)
             {
@@ -124,7 +125,7 @@ namespace osu.Game.Tests.Visual.SongSelect
         [Test]
         public void TestDeletion()
         {
-            loadBeatmaps(count: 5, randomDifficulties: true);
+            loadBeatmaps(setCount: 5, randomDifficulties: true);
 
             AddStep("remove first set", () => carousel.RemoveBeatmapSet(carousel.Items.Select(item => item.Item).OfType<CarouselBeatmapSet>().First().BeatmapSet));
             AddUntilStep("4 beatmap sets visible", () => this.ChildrenOfType<DrawableCarouselBeatmapSet>().Count(set => set.Alpha > 0) == 4);
@@ -133,7 +134,7 @@ namespace osu.Game.Tests.Visual.SongSelect
         [Test]
         public void TestScrollPositionMaintainedOnDelete()
         {
-            loadBeatmaps(count: 50, randomDifficulties: false);
+            loadBeatmaps(setCount: 50);
 
             for (int i = 0; i < 10; i++)
             {
@@ -150,7 +151,7 @@ namespace osu.Game.Tests.Visual.SongSelect
         [Test]
         public void TestManyPanels()
         {
-            loadBeatmaps(count: 5000, randomDifficulties: true);
+            loadBeatmaps(setCount: 5000, randomDifficulties: true);
         }
 
         [Test]
@@ -501,6 +502,33 @@ namespace osu.Game.Tests.Visual.SongSelect
             waitForSelection(set_count);
         }
 
+        [Test]
+        public void TestAddRemoveDifficultySort()
+        {
+            const int local_set_count = 2;
+            const int local_diff_count = 2;
+
+            loadBeatmaps(setCount: local_set_count, diffCount: local_diff_count);
+
+            AddStep("Sort by difficulty", () => carousel.Filter(new FilterCriteria { Sort = SortMode.Difficulty }, false));
+
+            checkVisibleItemCount(false, local_set_count * local_diff_count);
+
+            var firstAdded = TestResources.CreateTestBeatmapSetInfo(local_diff_count);
+
+            AddStep("Add new set", () => carousel.UpdateBeatmapSet(firstAdded));
+
+            checkVisibleItemCount(false, (local_set_count + 1) * local_diff_count);
+
+            AddStep("Remove set", () => carousel.RemoveBeatmapSet(firstAdded));
+
+            checkVisibleItemCount(false, (local_set_count) * local_diff_count);
+
+            setSelected(local_set_count, 1);
+
+            waitForSelection(local_set_count);
+        }
+
         [Test]
         public void TestSelectionEnteringFromEmptyRuleset()
         {
@@ -662,7 +690,7 @@ namespace osu.Game.Tests.Visual.SongSelect
 
                 for (int i = 0; i < 3; i++)
                 {
-                    var set = TestResources.CreateTestBeatmapSetInfo(3);
+                    var set = TestResources.CreateTestBeatmapSetInfo(diff_count);
 
                     // only need to set the first as they are a shared reference.
                     var beatmap = set.Beatmaps.First();
@@ -709,7 +737,7 @@ namespace osu.Game.Tests.Visual.SongSelect
 
                 for (int i = 0; i < 3; i++)
                 {
-                    var set = TestResources.CreateTestBeatmapSetInfo(3);
+                    var set = TestResources.CreateTestBeatmapSetInfo(diff_count);
 
                     // only need to set the first as they are a shared reference.
                     var beatmap = set.Beatmaps.First();
@@ -758,32 +786,54 @@ namespace osu.Game.Tests.Visual.SongSelect
         }
 
         [Test]
-        public void TestSortingWithFiltered()
+        public void TestSortingWithDifficultyFiltered()
         {
+            const int local_diff_count = 3;
+            const int local_set_count = 2;
+
             List<BeatmapSetInfo> sets = new List<BeatmapSetInfo>();
 
             AddStep("Populuate beatmap sets", () =>
             {
                 sets.Clear();
 
