Merge pull request #3405 from peppy/update-framework

Update framework

README.md

@@ -24,7 +24,9 @@ Clone the repository including submodules
 Build and run
 
 - Using Visual Studio 2017, Rider or Visual Studio Code (configurations are included)
-- From command line using `dotnet run --project osu.Desktop`
+- From command line using `dotnet run --project osu.Desktop`. When building for non-development purposes, add `-c Release` to gain higher performance.
+
+Note: If you run from command line under linux, you will need to prefix the output folder to your `LD_LIBRARY_PATH`. See `.vscode/launch.json` for an example
 
 If you run into issues building you may need to restore nuget packages (commonly via `dotnet restore`). Visual Studio Code users must run `Restore` task from debug tab before attempt to build.
 

osu.Desktop/Program.cs

@@ -63,7 +63,7 @@ namespace osu.Desktop
         {
             bool continueExecution = Interlocked.Decrement(ref allowableExceptions) >= 0;
 
-            Logger.Log($"Unhandled exception has been {(continueExecution ? "allowed with {allowableExceptions} more allowable exceptions" : "denied")} .");
+            Logger.Log($"Unhandled exception has been {(continueExecution ? $"allowed with {allowableExceptions} more allowable exceptions" : "denied")} .");
 
             // restore the stock of allowable exceptions after a short delay.
             Task.Delay(1000).ContinueWith(_ => Interlocked.Increment(ref allowableExceptions));

osu.Desktop/osu.Desktop.csproj

@@ -28,8 +28,8 @@
   <ItemGroup Label="Package References">
     <PackageReference Include="System.IO.Packaging" Version="4.5.0" />
     <PackageReference Include="ppy.squirrel.windows" Version="1.8.0.5" />
-    <PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="2.1.1" />
-    <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="2.1.1" />
+    <PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="2.1.2" />
+    <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="2.1.2" />
   </ItemGroup>
   <ItemGroup Label="Resources">
     <EmbeddedResource Include="lazer.ico" />

osu.Game.Rulesets.Catch/UI/CatcherArea.cs

@@ -407,9 +407,7 @@ namespace osu.Game.Rulesets.Catch.UI
             /// </summary>
             public void Explode()
             {
-                var fruit = caughtFruit.ToArray();
-
-                foreach (var f in fruit)
+                foreach (var f in caughtFruit.ToArray())
                     Explode(f);
             }
 
@@ -422,15 +420,15 @@ namespace osu.Game.Rulesets.Catch.UI
                     fruit.Anchor = Anchor.TopLeft;
                     fruit.Position = caughtFruit.ToSpaceOfOtherDrawable(fruit.DrawPosition, ExplodingFruitTarget);
 
-                    caughtFruit.Remove(fruit);
+                    if (!caughtFruit.Remove(fruit))
+                        // we may have already been removed by a previous operation (due to the weird OnLoadComplete scheduling).
+                        // this avoids a crash on potentially attempting to Add a fruit to ExplodingFruitTarget twice.
+                        return;
 
                     ExplodingFruitTarget.Add(fruit);
                 }
 
-                fruit.MoveToY(fruit.Y - 50, 250, Easing.OutSine)
-                 .Then()
-                 .MoveToY(fruit.Y + 50, 500, Easing.InSine);
-
+                fruit.MoveToY(fruit.Y - 50, 250, Easing.OutSine).Then().MoveToY(fruit.Y + 50, 500, Easing.InSine);
                 fruit.MoveToX(fruit.X + originalX * 6, 1000);
                 fruit.FadeOut(750);
 

osu.Game.Rulesets.Mania/Beatmaps/Patterns/Legacy/DistanceObjectPatternGenerator.cs

@@ -173,26 +173,18 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
             var pattern = new Pattern();
 
             int usableColumns = TotalColumns - RandomStart - PreviousPattern.ColumnWithObjects;
-            int nextColumn = Random.Next(RandomStart, TotalColumns);
+            int nextColumn = GetRandomColumn();
             for (int i = 0; i < Math.Min(usableColumns, noteCount); i++)
             {
                 // Find available column
-                RunWhile(() => pattern.ColumnHasObject(nextColumn) || PreviousPattern.ColumnHasObject(nextColumn), () =>
-                {
-                    nextColumn = Random.Next(RandomStart, TotalColumns);
-                });
-
+                nextColumn = FindAvailableColumn(nextColumn, pattern, PreviousPattern);
                 addToPattern(pattern, nextColumn, startTime, EndTime);
             }
 
             // This is can't be combined with the above loop due to RNG
             for (int i = 0; i < noteCount - usableColumns; i++)
             {
-                RunWhile(() => pattern.ColumnHasObject(nextColumn), () =>
-                {
-                    nextColumn = Random.Next(RandomStart, TotalColumns);
-                });
-
+                nextColumn = FindAvailableColumn(nextColumn, pattern);
                 addToPattern(pattern, nextColumn, startTime, EndTime);
             }
 
@@ -217,23 +209,13 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
 
             int nextColumn = GetColumn((HitObject as IHasXPosition)?.X ?? 0, true);
             if (convertType.HasFlag(PatternType.ForceNotStack) && PreviousPattern.ColumnWithObjects < TotalColumns)
-            {
-                RunWhile(() => PreviousPattern.ColumnHasObject(nextColumn), () =>
-                {
-                    nextColumn = Random.Next(RandomStart, TotalColumns);
-                });
-            }
+                nextColumn = FindAvailableColumn(nextColumn, PreviousPattern);
 
             int lastColumn = nextColumn;
             for (int i = 0; i < noteCount; i++)
             {
                 addToPattern(pattern, nextColumn, startTime, startTime);
-
-                RunWhile(() => nextColumn == lastColumn, () =>
-                {
-                    nextColumn = Random.Next(RandomStart, TotalColumns);
-                });
-
+                nextColumn = FindAvailableColumn(nextColumn, validation: c => c != lastColumn);
                 lastColumn = nextColumn;
                 startTime += SegmentDuration;
             }
@@ -325,7 +307,7 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
                 if (TotalColumns > 2)
                     addToPattern(pattern, nextColumn, startTime, startTime);
 
