Merge branch 'master' into beatmap-carousel-refactor

.idea/.idea.osu.Desktop/.idea/modules.xml

@@ -2,7 +2,7 @@
 <project version="4">
   <component name="ProjectModuleManager">
     <modules>
-      <module fileurl="file://$PROJECT_DIR$/.idea/.idea.osu.Desktop/riderModule.iml" filepath="$PROJECT_DIR$/.idea/.idea.osu.Desktop/riderModule.iml" />
+      <module fileurl="file://$PROJECT_DIR$/.idea/.idea.osu.Desktop/.idea/riderModule.iml" filepath="$PROJECT_DIR$/.idea/.idea.osu.Desktop/.idea/riderModule.iml" />
     </modules>
   </component>
 </project>

osu.Android.props

@@ -51,7 +51,7 @@
     <Reference Include="Java.Interop" />
   </ItemGroup>
   <ItemGroup>
-    <PackageReference Include="ppy.osu.Game.Resources" Version="2020.904.0" />
+    <PackageReference Include="ppy.osu.Game.Resources" Version="2020.1016.0" />
     <PackageReference Include="ppy.osu.Framework.Android" Version="2020.1013.0" />
   </ItemGroup>
 </Project>

osu.Game.Rulesets.Catch/Skinning/CatchLegacySkinTransformer.cs

@@ -13,6 +13,11 @@ namespace osu.Game.Rulesets.Catch.Skinning
 {
     public class CatchLegacySkinTransformer : LegacySkinTransformer
     {
+        /// <summary>
+        /// For simplicity, let's use legacy combo font texture existence as a way to identify legacy skins from default.
+        /// </summary>
+        private bool providesComboCounter => this.HasFont(GetConfig<LegacySetting, string>(LegacySetting.ComboPrefix)?.Value ?? "score");
+
         public CatchLegacySkinTransformer(ISkinSource source)
             : base(source)
         {
@@ -20,6 +25,16 @@ namespace osu.Game.Rulesets.Catch.Skinning
 
         public override Drawable GetDrawableComponent(ISkinComponent component)
         {
+            if (component is HUDSkinComponent hudComponent)
+            {
+                switch (hudComponent.Component)
+                {
+                    case HUDSkinComponents.ComboCounter:
+                        // catch may provide its own combo counter; hide the default.
+                        return providesComboCounter ? Drawable.Empty() : null;
+                }
+            }
+
             if (!(component is CatchSkinComponent catchSkinComponent))
                 return null;
 
@@ -55,11 +70,9 @@ namespace osu.Game.Rulesets.Catch.Skinning
                            this.GetAnimation("fruit-ryuuta", true, true, true);
 
                 case CatchSkinComponents.CatchComboCounter:
-                    var comboFont = GetConfig<LegacySetting, string>(LegacySetting.ComboPrefix)?.Value ?? "score";
 
-                    // For simplicity, let's use legacy combo font texture existence as a way to identify legacy skins from default.
+                    if (providesComboCounter)
-                    if (this.HasFont(comboFont))
+                        return new LegacyCatchComboCounter(Source);
-                        return new LegacyComboCounter(Source);
 
                     break;
             }

osu.Game.Rulesets.Catch/Skinning/LegacyCatchComboCounter.cs

@@ -14,13 +14,13 @@ namespace osu.Game.Rulesets.Catch.Skinning
     /// <summary>
     /// A combo counter implementation that visually behaves almost similar to stable's osu!catch combo counter.
     /// </summary>
-    public class LegacyComboCounter : CompositeDrawable, ICatchComboCounter
+    public class LegacyCatchComboCounter : CompositeDrawable, ICatchComboCounter
     {
         private readonly LegacyRollingCounter counter;
 
         private readonly LegacyRollingCounter explosion;
 
-        public LegacyComboCounter(ISkin skin)
+        public LegacyCatchComboCounter(ISkin skin)
         {
             var fontName = skin.GetConfig<LegacySetting, string>(LegacySetting.ComboPrefix)?.Value ?? "score";
             var fontOverlap = skin.GetConfig<LegacySetting, float>(LegacySetting.ComboOverlap)?.Value ?? -2f;

osu.Game.Rulesets.Mania.Tests/ManiaDifficultyCalculatorTest.cs

@@ -13,7 +13,7 @@ namespace osu.Game.Rulesets.Mania.Tests
     {
         protected override string ResourceAssembly => "osu.Game.Rulesets.Mania";
 
-        [TestCase(2.3683365342338796d, "diffcalc-test")]
+        [TestCase(2.3449735700206298d, "diffcalc-test")]
         public void Test(double expected, string name)
             => base.Test(expected, name);
 

osu.Game.Rulesets.Mania/Beatmaps/ManiaBeatmap.cs

@@ -21,13 +21,20 @@ namespace osu.Game.Rulesets.Mania.Beatmaps
         /// </summary>
         public int TotalColumns => Stages.Sum(g => g.Columns);
 
+        /// <summary>
+        /// The total number of columns that were present in this <see cref="ManiaBeatmap"/> before any user adjustments.
+        /// </summary>
+        public readonly int OriginalTotalColumns;
+
         /// <summary>
         /// Creates a new <see cref="ManiaBeatmap"/>.
         /// </summary>
         /// <param name="defaultStage">The initial stages.</param>
-        public ManiaBeatmap(StageDefinition defaultStage)
+        /// <param name="originalTotalColumns">The total number of columns present before any user adjustments. Defaults to the total columns in <paramref name="defaultStage"/>.</param>
+        public ManiaBeatmap(StageDefinition defaultStage, int? originalTotalColumns = null)
         {
             Stages.Add(defaultStage);
+            OriginalTotalColumns = originalTotalColumns ?? defaultStage.Columns;
         }
 
         public override IEnumerable<BeatmapStatistic> GetStatistics()

osu.Game.Rulesets.Mania/Beatmaps/ManiaBeatmapConverter.cs

@@ -28,6 +28,8 @@ namespace osu.Game.Rulesets.Mania.Beatmaps
         public bool Dual;
         public readonly bool IsForCurrentRuleset;
 
+        private readonly int originalTargetColumns;
+
         // Internal for testing purposes
         internal FastRandom Random { get; private set; }
 
@@ -65,6 +67,8 @@ namespace osu.Game.Rulesets.Mania.Beatmaps
                 else
                     TargetColumns = Math.Max(4, Math.Min((int)roundedOverallDifficulty + 1, 7));
             }
+
+            originalTargetColumns = TargetColumns;
         }
 
         public override bool CanConvert() => Beatmap.HitObjects.All(h => h is IHasXPosition);
@@ -81,7 +85,7 @@ namespace osu.Game.Rulesets.Mania.Beatmaps
 
         protected override Beatmap<ManiaHitObject> CreateBeatmap()
         {
-            beatmap = new ManiaBeatmap(new StageDefinition { Columns = TargetColumns });
+            beatmap = new ManiaBeatmap(new StageDefinition { Columns = TargetColumns }, originalTargetColumns);
 
             if (Dual)
                 beatmap.Stages.Add(new StageDefinition { Columns = TargetColumns });

osu.Game.Rulesets.Mania/Difficulty/ManiaDifficultyAttributes.cs

@@ -8,5 +8,6 @@ namespace osu.Game.Rulesets.Mania.Difficulty
     public class ManiaDifficultyAttributes : DifficultyAttributes
     {
         public double GreatHitWindow;
+        public double ScoreMultiplier;
     }
 }

osu.Game.Rulesets.Mania/Difficulty/ManiaDifficultyCalculator.cs

@@ -1,6 +1,7 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using osu.Game.Beatmaps;
@@ -10,10 +11,12 @@ using osu.Game.Rulesets.Difficulty.Skills;
 using osu.Game.Rulesets.Mania.Beatmaps;
 using osu.Game.Rulesets.Mania.Difficulty.Preprocessing;
 using osu.Game.Rulesets.Mania.Difficulty.Skills;
+using osu.Game.Rulesets.Mania.MathUtils;
 using osu.Game.Rulesets.Mania.Mods;
 using osu.Game.Rulesets.Mania.Objects;
 using osu.Game.Rulesets.Mania.Scoring;
 using osu.Game.Rulesets.Mods;
+using osu.Game.Rulesets.Objects;
 using osu.Game.Rulesets.Scoring;
 
 namespace osu.Game.Rulesets.Mania.Difficulty
@@ -23,11 +26,13 @@ namespace osu.Game.Rulesets.Mania.Difficulty
         private const double star_scaling_factor = 0.018;
 
         private readonly bool isForCurrentRuleset;
+        private readonly double originalOverallDifficulty;
 
         public ManiaDifficultyCalculator(Ruleset ruleset, WorkingBeatmap beatmap)
             : base(ruleset, beatmap)
         {
             isForCurrentRuleset = beatmap.BeatmapInfo.Ruleset.Equals(ruleset.RulesetInfo);
+            originalOverallDifficulty = beatmap.BeatmapInfo.BaseDifficulty.OverallDifficulty;
         }
 
         protected override DifficultyAttributes CreateDifficultyAttributes(IBeatmap beatmap, Mod[] mods, Skill[] skills, double clockRate)
@@ -40,64 +45,33 @@ namespace osu.Game.Rulesets.Mania.Difficulty
 
             return new ManiaDifficultyAttributes
             {
-                StarRating = difficultyValue(skills) * star_scaling_factor,
+                StarRating = skills[0].DifficultyValue() * star_scaling_factor,
                 Mods = mods,
                 // Todo: This int cast is temporary to achieve 1:1 results with osu!stable, and should be removed in the future
-                GreatHitWindow = (int)(hitWindows.WindowFor(HitResult.Great)) / clockRate,
+                GreatHitWindow = (int)Math.Ceiling(getHitWindow300(mods) / clockRate),
+                ScoreMultiplier = getScoreMultiplier(beatmap, mods),
                 MaxCombo = beatmap.HitObjects.Sum(h => h is HoldNote ? 2 : 1),
                 Skills = skills
             };
         }
 
-        private double difficultyValue(Skill[] skills)
-        {
-            // Preprocess the strains to find the maximum overall + individual (aggregate) strain from each section
-            var overall = skills.OfType<Overall>().Single();
-            var aggregatePeaks = new List<double>(Enumerable.Repeat(0.0, overall.StrainPeaks.Count));
-
-            foreach (var individual in skills.OfType<Individual>())
-            {
-                for (int i = 0; i < individual.StrainPeaks.Count; i++)
-                {
-                    double aggregate = individual.StrainPeaks[i] + overall.StrainPeaks[i];
-
-                    if (aggregate > aggregatePeaks[i])
-                        aggregatePeaks[i] = aggregate;
-                }
-            }
-
-            aggregatePeaks.Sort((a, b) => b.CompareTo(a)); // Sort from highest to lowest strain.
-
-            double difficulty = 0;
-            double weight = 1;
-
-            // Difficulty is the weighted sum of the highest strains from every section.
-            foreach (double strain in aggregatePeaks)
-            {
-                difficulty += strain * weight;
-                weight *= 0.9;
-            }
-
-            return difficulty;
-        }
-
         protected override IEnumerable<DifficultyHitObject> CreateDifficultyHitObjects(IBeatmap beatmap, double clockRate)
         {
-            for (int i = 1; i < beatmap.HitObjects.Count; i++)
+            var sortedObjects = beatmap.HitObjects.ToArray();
-                yield return new ManiaDifficultyHitObject(beatmap.HitObjects[i], beatmap.HitObjects[i - 1], clockRate);
+
+            LegacySortHelper<HitObject>.Sort(sortedObjects, Comparer<HitObject>.Create((a, b) => (int)Math.Round(a.StartTime) - (int)Math.Round(b.StartTime)));
+
+            for (int i = 1; i < sortedObjects.Length; i++)
+                yield return new ManiaDifficultyHitObject(sortedObjects[i], sortedObjects[i - 1], clockRate);
         }
 
-        protected override Skill[] CreateSkills(IBeatmap beatmap)
+        // Sorting is done in CreateDifficultyHitObjects, since the full list of hitobjects is required.
+        protected override IEnumerable<DifficultyHitObject> SortObjects(IEnumerable<DifficultyHitObject> input) => input;
+
+        protected override Skill[] CreateSkills(IBeatmap beatmap) => new Skill[]
         {
-            int columnCount = ((ManiaBeatmap)beatmap).TotalColumns;
+            new Strain(((ManiaBeatmap)beatmap).TotalColumns)
-
+        };
-            var skills = new List<Skill> { new Overall(columnCount) };
-
-            for (int i = 0; i < columnCount; i++)
-                skills.Add(new Individual(i, columnCount));
-
-            return skills.ToArray();
-        }
 
         protected override Mod[] DifficultyAdjustmentMods
         {
@@ -122,12 +96,73 @@ namespace osu.Game.Rulesets.Mania.Difficulty
                     new ManiaModKey3(),
                     new ManiaModKey4(),
                     new ManiaModKey5(),
+                    new MultiMod(new ManiaModKey5(), new ManiaModDualStages()),
                     new ManiaModKey6(),
+                    new MultiMod(new ManiaModKey6(), new ManiaModDualStages()),
                     new ManiaModKey7(),
+                    new MultiMod(new ManiaModKey7(), new ManiaModDualStages()),
                     new ManiaModKey8(),
+                    new MultiMod(new ManiaModKey8(), new ManiaModDualStages()),
                     new ManiaModKey9(),
+                    new MultiMod(new ManiaModKey9(), new ManiaModDualStages()),
                 }).ToArray();
             }
         }
+
+        private int getHitWindow300(Mod[] mods)
+        {
+            if (isForCurrentRuleset)
+            {
+                double od = Math.Min(10.0, Math.Max(0, 10.0 - originalOverallDifficulty));
+                return applyModAdjustments(34 + 3 * od, mods);
+            }
+
+            if (Math.Round(originalOverallDifficulty) > 4)
+                return applyModAdjustments(34, mods);
+
+            return applyModAdjustments(47, mods);
+
+            static int applyModAdjustments(double value, Mod[] mods)
+            {
+                if (mods.Any(m => m is ManiaModHardRock))
+                    value /= 1.4;
+                else if (mods.Any(m => m is ManiaModEasy))
+                    value *= 1.4;
+
+                if (mods.Any(m => m is ManiaModDoubleTime))
+                    value *= 1.5;
+                else if (mods.Any(m => m is ManiaModHalfTime))
+                    value *= 0.75;
+
+                return (int)value;
+            }
+        }
+
+        private double getScoreMultiplier(IBeatmap beatmap, Mod[] mods)
+        {
+            double scoreMultiplier = 1;
+
+            foreach (var m in mods)
+            {
+                switch (m)
+                {
+                    case ManiaModNoFail _:
+                    case ManiaModEasy _:
+                    case ManiaModHalfTime _:
+                        scoreMultiplier *= 0.5;
+                        break;
+                }
+            }
+
+            var maniaBeatmap = (ManiaBeatmap)beatmap;
+            int diff = maniaBeatmap.TotalColumns - maniaBeatmap.OriginalTotalColumns;
+
+            if (diff > 0)
+                scoreMultiplier *= 0.9;
+            else if (diff < 0)
+                scoreMultiplier *= 0.9 + 0.04 * diff;
+
+            return scoreMultiplier;
+        }
     }
 }