-                for (int i = 0; i < 3; i++)
+                for (int i = 0; i < local_set_count; i++)
                 {
-                    var set = TestResources.CreateTestBeatmapSetInfo(3);
+                    var set = TestResources.CreateTestBeatmapSetInfo(local_diff_count);
                     set.Beatmaps[0].StarRating = 3 - i;
-                    set.Beatmaps[2].StarRating = 6 + i;
+                    set.Beatmaps[1].StarRating = 6 + i;
                     sets.Add(set);
                 }
             });
 
             loadBeatmaps(sets);
 
+            AddStep("Sort by difficulty", () => carousel.Filter(new FilterCriteria { Sort = SortMode.Difficulty }, false));
+
+            checkVisibleItemCount(false, local_set_count * local_diff_count);
+            checkVisibleItemCount(true, 1);
+
             AddStep("Filter to normal", () => carousel.Filter(new FilterCriteria { Sort = SortMode.Difficulty, SearchText = "Normal" }, false));
-            AddAssert("Check first set at end", () => carousel.BeatmapSets.First().Equals(sets.Last()));
+            checkVisibleItemCount(false, local_set_count);
-            AddAssert("Check last set at start", () => carousel.BeatmapSets.Last().Equals(sets.First()));
+            checkVisibleItemCount(true, 1);
+
+            AddUntilStep("Check all visible sets have one normal", () =>
+            {
+                return carousel.Items.OfType<DrawableCarouselBeatmapSet>()
+                               .Where(p => p.IsPresent)
+                               .Count(p => ((CarouselBeatmapSet)p.Item)!.Beatmaps.Single().BeatmapInfo.DifficultyName.StartsWith("Normal", StringComparison.Ordinal)) == local_set_count;
+            });
 
             AddStep("Filter to insane", () => carousel.Filter(new FilterCriteria { Sort = SortMode.Difficulty, SearchText = "Insane" }, false));
-            AddAssert("Check first set at start", () => carousel.BeatmapSets.First().Equals(sets.First()));
+            checkVisibleItemCount(false, local_set_count);
-            AddAssert("Check last set at end", () => carousel.BeatmapSets.Last().Equals(sets.Last()));
+            checkVisibleItemCount(true, 1);
+
+            AddUntilStep("Check all visible sets have one insane", () =>
+            {
+                return carousel.Items.OfType<DrawableCarouselBeatmapSet>()
+                               .Where(p => p.IsPresent)
+                               .Count(p => ((CarouselBeatmapSet)p.Item)!.Beatmaps.Single().BeatmapInfo.DifficultyName.StartsWith("Insane", StringComparison.Ordinal)) == local_set_count;
+            });
         }
 
         [Test]
@@ -838,7 +888,7 @@ namespace osu.Game.Tests.Visual.SongSelect
 
             AddStep("create hidden set", () =>
             {
-                hidingSet = TestResources.CreateTestBeatmapSetInfo(3);
+                hidingSet = TestResources.CreateTestBeatmapSetInfo(diff_count);
                 hidingSet.Beatmaps[1].Hidden = true;
 
                 hiddenList.Clear();
@@ -885,7 +935,7 @@ namespace osu.Game.Tests.Visual.SongSelect
 
             AddStep("add mixed ruleset beatmapset", () =>
             {
-                testMixed = TestResources.CreateTestBeatmapSetInfo(3);
+                testMixed = TestResources.CreateTestBeatmapSetInfo(diff_count);
 
                 for (int i = 0; i <= 2; i++)
                 {
@@ -907,7 +957,7 @@ namespace osu.Game.Tests.Visual.SongSelect
             BeatmapSetInfo testSingle = null;
             AddStep("add single ruleset beatmapset", () =>
             {
-                testSingle = TestResources.CreateTestBeatmapSetInfo(3);
+                testSingle = TestResources.CreateTestBeatmapSetInfo(diff_count);
                 testSingle.Beatmaps.ForEach(b =>
                 {
                     b.Ruleset = rulesets.AvailableRulesets.ElementAt(1);
@@ -930,7 +980,7 @@ namespace osu.Game.Tests.Visual.SongSelect
                 manySets.Clear();
 
                 for (int i = 1; i <= 50; i++)
-                    manySets.Add(TestResources.CreateTestBeatmapSetInfo(3));
+                    manySets.Add(TestResources.CreateTestBeatmapSetInfo(diff_count));
             });
 
             loadBeatmaps(manySets);
@@ -955,6 +1005,43 @@ namespace osu.Game.Tests.Visual.SongSelect
             AddAssert("Selection was remembered", () => eagerSelectedIDs.Count == 1);
         }
 