-                nextColumn = Random.Next(RandomStart, TotalColumns);
+                nextColumn = GetRandomColumn();
                 startTime += SegmentDuration;
             }
 
@@ -404,20 +386,11 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
 
             int nextColumn = GetColumn((HitObject as IHasXPosition)?.X ?? 0, true);
             if (convertType.HasFlag(PatternType.ForceNotStack) && PreviousPattern.ColumnWithObjects < TotalColumns)
-            {
-                RunWhile(() => PreviousPattern.ColumnHasObject(nextColumn), () =>
-                {
-                    nextColumn = Random.Next(RandomStart, TotalColumns);
-                });
-            }
+                nextColumn = FindAvailableColumn(nextColumn, PreviousPattern);
 
             for (int i = 0; i < columnRepeat; i++)
             {
-                RunWhile(() => pattern.ColumnHasObject(nextColumn), () =>
-                {
-                    nextColumn = Random.Next(RandomStart, TotalColumns);
-                });
-
+                nextColumn = FindAvailableColumn(nextColumn, pattern);
                 addToPattern(pattern, nextColumn, startTime, EndTime);
                 startTime += SegmentDuration;
             }
@@ -442,17 +415,12 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
 
             int holdColumn = GetColumn((HitObject as IHasXPosition)?.X ?? 0, true);
             if (convertType.HasFlag(PatternType.ForceNotStack) && PreviousPattern.ColumnWithObjects < TotalColumns)
-            {
-                RunWhile(() => PreviousPattern.ColumnHasObject(holdColumn), () =>
-                {
-                    holdColumn = Random.Next(RandomStart, TotalColumns);
-                });
-            }
+                holdColumn = FindAvailableColumn(holdColumn, PreviousPattern);
 
             // Create the hold note
             addToPattern(pattern, holdColumn, startTime, EndTime);
 
-            int nextColumn = Random.Next(RandomStart, TotalColumns);
+            int nextColumn = GetRandomColumn();
             int noteCount;
             if (ConversionDifficulty > 6.5)
                 noteCount = GetRandomNoteCount(0.63, 0);
@@ -473,11 +441,7 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
                 {
                     for (int j = 0; j < noteCount; j++)
                     {
-                        RunWhile(() => rowPattern.ColumnHasObject(nextColumn) || nextColumn == holdColumn, () =>
-                        {
-                            nextColumn = Random.Next(RandomStart, TotalColumns);
-                        });
-
+                        nextColumn = FindAvailableColumn(nextColumn, validation: c => c != holdColumn, patterns: rowPattern);
                         addToPattern(rowPattern, nextColumn, startTime, startTime);
                     }
                 }

osu.Game.Rulesets.Mania/Beatmaps/Patterns/Legacy/EndTimeObjectPatternGenerator.cs

@@ -39,34 +39,17 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
                     addToPattern(pattern, 0, generateHold);
                     break;
                 case 8:
-                    addToPattern(pattern, getNextRandomColumn(RandomStart), generateHold);
+                    addToPattern(pattern, FindAvailableColumn(GetRandomColumn(), PreviousPattern), generateHold);
                     break;
                 default:
                     if (TotalColumns > 0)
-                        addToPattern(pattern, getNextRandomColumn(0), generateHold);
+                        addToPattern(pattern, GetRandomColumn(), generateHold);
                     break;
             }
 
             return pattern;
         }
 
-        /// <summary>
-        /// Picks a random column after a column.
-        /// </summary>
-        /// <param name="start">The starting column.</param>
-        /// <returns>A random column after <paramref name="start"/>.</returns>
-        private int getNextRandomColumn(int start)
-        {
-            int nextColumn = Random.Next(start, TotalColumns);
-
-            RunWhile(() => PreviousPattern.ColumnHasObject(nextColumn), () =>
-            {
-                nextColumn = Random.Next(start, TotalColumns);
-            });
-
-            return nextColumn;
-        }
-
         /// <summary>
         /// Constructs and adds a note to a pattern.
         /// </summary>

osu.Game.Rulesets.Mania/Beatmaps/Patterns/Legacy/HitObjectPatternGenerator.cs

@@ -25,9 +25,6 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
                                          PatternType lastStair, IBeatmap originalBeatmap)
             : base(random, hitObject, beatmap, previousPattern, originalBeatmap)
         {
-            if (previousTime > hitObject.StartTime) throw new ArgumentOutOfRangeException(nameof(previousTime));
-            if (density < 0) throw new ArgumentOutOfRangeException(nameof(density));
-
             StairType = lastStair;
 
             TimingControlPoint timingPoint = beatmap.ControlPointInfo.TimingPointAt(hitObject.StartTime);
@@ -234,22 +231,27 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
             int nextColumn = GetColumn((HitObject as IHasXPosition)?.X ?? 0, true);
             for (int i = 0; i < noteCount; i++)
             {
-                RunWhile(() => pattern.ColumnHasObject(nextColumn) || PreviousPattern.ColumnHasObject(nextColumn) && !allowStacking, () =>
-                {
-                    if (convertType.HasFlag(PatternType.Gathered))
-                    {
-                        nextColumn++;
-                        if (nextColumn == TotalColumns)
-                            nextColumn = RandomStart;
-                    }
-                    else
-                        nextColumn = Random.Next(RandomStart, TotalColumns);
-                });
+                nextColumn = allowStacking
+                    ? FindAvailableColumn(nextColumn, nextColumn: getNextColumn, patterns: pattern)
+                    : FindAvailableColumn(nextColumn, nextColumn: getNextColumn, patterns: new[] { pattern, PreviousPattern });
 
                 addToPattern(pattern, nextColumn);
             }
 
             return pattern;
+
+            int getNextColumn(int last)
+            {
+                if (convertType.HasFlag(PatternType.Gathered))
+                {
+                    last++;
+                    if (last == TotalColumns)
+                        last = RandomStart;
+                }
+                else
+                    last = GetRandomColumn();
+                return last;
+            }
         }
 