osu.Game.Rulesets.Mania/Difficulty/Skills/Individual.cs

@@ -1,47 +0,0 @@
-// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
-// See the LICENCE file in the repository root for full licence text.
-
-using System.Linq;
-using osu.Game.Rulesets.Difficulty.Preprocessing;
-using osu.Game.Rulesets.Difficulty.Skills;
-using osu.Game.Rulesets.Mania.Difficulty.Preprocessing;
-using osu.Game.Rulesets.Objects;
-
-namespace osu.Game.Rulesets.Mania.Difficulty.Skills
-{
-    public class Individual : Skill
-    {
-        protected override double SkillMultiplier => 1;
-        protected override double StrainDecayBase => 0.125;
-
-        private readonly double[] holdEndTimes;
-
-        private readonly int column;
-
-        public Individual(int column, int columnCount)
-        {
-            this.column = column;
-
-            holdEndTimes = new double[columnCount];
-        }
-
-        protected override double StrainValueOf(DifficultyHitObject current)
-        {
-            var maniaCurrent = (ManiaDifficultyHitObject)current;
-            var endTime = maniaCurrent.BaseObject.GetEndTime();
-
-            try
-            {
-                if (maniaCurrent.BaseObject.Column != column)
-                    return 0;
-
-                // We give a slight bonus if something is held meanwhile
-                return holdEndTimes.Any(t => t > endTime) ? 2.5 : 2;
-            }
-            finally
-            {
-                holdEndTimes[maniaCurrent.BaseObject.Column] = endTime;
-            }
-        }
-    }
-}

osu.Game.Rulesets.Mania/Difficulty/Skills/Overall.cs

@@ -1,56 +0,0 @@
-// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
-// See the LICENCE file in the repository root for full licence text.
-
-using osu.Game.Rulesets.Difficulty.Preprocessing;
-using osu.Game.Rulesets.Difficulty.Skills;
-using osu.Game.Rulesets.Mania.Difficulty.Preprocessing;
-using osu.Game.Rulesets.Objects;
-
-namespace osu.Game.Rulesets.Mania.Difficulty.Skills
-{
-    public class Overall : Skill
-    {
-        protected override double SkillMultiplier => 1;
-        protected override double StrainDecayBase => 0.3;
-
-        private readonly double[] holdEndTimes;
-
-        private readonly int columnCount;
-
-        public Overall(int columnCount)
-        {
-            this.columnCount = columnCount;
-
-            holdEndTimes = new double[columnCount];
-        }
-
-        protected override double StrainValueOf(DifficultyHitObject current)
-        {
-            var maniaCurrent = (ManiaDifficultyHitObject)current;
-            var endTime = maniaCurrent.BaseObject.GetEndTime();
-
-            double holdFactor = 1.0; // Factor in case something else is held
-            double holdAddition = 0; // Addition to the current note in case it's a hold and has to be released awkwardly
-
-            for (int i = 0; i < columnCount; i++)
-            {
-                // If there is at least one other overlapping end or note, then we get an addition, buuuuuut...
-                if (current.BaseObject.StartTime < holdEndTimes[i] && endTime > holdEndTimes[i])
-                    holdAddition = 1.0;
-
-                // ... this addition only is valid if there is _no_ other note with the same ending.
-                // Releasing multiple notes at the same time is just as easy as releasing one
-                if (endTime == holdEndTimes[i])
-                    holdAddition = 0;
-
-                // We give a slight bonus if something is held meanwhile
-                if (holdEndTimes[i] > endTime)
-                    holdFactor = 1.25;
-            }
-
-            holdEndTimes[maniaCurrent.BaseObject.Column] = endTime;
-
-            return (1 + holdAddition) * holdFactor;
-        }
-    }
-}

osu.Game.Rulesets.Mania/Difficulty/Skills/Strain.cs

@@ -0,0 +1,80 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System;
+using osu.Framework.Utils;
+using osu.Game.Rulesets.Difficulty.Preprocessing;
+using osu.Game.Rulesets.Difficulty.Skills;
+using osu.Game.Rulesets.Mania.Difficulty.Preprocessing;
+using osu.Game.Rulesets.Objects;
+
+namespace osu.Game.Rulesets.Mania.Difficulty.Skills
+{
+    public class Strain : Skill
+    {
+        private const double individual_decay_base = 0.125;
+        private const double overall_decay_base = 0.30;
+
+        protected override double SkillMultiplier => 1;
+        protected override double StrainDecayBase => 1;
+
+        private readonly double[] holdEndTimes;
+        private readonly double[] individualStrains;
+
+        private double individualStrain;
+        private double overallStrain;
+
+        public Strain(int totalColumns)
+        {
+            holdEndTimes = new double[totalColumns];
+            individualStrains = new double[totalColumns];
+            overallStrain = 1;
+        }
+
+        protected override double StrainValueOf(DifficultyHitObject current)
+        {
+            var maniaCurrent = (ManiaDifficultyHitObject)current;
+            var endTime = maniaCurrent.BaseObject.GetEndTime();
+            var column = maniaCurrent.BaseObject.Column;
+
+            double holdFactor = 1.0; // Factor to all additional strains in case something else is held
+            double holdAddition = 0; // Addition to the current note in case it's a hold and has to be released awkwardly
+
+            // Fill up the holdEndTimes array
+            for (int i = 0; i < holdEndTimes.Length; ++i)
+            {
+                // If there is at least one other overlapping end or note, then we get an addition, buuuuuut...
+                if (Precision.DefinitelyBigger(holdEndTimes[i], maniaCurrent.BaseObject.StartTime, 1) && Precision.DefinitelyBigger(endTime, holdEndTimes[i], 1))
+                    holdAddition = 1.0;
+
+                // ... this addition only is valid if there is _no_ other note with the same ending. Releasing multiple notes at the same time is just as easy as releasing 1
+                if (Precision.AlmostEquals(endTime, holdEndTimes[i], 1))
+                    holdAddition = 0;
+
+                // We give a slight bonus to everything if something is held meanwhile
+                if (Precision.DefinitelyBigger(holdEndTimes[i], endTime, 1))
+                    holdFactor = 1.25;
+
+                // Decay individual strains
+                individualStrains[i] = applyDecay(individualStrains[i], current.DeltaTime, individual_decay_base);
+            }
+
+            holdEndTimes[column] = endTime;
+
+            // Increase individual strain in own column
+            individualStrains[column] += 2.0 * holdFactor;
+            individualStrain = individualStrains[column];
+
+            overallStrain = applyDecay(overallStrain, current.DeltaTime, overall_decay_base) + (1 + holdAddition) * holdFactor;
+
+            return individualStrain + overallStrain - CurrentStrain;
+        }
+
+        protected override double GetPeakStrain(double offset)
+            => applyDecay(individualStrain, offset - Previous[0].BaseObject.StartTime, individual_decay_base)
+               + applyDecay(overallStrain, offset - Previous[0].BaseObject.StartTime, overall_decay_base);
+
+        private double applyDecay(double value, double deltaTime, double decayBase)
+            => value * Math.Pow(decayBase, deltaTime / 1000);
+    }
+}

osu.Game.Rulesets.Mania/MathUtils/LegacySortHelper.cs

@@ -0,0 +1,165 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System;
+using System.Collections.Generic;
+using System.Diagnostics.Contracts;
+
+namespace osu.Game.Rulesets.Mania.MathUtils
+{
+    /// <summary>
+    /// Provides access to .NET4.0 unstable sorting methods.
+    /// </summary>
+    /// <remarks>
+    /// Source: https://referencesource.microsoft.com/#mscorlib/system/collections/generic/arraysorthelper.cs
+    /// Copyright (c) Microsoft Corporation.  All rights reserved.
+    /// </remarks>
+    internal static class LegacySortHelper<T>
+    {
+        private const int quick_sort_depth_threshold = 32;
+
+        public static void Sort(T[] keys, IComparer<T> comparer)
+        {
+            if (keys == null)
+                throw new ArgumentNullException(nameof(keys));
+
+            if (keys.Length == 0)
+                return;
+
+            comparer ??= Comparer<T>.Default;
+            depthLimitedQuickSort(keys, 0, keys.Length - 1, comparer, quick_sort_depth_threshold);
+        }
+
+        private static void depthLimitedQuickSort(T[] keys, int left, int right, IComparer<T> comparer, int depthLimit)
+        {
+            do
+            {
+                if (depthLimit == 0)
+                {
+                    heapsort(keys, left, right, comparer);
+                    return;
+                }
+
+                int i = left;
+                int j = right;
+
+                // pre-sort the low, middle (pivot), and high values in place.
+                // this improves performance in the face of already sorted data, or
+                // data that is made up of multiple sorted runs appended together.
+                int middle = i + ((j - i) >> 1);
+                swapIfGreater(keys, comparer, i, middle); // swap the low with the mid point
+                swapIfGreater(keys, comparer, i, j); // swap the low with the high
+                swapIfGreater(keys, comparer, middle, j); // swap the middle with the high
+
+                T x = keys[middle];
+
+                do
+                {
+                    while (comparer.Compare(keys[i], x) < 0) i++;
+                    while (comparer.Compare(x, keys[j]) < 0) j--;
+                    Contract.Assert(i >= left && j <= right, "(i>=left && j<=right)  Sort failed - Is your IComparer bogus?");
+                    if (i > j) break;
+
+                    if (i < j)
+                    {
+                        T key = keys[i];
+                        keys[i] = keys[j];
+                        keys[j] = key;
+                    }
+
+                    i++;
+                    j--;
+                } while (i <= j);
+
+                // The next iteration of the while loop is to "recursively" sort the larger half of the array and the
+                // following calls recrusively sort the smaller half.  So we subtrack one from depthLimit here so
+                // both sorts see the new value.
+                depthLimit--;
+
+                if (j - left <= right - i)
+                {
+                    if (left < j) depthLimitedQuickSort(keys, left, j, comparer, depthLimit);
+                    left = i;
+                }
+                else
+                {
+                    if (i < right) depthLimitedQuickSort(keys, i, right, comparer, depthLimit);
+                    right = j;
+                }
+            } while (left < right);
+        }
+
+        private static void heapsort(T[] keys, int lo, int hi, IComparer<T> comparer)
+        {
+            Contract.Requires(keys != null);
+            Contract.Requires(comparer != null);
+            Contract.Requires(lo >= 0);
+            Contract.Requires(hi > lo);
+            Contract.Requires(hi < keys.Length);
+
+            int n = hi - lo + 1;
+
+            for (int i = n / 2; i >= 1; i = i - 1)
+            {
+                downHeap(keys, i, n, lo, comparer);
+            }
+
+            for (int i = n; i > 1; i = i - 1)
+            {
+                swap(keys, lo, lo + i - 1);
+                downHeap(keys, 1, i - 1, lo, comparer);
+            }
+        }
+
+        private static void downHeap(T[] keys, int i, int n, int lo, IComparer<T> comparer)
+        {
+            Contract.Requires(keys != null);
+            Contract.Requires(comparer != null);
+            Contract.Requires(lo >= 0);
+            Contract.Requires(lo < keys.Length);
+
+            T d = keys[lo + i - 1];
+
+            while (i <= n / 2)
+            {
+                var child = 2 * i;
+
+                if (child < n && comparer.Compare(keys[lo + child - 1], keys[lo + child]) < 0)
+                {
+                    child++;
+                }
+
+                if (!(comparer.Compare(d, keys[lo + child - 1]) < 0))
+                    break;
+
+                keys[lo + i - 1] = keys[lo + child - 1];
+                i = child;
+            }
+
+            keys[lo + i - 1] = d;
+        }
+
+        private static void swap(T[] a, int i, int j)
+        {
+            if (i != j)
+            {
+                T t = a[i];
+                a[i] = a[j];
+                a[j] = t;
+            }
+        }
+
+        private static void swapIfGreater(T[] keys, IComparer<T> comparer, int a, int b)
+        {
+            if (a != b)
+            {
+                if (comparer.Compare(keys[a], keys[b]) > 0)
+                {
+                    T key = keys[a];
+                    keys[a] = keys[b];
+                    keys[b] = key;
+                }
+            }
+        }
+    }
+}

osu.Game.Rulesets.Mania/Mods/ManiaKeyMod.cs

@@ -39,6 +39,7 @@ namespace osu.Game.Rulesets.Mania.Mods
             typeof(ManiaModKey7),
             typeof(ManiaModKey8),
             typeof(ManiaModKey9),
+            typeof(ManiaModKey10),
         }.Except(new[] { GetType() }).ToArray();
     }
 }

osu.Game.Tests/Beatmaps/Formats/LegacyBeatmapEncoderTest.cs

@@ -30,7 +30,7 @@ namespace osu.Game.Tests.Beatmaps.Formats
     {
         private static readonly DllResourceStore beatmaps_resource_store = TestResources.GetStore();
 
-        private static IEnumerable<string> allBeatmaps = beatmaps_resource_store.GetAvailableResources().Where(res => res.EndsWith(".osu"));
+        private static IEnumerable<string> allBeatmaps = beatmaps_resource_store.GetAvailableResources().Where(res => res.EndsWith(".osu", StringComparison.Ordinal));
 
         [TestCaseSource(nameof(allBeatmaps))]
         public void TestEncodeDecodeStability(string name)

osu.Game.Tests/NonVisual/DifficultyAdjustmentModCombinationsTest.cs

@@ -94,6 +94,52 @@ namespace osu.Game.Tests.NonVisual
             Assert.IsTrue(combinations[2] is ModIncompatibleWithAofA);
         }
 
+        [Test]
+        public void TestMultiModFlattening()
+        {
+            var combinations = new TestLegacyDifficultyCalculator(new ModA(), new MultiMod(new ModB(), new ModC())).CreateDifficultyAdjustmentModCombinations();
+
+            Assert.AreEqual(4, combinations.Length);
+            Assert.IsTrue(combinations[0] is ModNoMod);
+            Assert.IsTrue(combinations[1] is ModA);
+            Assert.IsTrue(combinations[2] is MultiMod);
+            Assert.IsTrue(combinations[3] is MultiMod);
+
+            Assert.IsTrue(((MultiMod)combinations[2]).Mods[0] is ModA);
+            Assert.IsTrue(((MultiMod)combinations[2]).Mods[1] is ModB);
+            Assert.IsTrue(((MultiMod)combinations[2]).Mods[2] is ModC);
+            Assert.IsTrue(((MultiMod)combinations[3]).Mods[0] is ModB);
+            Assert.IsTrue(((MultiMod)combinations[3]).Mods[1] is ModC);
+        }
+
+        [Test]
+        public void TestIncompatibleThroughMultiMod()
+        {
+            var combinations = new TestLegacyDifficultyCalculator(new ModA(), new MultiMod(new ModB(), new ModIncompatibleWithA())).CreateDifficultyAdjustmentModCombinations();
+
+            Assert.AreEqual(3, combinations.Length);
+            Assert.IsTrue(combinations[0] is ModNoMod);
+            Assert.IsTrue(combinations[1] is ModA);
+            Assert.IsTrue(combinations[2] is MultiMod);
+
+            Assert.IsTrue(((MultiMod)combinations[2]).Mods[0] is ModB);
+            Assert.IsTrue(((MultiMod)combinations[2]).Mods[1] is ModIncompatibleWithA);
+        }
+
+        [Test]
+        public void TestIncompatibleWithSameInstanceViaMultiMod()
+        {
+            var combinations = new TestLegacyDifficultyCalculator(new ModA(), new MultiMod(new ModA(), new ModB())).CreateDifficultyAdjustmentModCombinations();
+
+            Assert.AreEqual(3, combinations.Length);
+            Assert.IsTrue(combinations[0] is ModNoMod);
+            Assert.IsTrue(combinations[1] is ModA);
+            Assert.IsTrue(combinations[2] is MultiMod);
+
+            Assert.IsTrue(((MultiMod)combinations[2]).Mods[0] is ModA);
+            Assert.IsTrue(((MultiMod)combinations[2]).Mods[1] is ModB);
+        }
+
         private class ModA : Mod
         {
             public override string Name => nameof(ModA);
@@ -112,6 +158,13 @@ namespace osu.Game.Tests.NonVisual
             public override Type[] IncompatibleMods => new[] { typeof(ModIncompatibleWithAAndB) };
         }
 