+        [Test]
+        public void TestCarouselRemembersSelectionDifficultySort()
+        {
+            List<BeatmapSetInfo> manySets = new List<BeatmapSetInfo>();
+
+            AddStep("Populate beatmap sets", () =>
+            {
+                manySets.Clear();
+
+                for (int i = 1; i <= 50; i++)
+                    manySets.Add(TestResources.CreateTestBeatmapSetInfo(diff_count));
+            });
+
+            loadBeatmaps(manySets);
+
+            AddStep("Sort by difficulty", () => carousel.Filter(new FilterCriteria { Sort = SortMode.Difficulty }, false));
+
+            advanceSelection(direction: 1, diff: false);
+
+            for (int i = 0; i < 5; i++)
+            {
+                AddStep("Toggle non-matching filter", () =>
+                {
+                    carousel.Filter(new FilterCriteria { SearchText = Guid.NewGuid().ToString() }, false);
+                });
+
+                AddStep("Restore no filter", () =>
+                {
+                    carousel.Filter(new FilterCriteria(), false);
+                    eagerSelectedIDs.Add(carousel.SelectedBeatmapSet!.ID);
+                });
+            }
+
+            // always returns to same selection as long as it's available.
+            AddAssert("Selection was remembered", () => eagerSelectedIDs.Count == 1);
+        }
+
         [Test]
         public void TestFilteringByUserStarDifficulty()
         {
@@ -1081,8 +1168,8 @@ namespace osu.Game.Tests.Visual.SongSelect
             }
         }
 
-        private void loadBeatmaps(List<BeatmapSetInfo> beatmapSets = null, Func<FilterCriteria> initialCriteria = null, Action<BeatmapCarousel> carouselAdjust = null, int? count = null,
+        private void loadBeatmaps(List<BeatmapSetInfo> beatmapSets = null, Func<FilterCriteria> initialCriteria = null, Action<BeatmapCarousel> carouselAdjust = null,
-                                  bool randomDifficulties = false)
+                                  int? setCount = null, int? diffCount = null, bool randomDifficulties = false)
         {
             bool changed = false;
 
@@ -1090,11 +1177,11 @@ namespace osu.Game.Tests.Visual.SongSelect
             {
                 beatmapSets = new List<BeatmapSetInfo>();
 
-                for (int i = 1; i <= (count ?? set_count); i++)
+                for (int i = 1; i <= (setCount ?? set_count); i++)
                 {
                     beatmapSets.Add(randomDifficulties
                         ? TestResources.CreateTestBeatmapSetInfo()
-                        : TestResources.CreateTestBeatmapSetInfo(3));
+                        : TestResources.CreateTestBeatmapSetInfo(diffCount ?? diff_count));
                 }
             }
 

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

@@ -15,6 +15,7 @@ using osu.Game.Overlays;
 using osu.Game.Overlays.Dialog;
 using osu.Game.Screens.Select;
 using osu.Game.Screens.Select.Carousel;
+using osu.Game.Screens.Select.Filter;
 using osu.Game.Tests.Online;
 using osu.Game.Tests.Resources;
 using osuTK.Input;
@@ -192,6 +193,57 @@ namespace osu.Game.Tests.Visual.SongSelect
             AddStep("release mouse button", () => InputManager.ReleaseButton(MouseButton.Left));
         }
 