         /// <summary>
@@ -295,13 +297,10 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
             int noteCount = getRandomNoteCountMirrored(centreProbability, p2, p3, out addToCentre);
 
             int columnLimit = (TotalColumns % 2 == 0 ? TotalColumns : TotalColumns - 1) / 2;
-            int nextColumn = Random.Next(RandomStart, columnLimit);
+            int nextColumn = GetRandomColumn(upperBound: columnLimit);
             for (int i = 0; i < noteCount; i++)
             {
-                RunWhile(() => pattern.ColumnHasObject(nextColumn), () =>
-                {
-                    nextColumn = Random.Next(RandomStart, columnLimit);
-                });
+                nextColumn = FindAvailableColumn(nextColumn, upperBound: columnLimit, patterns: pattern);
 
                 // Add normal note
                 addToPattern(pattern, nextColumn);

osu.Game.Rulesets.Mania/Beatmaps/Patterns/Legacy/PatternGenerator.cs

@@ -3,6 +3,7 @@
 
 using System;
 using System.Linq;
+using JetBrains.Annotations;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Mania.MathUtils;
 using osu.Game.Rulesets.Objects;
@@ -90,6 +91,7 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
         }
 
         private double? conversionDifficulty;
+
         /// <summary>
         /// A difficulty factor used for various conversion methods from osu!stable.
         /// </summary>
@@ -116,5 +118,82 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns.Legacy
                 return conversionDifficulty.Value;
             }
         }
+
+        /// <summary>
+        /// Finds a new column in which a <see cref="HitObject"/> can be placed.
+        /// This uses <see cref="GetRandomColumn"/> to pick the next candidate column.
+        /// </summary>
+        /// <param name="initialColumn">The initial column to test. This may be returned if it is already a valid column.</param>
+        /// <param name="patterns">A list of patterns for which the validity of a column should be checked against.
+        /// A column is not a valid candidate if a <see cref="HitObject"/> occupies the same column in any of the patterns.</param>
+        /// <returns>A column for which there are no <see cref="HitObject"/>s in any of <paramref name="patterns"/> occupying the same column.</returns>
+        /// <exception cref="NotEnoughColumnsException">If there are no valid candidate columns.</exception>
+        protected int FindAvailableColumn(int initialColumn, params Pattern[] patterns)
+            => FindAvailableColumn(initialColumn, null, patterns: patterns);
+
+        /// <summary>
+        /// Finds a new column in which a <see cref="HitObject"/> can be placed.
+        /// </summary>
+        /// <param name="initialColumn">The initial column to test. This may be returned if it is already a valid column.</param>
+        /// <param name="nextColumn">A function to retrieve the next column. If null, a randomisation scheme will be used.</param>
+        /// <param name="validation">A function to perform additional validation checks to determine if a column is a valid candidate for a <see cref="HitObject"/>.</param>
+        /// <param name="lowerBound">The minimum column index. If null, <see cref="RandomStart"/> is used.</param>
+        /// <param name="upperBound">The maximum column index. If null, <see cref="PatternGenerator.TotalColumns"/> is used.</param>
+        /// <param name="patterns">A list of patterns for which the validity of a column should be checked against.
+        /// A column is not a valid candidate if a <see cref="HitObject"/> occupies the same column in any of the patterns.</param>
+        /// <returns>A column which has passed the <paramref name="validation"/> check and for which there are no
+        /// <see cref="HitObject"/>s in any of <paramref name="patterns"/> occupying the same column.</returns>
+        /// <exception cref="NotEnoughColumnsException">If there are no valid candidate columns.</exception>
+        protected int FindAvailableColumn(int initialColumn, int? lowerBound = null, int? upperBound = null, Func<int, int> nextColumn = null, [InstantHandle] Func<int, bool> validation = null,
+                                          params Pattern[] patterns)
+        {
+            lowerBound = lowerBound ?? RandomStart;
+            upperBound = upperBound ?? TotalColumns;
+            nextColumn = nextColumn ?? (_ => GetRandomColumn(lowerBound, upperBound));
+
+            // Check for the initial column
+            if (isValid(initialColumn))
+                return initialColumn;
+
+            // Ensure that we have at least one free column, so that an endless loop is avoided
+            bool hasValidColumns = false;
+            for (int i = lowerBound.Value; i < upperBound.Value; i++)
+            {
+                hasValidColumns = isValid(i);
+                if (hasValidColumns)
+                    break;
+            }
+
+            if (!hasValidColumns)
+                throw new NotEnoughColumnsException();
+
+            // Iterate until a valid column is found. This is a random iteration in the default case.
+            do
+            {
+                initialColumn = nextColumn(initialColumn);
+            } while (!isValid(initialColumn));
+
+            return initialColumn;
+
+            bool isValid(int column) => validation?.Invoke(column) != false && !patterns.Any(p => p.ColumnHasObject(column));
+        }
+
+        /// <summary>
+        /// Returns a random column index in the range [<paramref name="lowerBound"/>, <paramref name="upperBound"/>).
+        /// </summary>
+        /// <param name="lowerBound">The minimum column index. If null, <see cref="RandomStart"/> is used.</param>
+        /// <param name="upperBound">The maximum column index. If null, <see cref="PatternGenerator.TotalColumns"/> is used.</param>
+        protected int GetRandomColumn(int? lowerBound = null, int? upperBound = null) => Random.Next(lowerBound ?? RandomStart, upperBound ?? TotalColumns);
+
+        /// <summary>
+        /// Occurs when mania conversion is stuck in an infinite loop unable to find columns to place new hitobjects in.
+        /// </summary>
+        public class NotEnoughColumnsException : Exception
+        {
+            public NotEnoughColumnsException()
+                : base("There were not enough columns to complete conversion.")
+            {
+            }
+        }
     }
 }