+        private class ModC : Mod
+        {
+            public override string Name => nameof(ModC);
+            public override string Acronym => nameof(ModC);
+            public override double ScoreMultiplier => 1;
+        }
+
         private class ModIncompatibleWithA : Mod
         {
             public override string Name => $"Incompatible With {nameof(ModA)}";

osu.Game.Tests/Resources/old-skin/skin.ini

@@ -0,0 +1,2 @@
+[General]
+Version: 1.0

osu.Game.Tests/Visual/Gameplay/TestSceneComboCounter.cs

@@ -0,0 +1,47 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System.Collections.Generic;
+using System.Linq;
+using NUnit.Framework;
+using osu.Framework.Testing;
+using osu.Game.Rulesets;
+using osu.Game.Rulesets.Osu;
+using osu.Game.Screens.Play.HUD;
+
+namespace osu.Game.Tests.Visual.Gameplay
+{
+    public class TestSceneComboCounter : SkinnableTestScene
+    {
+        private IEnumerable<SkinnableComboCounter> comboCounters => CreatedDrawables.OfType<SkinnableComboCounter>();
+
+        protected override Ruleset CreateRulesetForSkinProvider() => new OsuRuleset();
+
+        [SetUpSteps]
+        public void SetUpSteps()
+        {
+            AddStep("Create combo counters", () => SetContents(() =>
+            {
+                var comboCounter = new SkinnableComboCounter();
+                comboCounter.Current.Value = 1;
+                return comboCounter;
+            }));
+        }
+
+        [Test]
+        public void TestComboCounterIncrementing()
+        {
+            AddRepeatStep("increase combo", () =>
+            {
+                foreach (var counter in comboCounters)
+                    counter.Current.Value++;
+            }, 10);
+
+            AddStep("reset combo", () =>
+            {
+                foreach (var counter in comboCounters)
+                    counter.Current.Value = 0;
+            });
+        }
+    }
+}

osu.Game.Tests/Visual/Gameplay/TestSceneGameplaySamplePlayback.cs

@@ -26,7 +26,7 @@ namespace osu.Game.Tests.Visual.Gameplay
 
             AddStep("get variables", () =>
             {
-                gameplayClock = Player.ChildrenOfType<FrameStabilityContainer>().First().GameplayClock;
+                gameplayClock = Player.ChildrenOfType<FrameStabilityContainer>().First();
                 slider = Player.ChildrenOfType<DrawableSlider>().OrderBy(s => s.HitObject.StartTime).First();
                 samples = slider.ChildrenOfType<DrawableSample>().ToArray();
             });

osu.Game.Tests/Visual/Gameplay/TestSceneHUDOverlay.cs

@@ -2,23 +2,29 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System;
+using System.Collections.Generic;
 using System.Linq;
 using NUnit.Framework;
 using osu.Framework.Allocation;
+using osu.Framework.Extensions.IEnumerableExtensions;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Testing;
 using osu.Game.Configuration;
+using osu.Game.Rulesets;
 using osu.Game.Rulesets.Mods;
+using osu.Game.Rulesets.Osu;
 using osu.Game.Screens.Play;
 using osuTK.Input;
 
 namespace osu.Game.Tests.Visual.Gameplay
 {
-    public class TestSceneHUDOverlay : OsuManualInputManagerTestScene
+    public class TestSceneHUDOverlay : SkinnableTestScene
     {
         private HUDOverlay hudOverlay;
 
+        private IEnumerable<HUDOverlay> hudOverlays => CreatedDrawables.OfType<HUDOverlay>();
+
         // best way to check without exposing.
         private Drawable hideTarget => hudOverlay.KeyCounter;
         private FillFlowContainer<KeyCounter> keyCounterFlow => hudOverlay.KeyCounter.ChildrenOfType<FillFlowContainer<KeyCounter>>().First();
@@ -26,6 +32,24 @@ namespace osu.Game.Tests.Visual.Gameplay
         [Resolved]
         private OsuConfigManager config { get; set; }
 
+        [Test]
+        public void TestComboCounterIncrementing()
+        {
+            createNew();
+
+            AddRepeatStep("increase combo", () =>
+            {
+                foreach (var hud in hudOverlays)
+                    hud.ComboCounter.Current.Value++;
+            }, 10);
+
+            AddStep("reset combo", () =>
+            {
+                foreach (var hud in hudOverlays)
+                    hud.ComboCounter.Current.Value = 0;
+            });
+        }
+
         [Test]
         public void TestShownByDefault()
         {
@@ -45,7 +69,7 @@ namespace osu.Game.Tests.Visual.Gameplay
 
             createNew(h => h.OnLoadComplete += _ => initialAlpha = hideTarget.Alpha);
             AddUntilStep("wait for load", () => hudOverlay.IsAlive);
-            AddAssert("initial alpha was less than 1", () => initialAlpha != null && initialAlpha < 1);
+            AddAssert("initial alpha was less than 1", () => initialAlpha < 1);
         }
 
         [Test]
@@ -53,7 +77,7 @@ namespace osu.Game.Tests.Visual.Gameplay
         {
             createNew();
 
-            AddStep("set showhud false", () => hudOverlay.ShowHud.Value = false);
+            AddStep("set showhud false", () => hudOverlays.ForEach(h => h.ShowHud.Value = false));
 
             AddUntilStep("hidetarget is hidden", () => !hideTarget.IsPresent);
             AddAssert("pause button is still visible", () => hudOverlay.HoldToQuit.IsPresent);
@@ -89,14 +113,14 @@ namespace osu.Game.Tests.Visual.Gameplay
             AddStep("set keycounter visible false", () =>
             {
                 config.Set<bool>(OsuSetting.KeyOverlay, false);
-                hudOverlay.KeyCounter.AlwaysVisible.Value = false;
+                hudOverlays.ForEach(h => h.KeyCounter.AlwaysVisible.Value = false);
             });
 
-            AddStep("set showhud false", () => hudOverlay.ShowHud.Value = false);
+            AddStep("set showhud false", () => hudOverlays.ForEach(h => h.ShowHud.Value = false));
             AddUntilStep("hidetarget is hidden", () => !hideTarget.IsPresent);
             AddAssert("key counters hidden", () => !keyCounterFlow.IsPresent);
 
-            AddStep("set showhud true", () => hudOverlay.ShowHud.Value = true);
+            AddStep("set showhud true", () => hudOverlays.ForEach(h => h.ShowHud.Value = true));
             AddUntilStep("hidetarget is visible", () => hideTarget.IsPresent);
             AddAssert("key counters still hidden", () => !keyCounterFlow.IsPresent);
 
@@ -107,13 +131,22 @@ namespace osu.Game.Tests.Visual.Gameplay
         {
             AddStep("create overlay", () =>
             {
-                Child = hudOverlay = new HUDOverlay(null, null, null, Array.Empty<Mod>());
+                SetContents(() =>
+                {
+                    hudOverlay = new HUDOverlay(null, null, null, Array.Empty<Mod>());
 
-                // Add any key just to display the key counter visually.
+                    // Add any key just to display the key counter visually.
-                hudOverlay.KeyCounter.Add(new KeyCounterKeyboard(Key.Space));
+                    hudOverlay.KeyCounter.Add(new KeyCounterKeyboard(Key.Space));
 
-                action?.Invoke(hudOverlay);
+                    hudOverlay.ComboCounter.Current.Value = 1;
+
+                    action?.Invoke(hudOverlay);
+
+                    return hudOverlay;
+                });
             });
         }
+
+        protected override Ruleset CreateRulesetForSkinProvider() => new OsuRuleset();
     }
 }

osu.Game.Tests/Visual/Gameplay/TestSceneHitErrorMeter.cs

@@ -22,8 +22,10 @@ namespace osu.Game.Tests.Visual.Gameplay
     {
         private BarHitErrorMeter barMeter;
         private BarHitErrorMeter barMeter2;
+        private BarHitErrorMeter barMeter3;
         private ColourHitErrorMeter colourMeter;
         private ColourHitErrorMeter colourMeter2;
+        private ColourHitErrorMeter colourMeter3;
         private HitWindows hitWindows;
 
         public TestSceneHitErrorMeter()
@@ -115,6 +117,13 @@ namespace osu.Game.Tests.Visual.Gameplay
                 Origin = Anchor.CentreLeft,
             });
 
+            Add(barMeter3 = new BarHitErrorMeter(hitWindows, true)
+            {
+                Anchor = Anchor.BottomCentre,
+                Origin = Anchor.CentreLeft,
+                Rotation = 270,
+            });
+
             Add(colourMeter = new ColourHitErrorMeter(hitWindows)
             {
                 Anchor = Anchor.CentreRight,
@@ -128,6 +137,14 @@ namespace osu.Game.Tests.Visual.Gameplay
                 Origin = Anchor.CentreLeft,
                 Margin = new MarginPadding { Left = 50 }
             });
+
+            Add(colourMeter3 = new ColourHitErrorMeter(hitWindows)
+            {
+                Anchor = Anchor.BottomCentre,
+                Origin = Anchor.CentreLeft,
+                Rotation = 270,
+                Margin = new MarginPadding { Left = 50 }
+            });
         }
 
         private void newJudgement(double offset = 0)
@@ -140,8 +157,10 @@ namespace osu.Game.Tests.Visual.Gameplay
 
             barMeter.OnNewJudgement(judgement);
             barMeter2.OnNewJudgement(judgement);
+            barMeter3.OnNewJudgement(judgement);
             colourMeter.OnNewJudgement(judgement);
             colourMeter2.OnNewJudgement(judgement);
+            colourMeter3.OnNewJudgement(judgement);
         }
     }
 }

osu.Game.Tests/Visual/Gameplay/TestSceneScoreCounter.cs

@@ -1,68 +0,0 @@
-// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
-// See the LICENCE file in the repository root for full licence text.
-
-using NUnit.Framework;
-using osu.Framework.Graphics;
-using osu.Game.Graphics.UserInterface;
-using osu.Game.Screens.Play.HUD;
-using osuTK;
-
-namespace osu.Game.Tests.Visual.Gameplay
-{
-    [TestFixture]
-    public class TestSceneScoreCounter : OsuTestScene
-    {
-        public TestSceneScoreCounter()
-        {
-            int numerator = 0, denominator = 0;
-
-            ScoreCounter score = new ScoreCounter(7)
-            {
-                Origin = Anchor.TopRight,
-                Anchor = Anchor.TopRight,
-                Margin = new MarginPadding(20),
-            };
-            Add(score);
-
-            ComboCounter comboCounter = new StandardComboCounter
-            {
-                Origin = Anchor.BottomLeft,
-                Anchor = Anchor.BottomLeft,
-                Margin = new MarginPadding(10),
-            };
-            Add(comboCounter);
-
-            PercentageCounter accuracyCounter = new PercentageCounter
-            {
-                Origin = Anchor.TopRight,
-                Anchor = Anchor.TopRight,
-                Position = new Vector2(-20, 60),
-            };
-            Add(accuracyCounter);
-
-            AddStep(@"Reset all", delegate
-            {
-                score.Current.Value = 0;
-                comboCounter.Current.Value = 0;
-                numerator = denominator = 0;
-                accuracyCounter.SetFraction(0, 0);
-            });
-
-            AddStep(@"Hit! :D", delegate
-            {
-                score.Current.Value += 300 + (ulong)(300.0 * (comboCounter.Current.Value > 0 ? comboCounter.Current.Value - 1 : 0) / 25.0);
-                comboCounter.Increment();
-                numerator++;
-                denominator++;
-                accuracyCounter.SetFraction(numerator, denominator);
-            });
-
-            AddStep(@"miss...", delegate
-            {
-                comboCounter.Current.Value = 0;
-                denominator++;
-                accuracyCounter.SetFraction(numerator, denominator);
-            });
-        }
-    }
-}

osu.Game.Tests/Visual/Gameplay/TestSceneSkinnableAccuracyCounter.cs

@@ -0,0 +1,49 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System.Collections.Generic;
+using System.Linq;
+using NUnit.Framework;
+using osu.Framework.Testing;
+using osu.Game.Rulesets;
+using osu.Game.Rulesets.Osu;
+using osu.Game.Screens.Play.HUD;
+
+namespace osu.Game.Tests.Visual.Gameplay
+{
+    public class TestSceneSkinnableAccuracyCounter : SkinnableTestScene
+    {
+        private IEnumerable<SkinnableAccuracyCounter> accuracyCounters => CreatedDrawables.OfType<SkinnableAccuracyCounter>();
+
+        protected override Ruleset CreateRulesetForSkinProvider() => new OsuRuleset();
+
+        [SetUpSteps]
+        public void SetUpSteps()
+        {
+            AddStep("Create combo counters", () => SetContents(() =>
+            {
+                var accuracyCounter = new SkinnableAccuracyCounter();
+
+                accuracyCounter.Current.Value = 1;
+
+                return accuracyCounter;
+            }));
+        }
+
+        [Test]
+        public void TestChangingAccuracy()
+        {
+            AddStep(@"Reset all", delegate
+            {
+                foreach (var s in accuracyCounters)
+                    s.Current.Value = 1;
+            });
+
+            AddStep(@"Hit! :D", delegate
+            {
+                foreach (var s in accuracyCounters)
+                    s.Current.Value -= 0.023f;
+            });
+        }
+    }
+}

osu.Game.Tests/Visual/Gameplay/TestSceneSkinnableHealthDisplay.cs

@@ -0,0 +1,61 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System.Collections.Generic;
+using System.Linq;
+using NUnit.Framework;
+using osu.Framework.Testing;
+using osu.Game.Rulesets;
+using osu.Game.Rulesets.Judgements;
+using osu.Game.Rulesets.Osu;
+using osu.Game.Rulesets.Osu.Judgements;
+using osu.Game.Screens.Play;
+
+namespace osu.Game.Tests.Visual.Gameplay
+{
+    public class TestSceneSkinnableHealthDisplay : SkinnableTestScene
+    {
+        private IEnumerable<SkinnableHealthDisplay> healthDisplays => CreatedDrawables.OfType<SkinnableHealthDisplay>();
+
+        protected override Ruleset CreateRulesetForSkinProvider() => new OsuRuleset();
+
+        [SetUpSteps]
+        public void SetUpSteps()
+        {
+            AddStep("Create health displays", () =>
+            {
+                SetContents(() => new SkinnableHealthDisplay());
+            });
+            AddStep(@"Reset all", delegate
+            {
+                foreach (var s in healthDisplays)
+                    s.Current.Value = 1;
+            });
+        }
+
+        [Test]
+        public void TestHealthDisplayIncrementing()
+        {
+            AddRepeatStep(@"decrease hp", delegate
+            {
+                foreach (var healthDisplay in healthDisplays)
+                    healthDisplay.Current.Value -= 0.08f;
+            }, 10);
+
+            AddRepeatStep(@"increase hp without flash", delegate
+            {
+                foreach (var healthDisplay in healthDisplays)
+                    healthDisplay.Current.Value += 0.1f;
+            }, 3);
+
+            AddRepeatStep(@"increase hp with flash", delegate
+            {
+                foreach (var healthDisplay in healthDisplays)
+                {
+                    healthDisplay.Current.Value += 0.1f;
+                    healthDisplay.Flash(new JudgementResult(null, new OsuJudgement()));
+                }
+            }, 3);
+        }
+    }
+}

osu.Game.Tests/Visual/Gameplay/TestSceneSkinnableScoreCounter.cs

@@ -0,0 +1,47 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System.Collections.Generic;
+using System.Linq;
+using NUnit.Framework;
+using osu.Framework.Testing;
+using osu.Game.Rulesets;
+using osu.Game.Rulesets.Osu;
+using osu.Game.Screens.Play.HUD;
+
+namespace osu.Game.Tests.Visual.Gameplay
+{
+    public class TestSceneSkinnableScoreCounter : SkinnableTestScene
+    {
+        private IEnumerable<SkinnableScoreCounter> scoreCounters => CreatedDrawables.OfType<SkinnableScoreCounter>();
+
+        protected override Ruleset CreateRulesetForSkinProvider() => new OsuRuleset();
+
+        [SetUpSteps]
+        public void SetUpSteps()
+        {
+            AddStep("Create combo counters", () => SetContents(() =>
+            {
+                var comboCounter = new SkinnableScoreCounter();
+                comboCounter.Current.Value = 1;
+                return comboCounter;
+            }));
+        }
+
+        [Test]
+        public void TestScoreCounterIncrementing()
+        {
+            AddStep(@"Reset all", delegate
+            {
+                foreach (var s in scoreCounters)
+                    s.Current.Value = 0;
+            });
+
+            AddStep(@"Hit! :D", delegate
+            {
+                foreach (var s in scoreCounters)
+                    s.Current.Value += 300;
+            });
+        }
+    }
+}

osu.Game.Tests/Visual/Gameplay/TestSceneSkinnableSound.cs

@@ -13,7 +13,6 @@ using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.OpenGL.Textures;
 using osu.Framework.Graphics.Textures;
 using osu.Framework.Testing;
-using osu.Framework.Timing;
 using osu.Game.Audio;
 using osu.Game.Screens.Play;
 using osu.Game.Skinning;
@@ -22,27 +21,24 @@ namespace osu.Game.Tests.Visual.Gameplay
 {
     public class TestSceneSkinnableSound : OsuTestScene
     {
-        [Cached(typeof(ISamplePlaybackDisabler))]
-        private GameplayClock gameplayClock = new GameplayClock(new FramedClock());
-
         private TestSkinSourceContainer skinSource;
         private PausableSkinnableSound skinnableSound;
 