+        [Test]
+        public void TestSplitDisplay()
+        {
+            ArchiveDownloadRequest<IBeatmapSetInfo>? downloadRequest = null;
+
+            AddStep("set difficulty sort mode", () => carousel.Filter(new FilterCriteria { Sort = SortMode.Difficulty }));
+            AddStep("update online hash", () =>
+            {
+                testBeatmapSetInfo.Beatmaps.First().OnlineMD5Hash = "different hash";
+                testBeatmapSetInfo.Beatmaps.First().LastOnlineUpdate = DateTimeOffset.Now;
+
+                carousel.UpdateBeatmapSet(testBeatmapSetInfo);
+            });
+
+            AddUntilStep("multiple \"sets\" visible", () => carousel.ChildrenOfType<DrawableCarouselBeatmapSet>().Count(), () => Is.GreaterThan(1));
+            AddUntilStep("update button visible", getUpdateButton, () => Is.Not.Null);
+
+            AddStep("click button", () => getUpdateButton()?.TriggerClick());
+
+            AddUntilStep("wait for download started", () =>
+            {
+                downloadRequest = beatmapDownloader.GetExistingDownload(testBeatmapSetInfo);
+                return downloadRequest != null;
+            });
+
+            AddUntilStep("wait for button disabled", () => getUpdateButton()?.Enabled.Value == false);
+
+            AddUntilStep("progress download to completion", () =>
+            {
+                if (downloadRequest is TestSceneOnlinePlayBeatmapAvailabilityTracker.TestDownloadRequest testRequest)
+                {
+                    testRequest.SetProgress(testRequest.Progress + 0.1f);
+
+                    if (testRequest.Progress >= 1)
+                    {
+                        testRequest.TriggerSuccess();
+
+                        // usually this would be done by the import process.
+                        testBeatmapSetInfo.Beatmaps.First().MD5Hash = "different hash";
+                        testBeatmapSetInfo.Beatmaps.First().LastOnlineUpdate = DateTimeOffset.Now;
+
+                        // usually this would be done by a realm subscription.
+                        carousel.UpdateBeatmapSet(testBeatmapSetInfo);
+                        return true;
+                    }
+                }
+
+                return false;
+            });
+        }
+
         private BeatmapCarousel createCarousel()
         {
             return carousel = new BeatmapCarousel
@@ -199,7 +251,7 @@ namespace osu.Game.Tests.Visual.SongSelect
                 RelativeSizeAxes = Axes.Both,
                 BeatmapSets = new List<BeatmapSetInfo>
                 {
-                    (testBeatmapSetInfo = TestResources.CreateTestBeatmapSetInfo()),
+                    (testBeatmapSetInfo = TestResources.CreateTestBeatmapSetInfo(5)),
                 }
             };
         }

osu.Game.Tournament/SaveChangesOverlay.cs

@@ -7,13 +7,16 @@ using osu.Framework.Extensions.Color4Extensions;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Shapes;
+using osu.Framework.Input;
+using osu.Framework.Input.Bindings;
+using osu.Framework.Input.Events;
 using osu.Game.Graphics;
 using osu.Game.Online.Multiplayer;
 using osuTK;
 
 namespace osu.Game.Tournament
 {
-    internal partial class SaveChangesOverlay : CompositeDrawable
+    internal partial class SaveChangesOverlay : CompositeDrawable, IKeyBindingHandler<PlatformAction>
     {
         [Resolved]
         private TournamentGame tournamentGame { get; set; } = null!;
@@ -78,6 +81,21 @@ namespace osu.Game.Tournament
             scheduleNextCheck();
         }
 
+        public bool OnPressed(KeyBindingPressEvent<PlatformAction> e)
+        {
+            if (e.Action == PlatformAction.Save && !e.Repeat)
+            {
+                saveChangesButton.TriggerClick();
+                return true;
+            }
+
+            return false;
+        }
+
+        public void OnReleased(KeyBindingReleaseEvent<PlatformAction> e)
+        {
+        }
+
         private void scheduleNextCheck() => Scheduler.AddDelayed(() => checkForChanges().FireAndForget(), 1000);
 
         private void saveChanges()

osu.Game/Rulesets/Mods/ModExtensions.cs

@@ -21,8 +21,9 @@ namespace osu.Game.Rulesets.Mods
                 {
                     User = new APIUser
                     {
-                        Id = APIUser.SYSTEM_USER_ID,
+                        Id = replayData.User.OnlineID,
                         Username = replayData.User.Username,
+                        IsBot = replayData.User.IsBot,
                     }
                 }
             };

osu.Game/Screens/Ranking/ResultsScreen.cs

@@ -156,7 +156,7 @@ namespace osu.Game.Screens.Ranking
             if (Score != null)
             {
                 // only show flair / animation when arriving after watching a play that isn't autoplay.
-                bool shouldFlair = player != null && Score.Mods.All(m => m.UserPlayable);
+                bool shouldFlair = player != null && !Score.User.IsBot;
 