osu.Game.Rulesets.Mania/Beatmaps/Patterns/PatternGenerator.cs

@@ -3,9 +3,6 @@
 
 using System;
 using System.Collections.Generic;
-using System.Diagnostics;
-using JetBrains.Annotations;
-using osu.Framework.Logging;
 using osu.Game.Rulesets.Objects;
 
 namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns
@@ -15,14 +12,6 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns
     /// </summary>
     internal abstract class PatternGenerator
     {
-        /// <summary>
-        /// An arbitrary maximum amount of iterations to perform in <see cref="RunWhile"/>.
-        /// The specific value is not super important - enough such that no false-positives occur.
-        ///
-        /// /b/933228 requires at least 23 iterations.
-        /// </summary>
-        private const int max_rng_iterations = 30;
-
         /// <summary>
         /// The last pattern.
         /// </summary>
@@ -53,44 +42,10 @@ namespace osu.Game.Rulesets.Mania.Beatmaps.Patterns
             TotalColumns = Beatmap.TotalColumns;
         }
 
-        protected void RunWhile([InstantHandle] Func<bool> condition, Action action)
-        {
-            int iterations = 0;
-
-            while (condition())
-            {
-                if (iterations++ >= max_rng_iterations)
-                {
-                    // log an error but don't throw. we want to continue execution.
-                    Logger.Error(new ExceededAllowedIterationsException(new StackTrace(0)),
-                        "Conversion encountered errors. The beatmap may not be correctly converted.");
-                    return;
-                }
-
-                action();
-            }
-        }
-
         /// <summary>
         /// Generates the patterns for <see cref="HitObject"/>, each filled with hit objects.
         /// </summary>
         /// <returns>The <see cref="Pattern"/>s containing the hit objects.</returns>
         public abstract IEnumerable<Pattern> Generate();
-
-        /// <summary>
-        /// Denotes when a single conversion operation is in an infinitely looping state.
-        /// </summary>
-        public class ExceededAllowedIterationsException : Exception
-        {
-            private readonly string stackTrace;
-
-            public ExceededAllowedIterationsException(StackTrace stackTrace)
-            {
-                this.stackTrace = stackTrace.ToString();
-            }
-
-            public override string StackTrace => stackTrace;
-            public override string ToString() => $"{GetType().Name}: {Message}\r\n{StackTrace}";
-        }
     }
 }

osu.Game.Rulesets.Mania/Objects/Drawables/DrawableHoldNote.cs

@@ -111,6 +111,18 @@ namespace osu.Game.Rulesets.Mania.Objects.Drawables
             bodyPiece.Height = DrawHeight - Head.Height / 2 + Tail.Height / 2;
         }
 
+        protected void BeginHold()
+        {
+            holdStartTime = Time.Current;
+            bodyPiece.Hitting = true;
+        }
+
+        protected void EndHold()
+        {
+            holdStartTime = null;
+            bodyPiece.Hitting = false;
+        }
+
         public bool OnPressed(ManiaAction action)
         {
             // Make sure the action happened within the body of the hold note
@@ -123,8 +135,7 @@ namespace osu.Game.Rulesets.Mania.Objects.Drawables
             // The user has pressed during the body of the hold note, after the head note and its hit windows have passed
             // and within the limited range of the above if-statement. This state will be managed by the head note if the
             // user has pressed during the hit windows of the head note.
-            holdStartTime = Time.Current;
-
+            BeginHold();
             return true;
         }
 
@@ -137,7 +148,7 @@ namespace osu.Game.Rulesets.Mania.Objects.Drawables
             if (action != Action.Value)
                 return false;
 
-            holdStartTime = null;
+            EndHold();
 
             // If the key has been released too early, the user should not receive full score for the release
             if (!Tail.IsHit)
@@ -170,7 +181,7 @@ namespace osu.Game.Rulesets.Mania.Objects.Drawables
 
                 // The head note also handles early hits before the body, but we want accurate early hits to count as the body being held
                 // The body doesn't handle these early early hits, so we have to explicitly set the holding state here
-                holdNote.holdStartTime = Time.Current;
+                holdNote.BeginHold();
 
                 return true;
             }

osu.Game.Rulesets.Mania/Objects/Drawables/Pieces/BodyPiece.cs

@@ -32,6 +32,7 @@ namespace osu.Game.Rulesets.Mania.Objects.Drawables.Pieces
                 background = new Box { RelativeSizeAxes = Axes.Both },
                 foreground = new BufferedContainer
                 {
+                    Blending = BlendingMode.Additive,
                     RelativeSizeAxes = Axes.Both,
                     CacheDrawnFrameBuffer = true,
                     Children = new Drawable[]
@@ -73,6 +74,7 @@ namespace osu.Game.Rulesets.Mania.Objects.Drawables.Pieces
         }
 
         private Color4 accentColour;
+
         public Color4 AccentColour
         {
             get { return accentColour; }
@@ -86,6 +88,16 @@ namespace osu.Game.Rulesets.Mania.Objects.Drawables.Pieces
             }
         }
 
+        public bool Hitting
+        {
+            get { return hitting; }
+            set
+            {
+                hitting = value;
+                updateAccentColour();
+            }
+        }
+
         private Cached subtractionCache = new Cached();
 
         public override bool Invalidate(Invalidation invalidation = Invalidation.All, Drawable source = null, bool shallPropagate = true)
@@ -118,13 +130,26 @@ namespace osu.Game.Rulesets.Mania.Objects.Drawables.Pieces
             }
         }
 
+        private bool hitting;
+
         private void updateAccentColour()
         {
             if (!IsLoaded)
                 return;
 