         [SetUp]
-        public void SetUp() => Schedule(() =>
+        public void SetUpSteps()
         {
-            gameplayClock.IsPaused.Value = false;
+            AddStep("setup hierarchy", () =>
-
-            Children = new Drawable[]
             {
-                skinSource = new TestSkinSourceContainer
+                Children = new Drawable[]
                 {
-                    Clock = gameplayClock,
+                    skinSource = new TestSkinSourceContainer
-                    RelativeSizeAxes = Axes.Both,
+                    {
-                    Child = skinnableSound = new PausableSkinnableSound(new SampleInfo("normal-sliderslide"))
+                        RelativeSizeAxes = Axes.Both,
-                },
+                        Child = skinnableSound = new PausableSkinnableSound(new SampleInfo("normal-sliderslide"))
-            };
+                    },
-        });
+                };
+            });
+        }
 
         [Test]
         public void TestStoppedSoundDoesntResumeAfterPause()
@@ -62,8 +58,9 @@ namespace osu.Game.Tests.Visual.Gameplay
 
             AddUntilStep("wait for sample to stop playing", () => !sample.Playing);
 
-            AddStep("pause gameplay clock", () => gameplayClock.IsPaused.Value = true);
+            AddStep("disable sample playback", () => skinSource.SamplePlaybackDisabled.Value = true);
-            AddStep("resume gameplay clock", () => gameplayClock.IsPaused.Value = false);
+
+            AddStep("enable sample playback", () => skinSource.SamplePlaybackDisabled.Value = false);
 
             AddWaitStep("wait a bit", 5);
             AddAssert("sample not playing", () => !sample.Playing);
@@ -82,8 +79,11 @@ namespace osu.Game.Tests.Visual.Gameplay
 
             AddUntilStep("wait for sample to start playing", () => sample.Playing);
 
-            AddStep("pause gameplay clock", () => gameplayClock.IsPaused.Value = true);
+            AddStep("disable sample playback", () => skinSource.SamplePlaybackDisabled.Value = true);
             AddUntilStep("wait for sample to stop playing", () => !sample.Playing);
+
+            AddStep("enable sample playback", () => skinSource.SamplePlaybackDisabled.Value = false);
+            AddUntilStep("wait for sample to start playing", () => sample.Playing);
         }
 
         [Test]
@@ -98,10 +98,11 @@ namespace osu.Game.Tests.Visual.Gameplay
 
             AddAssert("sample playing", () => sample.Playing);
 
-            AddStep("pause gameplay clock", () => gameplayClock.IsPaused.Value = true);
+            AddStep("disable sample playback", () => skinSource.SamplePlaybackDisabled.Value = true);
-            AddUntilStep("wait for sample to stop playing", () => !sample.Playing);
 
-            AddStep("resume gameplay clock", () => gameplayClock.IsPaused.Value = false);
+            AddUntilStep("sample not playing", () => !sample.Playing);
+
+            AddStep("enable sample playback", () => skinSource.SamplePlaybackDisabled.Value = false);
 
             AddAssert("sample not playing", () => !sample.Playing);
             AddAssert("sample not playing", () => !sample.Playing);
@@ -120,7 +121,7 @@ namespace osu.Game.Tests.Visual.Gameplay
 
             AddAssert("sample playing", () => sample.Playing);
 
-            AddStep("pause gameplay clock", () => gameplayClock.IsPaused.Value = true);
+            AddStep("disable sample playback", () => skinSource.SamplePlaybackDisabled.Value = true);
             AddUntilStep("wait for sample to stop playing", () => !sample.Playing);
 
             AddStep("trigger skin change", () => skinSource.TriggerSourceChanged());
@@ -133,20 +134,25 @@ namespace osu.Game.Tests.Visual.Gameplay
             });
 
             AddAssert("new sample stopped", () => !sample.Playing);
-            AddStep("resume gameplay clock", () => gameplayClock.IsPaused.Value = false);
+            AddStep("enable sample playback", () => skinSource.SamplePlaybackDisabled.Value = false);
 
             AddWaitStep("wait a bit", 5);
             AddAssert("new sample not played", () => !sample.Playing);
         }
 
         [Cached(typeof(ISkinSource))]
-        private class TestSkinSourceContainer : Container, ISkinSource
+        [Cached(typeof(ISamplePlaybackDisabler))]
+        private class TestSkinSourceContainer : Container, ISkinSource, ISamplePlaybackDisabler
         {
             [Resolved]
             private ISkinSource source { get; set; }
 
             public event Action SourceChanged;
 
+            public Bindable<bool> SamplePlaybackDisabled { get; } = new Bindable<bool>();
+
+            IBindable<bool> ISamplePlaybackDisabler.SamplePlaybackDisabled => SamplePlaybackDisabled;
+
             public Drawable GetDrawableComponent(ISkinComponent component) => source?.GetDrawableComponent(component);
             public Texture GetTexture(string componentName, WrapMode wrapModeS, WrapMode wrapModeT) => source?.GetTexture(componentName, wrapModeS, wrapModeT);
             public SampleChannel GetSample(ISampleInfo sampleInfo) => source?.GetSample(sampleInfo);

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

@@ -401,7 +401,7 @@ namespace osu.Game.Tests.Visual.SongSelect
             AddStep("Sort by author", () => carousel.Filter(new FilterCriteria { Sort = SortMode.Author }, false));
             AddAssert("Check zzzzz is at bottom", () => carousel.BeatmapSets.Last().Metadata.AuthorString == "zzzzz");
             AddStep("Sort by artist", () => carousel.Filter(new FilterCriteria { Sort = SortMode.Artist }, false));
-            AddAssert($"Check #{set_count} is at bottom", () => carousel.BeatmapSets.Last().Metadata.Title.EndsWith($"#{set_count}!"));
+            AddAssert($"Check #{set_count} is at bottom", () => carousel.BeatmapSets.Last().Metadata.Title.EndsWith($"#{set_count}!", StringComparison.Ordinal));
         }
 
         [Test]

osu.Game.Tests/Visual/UserInterface/TestSceneModSettings.cs

@@ -9,6 +9,7 @@ using osu.Framework.Bindables;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Utils;
+using osu.Framework.Testing;
 using osu.Game.Beatmaps;
 using osu.Game.Configuration;
 using osu.Game.Graphics.UserInterface;
@@ -18,10 +19,11 @@ using osu.Game.Rulesets.Difficulty;
 using osu.Game.Rulesets.Mods;
 using osu.Game.Rulesets.Osu.Mods;
 using osu.Game.Rulesets.UI;
+using osuTK.Input;
 
 namespace osu.Game.Tests.Visual.UserInterface
 {
-    public class TestSceneModSettings : OsuTestScene
+    public class TestSceneModSettings : OsuManualInputManagerTestScene
     {
         private TestModSelectOverlay modSelect;
 
@@ -95,6 +97,41 @@ namespace osu.Game.Tests.Visual.UserInterface
             AddAssert("copy has original value", () => Precision.AlmostEquals(1.5, copy.SpeedChange.Value));
         }
 
+        [Test]
+        public void TestMultiModSettingsUnboundWhenCopied()
+        {
+            MultiMod original = null;
+            MultiMod copy = null;
+
+            AddStep("create mods", () =>
+            {
+                original = new MultiMod(new OsuModDoubleTime());
+                copy = (MultiMod)original.CreateCopy();
+            });
+
+            AddStep("change property", () => ((OsuModDoubleTime)original.Mods[0]).SpeedChange.Value = 2);
+
+            AddAssert("original has new value", () => Precision.AlmostEquals(2.0, ((OsuModDoubleTime)original.Mods[0]).SpeedChange.Value));
+            AddAssert("copy has original value", () => Precision.AlmostEquals(1.5, ((OsuModDoubleTime)copy.Mods[0]).SpeedChange.Value));
+        }
+
+        [Test]
+        public void TestCustomisationMenuNoClickthrough()
+        {
+            createModSelect();
+            openModSelect();
+
+            AddStep("change mod settings menu width to full screen", () => modSelect.SetModSettingsWidth(1.0f));
+            AddStep("select cm2", () => modSelect.SelectMod(testCustomisableAutoOpenMod));
+            AddAssert("Customisation opened", () => modSelect.ModSettingsContainer.Alpha == 1);
+            AddStep("hover over mod behind settings menu", () => InputManager.MoveMouseTo(modSelect.GetModButton(testCustomisableMod)));
+            AddAssert("Mod is not considered hovered over", () => !modSelect.GetModButton(testCustomisableMod).IsHovered);
+            AddStep("left click mod", () => InputManager.Click(MouseButton.Left));
+            AddAssert("only cm2 is active", () => SelectedMods.Value.Count == 1);
+            AddStep("right click mod", () => InputManager.Click(MouseButton.Right));
+            AddAssert("only cm2 is active", () => SelectedMods.Value.Count == 1);
+        }
+
         private void createModSelect()
         {
             AddStep("create mod select", () =>
@@ -121,9 +158,16 @@ namespace osu.Game.Tests.Visual.UserInterface
 
             public bool ButtonsLoaded => ModSectionsContainer.Children.All(c => c.ModIconsLoaded);
 
+            public ModButton GetModButton(Mod mod)
+            {
+                return ModSectionsContainer.ChildrenOfType<ModButton>().Single(b => b.Mods.Any(m => m.GetType() == mod.GetType()));
+            }
+
             public void SelectMod(Mod mod) =>
-                ModSectionsContainer.Children.Single(s => s.ModType == mod.Type)
+                GetModButton(mod).SelectNext(1);
-                                    .ButtonsContainer.OfType<ModButton>().Single(b => b.Mods.Any(m => m.GetType() == mod.GetType())).SelectNext(1);
+
+            public void SetModSettingsWidth(float newWidth) =>
+                ModSettingsContainer.Width = newWidth;
         }
 
         public class TestRulesetInfo : RulesetInfo

osu.Game.Tests/WaveformTestBeatmap.cs

@@ -1,6 +1,7 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+using System;
 using System.IO;
 using System.Linq;
 using osu.Framework.Audio;
@@ -59,7 +60,7 @@ namespace osu.Game.Tests
             get
             {
                 using (var reader = getZipReader())
-                    return reader.Filenames.First(f => f.EndsWith(".mp3"));
+                    return reader.Filenames.First(f => f.EndsWith(".mp3", StringComparison.Ordinal));
             }
         }
 
@@ -73,7 +74,7 @@ namespace osu.Game.Tests
             protected override Beatmap CreateBeatmap()
             {
                 using (var reader = getZipReader())
-                using (var beatmapStream = reader.GetStream(reader.Filenames.First(f => f.EndsWith(".osu"))))
+                using (var beatmapStream = reader.GetStream(reader.Filenames.First(f => f.EndsWith(".osu", StringComparison.Ordinal))))
                 using (var beatmapReader = new LineBufferedReader(beatmapStream))
                     return Decoder.GetDecoder<Beatmap>(beatmapReader).Decode(beatmapReader);
             }

osu.Game.Tournament/Screens/Drawings/DrawingsScreen.cs

@@ -234,7 +234,7 @@ namespace osu.Game.Tournament.Screens.Drawings
                             if (string.IsNullOrEmpty(line))
                                 continue;
 
-                            if (line.ToUpperInvariant().StartsWith("GROUP"))
+                            if (line.ToUpperInvariant().StartsWith("GROUP", StringComparison.Ordinal))
                                 continue;
 
                             // ReSharper disable once AccessToModifiedClosure

osu.Game/Beatmaps/BeatmapInfo.cs

@@ -98,7 +98,7 @@ namespace osu.Game.Beatmaps
         [JsonIgnore]
         public string StoredBookmarks
         {
-            get => string.Join(",", Bookmarks);
+            get => string.Join(',', Bookmarks);
             set
             {
                 if (string.IsNullOrEmpty(value))

osu.Game/Beatmaps/BeatmapManager.cs

@@ -19,6 +19,7 @@ using osu.Framework.Graphics.Textures;
 using osu.Framework.Lists;
 using osu.Framework.Logging;
 using osu.Framework.Platform;
+using osu.Framework.Testing;
 using osu.Game.Beatmaps.Formats;
 using osu.Game.Database;
 using osu.Game.IO;
@@ -36,6 +37,7 @@ namespace osu.Game.Beatmaps
     /// <summary>
     /// Handles the storage and retrieval of Beatmaps/WorkingBeatmaps.
     /// </summary>
+    [ExcludeFromDynamicCompile]
     public partial class BeatmapManager : DownloadableArchiveModelManager<BeatmapSetInfo, BeatmapSetFileInfo>, IDisposable
     {
         /// <summary>
@@ -389,7 +391,7 @@ namespace osu.Game.Beatmaps
         protected override BeatmapSetInfo CreateModel(ArchiveReader reader)
         {
             // let's make sure there are actually .osu files to import.
-            string mapName = reader.Filenames.FirstOrDefault(f => f.EndsWith(".osu"));
+            string mapName = reader.Filenames.FirstOrDefault(f => f.EndsWith(".osu", StringComparison.OrdinalIgnoreCase));
 
             if (string.IsNullOrEmpty(mapName))
             {
@@ -417,7 +419,7 @@ namespace osu.Game.Beatmaps
         {
             var beatmapInfos = new List<BeatmapInfo>();
 