                 ScorePanelList.AddScore(Score, shouldFlair);
             }

osu.Game/Screens/Select/BeatmapCarousel.cs

@@ -78,6 +78,8 @@ namespace osu.Game.Screens.Select
 
         private CarouselBeatmapSet? selectedBeatmapSet;
 
+        private List<BeatmapSetInfo> originalBeatmapSetsDetached = new List<BeatmapSetInfo>();
+
         /// <summary>
         /// Raised when the <see cref="SelectedBeatmapInfo"/> is changed.
         /// </summary>
@@ -127,15 +129,37 @@ namespace osu.Game.Screens.Select
 
         private void loadBeatmapSets(IEnumerable<BeatmapSetInfo> beatmapSets)
         {
+            originalBeatmapSetsDetached = beatmapSets.Detach();
+
+            if (selectedBeatmapSet != null && !originalBeatmapSetsDetached.Contains(selectedBeatmapSet.BeatmapSet))
+                selectedBeatmapSet = null;
+
+            var selectedBeatmapBefore = selectedBeatmap?.BeatmapInfo;
+
             CarouselRoot newRoot = new CarouselRoot(this);
 
-            newRoot.AddItems(beatmapSets.Select(s => createCarouselSet(s.Detach())).OfType<CarouselBeatmapSet>());
+            if (beatmapsSplitOut)
+            {
+                var carouselBeatmapSets = originalBeatmapSetsDetached.SelectMany(s => s.Beatmaps).Select(b =>
+                {
+                    return createCarouselSet(new BeatmapSetInfo(new[] { b })
+                    {
+                        ID = b.BeatmapSet!.ID,
+                        OnlineID = b.BeatmapSet!.OnlineID
+                    });
+                }).OfType<CarouselBeatmapSet>();
+
+                newRoot.AddItems(carouselBeatmapSets);
+            }
+            else
+            {
+                var carouselBeatmapSets = originalBeatmapSetsDetached.Select(createCarouselSet).OfType<CarouselBeatmapSet>();
+
+                newRoot.AddItems(carouselBeatmapSets);
+            }
 
             root = newRoot;
 
-            if (selectedBeatmapSet != null && !beatmapSets.Contains(selectedBeatmapSet.BeatmapSet))
-                selectedBeatmapSet = null;
-
             Scroll.Clear(false);
             itemsCache.Invalidate();
             ScrollToSelected();
@@ -144,6 +168,15 @@ namespace osu.Game.Screens.Select
 
             if (loadedTestBeatmaps)
                 signalBeatmapsLoaded();
+
+            // Restore selection
+            if (selectedBeatmapBefore != null && newRoot.BeatmapSetsByID.TryGetValue(selectedBeatmapBefore.BeatmapSet!.ID, out var newSelectionCandidates))
+            {
+                CarouselBeatmap? found = newSelectionCandidates.SelectMany(s => s.Beatmaps).SingleOrDefault(b => b.BeatmapInfo.ID == selectedBeatmapBefore.ID);
+
+                if (found != null)
+                    found.State.Value = CarouselItemState.Selected;
+            }
         }
 
         private readonly List<CarouselItem> visibleItems = new List<CarouselItem>();
@@ -330,8 +363,8 @@ namespace osu.Game.Screens.Select
 