-            foreground.Colour = AccentColour.Opacity(0.9f);
-            background.Colour = AccentColour.Opacity(0.6f);
+            foreground.Colour = AccentColour.Opacity(0.5f);
+            background.Colour = AccentColour.Opacity(0.7f);
+
+            const float animation_length = 50;
+
+            foreground.ClearTransforms(false, nameof(foreground.Colour));
+            if (hitting)
+            {
+                // wait for the next sync point
+                double synchronisedOffset = animation_length * 2 - Time.Current % (animation_length * 2);
+                using (foreground.BeginDelayedSequence(synchronisedOffset))
+                    foreground.FadeColour(AccentColour.Lighten(0.2f), animation_length).Then().FadeColour(foreground.Colour, animation_length).Loop();
+            }
 
             subtractionCache.Invalidate();
         }

osu.Game.Rulesets.Mania/UI/ManiaPlayfield.cs

@@ -26,11 +26,11 @@ namespace osu.Game.Rulesets.Mania.UI
                 throw new ArgumentException("Can't have zero or fewer stages.");
 
             GridContainer playfieldGrid;
-            InternalChild = playfieldGrid = new GridContainer
+            AddInternal(playfieldGrid = new GridContainer
             {
                 RelativeSizeAxes = Axes.Both,
                 Content = new[] { new Drawable[stageDefinitions.Count] }
-            };
+            });
 
             var normalColumnAction = ManiaAction.Key1;
             var specialColumnAction = ManiaAction.Special1;

osu.Game.Rulesets.Osu.Tests/StackingTest.cs

@@ -0,0 +1,64 @@
+// Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
+// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
+
+using System.IO;
+using System.Linq;
+using System.Text;
+using NUnit.Framework;
+using osu.Game.Beatmaps;
+using osu.Game.Rulesets.Osu.Objects;
+using osu.Game.Tests.Beatmaps;
+using Decoder = osu.Game.Beatmaps.Formats.Decoder;
+
+namespace osu.Game.Rulesets.Osu.Tests
+{
+    [TestFixture]
+    public class StackingTest
+    {
+        [Test]
+        public void TestStacking()
+        {
+            using (var stream = new MemoryStream(Encoding.UTF8.GetBytes(beatmap_data)))
+            using (var reader = new StreamReader(stream))
+            {
+                var beatmap = Decoder.GetDecoder<Beatmap>(reader).Decode(reader);
+                var converted = new TestWorkingBeatmap(beatmap).GetPlayableBeatmap(new OsuRuleset().RulesetInfo);
+
+                var objects = converted.HitObjects.ToList();
+
+                // The last hitobject triggers the stacking
+                for (int i = 0; i < objects.Count - 1; i++)
+                    Assert.AreEqual(0, ((OsuHitObject)objects[i]).StackHeight);
+            }
+        }
+
+        private const string beatmap_data = @"
+osu file format v14
+
+[General]
+StackLeniency: 0.2
+
+[Difficulty]
+ApproachRate:9.2
+SliderMultiplier:1
+SliderTickRate:0.5
+
+[TimingPoints]
+217871,6400,4,2,1,20,1,0
+217871,-800,4,2,1,20,0,0
+218071,-787.5,4,2,1,20,0,0
+218271,-775,4,2,1,20,0,0
+218471,-762.5,4,2,1,20,0,0
+218671,-750,4,2,1,20,0,0
+240271,-10,4,2,0,5,0,0
+
+[HitObjects]
+311,185,217871,6,0,L|318:158,1,25
+311,185,218071,2,0,L|335:170,1,25
+311,185,218271,2,0,L|338:192,1,25
+311,185,218471,2,0,L|325:209,1,25
+311,185,218671,2,0,L|304:212,1,25
+311,185,240271,5,0,0:0:0:0:
+";
+    }
+}

osu.Game.Rulesets.Osu.Tests/TestCaseHitCircle.cs

@@ -85,7 +85,7 @@ namespace osu.Game.Rulesets.Osu.Tests
             }
         }
 
-        private class TestDrawableHitCircle : DrawableHitCircle
+        protected class TestDrawableHitCircle : DrawableHitCircle
         {
             private readonly bool auto;
 
@@ -94,6 +94,8 @@ namespace osu.Game.Rulesets.Osu.Tests
                 this.auto = auto;
             }
 
+            public void TriggerJudgement() => UpdateResult(true);
+
             protected override void CheckForResult(bool userTriggered, double timeOffset)
             {
                 if (auto && !userTriggered && timeOffset > 0)

osu.Game.Rulesets.Osu.Tests/TestCaseShaking.cs

@@ -0,0 +1,23 @@
+// Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
+// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
+
+using osu.Framework.Graphics;
+using osu.Framework.MathUtils;
+using osu.Game.Rulesets.Scoring;
+
+namespace osu.Game.Rulesets.Osu.Tests
+{
+    public class TestCaseShaking : TestCaseHitCircle
+    {
+        public override void Add(Drawable drawable)
+        {
+            base.Add(drawable);
+
+            if (drawable is TestDrawableHitCircle hitObject)
+            {
+                Scheduler.AddDelayed(() => hitObject.TriggerJudgement(),
+                    hitObject.HitObject.StartTime - (hitObject.HitObject.HitWindows.HalfWindowFor(HitResult.Miss) + RNG.Next(0, 300)) - Time.Current);
+            }
+        }
+    }
+}

osu.Game.Rulesets.Osu/Beatmaps/OsuBeatmapProcessor.cs

@@ -15,9 +15,9 @@ namespace osu.Game.Rulesets.Osu.Beatmaps
         {
         }
 
-        public override void PreProcess()
+        public override void PostProcess()
         {
-            base.PreProcess();
+            base.PostProcess();
             applyStacking((Beatmap<OsuHitObject>)Beatmap);
         }
 

osu.Game.Rulesets.Osu/Mods/OsuModRelax.cs

@@ -2,14 +2,89 @@
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
 using System;
+using System.Collections.Generic;
 using System.Linq;
+using osu.Framework.Input.States;
 using osu.Game.Rulesets.Mods;
+using osu.Game.Rulesets.Objects.Types;
+using osu.Game.Rulesets.Osu.Objects;
+using osu.Game.Rulesets.Osu.Objects.Drawables;
+using osu.Game.Rulesets.UI;
+using static osu.Game.Input.Handlers.ReplayInputHandler;
 