-            foreach (var file in files.Where(f => f.Filename.EndsWith(".osu")))
+            foreach (var file in files.Where(f => f.Filename.EndsWith(".osu", StringComparison.OrdinalIgnoreCase)))
             {
                 using (var raw = Files.Store.GetStream(file.FileInfo.StoragePath))
                 using (var ms = new MemoryStream()) // we need a memory stream so we can seek

osu.Game/Beatmaps/BeatmapManager_BeatmapOnlineLookupQueue.cs

@@ -13,6 +13,7 @@ using osu.Framework.Development;
 using osu.Framework.IO.Network;
 using osu.Framework.Logging;
 using osu.Framework.Platform;
+using osu.Framework.Testing;
 using osu.Framework.Threading;
 using osu.Game.Online.API;
 using osu.Game.Online.API.Requests;
@@ -23,6 +24,7 @@ namespace osu.Game.Beatmaps
 {
     public partial class BeatmapManager
     {
+        [ExcludeFromDynamicCompile]
         private class BeatmapOnlineLookupQueue : IDisposable
         {
             private readonly IAPIProvider api;

osu.Game/Beatmaps/BeatmapManager_WorkingBeatmap.cs

@@ -8,6 +8,7 @@ using osu.Framework.Audio.Track;
 using osu.Framework.Graphics.Textures;
 using osu.Framework.IO.Stores;
 using osu.Framework.Logging;
+using osu.Framework.Testing;
 using osu.Game.Beatmaps.Formats;
 using osu.Game.IO;
 using osu.Game.Skinning;
@@ -17,6 +18,7 @@ namespace osu.Game.Beatmaps
 {
     public partial class BeatmapManager
     {
+        [ExcludeFromDynamicCompile]
         private class BeatmapManagerWorkingBeatmap : WorkingBeatmap
         {
             private readonly IResourceStore<byte[]> store;

osu.Game/Beatmaps/BeatmapSetInfo.cs

@@ -57,7 +57,7 @@ namespace osu.Game.Beatmaps
 
         public string Hash { get; set; }
 
-        public string StoryboardFile => Files?.Find(f => f.Filename.EndsWith(".osb"))?.Filename;
+        public string StoryboardFile => Files?.Find(f => f.Filename.EndsWith(".osb", StringComparison.OrdinalIgnoreCase))?.Filename;
 
         public List<BeatmapSetFileInfo> Files { get; set; }
 

osu.Game/Beatmaps/Formats/LegacyBeatmapDecoder.cs

@@ -307,12 +307,7 @@ namespace osu.Game.Beatmaps.Formats
                     double start = getOffsetTime(Parsing.ParseDouble(split[1]));
                     double end = Math.Max(start, getOffsetTime(Parsing.ParseDouble(split[2])));
 
-                    var breakEvent = new BreakPeriod(start, end);
+                    beatmap.Breaks.Add(new BreakPeriod(start, end));
-
-                    if (!breakEvent.HasEffect)
-                        return;
-
-                    beatmap.Breaks.Add(breakEvent);
                     break;
             }
         }

osu.Game/Beatmaps/Formats/LegacyDecoder.cs

@@ -92,7 +92,7 @@ namespace osu.Game.Beatmaps.Formats
         {
             var pair = SplitKeyVal(line);
 
-            bool isCombo = pair.Key.StartsWith(@"Combo");
+            bool isCombo = pair.Key.StartsWith(@"Combo", StringComparison.Ordinal);
 
             string[] split = pair.Value.Split(',');
 

osu.Game/Beatmaps/Timing/BreakPeriod.cs

@@ -28,7 +28,7 @@ namespace osu.Game.Beatmaps.Timing
         public double Duration => EndTime - StartTime;
 
         /// <summary>
-        /// Whether the break has any effect. Breaks that are too short are culled before they are added to the beatmap.
+        /// Whether the break has any effect.
         /// </summary>
         public bool HasEffect => Duration >= MIN_BREAK_DURATION;
 

osu.Game/Configuration/ScoreMeterType.cs

@@ -16,7 +16,10 @@ namespace osu.Game.Configuration
         [Description("Hit Error (right)")]
         HitErrorRight,
 
-        [Description("Hit Error (both)")]
+        [Description("Hit Error (bottom)")]
+        HitErrorBottom,
+
+        [Description("Hit Error (left+right)")]
         HitErrorBoth,
 
         [Description("Colour (left)")]
@@ -25,7 +28,10 @@ namespace osu.Game.Configuration
         [Description("Colour (right)")]
         ColourRight,
 
-        [Description("Colour (both)")]
+        [Description("Colour (left+right)")]
         ColourBoth,
+
+        [Description("Colour (bottom)")]
+        ColourBottom,
     }
 }

osu.Game/Database/ArchiveModelManager.cs

@@ -279,7 +279,7 @@ namespace osu.Game.Database
             // for now, concatenate all .osu files in the set to create a unique hash.
             MemoryStream hashable = new MemoryStream();
 
-            foreach (TFileModel file in item.Files.Where(f => HashableFileTypes.Any(f.Filename.EndsWith)).OrderBy(f => f.Filename))
+            foreach (TFileModel file in item.Files.Where(f => HashableFileTypes.Any(ext => f.Filename.EndsWith(ext, StringComparison.OrdinalIgnoreCase))).OrderBy(f => f.Filename))
             {
                 using (Stream s = Files.Store.GetStream(file.FileInfo.StoragePath))
                     s.CopyTo(hashable);
@@ -593,7 +593,7 @@ namespace osu.Game.Database
             var fileInfos = new List<TFileModel>();
 
             string prefix = reader.Filenames.GetCommonPrefix();
-            if (!(prefix.EndsWith("/") || prefix.EndsWith("\\")))
+            if (!(prefix.EndsWith('/') || prefix.EndsWith('\\')))
                 prefix = string.Empty;
 
             // import files to manager

osu.Game/Graphics/UserInterface/PercentageCounter.cs

@@ -2,7 +2,6 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System;
-using osu.Framework.Allocation;
 using osu.Framework.Graphics;
 using osu.Game.Graphics.Sprites;
 using osu.Game.Utils;
@@ -28,9 +27,6 @@ namespace osu.Game.Graphics.UserInterface
             Current.Value = DisplayedCount = 1.0f;
         }
 
-        [BackgroundDependencyLoader]
-        private void load(OsuColour colours) => Colour = colours.BlueLighter;
-
         protected override string FormatCount(double count) => count.FormatAccuracy();
 
         protected override double GetProportionalDuration(double currentValue, double newValue)

osu.Game/Graphics/UserInterface/ScoreCounter.cs

@@ -1,18 +1,21 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
-using osu.Framework.Allocation;
 using osu.Framework.Graphics;
 using osu.Game.Graphics.Sprites;
+using osu.Game.Screens.Play.HUD;
 
 namespace osu.Game.Graphics.UserInterface
 {
-    public class ScoreCounter : RollingCounter<double>
+    public abstract class ScoreCounter : RollingCounter<double>, IScoreCounter
     {
         protected override double RollingDuration => 1000;
         protected override Easing RollingEasing => Easing.Out;
 
-        public bool UseCommaSeparator;
+        /// <summary>
+        /// Whether comma separators should be displayed.
+        /// </summary>
+        public bool UseCommaSeparator { get; }
 
         /// <summary>
         /// How many leading zeroes the counter has.
@@ -23,14 +26,13 @@ namespace osu.Game.Graphics.UserInterface
         /// Displays score.
         /// </summary>
         /// <param name="leading">How many leading zeroes the counter will have.</param>
-        public ScoreCounter(uint leading = 0)
+        /// <param name="useCommaSeparator">Whether comma separators should be displayed.</param>
+        protected ScoreCounter(uint leading = 0, bool useCommaSeparator = false)
         {
+            UseCommaSeparator = useCommaSeparator;
             LeadingZeroes = leading;
         }
 
-        [BackgroundDependencyLoader]
-        private void load(OsuColour colours) => Colour = colours.BlueLighter;
-
         protected override double GetProportionalDuration(double currentValue, double newValue)
         {
             return currentValue > newValue ? currentValue - newValue : newValue - currentValue;

osu.Game/Online/Chat/ChannelManager.cs

@@ -196,7 +196,7 @@ namespace osu.Game.Online.Chat
             if (target == null)
                 return;
 
-            var parameters = text.Split(new[] { ' ' }, 2);
+            var parameters = text.Split(' ', 2);
             string command = parameters[0];
             string content = parameters.Length == 2 ? parameters[1] : string.Empty;
 

osu.Game/Online/Chat/MessageFormatter.cs

@@ -111,7 +111,7 @@ namespace osu.Game.Online.Chat
 
         public static LinkDetails GetLinkDetails(string url)
         {
-            var args = url.Split(new[] { '/' }, StringSplitOptions.RemoveEmptyEntries);
+            var args = url.Split('/', StringSplitOptions.RemoveEmptyEntries);
             args[0] = args[0].TrimEnd(':');
 
             switch (args[0])

osu.Game/OsuGame.cs

@@ -181,7 +181,7 @@ namespace osu.Game
 
             if (args?.Length > 0)
             {
-                var paths = args.Where(a => !a.StartsWith(@"-")).ToArray();
+                var paths = args.Where(a => !a.StartsWith('-')).ToArray();
                 if (paths.Length > 0)
                     Task.Run(() => Import(paths));
             }
@@ -289,7 +289,7 @@ namespace osu.Game
 
         public void OpenUrlExternally(string url) => waitForReady(() => externalLinkOpener, _ =>
         {
-            if (url.StartsWith("/"))
+            if (url.StartsWith('/'))
                 url = $"{API.Endpoint}{url}";
 
             externalLinkOpener.OpenUrlExternally(url);

osu.Game/Overlays/Mods/ModSelectOverlay.cs

@@ -13,7 +13,6 @@ using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Shapes;
 using osu.Framework.Input.Events;
-using osu.Game.Configuration;
 using osu.Game.Graphics;
 using osu.Game.Graphics.Backgrounds;
 using osu.Game.Graphics.Containers;
@@ -45,9 +44,7 @@ namespace osu.Game.Overlays.Mods
 
         protected readonly FillFlowContainer<ModSection> ModSectionsContainer;
 
-        protected readonly FillFlowContainer<ModControlSection> ModSettingsContent;
+        protected readonly ModSettingsContainer ModSettingsContainer;
-
-        protected readonly Container ModSettingsContainer;
 
         public readonly Bindable<IReadOnlyList<Mod>> SelectedMods = new Bindable<IReadOnlyList<Mod>>(Array.Empty<Mod>());
 
@@ -284,7 +281,7 @@ namespace osu.Game.Overlays.Mods
                         },
                     },
                 },
-                ModSettingsContainer = new Container
+                ModSettingsContainer = new ModSettingsContainer
                 {
                     RelativeSizeAxes = Axes.Both,
                     Anchor = Anchor.BottomRight,
@@ -292,29 +289,11 @@ namespace osu.Game.Overlays.Mods
                     Width = 0.25f,
                     Alpha = 0,
                     X = -100,
-                    Children = new Drawable[]
+                    SelectedMods = { BindTarget = SelectedMods },
-                    {
-                        new Box
-                        {
-                            RelativeSizeAxes = Axes.Both,
-                            Colour = new Color4(0, 0, 0, 192)
-                        },
-                        new OsuScrollContainer
-                        {
-                            RelativeSizeAxes = Axes.Both,
-                            Child = ModSettingsContent = new FillFlowContainer<ModControlSection>
-                            {
-                                Anchor = Anchor.TopCentre,
-                                Origin = Anchor.TopCentre,
-                                RelativeSizeAxes = Axes.X,
-                                AutoSizeAxes = Axes.Y,
-                                Spacing = new Vector2(0f, 10f),
-                                Padding = new MarginPadding(20),
-                            }
-                        }
-                    }
                 }
             };
+
+            ((IBindable<bool>)CustomiseButton.Enabled).BindTo(ModSettingsContainer.HasSettingsForSelection);
         }
 
         [BackgroundDependencyLoader(true)]
@@ -423,8 +402,6 @@ namespace osu.Game.Overlays.Mods
                 section.SelectTypes(mods.NewValue.Select(m => m.GetType()).ToList());
 
             updateMods();
-
-            updateModSettings(mods);
         }
 
         private void updateMods()
@@ -445,25 +422,6 @@ namespace osu.Game.Overlays.Mods
                 MultiplierLabel.FadeColour(Color4.White, 200);
         }
 
-        private void updateModSettings(ValueChangedEvent<IReadOnlyList<Mod>> selectedMods)
-        {
-            ModSettingsContent.Clear();
-
-            foreach (var mod in selectedMods.NewValue)
-            {
-                var settings = mod.CreateSettingsControls().ToList();
-                if (settings.Count > 0)
-                    ModSettingsContent.Add(new ModControlSection(mod, settings));
-            }
-
-            bool hasSettings = ModSettingsContent.Count > 0;
-
-            CustomiseButton.Enabled.Value = hasSettings;
-
-            if (!hasSettings)
-                ModSettingsContainer.Hide();
-        }
-
         private void modButtonPressed(Mod selectedMod)
         {
             if (selectedMod != null)

osu.Game/Overlays/Mods/ModSettingsContainer.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.
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+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.Configuration;
+using osu.Game.Graphics.Containers;
+using osu.Game.Rulesets.Mods;
+using osuTK;
+using osuTK.Graphics;
+
+namespace osu.Game.Overlays.Mods
+{
+    public class ModSettingsContainer : Container
+    {
+        public readonly IBindable<IReadOnlyList<Mod>> SelectedMods = new Bindable<IReadOnlyList<Mod>>(Array.Empty<Mod>());
+
+        public IBindable<bool> HasSettingsForSelection => hasSettingsForSelection;
+
+        private readonly Bindable<bool> hasSettingsForSelection = new Bindable<bool>();
+
+        private readonly FillFlowContainer<ModControlSection> modSettingsContent;
+
+        public ModSettingsContainer()
+        {
+            Children = new Drawable[]
+            {
+                new Box
+                {
+                    RelativeSizeAxes = Axes.Both,
+                    Colour = new Color4(0, 0, 0, 192)
+                },
+                new OsuScrollContainer
+                {
+                    RelativeSizeAxes = Axes.Both,
+                    Child = modSettingsContent = new FillFlowContainer<ModControlSection>
+                    {
+                        Anchor = Anchor.TopCentre,
+                        Origin = Anchor.TopCentre,
+                        RelativeSizeAxes = Axes.X,
+                        AutoSizeAxes = Axes.Y,
+                        Spacing = new Vector2(0f, 10f),
+                        Padding = new MarginPadding(20),
+                    }
+                }
+            };
+        }
+
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            SelectedMods.BindValueChanged(modsChanged, true);
+        }
+
+        private void modsChanged(ValueChangedEvent<IReadOnlyList<Mod>> mods)
+        {
+            modSettingsContent.Clear();
+
+            foreach (var mod in mods.NewValue)
+            {
+                var settings = mod.CreateSettingsControls().ToList();
+                if (settings.Count > 0)
+                    modSettingsContent.Add(new ModControlSection(mod, settings));
+            }
+
+            bool hasSettings = modSettingsContent.Count > 0;
+
+            if (!hasSettings)
+                Hide();
+
+            hasSettingsForSelection.Value = hasSettings;
+        }
+
+        protected override bool OnMouseDown(MouseDownEvent e) => true;
+        protected override bool OnHover(HoverEvent e) => true;
+    }
+}

osu.Game/Overlays/Profile/Header/BottomHeaderContainer.cs

@@ -135,7 +135,6 @@ namespace osu.Game.Overlays.Profile.Header
                 anyInfoAdded |= tryAddInfo(FontAwesome.Brands.Twitter, "@" + user.Twitter, $@"https://twitter.com/{user.Twitter}");
             anyInfoAdded |= tryAddInfo(FontAwesome.Brands.Discord, user.Discord);
             anyInfoAdded |= tryAddInfo(FontAwesome.Brands.Skype, user.Skype, @"skype:" + user.Skype + @"?chat");
-            anyInfoAdded |= tryAddInfo(FontAwesome.Brands.Lastfm, user.Lastfm, $@"https://last.fm/users/{user.Lastfm}");
             anyInfoAdded |= tryAddInfo(FontAwesome.Solid.Link, websiteWithoutProtocol, user.Website);
 
             // If no information was added to the bottomLinkContainer, hide it to avoid unwanted padding
@@ -149,7 +148,7 @@ namespace osu.Game.Overlays.Profile.Header
             if (string.IsNullOrEmpty(content)) return false;
 
             // newlines could be contained in API returned user content.
-            content = content.Replace("\n", " ");
+            content = content.Replace('\n', ' ');
 
             bottomLinkContainer.AddIcon(icon, text =>
             {

osu.Game/Rulesets/Difficulty/DifficultyCalculator.cs

@@ -69,7 +69,7 @@ namespace osu.Game.Rulesets.Difficulty
             if (!beatmap.HitObjects.Any())
                 return CreateDifficultyAttributes(beatmap, mods, skills, clockRate);
 