                 // Only require to action here if the beatmap is missing.
                 // This avoids processing these events unnecessarily when new beatmaps are imported, for example.
-                if (root.BeatmapSetsByID.TryGetValue(beatmapSet.ID, out var existingSet)
+                if (root.BeatmapSetsByID.TryGetValue(beatmapSet.ID, out var existingSets)
-                    && existingSet.BeatmapSet.Beatmaps.All(b => b.ID != beatmapInfo.ID))
+                    && existingSets.SelectMany(s => s.Beatmaps).All(b => b.BeatmapInfo.ID != beatmapInfo.ID))
                 {
                     UpdateBeatmapSet(beatmapSet.Detach());
                 }
@@ -345,15 +378,20 @@ namespace osu.Game.Screens.Select
 
         private void removeBeatmapSet(Guid beatmapSetID) => Schedule(() =>
         {
-            if (!root.BeatmapSetsByID.TryGetValue(beatmapSetID, out var existingSet))
+            if (!root.BeatmapSetsByID.TryGetValue(beatmapSetID, out var existingSets))
                 return;
 
-            foreach (var beatmap in existingSet.Beatmaps)
+            originalBeatmapSetsDetached.RemoveAll(set => set.ID == beatmapSetID);
-                randomSelectedBeatmaps.Remove(beatmap);
 
-            previouslyVisitedRandomSets.Remove(existingSet);
+            foreach (var set in existingSets)
+            {
+                foreach (var beatmap in set.Beatmaps)
+                    randomSelectedBeatmaps.Remove(beatmap);
+                previouslyVisitedRandomSets.Remove(set);
+
+                root.RemoveItem(set);
+            }
 
-            root.RemoveItem(existingSet);
             itemsCache.Invalidate();
 
             if (!Scroll.UserScrolling)
@@ -366,26 +404,63 @@ namespace osu.Game.Screens.Select
         {
             Guid? previouslySelectedID = null;
 
+            originalBeatmapSetsDetached.RemoveAll(set => set.ID == beatmapSet.ID);
+            originalBeatmapSetsDetached.Add(beatmapSet.Detach());
+
             // If the selected beatmap is about to be removed, store its ID so it can be re-selected if required
             if (selectedBeatmapSet?.BeatmapSet.ID == beatmapSet.ID)
                 previouslySelectedID = selectedBeatmap?.BeatmapInfo.ID;
 
-            var newSet = createCarouselSet(beatmapSet);
+            var removedSets = root.RemoveItemsByID(beatmapSet.ID);
-            var removedSet = root.RemoveChild(beatmapSet.ID);
 
-            // If we don't remove this here, it may remain in a hidden state until scrolled off screen.
+            foreach (var removedSet in removedSets)
-            // Doesn't really affect anything during actual user interaction, but makes testing annoying.
-            var removedDrawable = Scroll.FirstOrDefault(c => c.Item == removedSet);
-            if (removedDrawable != null)
-                expirePanelImmediately(removedDrawable);
-
-            if (newSet != null)
             {
-                root.AddItem(newSet);
+                // If we don't remove this here, it may remain in a hidden state until scrolled off screen.
+                // Doesn't really affect anything during actual user interaction, but makes testing annoying.
+                var removedDrawable = Scroll.FirstOrDefault(c => c.Item == removedSet);
+                if (removedDrawable != null)
+                    expirePanelImmediately(removedDrawable);
+            }
+
+            if (beatmapsSplitOut)
+            {
+                var newSets = new List<CarouselBeatmapSet>();
+
+                foreach (var beatmap in beatmapSet.Beatmaps)
+                {
+                    var newSet = createCarouselSet(new BeatmapSetInfo(new[] { beatmap })
+                    {
+                        ID = beatmapSet.ID,
+                        OnlineID = beatmapSet.OnlineID
+                    });
+
+                    if (newSet != null)
+                    {
+                        newSets.Add(newSet);
+                        root.AddItem(newSet);
+                    }
+                }
 