 namespace osu.Game.Rulesets.Osu.Mods
 {
-    public class OsuModRelax : ModRelax
+    public class OsuModRelax : ModRelax, IApplicableFailOverride, IUpdatableByPlayfield, IApplicableToRulesetContainer<OsuHitObject>
     {
         public override string Description => @"You don't need to click. Give your clicking/tapping fingers a break from the heat of things.";
         public override Type[] IncompatibleMods => base.IncompatibleMods.Append(typeof(OsuModAutopilot)).ToArray();
+
+        public bool AllowFail => false;
+
+        public void Update(Playfield playfield)
+        {
+            bool requiresHold = false;
+            bool requiresHit = false;
+
+            const float relax_leniency = 3;
+
+            foreach (var drawable in playfield.HitObjectContainer.AliveObjects)
+            {
+                if (!(drawable is DrawableOsuHitObject osuHit))
+                    continue;
+
+                double time = osuHit.Clock.CurrentTime;
+                double relativetime = time - osuHit.HitObject.StartTime;
+
+                if (time < osuHit.HitObject.StartTime - relax_leniency) continue;
+
+                if (osuHit.HitObject is IHasEndTime hasEnd && time > hasEnd.EndTime || osuHit.IsHit)
+                    continue;
+
+                requiresHit |= osuHit is DrawableHitCircle && osuHit.IsHovered && osuHit.HitObject.HitWindows.CanBeHit(relativetime);
+                requiresHold |= osuHit is DrawableSlider slider && (slider.Ball.IsHovered || osuHit.IsHovered) || osuHit is DrawableSpinner;
+            }
+
+            if (requiresHit)
+            {
+                addAction(false);
+                addAction(true);
+            }
+
+            addAction(requiresHold);
+        }
+
+        private bool wasHit;
+        private bool wasLeft;
+
+        private OsuInputManager osuInputManager;
+
+        private void addAction(bool hitting)
+        {
+            if (wasHit == hitting)
+                return;
+
+            wasHit = hitting;
+
+            var state = new ReplayState<OsuAction>
+            {
+                PressedActions = new List<OsuAction>()
+            };
+
+            if (hitting)
+            {
+                state.PressedActions.Add(wasLeft ? OsuAction.LeftButton : OsuAction.RightButton);
+                wasLeft = !wasLeft;
+            }
+
+            osuInputManager.HandleCustomInput(new InputState(), state);
+        }
+
+        public void ApplyToRulesetContainer(RulesetContainer<OsuHitObject> rulesetContainer)
+        {
+            // grab the input manager for future use.
+            osuInputManager = (OsuInputManager)rulesetContainer.KeyBindingInputManager;
+            osuInputManager.AllowUserPresses = false;
+        }
     }
 }

osu.Game.Rulesets.Osu/Objects/Drawables/DrawableHitCircle.cs

@@ -88,7 +88,10 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
 
             var result = HitObject.HitWindows.ResultFor(timeOffset);
             if (result == HitResult.None)
+            {
+                Shake(Math.Abs(timeOffset) - HitObject.HitWindows.HalfWindowFor(HitResult.Miss));
                 return;
+            }
 
             ApplyResult(r => r.Type = result);
         }

osu.Game.Rulesets.Osu/Objects/Drawables/DrawableOsuHitObject.cs

@@ -10,19 +10,29 @@ using osu.Game.Rulesets.Osu.Judgements;
 using osu.Game.Rulesets.Scoring;
 using osu.Game.Skinning;
 using OpenTK.Graphics;
+using osu.Game.Graphics.Containers;
 
 namespace osu.Game.Rulesets.Osu.Objects.Drawables
 {
     public class DrawableOsuHitObject : DrawableHitObject<OsuHitObject>
     {
-        public override bool IsPresent => base.IsPresent || State.Value == ArmedState.Idle && Time.Current >= HitObject.StartTime - HitObject.TimePreempt;
+        public override bool IsPresent => base.IsPresent || State.Value == ArmedState.Idle && Clock?.CurrentTime >= HitObject.StartTime - HitObject.TimePreempt;
+
+        private readonly ShakeContainer shakeContainer;
 
         protected DrawableOsuHitObject(OsuHitObject hitObject)
             : base(hitObject)
         {
+            base.AddInternal(shakeContainer = new ShakeContainer { RelativeSizeAxes = Axes.Both });
             Alpha = 0;
         }
 
+        // Forward all internal management to shakeContainer.
+        // This is a bit ugly but we don't have the concept of InternalContent so it'll have to do for now. (https://github.com/ppy/osu-framework/issues/1690)
+        protected override void AddInternal(Drawable drawable) => shakeContainer.Add(drawable);
+        protected override void ClearInternal(bool disposeChildren = true) => shakeContainer.Clear(disposeChildren);
+        protected override bool RemoveInternal(Drawable drawable) => shakeContainer.Remove(drawable);
+
         protected sealed override void UpdateState(ArmedState state)
         {
             double transformTime = HitObject.StartTime - HitObject.TimePreempt;
@@ -68,6 +78,8 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
         private OsuInputManager osuActionInputManager;
         internal OsuInputManager OsuActionInputManager => osuActionInputManager ?? (osuActionInputManager = GetContainingInputManager() as OsuInputManager);
 
+        protected virtual void Shake(double maximumLength) => shakeContainer.Shake(maximumLength);
+
         protected override JudgementResult CreateResult(Judgement judgement) => new OsuJudgementResult(judgement);
     }
 }

osu.Game.Rulesets.Osu/Objects/Drawables/DrawableSlider.cs

@@ -44,14 +44,17 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
                 },
                 ticks = new Container<DrawableSliderTick> { RelativeSizeAxes = Axes.Both },
                 repeatPoints = new Container<DrawableRepeatPoint> { RelativeSizeAxes = Axes.Both },
-                Ball = new SliderBall(s)
+                Ball = new SliderBall(s, this)
                 {
                     BypassAutoSizeAxes = Axes.Both,
                     Scale = new Vector2(s.Scale),
                     AlwaysPresent = true,
                     Alpha = 0
                 },
-                HeadCircle = new DrawableSliderHead(s, s.HeadCircle),
+                HeadCircle = new DrawableSliderHead(s, s.HeadCircle)
+                {
+                    OnShake = Shake
+                },
                 TailCircle = new DrawableSliderTail(s, s.TailCircle)
             };
 

osu.Game.Rulesets.Osu/Objects/Drawables/DrawableSliderHead.cs

@@ -1,6 +1,7 @@
 // Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
+using System;
 using osu.Game.Rulesets.Objects.Types;
 using OpenTK;
 