-            var difficultyHitObjects = CreateDifficultyHitObjects(beatmap, clockRate).OrderBy(h => h.BaseObject.StartTime).ToList();
+            var difficultyHitObjects = SortObjects(CreateDifficultyHitObjects(beatmap, clockRate)).ToList();
 
             double sectionLength = SectionLength * clockRate;
 
@@ -100,15 +100,24 @@ namespace osu.Game.Rulesets.Difficulty
             return CreateDifficultyAttributes(beatmap, mods, skills, clockRate);
         }
 
+        /// <summary>
+        /// Sorts a given set of <see cref="DifficultyHitObject"/>s.
+        /// </summary>
+        /// <param name="input">The <see cref="DifficultyHitObject"/>s to sort.</param>
+        /// <returns>The sorted <see cref="DifficultyHitObject"/>s.</returns>
+        protected virtual IEnumerable<DifficultyHitObject> SortObjects(IEnumerable<DifficultyHitObject> input)
+            => input.OrderBy(h => h.BaseObject.StartTime);
+
         /// <summary>
         /// Creates all <see cref="Mod"/> combinations which adjust the <see cref="Beatmap"/> difficulty.
         /// </summary>
         public Mod[] CreateDifficultyAdjustmentModCombinations()
         {
-            return createDifficultyAdjustmentModCombinations(Array.Empty<Mod>(), DifficultyAdjustmentMods).ToArray();
+            return createDifficultyAdjustmentModCombinations(DifficultyAdjustmentMods, Array.Empty<Mod>()).ToArray();
 
-            IEnumerable<Mod> createDifficultyAdjustmentModCombinations(IEnumerable<Mod> currentSet, Mod[] adjustmentSet, int currentSetCount = 0, int adjustmentSetStart = 0)
+            static IEnumerable<Mod> createDifficultyAdjustmentModCombinations(ReadOnlyMemory<Mod> remainingMods, IEnumerable<Mod> currentSet, int currentSetCount = 0)
             {
+                // Return the current set.
                 switch (currentSetCount)
                 {
                     case 0:
@@ -128,18 +137,43 @@ namespace osu.Game.Rulesets.Difficulty
                         break;
                 }
 
-                // Apply mods in the adjustment set recursively. Using the entire adjustment set would result in duplicate multi-mod mod
+                // Apply the rest of the remaining mods recursively.
-                // combinations in further recursions, so a moving subset is used to eliminate this effect
+                for (int i = 0; i < remainingMods.Length; i++)
-                for (int i = adjustmentSetStart; i < adjustmentSet.Length; i++)
                 {
-                    var adjustmentMod = adjustmentSet[i];
+                    var (nextSet, nextCount) = flatten(remainingMods.Span[i]);
-                    if (currentSet.Any(c => c.IncompatibleMods.Any(m => m.IsInstanceOfType(adjustmentMod))))
+
+                    // Check if any mods in the next set are incompatible with any of the current set.
+                    if (currentSet.SelectMany(m => m.IncompatibleMods).Any(c => nextSet.Any(c.IsInstanceOfType)))
                         continue;
 
-                    foreach (var combo in createDifficultyAdjustmentModCombinations(currentSet.Append(adjustmentMod), adjustmentSet, currentSetCount + 1, i + 1))
+                    // Check if any mods in the next set are the same type as the current set. Mods of the exact same type are not incompatible with themselves.
+                    if (currentSet.Any(c => nextSet.Any(n => c.GetType() == n.GetType())))
+                        continue;
+
+                    // If all's good, attach the next set to the current set and recurse further.
+                    foreach (var combo in createDifficultyAdjustmentModCombinations(remainingMods.Slice(i + 1), currentSet.Concat(nextSet), currentSetCount + nextCount))
                         yield return combo;
                 }
             }
+
+            // Flattens a mod hierarchy (through MultiMod) as an IEnumerable<Mod>
+            static (IEnumerable<Mod> set, int count) flatten(Mod mod)
+            {
+                if (!(mod is MultiMod multi))
+                    return (mod.Yield(), 1);
+
+                IEnumerable<Mod> set = Enumerable.Empty<Mod>();
+                int count = 0;
+
+                foreach (var nested in multi.Mods)
+                {
+                    var (nestedSet, nestedCount) = flatten(nested);
+                    set = set.Concat(nestedSet);
+                    count += nestedCount;
+                }
+
+                return (set, count);
+            }
         }
 
         /// <summary>

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

@@ -41,7 +41,11 @@ namespace osu.Game.Rulesets.Difficulty.Skills
         /// </summary>
         protected readonly LimitedCapacityStack<DifficultyHitObject> Previous = new LimitedCapacityStack<DifficultyHitObject>(2); // Contained objects not used yet
 
-        private double currentStrain = 1; // We keep track of the strain level at all times throughout the beatmap.
+        /// <summary>
+        /// The current strain level.
+        /// </summary>
+        protected double CurrentStrain { get; private set; } = 1;
+
         private double currentSectionPeak = 1; // We also keep track of the peak strain level in the current section.
 
         private readonly List<double> strainPeaks = new List<double>();
@@ -51,10 +55,10 @@ namespace osu.Game.Rulesets.Difficulty.Skills
         /// </summary>
         public void Process(DifficultyHitObject current)
         {
-            currentStrain *= strainDecay(current.DeltaTime);
+            CurrentStrain *= strainDecay(current.DeltaTime);
-            currentStrain += StrainValueOf(current) * SkillMultiplier;
+            CurrentStrain += StrainValueOf(current) * SkillMultiplier;
 
-            currentSectionPeak = Math.Max(currentStrain, currentSectionPeak);
+            currentSectionPeak = Math.Max(CurrentStrain, currentSectionPeak);
 
             Previous.Push(current);
         }
@@ -71,15 +75,22 @@ namespace osu.Game.Rulesets.Difficulty.Skills
         /// <summary>
         /// Sets the initial strain level for a new section.
         /// </summary>
-        /// <param name="offset">The beginning of the new section in milliseconds.</param>
+        /// <param name="time">The beginning of the new section in milliseconds.</param>
-        public void StartNewSectionFrom(double offset)
+        public void StartNewSectionFrom(double time)
         {
             // The maximum strain of the new section is not zero by default, strain decays as usual regardless of section boundaries.
             // This means we need to capture the strain level at the beginning of the new section, and use that as the initial peak level.
             if (Previous.Count > 0)
-                currentSectionPeak = currentStrain * strainDecay(offset - Previous[0].BaseObject.StartTime);
+                currentSectionPeak = GetPeakStrain(time);
         }
 
+        /// <summary>
+        /// Retrieves the peak strain at a point in time.
+        /// </summary>
+        /// <param name="time">The time to retrieve the peak strain at.</param>
+        /// <returns>The peak strain.</returns>
+        protected virtual double GetPeakStrain(double time) => CurrentStrain * strainDecay(time - Previous[0].BaseObject.StartTime);
+
         /// <summary>
         /// Returns the calculated difficulty value representing all processed <see cref="DifficultyHitObject"/>s.
         /// </summary>

osu.Game/Rulesets/Mods/ModFlashlight.cs

@@ -107,6 +107,9 @@ namespace osu.Game.Rulesets.Mods
                 {
                     foreach (var breakPeriod in Breaks)
                     {
+                        if (!breakPeriod.HasEffect)
+                            continue;
+
                         if (breakPeriod.Duration < FLASHLIGHT_FADE_DURATION * 2) continue;
 
                         this.Delay(breakPeriod.StartTime + FLASHLIGHT_FADE_DURATION).FadeOutFromOne(FLASHLIGHT_FADE_DURATION);

osu.Game/Rulesets/Mods/MultiMod.cs

@@ -6,7 +6,7 @@ using System.Linq;
 
 namespace osu.Game.Rulesets.Mods
 {
-    public class MultiMod : Mod
+    public sealed class MultiMod : Mod
     {
         public override string Name => string.Empty;
         public override string Acronym => string.Empty;
@@ -20,6 +20,8 @@ namespace osu.Game.Rulesets.Mods
             Mods = mods;
         }
 
+        public override Mod CreateCopy() => new MultiMod(Mods.Select(m => m.CreateCopy()).ToArray());
+
         public override Type[] IncompatibleMods => Mods.SelectMany(m => m.IncompatibleMods).ToArray();
     }
 }

osu.Game/Rulesets/Objects/Legacy/ConvertHitObjectParser.cs

@@ -159,7 +159,7 @@ namespace osu.Game.Rulesets.Objects.Legacy
                 {
                     string[] ss = split[5].Split(':');
                     endTime = Math.Max(startTime, Parsing.ParseDouble(ss[0]));
-                    readCustomSampleBanks(string.Join(":", ss.Skip(1)), bankInfo);
+                    readCustomSampleBanks(string.Join(':', ss.Skip(1)), bankInfo);
                 }
 
                 result = CreateHold(pos, combo, comboOffset, endTime + Offset - startTime);

osu.Game/Rulesets/RulesetStore.cs

@@ -96,11 +96,13 @@ namespace osu.Game.Rulesets
                 context.SaveChanges();
 
                 // add any other modes
+                var existingRulesets = context.RulesetInfo.ToList();
+
                 foreach (var r in instances.Where(r => !(r is ILegacyRuleset)))
                 {
                     // todo: StartsWith can be changed to Equals on 2020-11-08
                     // This is to give users enough time to have their database use new abbreviated info).
-                    if (context.RulesetInfo.FirstOrDefault(ri => ri.InstantiationInfo.StartsWith(r.RulesetInfo.InstantiationInfo)) == null)
+                    if (existingRulesets.FirstOrDefault(ri => ri.InstantiationInfo.StartsWith(r.RulesetInfo.InstantiationInfo, StringComparison.Ordinal)) == null)
                         context.RulesetInfo.Add(r.RulesetInfo);
                 }
 

osu.Game/Rulesets/UI/FrameStabilityContainer.cs

@@ -18,8 +18,11 @@ namespace osu.Game.Rulesets.UI
     /// A container which consumes a parent gameplay clock and standardises frame counts for children.
     /// Will ensure a minimum of 50 frames per clock second is maintained, regardless of any system lag or seeks.
     /// </summary>
-    public class FrameStabilityContainer : Container, IHasReplayHandler
+    [Cached(typeof(ISamplePlaybackDisabler))]
+    public class FrameStabilityContainer : Container, IHasReplayHandler, ISamplePlaybackDisabler
     {
+        private readonly Bindable<bool> samplePlaybackDisabled = new Bindable<bool>();
+
         private readonly double gameplayStartTime;
 
         /// <summary>
@@ -35,7 +38,6 @@ namespace osu.Game.Rulesets.UI
         public GameplayClock GameplayClock => stabilityGameplayClock;
 
         [Cached(typeof(GameplayClock))]
-        [Cached(typeof(ISamplePlaybackDisabler))]
         private readonly StabilityGameplayClock stabilityGameplayClock;
 
         public FrameStabilityContainer(double gameplayStartTime = double.MinValue)
@@ -102,6 +104,8 @@ namespace osu.Game.Rulesets.UI
             requireMoreUpdateLoops = true;
             validState = !GameplayClock.IsPaused.Value;
 
+            samplePlaybackDisabled.Value = stabilityGameplayClock.ShouldDisableSamplePlayback;
+
             int loops = 0;
 
             while (validState && requireMoreUpdateLoops && loops++ < MaxCatchUpFrames)
@@ -224,6 +228,8 @@ namespace osu.Game.Rulesets.UI
 
         public ReplayInputHandler ReplayInputHandler { get; set; }
 
+        IBindable<bool> ISamplePlaybackDisabler.SamplePlaybackDisabled => samplePlaybackDisabled;
+
         private class StabilityGameplayClock : GameplayClock
         {
             public GameplayClock ParentGameplayClock;
@@ -237,7 +243,7 @@ namespace osu.Game.Rulesets.UI
             {
             }
 
-            protected override bool ShouldDisableSamplePlayback =>
+            public override bool ShouldDisableSamplePlayback =>
                 // handle the case where playback is catching up to real-time.
                 base.ShouldDisableSamplePlayback
                 || ParentSampleDisabler?.SamplePlaybackDisabled.Value == true

osu.Game/Scoring/ScoreManager.cs

@@ -57,7 +57,7 @@ namespace osu.Game.Scoring
             if (archive == null)
                 return null;
 
-            using (var stream = archive.GetStream(archive.Filenames.First(f => f.EndsWith(".osr"))))
+            using (var stream = archive.GetStream(archive.Filenames.First(f => f.EndsWith(".osr", StringComparison.OrdinalIgnoreCase))))
             {
                 try
                 {

osu.Game/Screens/Edit/Compose/Components/ComposeBlueprintContainer.cs

@@ -79,9 +79,7 @@ namespace osu.Game.Screens.Edit.Compose.Components
 
         private void updatePlacementNewCombo()
         {
-            if (currentPlacement == null) return;
+            if (currentPlacement?.HitObject is IHasComboInformation c)
-
-            if (currentPlacement.HitObject is IHasComboInformation c)
                 c.NewCombo = NewCombo.Value == TernaryState.True;
         }
 

osu.Game/Screens/Edit/Editor.cs

@@ -597,10 +597,20 @@ namespace osu.Game.Screens.Edit
         {
             double amount = e.ShiftPressed ? 4 : 1;
 
+            bool trackPlaying = clock.IsRunning;
+
+            if (trackPlaying)
+            {
+                // generally users are not looking to perform tiny seeks when the track is playing,
+                // so seeks should always be by one full beat, bypassing the beatDivisor.
+                // this multiplication undoes the division that will be applied in the underlying seek operation.
+                amount *= beatDivisor.Value;
+            }
+
             if (direction < 1)
-                clock.SeekBackward(!clock.IsRunning, amount);
+                clock.SeekBackward(!trackPlaying, amount);
             else
-                clock.SeekForward(!clock.IsRunning, amount);
+                clock.SeekForward(!trackPlaying, amount);
         }
 
         private void exportBeatmap()

osu.Game/Screens/Play/GameplayClock.cs

@@ -17,7 +17,7 @@ namespace osu.Game.Screens.Play
     /// <see cref="IFrameBasedClock"/>, as this should only be done once to ensure accuracy.
     /// </remarks>
     /// </summary>
-    public class GameplayClock : IFrameBasedClock, ISamplePlaybackDisabler
+    public class GameplayClock : IFrameBasedClock
     {
         private readonly IFrameBasedClock underlyingClock;
 
@@ -28,8 +28,6 @@ namespace osu.Game.Screens.Play
         /// </summary>
         public virtual IEnumerable<Bindable<double>> NonGameplayAdjustments => Enumerable.Empty<Bindable<double>>();
 
-        private readonly Bindable<bool> samplePlaybackDisabled = new Bindable<bool>();
-
         public GameplayClock(IFrameBasedClock underlyingClock)
         {
             this.underlyingClock = underlyingClock;
@@ -66,13 +64,11 @@ namespace osu.Game.Screens.Play
         /// <summary>
         /// Whether nested samples supporting the <see cref="ISamplePlaybackDisabler"/> interface should be paused.
         /// </summary>
-        protected virtual bool ShouldDisableSamplePlayback => IsPaused.Value;
+        public virtual bool ShouldDisableSamplePlayback => IsPaused.Value;
 
         public void ProcessFrame()
         {
             // intentionally not updating the underlying clock (handled externally).
-
-            samplePlaybackDisabled.Value = ShouldDisableSamplePlayback;
         }
 
         public double ElapsedFrameTime => underlyingClock.ElapsedFrameTime;
@@ -82,7 +78,5 @@ namespace osu.Game.Screens.Play
         public FrameTimeInfo TimeInfo => underlyingClock.TimeInfo;
 
         public IClock Source => underlyingClock;
-
-        IBindable<bool> ISamplePlaybackDisabler.SamplePlaybackDisabled => samplePlaybackDisabled;
     }
 }

osu.Game/Screens/Play/GameplayClockContainer.cs

@@ -54,7 +54,6 @@ namespace osu.Game.Screens.Play
         public GameplayClock GameplayClock => localGameplayClock;
 