                 // check if we can/need to maintain our current selection.
                 if (previouslySelectedID != null)
-                    select((CarouselItem?)newSet.Beatmaps.FirstOrDefault(b => b.BeatmapInfo.ID == previouslySelectedID) ?? newSet);
+                {
+                    var toSelect = newSets.FirstOrDefault(s => s.Beatmaps.Any(b => b.BeatmapInfo.ID == previouslySelectedID))
+                                   ?? newSets.FirstOrDefault();
+                    select(toSelect);
+                }
+            }
+            else
+            {
+                var newSet = createCarouselSet(beatmapSet);
+
+                if (newSet != null)
+                {
+                    root.AddItem(newSet);
+
+                    // check if we can/need to maintain our current selection.
+                    if (previouslySelectedID != null)
+                        select((CarouselItem?)newSet.Beatmaps.FirstOrDefault(b => b.BeatmapInfo.ID == previouslySelectedID) ?? newSet);
+                }
             }
 
             itemsCache.Invalidate();
@@ -632,6 +707,8 @@ namespace osu.Game.Screens.Select
             applyActiveCriteria(debounce);
         }
 
+        private bool beatmapsSplitOut;
+
         private void applyActiveCriteria(bool debounce, bool alwaysResetScrollPosition = true)
         {
             PendingFilter?.Cancel();
@@ -652,6 +729,13 @@ namespace osu.Game.Screens.Select
             {
                 PendingFilter = null;
 
+                if (activeCriteria.SplitOutDifficulties != beatmapsSplitOut)
+                {
+                    beatmapsSplitOut = activeCriteria.SplitOutDifficulties;
+                    loadBeatmapSets(originalBeatmapSetsDetached);
+                    return;
+                }
+
                 root.Filter(activeCriteria);
                 itemsCache.Invalidate();
 
@@ -1055,7 +1139,7 @@ namespace osu.Game.Screens.Select
             // May only be null during construction (State.Value set causes PerformSelection to be triggered).
             private readonly BeatmapCarousel? carousel;
 
-            public readonly Dictionary<Guid, CarouselBeatmapSet> BeatmapSetsByID = new Dictionary<Guid, CarouselBeatmapSet>();
+            public readonly Dictionary<Guid, List<CarouselBeatmapSet>> BeatmapSetsByID = new Dictionary<Guid, List<CarouselBeatmapSet>>();
 
             public CarouselRoot(BeatmapCarousel carousel)
             {
@@ -1069,20 +1153,25 @@ namespace osu.Game.Screens.Select
             public override void AddItem(CarouselItem i)
             {
                 CarouselBeatmapSet set = (CarouselBeatmapSet)i;
-                BeatmapSetsByID.Add(set.BeatmapSet.ID, set);
+                if (BeatmapSetsByID.TryGetValue(set.BeatmapSet.ID, out var sets))
+                    sets.Add(set);
+                else
+                    BeatmapSetsByID.Add(set.BeatmapSet.ID, new List<CarouselBeatmapSet> { set });
 
                 base.AddItem(i);
             }
 
-            public CarouselBeatmapSet? RemoveChild(Guid beatmapSetID)
+            public IEnumerable<CarouselBeatmapSet> RemoveItemsByID(Guid beatmapSetID)
             {
-                if (BeatmapSetsByID.TryGetValue(beatmapSetID, out var carouselBeatmapSet))
+                if (BeatmapSetsByID.TryGetValue(beatmapSetID, out var carouselBeatmapSets))
                 {
-                    RemoveItem(carouselBeatmapSet);
+                    foreach (var set in carouselBeatmapSets)
-                    return carouselBeatmapSet;
+                        RemoveItem(set);
+
+                    return carouselBeatmapSets;
                 }
 
-                return null;
+                return Enumerable.Empty<CarouselBeatmapSet>();
             }
 
             public override void RemoveItem(CarouselItem i)

osu.Game/Screens/Select/FilterCriteria.cs

@@ -19,6 +19,11 @@ namespace osu.Game.Screens.Select
         public GroupMode Group;
         public SortMode Sort;
 
+        /// <summary>
+        /// Whether the display of beatmap sets should be split apart per-difficulty for the current criteria.
+        /// </summary>
+        public bool SplitOutDifficulties => Sort == SortMode.Difficulty;
+
         public BeatmapSetInfo? SelectedBeatmapSet;
 
         public OptionalRange<double> StarDifficulty;