@@ -28,5 +29,9 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
             if (!IsHit)
                 Position = slider.CurvePositionAt(completionProgress);
         }
+
+        public Action<double> OnShake;
+
+        protected override void Shake(double maximumLength) => OnShake?.Invoke(maximumLength);
     }
 }

osu.Game.Rulesets.Osu/Objects/Drawables/Pieces/SliderBall.cs

@@ -8,7 +8,6 @@ using osu.Framework.Graphics.Shapes;
 using osu.Framework.Input.EventArgs;
 using osu.Framework.Input.States;
 using osu.Game.Rulesets.Objects.Types;
-using OpenTK;
 using OpenTK.Graphics;
 using osu.Game.Skinning;
 
@@ -37,9 +36,11 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables.Pieces
         private readonly Slider slider;
         public readonly Drawable FollowCircle;
         private Drawable drawableBall;
+        private readonly DrawableSlider drawableSlider;
 
-        public SliderBall(Slider slider)
+        public SliderBall(Slider slider, DrawableSlider drawableSlider = null)
         {
+            this.drawableSlider = drawableSlider;
             this.slider = slider;
             Masking = true;
             AutoSizeAxes = Axes.Both;
@@ -121,9 +122,6 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables.Pieces
             return base.OnMouseMove(state);
         }
 
-        // If the current time is between the start and end of the slider, we should track mouse input regardless of the cursor position.
-        public override bool ReceiveMouseInputAt(Vector2 screenSpacePos) => canCurrentlyTrack || base.ReceiveMouseInputAt(screenSpacePos);
-
         public override void ClearTransformsAfter(double time, bool propagateChildren = false, string targetMember = null)
         {
             // Consider the case of rewinding - children's transforms are handled internally, so propagating down
@@ -158,8 +156,8 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables.Pieces
                 // Make sure to use the base version of ReceiveMouseInputAt so that we correctly check the position.
                 Tracking = canCurrentlyTrack
                            && lastState != null
-                           && base.ReceiveMouseInputAt(lastState.Mouse.NativeState.Position)
-                           && ((Parent as DrawableSlider)?.OsuActionInputManager?.PressedActions.Any(x => x == OsuAction.LeftButton || x == OsuAction.RightButton) ?? false);
+                           && ReceiveMouseInputAt(lastState.Mouse.NativeState.Position)
+                           && (drawableSlider?.OsuActionInputManager?.PressedActions.Any(x => x == OsuAction.LeftButton || x == OsuAction.RightButton) ?? false);
             }
         }
 

osu.Game.Rulesets.Osu/Objects/Drawables/Pieces/SliderBody.cs

@@ -7,14 +7,15 @@ using osu.Framework.Allocation;
 using osu.Framework.Configuration;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
-using osu.Framework.Graphics.OpenGL.Textures;
 using osu.Framework.Graphics.Lines;
 using osu.Framework.Graphics.Textures;
-using OpenTK;
 using OpenTK.Graphics.ES30;
 using OpenTK.Graphics;
 using osu.Framework.Graphics.Primitives;
 using osu.Game.Rulesets.Objects.Types;
+using OpenTK;
+using SixLabors.ImageSharp;
+using SixLabors.ImageSharp.PixelFormats;
 
 namespace osu.Game.Rulesets.Osu.Objects.Drawables.Pieces
 {
@@ -43,6 +44,7 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables.Pieces
         public double? SnakedEnd { get; private set; }
 
         private Color4 accentColour = Color4.White;
+
         /// <summary>
         /// Used to colour the path.
         /// </summary>
@@ -61,6 +63,7 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables.Pieces
         }
 
         private Color4 borderColour = Color4.White;
+
         /// <summary>
         /// Used to colour the path border.
         /// </summary>
@@ -85,6 +88,7 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables.Pieces
         private Vector2 topLeftOffset;
 
         private readonly Slider slider;
+
         public SliderBody(Slider s)
         {
             slider = s;
@@ -139,8 +143,7 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables.Pieces
             var texture = new Texture(textureWidth, 1);
 
             //initialise background
-            var raw = new RawTexture(textureWidth, 1);
-            var bytes = raw.Data;
+            var raw = new Image<Rgba32>(textureWidth, 1);
 
             const float aa_portion = 0.02f;
             const float border_portion = 0.128f;
@@ -155,19 +158,13 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables.Pieces
 
                 if (progress <= border_portion)
                 {
-                    bytes[i * 4] = (byte)(BorderColour.R * 255);
-                    bytes[i * 4 + 1] = (byte)(BorderColour.G * 255);
-                    bytes[i * 4 + 2] = (byte)(BorderColour.B * 255);
-                    bytes[i * 4 + 3] = (byte)(Math.Min(progress / aa_portion, 1) * (BorderColour.A * 255));
+                    raw[i, 0] = new Rgba32(BorderColour.R, BorderColour.G, BorderColour.B, Math.Min(progress / aa_portion, 1) * BorderColour.A);
                 }
                 else
                 {
                     progress -= border_portion;
-
-                    bytes[i * 4] = (byte)(AccentColour.R * 255);
-                    bytes[i * 4 + 1] = (byte)(AccentColour.G * 255);
-                    bytes[i * 4 + 2] = (byte)(AccentColour.B * 255);
-                    bytes[i * 4 + 3] = (byte)((opacity_at_edge - (opacity_at_edge - opacity_at_centre) * progress / gradient_portion) * (AccentColour.A * 255));
+                    raw[i, 0] = new Rgba32(AccentColour.R, AccentColour.G, AccentColour.B,
+                        (opacity_at_edge - (opacity_at_edge - opacity_at_centre) * progress / gradient_portion) * AccentColour.A);
                 }
             }
 

osu.Game.Rulesets.Osu/OsuInputManager.cs

@@ -4,6 +4,8 @@
 using System.Collections.Generic;
 using System.ComponentModel;
 using osu.Framework.Input.Bindings;
+using osu.Framework.Input.EventArgs;
+using osu.Framework.Input.States;
 using osu.Game.Rulesets.UI;
 
 namespace osu.Game.Rulesets.Osu
@@ -12,8 +14,35 @@ namespace osu.Game.Rulesets.Osu
     {
         public IEnumerable<OsuAction> PressedActions => KeyBindingContainer.PressedActions;
 