         [Cached(typeof(GameplayClock))]
-        [Cached(typeof(ISamplePlaybackDisabler))]
         private readonly LocalGameplayClock localGameplayClock;
 
         private Bindable<double> userAudioOffset;

osu.Game/Screens/Play/HUD/ComboCounter.cs

@@ -1,200 +0,0 @@
-// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
-// See the LICENCE file in the repository root for full licence text.
-
-using osu.Framework.Bindables;
-using osu.Framework.Graphics;
-using osu.Framework.Graphics.Containers;
-using osu.Framework.Graphics.Sprites;
-using osu.Game.Graphics.Sprites;
-
-namespace osu.Game.Screens.Play.HUD
-{
-    public abstract class ComboCounter : Container
-    {
-        public BindableInt Current = new BindableInt
-        {
-            MinValue = 0,
-        };
-
-        public bool IsRolling { get; protected set; }
-
-        protected SpriteText PopOutCount;
-
-        protected virtual double PopOutDuration => 150;
-        protected virtual float PopOutScale => 2.0f;
-        protected virtual Easing PopOutEasing => Easing.None;
-        protected virtual float PopOutInitialAlpha => 0.75f;
-
-        protected virtual double FadeOutDuration => 100;
-
-        /// <summary>
-        /// Duration in milliseconds for the counter roll-up animation for each element.
-        /// </summary>
-        protected virtual double RollingDuration => 20;
-
-        /// <summary>
-        /// Easing for the counter rollover animation.
-        /// </summary>
-        protected Easing RollingEasing => Easing.None;
-
-        protected SpriteText DisplayedCountSpriteText;
-
-        private int previousValue;
-
-        /// <summary>
-        /// Base of all combo counters.
-        /// </summary>
-        protected ComboCounter()
-        {
-            AutoSizeAxes = Axes.Both;
-
-            Children = new Drawable[]
-            {
-                DisplayedCountSpriteText = new OsuSpriteText
-                {
-                    Alpha = 0,
-                },
-                PopOutCount = new OsuSpriteText
-                {
-                    Alpha = 0,
-                    Margin = new MarginPadding(0.05f),
-                }
-            };
-
-            TextSize = 80;
-
-            Current.ValueChanged += combo => updateCount(combo.NewValue == 0);
-        }
-
-        protected override void LoadComplete()
-        {
-            base.LoadComplete();
-
-            DisplayedCountSpriteText.Text = FormatCount(Current.Value);
-            DisplayedCountSpriteText.Anchor = Anchor;
-            DisplayedCountSpriteText.Origin = Origin;
-
-            StopRolling();
-        }
-
-        private int displayedCount;
-
-        /// <summary>
-        /// Value shown at the current moment.
-        /// </summary>
-        public virtual int DisplayedCount
-        {
-            get => displayedCount;
-            protected set
-            {
-                if (displayedCount.Equals(value))
-                    return;
-
-                updateDisplayedCount(displayedCount, value, IsRolling);
-            }
-        }
-
-        private float textSize;
-
-        public float TextSize
-        {
-            get => textSize;
-            set
-            {
-                textSize = value;
-
-                DisplayedCountSpriteText.Font = DisplayedCountSpriteText.Font.With(size: TextSize);
-                PopOutCount.Font = PopOutCount.Font.With(size: TextSize);
-            }
-        }
-
-        /// <summary>
-        /// Increments the combo by an amount.
-        /// </summary>
-        /// <param name="amount"></param>
-        public void Increment(int amount = 1)
-        {
-            Current.Value += amount;
-        }
-
-        /// <summary>
-        /// Stops rollover animation, forcing the displayed count to be the actual count.
-        /// </summary>
-        public void StopRolling()
-        {
-            updateCount(false);
-        }
-
-        protected virtual string FormatCount(int count)
-        {
-            return count.ToString();
-        }
-
-        protected virtual void OnCountRolling(int currentValue, int newValue)
-        {
-            transformRoll(currentValue, newValue);
-        }
-
-        protected virtual void OnCountIncrement(int currentValue, int newValue)
-        {
-            DisplayedCount = newValue;
-        }
-
-        protected virtual void OnCountChange(int currentValue, int newValue)
-        {
-            DisplayedCount = newValue;
-        }
-
-        private double getProportionalDuration(int currentValue, int newValue)
-        {
-            double difference = currentValue > newValue ? currentValue - newValue : newValue - currentValue;
-            return difference * RollingDuration;
-        }
-
-        private void updateDisplayedCount(int currentValue, int newValue, bool rolling)
-        {
-            displayedCount = newValue;
-            if (rolling)
-                OnDisplayedCountRolling(currentValue, newValue);
-            else if (currentValue + 1 == newValue)
-                OnDisplayedCountIncrement(newValue);
-            else
-                OnDisplayedCountChange(newValue);
-        }
-
-        private void updateCount(bool rolling)
-        {
-            int prev = previousValue;
-            previousValue = Current.Value;
-
-            if (!IsLoaded)
-                return;
-
-            if (!rolling)
-            {
-                FinishTransforms(false, nameof(DisplayedCount));
-                IsRolling = false;
-                DisplayedCount = prev;
-
-                if (prev + 1 == Current.Value)
-                    OnCountIncrement(prev, Current.Value);
-                else
-                    OnCountChange(prev, Current.Value);
-            }
-            else
-            {
-                OnCountRolling(displayedCount, Current.Value);
-                IsRolling = true;
-            }
-        }
-
-        private void transformRoll(int currentValue, int newValue)
-        {
-            this.TransformTo(nameof(DisplayedCount), newValue, getProportionalDuration(currentValue, newValue), RollingEasing);
-        }
-
-        protected abstract void OnDisplayedCountRolling(int currentValue, int newValue);
-        protected abstract void OnDisplayedCountIncrement(int newValue);
-        protected abstract void OnDisplayedCountChange(int newValue);
-    }
-}

osu.Game/Screens/Play/HUD/DefaultAccuracyCounter.cs

@@ -0,0 +1,43 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Framework.Allocation;
+using osu.Framework.Graphics;
+using osu.Game.Graphics;
+using osu.Game.Graphics.UserInterface;
+using osuTK;
+
+namespace osu.Game.Screens.Play.HUD
+{
+    public class DefaultAccuracyCounter : PercentageCounter, IAccuracyCounter
+    {
+        private readonly Vector2 offset = new Vector2(-20, 5);
+
+        public DefaultAccuracyCounter()
+        {
+            Origin = Anchor.TopRight;
+            Anchor = Anchor.TopRight;
+        }
+
+        [Resolved(canBeNull: true)]
+        private HUDOverlay hud { get; set; }
+
+        [BackgroundDependencyLoader]
+        private void load(OsuColour colours)
+        {
+            Colour = colours.BlueLighter;
+        }
+
+        protected override void Update()
+        {
+            base.Update();
+
+            if (hud?.ScoreCounter.Drawable is DefaultScoreCounter score)
+            {
+                // for now align with the score counter. eventually this will be user customisable.
+                Anchor = Anchor.TopLeft;
+                Position = Parent.ToLocalSpace(score.ScreenSpaceDrawQuad.TopLeft) + offset;
+            }
+        }
+    }
+}

osu.Game/Screens/Play/HUD/DefaultComboCounter.cs

@@ -4,18 +4,23 @@
 using System;
 using osu.Framework.Allocation;
 using osu.Framework.Graphics;
+using osu.Game.Graphics;
 using osu.Game.Graphics.Sprites;
+using osu.Game.Graphics.UserInterface;
+using osuTK;
 
-namespace osu.Game.Graphics.UserInterface
+namespace osu.Game.Screens.Play.HUD
 {
-    /// <summary>
+    public class DefaultComboCounter : RollingCounter<int>, IComboCounter
-    /// Used as an accuracy counter. Represented visually as a percentage.
-    /// </summary>
-    public class SimpleComboCounter : RollingCounter<int>
     {
+        private readonly Vector2 offset = new Vector2(20, 5);
+
         protected override double RollingDuration => 750;
 
-        public SimpleComboCounter()
+        [Resolved(canBeNull: true)]
+        private HUDOverlay hud { get; set; }
+
+        public DefaultComboCounter()
         {
             Current.Value = DisplayedCount = 0;
         }
@@ -23,6 +28,17 @@ namespace osu.Game.Graphics.UserInterface
         [BackgroundDependencyLoader]
         private void load(OsuColour colours) => Colour = colours.BlueLighter;
 
+        protected override void Update()
+        {
+            base.Update();
+
+            if (hud?.ScoreCounter.Drawable is DefaultScoreCounter score)
+            {
+                // for now align with the score counter. eventually this will be user customisable.
+                Position = Parent.ToLocalSpace(score.ScreenSpaceDrawQuad.TopRight) + offset;
+            }
+        }
+
         protected override string FormatCount(int count)
         {
             return $@"{count}x";

osu.Game/Screens/Play/HUD/DefaultHealthDisplay.cs

@@ -16,7 +16,7 @@ using osu.Framework.Utils;
 
 namespace osu.Game.Screens.Play.HUD
 {
-    public class StandardHealthDisplay : HealthDisplay, IHasAccentColour
+    public class DefaultHealthDisplay : HealthDisplay, IHasAccentColour
     {
         /// <summary>
         /// The base opacity of the glow.
@@ -71,8 +71,12 @@ namespace osu.Game.Screens.Play.HUD
             }
         }
 
-        public StandardHealthDisplay()
+        public DefaultHealthDisplay()
         {
+            Size = new Vector2(1, 5);
+            RelativeSizeAxes = Axes.X;
+            Margin = new MarginPadding { Top = 20 };
+
             Children = new Drawable[]
             {
                 new Box
@@ -103,13 +107,7 @@ namespace osu.Game.Screens.Play.HUD
             GlowColour = colours.BlueDarker;
         }
 
-        public void Flash(JudgementResult result)
+        public override void Flash(JudgementResult result) => Scheduler.AddOnce(flash);
-        {
-            if (!result.IsHit)
-                return;
-
-            Scheduler.AddOnce(flash);
-        }
 
         private void flash()
         {

osu.Game/Screens/Play/HUD/DefaultScoreCounter.cs

@@ -0,0 +1,35 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Framework.Allocation;
+using osu.Framework.Graphics;
+using osu.Game.Graphics;
+using osu.Game.Graphics.UserInterface;
+
+namespace osu.Game.Screens.Play.HUD
+{
+    public class DefaultScoreCounter : ScoreCounter
+    {
+        public DefaultScoreCounter()
+            : base(6)
+        {
+            Anchor = Anchor.TopCentre;
+            Origin = Anchor.TopCentre;
+        }
+
+        [Resolved(canBeNull: true)]
+        private HUDOverlay hud { get; set; }
+
+        [BackgroundDependencyLoader]
+        private void load(OsuColour colours)
+        {
+            Colour = colours.BlueLighter;
+
+            // todo: check if default once health display is skinnable
+            hud?.ShowHealthbar.BindValueChanged(healthBar =>
+            {
+                this.MoveToY(healthBar.NewValue ? 30 : 0, HUDOverlay.FADE_DURATION, HUDOverlay.FADE_EASING);
+            }, true);
+        }
+    }
+}

osu.Game/Screens/Play/HUD/HealthDisplay.cs

@@ -3,6 +3,7 @@
 
 using osu.Framework.Bindables;
 using osu.Framework.Graphics.Containers;
+using osu.Game.Rulesets.Judgements;
 using osu.Game.Rulesets.Scoring;
 using osu.Game.Rulesets.UI;
 
@@ -12,14 +13,18 @@ namespace osu.Game.Screens.Play.HUD
     /// A container for components displaying the current player health.
     /// Gets bound automatically to the <see cref="HealthProcessor"/> when inserted to <see cref="DrawableRuleset.Overlays"/> hierarchy.
     /// </summary>
-    public abstract class HealthDisplay : Container
+    public abstract class HealthDisplay : Container, IHealthDisplay
     {
-        public readonly BindableDouble Current = new BindableDouble(1)
+        public Bindable<double> Current { get; } = new BindableDouble(1)
         {
             MinValue = 0,
             MaxValue = 1
         };
 
+        public virtual void Flash(JudgementResult result)
+        {
+        }
+
         /// <summary>
         /// Bind the tracked fields of <see cref="HealthProcessor"/> to this health display.
         /// </summary>

osu.Game/Screens/Play/HUD/HitErrorDisplay.cs

@@ -66,54 +66,69 @@ namespace osu.Game.Screens.Play.HUD
             switch (type.NewValue)
             {
                 case ScoreMeterType.HitErrorBoth:
-                    createBar(false);
+                    createBar(Anchor.CentreLeft);
-                    createBar(true);
+                    createBar(Anchor.CentreRight);
                     break;
 
                 case ScoreMeterType.HitErrorLeft:
-                    createBar(false);
+                    createBar(Anchor.CentreLeft);
                     break;
 
                 case ScoreMeterType.HitErrorRight:
-                    createBar(true);
+                    createBar(Anchor.CentreRight);
+                    break;
+
+                case ScoreMeterType.HitErrorBottom:
+                    createBar(Anchor.BottomCentre);
                     break;
 
                 case ScoreMeterType.ColourBoth:
-                    createColour(false);
+                    createColour(Anchor.CentreLeft);
-                    createColour(true);
+                    createColour(Anchor.CentreRight);
                     break;
 
                 case ScoreMeterType.ColourLeft:
-                    createColour(false);
+                    createColour(Anchor.CentreLeft);
                     break;
 
                 case ScoreMeterType.ColourRight:
-                    createColour(true);
+                    createColour(Anchor.CentreRight);
+                    break;
+
+                case ScoreMeterType.ColourBottom:
+                    createColour(Anchor.BottomCentre);
                     break;
             }
         }
 
-        private void createBar(bool rightAligned)
+        private void createBar(Anchor anchor)
         {
+            bool rightAligned = (anchor & Anchor.x2) > 0;
+            bool bottomAligned = (anchor & Anchor.y2) > 0;
+
             var display = new BarHitErrorMeter(hitWindows, rightAligned)
             {
                 Margin = new MarginPadding(margin),
-                Anchor = rightAligned ? Anchor.CentreRight : Anchor.CentreLeft,
+                Anchor = anchor,
-                Origin = rightAligned ? Anchor.CentreRight : Anchor.CentreLeft,
+                Origin = bottomAligned ? Anchor.CentreLeft : anchor,
                 Alpha = 0,
+                Rotation = bottomAligned ? 270 : 0
             };
 
             completeDisplayLoading(display);
         }
 
-        private void createColour(bool rightAligned)
+        private void createColour(Anchor anchor)
         {
+            bool bottomAligned = (anchor & Anchor.y2) > 0;
+
             var display = new ColourHitErrorMeter(hitWindows)
             {
                 Margin = new MarginPadding(margin),
-                Anchor = rightAligned ? Anchor.CentreRight : Anchor.CentreLeft,
+                Anchor = anchor,
-                Origin = rightAligned ? Anchor.CentreRight : Anchor.CentreLeft,
+                Origin = bottomAligned ? Anchor.CentreLeft : anchor,
                 Alpha = 0,
+                Rotation = bottomAligned ? 270 : 0
             };
 
             completeDisplayLoading(display);

osu.Game/Screens/Play/HUD/HitErrorMeters/BarHitErrorMeter.cs

@@ -99,7 +99,9 @@ namespace osu.Game.Screens.Play.HUD.HitErrorMeters
                                 Size = new Vector2(10),
                                 Icon = FontAwesome.Solid.ShippingFast,
                                 Anchor = Anchor.TopCentre,
-                                Origin = Anchor.TopCentre,
+                                Origin = Anchor.Centre,
+                                // undo any layout rotation to display the icon the correct orientation
+                                Rotation = -Rotation,
                             },
                             new SpriteIcon
                             {
@@ -107,7 +109,9 @@ namespace osu.Game.Screens.Play.HUD.HitErrorMeters
                                 Size = new Vector2(10),
                                 Icon = FontAwesome.Solid.Bicycle,
                                 Anchor = Anchor.BottomCentre,
-                                Origin = Anchor.BottomCentre,
+                                Origin = Anchor.Centre,
+                                // undo any layout rotation to display the icon the correct orientation
+                                Rotation = -Rotation,
                             }
                         }
                     },

osu.Game/Screens/Play/HUD/IAccuracyCounter.cs

@@ -0,0 +1,19 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Framework.Bindables;
+using osu.Framework.Graphics;
+
+namespace osu.Game.Screens.Play.HUD
+{
+    /// <summary>
+    /// An interface providing a set of methods to update a accuracy counter.
+    /// </summary>
+    public interface IAccuracyCounter : IDrawable
+    {
+        /// <summary>
+        /// The current accuracy to be displayed.
+        /// </summary>
+        Bindable<double> Current { get; }
+    }
+}

osu.Game/Screens/Play/HUD/IComboCounter.cs

@@ -0,0 +1,19 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Framework.Bindables;
+using osu.Framework.Graphics;
+
+namespace osu.Game.Screens.Play.HUD
+{
+    /// <summary>
+    /// An interface providing a set of methods to update a combo counter.
+    /// </summary>
+    public interface IComboCounter : IDrawable
+    {
+        /// <summary>
+        /// The current combo to be displayed.
+        /// </summary>
+        Bindable<int> Current { get; }
+    }
+}

osu.Game/Screens/Play/HUD/IHealthDisplay.cs

@@ -0,0 +1,26 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Framework.Bindables;
+using osu.Framework.Graphics;
+using osu.Game.Rulesets.Judgements;
+
+namespace osu.Game.Screens.Play.HUD
+{
+    /// <summary>
+    /// An interface providing a set of methods to update a health display.
+    /// </summary>
+    public interface IHealthDisplay : IDrawable
+    {
+        /// <summary>
+        /// The current health to be displayed.
+        /// </summary>
+        Bindable<double> Current { get; }
+
+        /// <summary>
+        /// Flash the display for a specified result type.
+        /// </summary>
+        /// <param name="result">The result type.</param>
+        void Flash(JudgementResult result);
+    }
+}

osu.Game/Screens/Play/HUD/IScoreCounter.cs

@@ -0,0 +1,19 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Framework.Bindables;
+using osu.Framework.Graphics;
+
+namespace osu.Game.Screens.Play.HUD
+{
+    /// <summary>
+    /// An interface providing a set of methods to update a score counter.
+    /// </summary>
+    public interface IScoreCounter : IDrawable
+    {
+        /// <summary>
+        /// The current score to be displayed.
+        /// </summary>
+        Bindable<double> Current { get; }
+    }
+}

osu.Game/Screens/Play/HUD/LegacyComboCounter.cs

@@ -0,0 +1,252 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Framework.Allocation;
+using osu.Framework.Bindables;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Graphics.Sprites;
+using osu.Game.Graphics.Sprites;
+using osu.Game.Skinning;
+using osuTK;
+
+namespace osu.Game.Screens.Play.HUD
+{
+    /// <summary>
+    /// Uses the 'x' symbol and has a pop-out effect while rolling over.
+    /// </summary>
+    public class LegacyComboCounter : CompositeDrawable, IComboCounter
+    {
+        public Bindable<int> Current { get; } = new BindableInt { MinValue = 0, };
+
+        private uint scheduledPopOutCurrentId;
+
+        private const double pop_out_duration = 150;
+
+        private const Easing pop_out_easing = Easing.None;
+
+        private const double fade_out_duration = 100;
+
+        /// <summary>
+        /// Duration in milliseconds for the counter roll-up animation for each element.
+        /// </summary>
+        private const double rolling_duration = 20;
+
+        private Drawable popOutCount;
+
+        private Drawable displayedCountSpriteText;
+
+        private int previousValue;
+
+        private int displayedCount;
+
+        private bool isRolling;
+
+        [Resolved]
+        private ISkinSource skin { get; set; }
+
+        public LegacyComboCounter()
+        {
+            AutoSizeAxes = Axes.Both;
+
+            Anchor = Anchor.BottomLeft;
+            Origin = Anchor.BottomLeft;
+
+            Margin = new MarginPadding(10);
+
+            Scale = new Vector2(1.2f);
+        }
+
+        /// <summary>
+        /// Value shown at the current moment.
+        /// </summary>
+        public virtual int DisplayedCount
+        {
+            get => displayedCount;
+            private set
+            {
+                if (displayedCount.Equals(value))
+                    return;
+
+                if (isRolling)
+                    onDisplayedCountRolling(displayedCount, value);
+                else if (displayedCount + 1 == value)
+                    onDisplayedCountIncrement(value);
+                else
+                    onDisplayedCountChange(value);
+
+                displayedCount = value;
+            }
+        }
+
+        [BackgroundDependencyLoader]
+        private void load()
+        {
+            InternalChildren = new[]
+            {
+                displayedCountSpriteText = createSpriteText().With(s =>
+                {
+                    s.Alpha = 0;
+                }),
+                popOutCount = createSpriteText().With(s =>
+                {
+                    s.Alpha = 0;
+                    s.Margin = new MarginPadding(0.05f);
+                })
+            };
+
+            Current.ValueChanged += combo => updateCount(combo.NewValue == 0);
+        }
+
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            ((IHasText)displayedCountSpriteText).Text = formatCount(Current.Value);
+
+            displayedCountSpriteText.Anchor = Anchor;
+            displayedCountSpriteText.Origin = Origin;
+            popOutCount.Origin = Origin;
+            popOutCount.Anchor = Anchor;
+
+            updateCount(false);
+        }
+
+        private void updateCount(bool rolling)
+        {
+            int prev = previousValue;
+            previousValue = Current.Value;
+
+            if (!IsLoaded)
+                return;
+
+            if (!rolling)
+            {
+                FinishTransforms(false, nameof(DisplayedCount));
+                isRolling = false;
+                DisplayedCount = prev;
+
+                if (prev + 1 == Current.Value)
+                    onCountIncrement(prev, Current.Value);
+                else
+                    onCountChange(prev, Current.Value);
+            }
+            else
+            {
+                onCountRolling(displayedCount, Current.Value);
+                isRolling = true;
+            }
+        }
+
+        private void transformPopOut(int newValue)
+        {
+            ((IHasText)popOutCount).Text = formatCount(newValue);
+
+            popOutCount.ScaleTo(1.6f);
+            popOutCount.FadeTo(0.75f);
+            popOutCount.MoveTo(Vector2.Zero);
+
+            popOutCount.ScaleTo(1, pop_out_duration, pop_out_easing);
+            popOutCount.FadeOut(pop_out_duration, pop_out_easing);
+            popOutCount.MoveTo(displayedCountSpriteText.Position, pop_out_duration, pop_out_easing);
+        }
+
+        private void transformNoPopOut(int newValue)
+        {
+            ((IHasText)displayedCountSpriteText).Text = formatCount(newValue);
+
+            displayedCountSpriteText.ScaleTo(1);
+        }
+
+        private void transformPopOutSmall(int newValue)
+        {
+            ((IHasText)displayedCountSpriteText).Text = formatCount(newValue);
+            displayedCountSpriteText.ScaleTo(1.1f);
+            displayedCountSpriteText.ScaleTo(1, pop_out_duration, pop_out_easing);
+        }
+
+        private void scheduledPopOutSmall(uint id)
+        {
+            // Too late; scheduled task invalidated
+            if (id != scheduledPopOutCurrentId)
+                return;
+
+            DisplayedCount++;
+        }
+
+        private void onCountIncrement(int currentValue, int newValue)
+        {
+            scheduledPopOutCurrentId++;
+
+            if (DisplayedCount < currentValue)
+                DisplayedCount++;
+
+            displayedCountSpriteText.Show();
+
+            transformPopOut(newValue);
+
+            uint newTaskId = scheduledPopOutCurrentId;
+
+            Scheduler.AddDelayed(delegate
+            {
+                scheduledPopOutSmall(newTaskId);
+            }, pop_out_duration);
+        }
+
+        private void onCountRolling(int currentValue, int newValue)
+        {
+            scheduledPopOutCurrentId++;
+
+            // Hides displayed count if was increasing from 0 to 1 but didn't finish
+            if (currentValue == 0 && newValue == 0)
+                displayedCountSpriteText.FadeOut(fade_out_duration);
+
+            transformRoll(currentValue, newValue);
+        }
+
+        private void onCountChange(int currentValue, int newValue)
+        {
+            scheduledPopOutCurrentId++;
+
+            if (newValue == 0)
+                displayedCountSpriteText.FadeOut();
+
+            DisplayedCount = newValue;
+        }
+
+        private void onDisplayedCountRolling(int currentValue, int newValue)
+        {
+            if (newValue == 0)
+                displayedCountSpriteText.FadeOut(fade_out_duration);
+            else
+                displayedCountSpriteText.Show();
+
+            transformNoPopOut(newValue);
+        }
+
+        private void onDisplayedCountChange(int newValue)
+        {
+            displayedCountSpriteText.FadeTo(newValue == 0 ? 0 : 1);
+            transformNoPopOut(newValue);
+        }
+
+        private void onDisplayedCountIncrement(int newValue)
+        {
+            displayedCountSpriteText.Show();
+            transformPopOutSmall(newValue);
+        }
+
+        private void transformRoll(int currentValue, int newValue) =>
+            this.TransformTo(nameof(DisplayedCount), newValue, getProportionalDuration(currentValue, newValue), Easing.None);
+
+        private string formatCount(int count) => $@"{count}x";
+
+        private double getProportionalDuration(int currentValue, int newValue)
+        {
+            double difference = currentValue > newValue ? currentValue - newValue : newValue - currentValue;
+            return difference * rolling_duration;
+        }
+
+        private OsuSpriteText createSpriteText() => (OsuSpriteText)skin.GetDrawableComponent(new HUDSkinComponent(HUDSkinComponents.ComboText));
+    }
+}

osu.Game/Screens/Play/HUD/ModDisplay.cs

@@ -48,22 +48,29 @@ namespace osu.Game.Screens.Play.HUD
         {
             AutoSizeAxes = Axes.Both;
 
-            Children = new Drawable[]
+            Child = new FillFlowContainer
             {
-                iconsContainer = new ReverseChildIDFillFlowContainer<ModIcon>
+                Anchor = Anchor.TopCentre,
+                Origin = Anchor.TopCentre,
+                AutoSizeAxes = Axes.Both,
+                Direction = FillDirection.Vertical,
+                Children = new Drawable[]
                 {
-                    Anchor = Anchor.TopCentre,
+                    iconsContainer = new ReverseChildIDFillFlowContainer<ModIcon>
-                    Origin = Anchor.TopCentre,
+                    {
-                    AutoSizeAxes = Axes.Both,
+                        Anchor = Anchor.TopCentre,
-                    Direction = FillDirection.Horizontal,
+                        Origin = Anchor.TopCentre,
+                        AutoSizeAxes = Axes.Both,
+                        Direction = FillDirection.Horizontal,
+                    },
+                    unrankedText = new OsuSpriteText
+                    {
+                        Anchor = Anchor.TopCentre,
+                        Origin = Anchor.TopCentre,
+                        Text = @"/ UNRANKED /",
+                        Font = OsuFont.Numeric.With(size: 12)
+                    }
                 },
-                unrankedText = new OsuSpriteText
-                {
-                    Anchor = Anchor.BottomCentre,
-                    Origin = Anchor.TopCentre,
-                    Text = @"/ UNRANKED /",
-                    Font = OsuFont.Numeric.With(size: 12)
-                }
             };
 
             Current.ValueChanged += mods =>

osu.Game/Screens/Play/HUD/PlayerSettingsOverlay.cs

@@ -20,14 +20,13 @@ namespace osu.Game.Screens.Play.HUD
 
         public readonly VisualSettings VisualSettings;
 
-        //public readonly CollectionSettings CollectionSettings;
-
-        //public readonly DiscussionSettings DiscussionSettings;
-
         public PlayerSettingsOverlay()
         {
             AlwaysPresent = true;
-            RelativeSizeAxes = Axes.Both;
+
+            Anchor = Anchor.TopRight;
+            Origin = Anchor.TopRight;
+            AutoSizeAxes = Axes.Both;
 
             Child = new FillFlowContainer<PlayerSettingsGroup>
             {
@@ -36,7 +35,6 @@ namespace osu.Game.Screens.Play.HUD
                 AutoSizeAxes = Axes.Both,
                 Direction = FillDirection.Vertical,
                 Spacing = new Vector2(0, 20),
-                Margin = new MarginPadding { Top = 100, Right = 10 },
                 Children = new PlayerSettingsGroup[]
                 {
                     //CollectionSettings = new CollectionSettings(),

osu.Game/Screens/Play/HUD/SkinnableAccuracyCounter.cs

@@ -0,0 +1,29 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Framework.Bindables;
+using osu.Game.Skinning;
+
+namespace osu.Game.Screens.Play.HUD
+{
+    public class SkinnableAccuracyCounter : SkinnableDrawable, IAccuracyCounter
+    {
+        public Bindable<double> Current { get; } = new Bindable<double>();
+
+        public SkinnableAccuracyCounter()
+            : base(new HUDSkinComponent(HUDSkinComponents.AccuracyCounter), _ => new DefaultAccuracyCounter())
+        {
+            CentreComponent = false;
+        }
+
+        private IAccuracyCounter skinnedCounter;
+
+        protected override void SkinChanged(ISkinSource skin, bool allowFallback)
+        {
+            base.SkinChanged(skin, allowFallback);
+
+            skinnedCounter = Drawable as IAccuracyCounter;
+            skinnedCounter?.Current.BindTo(Current);
+        }
+    }
+}

osu.Game/Screens/Play/HUD/SkinnableComboCounter.cs

@@ -0,0 +1,29 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Framework.Bindables;
+using osu.Game.Skinning;
+
+namespace osu.Game.Screens.Play.HUD
+{
+    public class SkinnableComboCounter : SkinnableDrawable, IComboCounter
+    {
+        public Bindable<int> Current { get; } = new Bindable<int>();
+
+        public SkinnableComboCounter()
+            : base(new HUDSkinComponent(HUDSkinComponents.ComboCounter), skinComponent => new DefaultComboCounter())
+        {
+            CentreComponent = false;
+        }
+
+        private IComboCounter skinnedCounter;
+
+        protected override void SkinChanged(ISkinSource skin, bool allowFallback)
+        {
+            base.SkinChanged(skin, allowFallback);
+
+            skinnedCounter = Drawable as IComboCounter;
+            skinnedCounter?.Current.BindTo(Current);
+        }
+    }
+}

osu.Game/Screens/Play/HUD/SkinnableScoreCounter.cs

@@ -0,0 +1,29 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Framework.Bindables;
+using osu.Game.Skinning;
+
+namespace osu.Game.Screens.Play.HUD
+{
+    public class SkinnableScoreCounter : SkinnableDrawable, IScoreCounter
+    {
+        public Bindable<double> Current { get; } = new Bindable<double>();
+
+        public SkinnableScoreCounter()
+            : base(new HUDSkinComponent(HUDSkinComponents.ScoreCounter), _ => new DefaultScoreCounter())
+        {
+            CentreComponent = false;
+        }
+
+        private IScoreCounter skinnedCounter;
+
+        protected override void SkinChanged(ISkinSource skin, bool allowFallback)
+        {
+            base.SkinChanged(skin, allowFallback);
+
+            skinnedCounter = Drawable as IScoreCounter;
+            skinnedCounter?.Current.BindTo(Current);
+        }
+    }
+}