-        public OsuInputManager(RulesetInfo ruleset) : base(ruleset, 0, SimultaneousBindingMode.Unique)
+        public bool AllowUserPresses
         {
+            set => ((OsuKeyBindingContainer)KeyBindingContainer).AllowUserPresses = value;
+        }
+
+        protected override RulesetKeyBindingContainer CreateKeyBindingContainer(RulesetInfo ruleset, int variant, SimultaneousBindingMode unique)
+            => new OsuKeyBindingContainer(ruleset, variant, unique);
+
+        public OsuInputManager(RulesetInfo ruleset)
+            : base(ruleset, 0, SimultaneousBindingMode.Unique)
+        {
+        }
+
+        private class OsuKeyBindingContainer : RulesetKeyBindingContainer
+        {
+            public bool AllowUserPresses = true;
+
+            public OsuKeyBindingContainer(RulesetInfo ruleset, int variant, SimultaneousBindingMode unique)
+                : base(ruleset, variant, unique)
+            {
+            }
+
+            protected override bool OnKeyDown(InputState state, KeyDownEventArgs args) => AllowUserPresses && base.OnKeyDown(state, args);
+            protected override bool OnKeyUp(InputState state, KeyUpEventArgs args) => AllowUserPresses && base.OnKeyUp(state, args);
+            protected override bool OnJoystickPress(InputState state, JoystickEventArgs args) => AllowUserPresses && base.OnJoystickPress(state, args);
+            protected override bool OnJoystickRelease(InputState state, JoystickEventArgs args) => AllowUserPresses && base.OnJoystickRelease(state, args);
+            protected override bool OnMouseDown(InputState state, MouseDownEventArgs args) => AllowUserPresses && base.OnMouseDown(state, args);
+            protected override bool OnMouseUp(InputState state, MouseUpEventArgs args) => AllowUserPresses && base.OnMouseUp(state, args);
+            protected override bool OnScroll(InputState state) => AllowUserPresses && base.OnScroll(state);
         }
     }
 
@@ -21,6 +50,7 @@ namespace osu.Game.Rulesets.Osu
     {
         [Description("Left Button")]
         LeftButton,
+
         [Description("Right Button")]
         RightButton
     }

osu.Game.Rulesets.Osu/UI/Cursor/CursorTrail.cs

@@ -216,7 +216,7 @@ namespace osu.Game.Rulesets.Osu.UI.Cursor
 
                         Texture.DrawQuad(
                             new Quad(pos.X - Size.X / 2, pos.Y - Size.Y / 2, Size.X, Size.Y),
-                            DrawInfo.Colour,
+                            DrawColourInfo.Colour,
                             null,
                             v => Shared.VertexBuffer.Vertices[end++] = new TexturedTrailVertex
                             {

osu.Game.Rulesets.Osu/UI/OsuPlayfield.cs

@@ -61,7 +61,7 @@ namespace osu.Game.Rulesets.Osu.UI
 
         public override void PostProcess()
         {
-            connectionLayer.HitObjects = HitObjects.Objects.Select(d => d.HitObject).OfType<OsuHitObject>();
+            connectionLayer.HitObjects = HitObjectContainer.Objects.Select(d => d.HitObject).OfType<OsuHitObject>();
         }
 
         private void onNewResult(DrawableHitObject judgedObject, JudgementResult result)

osu.Game.Rulesets.Taiko/Beatmaps/TaikoBeatmapConverter.cs

@@ -62,7 +62,7 @@ namespace osu.Game.Rulesets.Taiko.Beatmaps
                 converted.HitObjects = converted.HitObjects.GroupBy(t => t.StartTime).Select(x =>
                 {
                     TaikoHitObject first = x.First();
-                    if (x.Skip(1).Any())
+                    if (x.Skip(1).Any() && !(first is Swell))
                         first.IsStrong = true;
                     return first;
                 }).ToList();

osu.Game.Tests/Visual/TestCasePreviewTrackManager.cs

@@ -25,7 +25,7 @@ namespace osu.Game.Tests.Visual
         [BackgroundDependencyLoader]
         private void load()
         {
-            AddInternal(trackManager);
+            Add(trackManager);
         }
 
         [Test]
@@ -75,7 +75,7 @@ namespace osu.Game.Tests.Visual
             TestTrackOwner owner = null;
             PreviewTrack track = null;
 
-            AddStep("get track", () => AddInternal(owner = new TestTrackOwner(track = getTrack())));
+            AddStep("get track", () => Add(owner = new TestTrackOwner(track = getTrack())));
             AddStep("start", () => track.Start());
             AddStep("attempt stop", () => trackManager.StopAnyPlaying(this));
             AddAssert("not stopped", () => track.IsRunning);
@@ -89,7 +89,7 @@ namespace osu.Game.Tests.Visual
         {
             var track = getTrack();
 
-            AddInternal(track);
+            Add(track);
 
             return track;
         }

osu.Game/Beatmaps/BeatmapManager.cs

@@ -11,6 +11,7 @@ using Microsoft.EntityFrameworkCore;
 using osu.Framework.Audio;
 using osu.Framework.Audio.Track;
 using osu.Framework.Extensions;
+using osu.Framework.Extensions.IEnumerableExtensions;
 using osu.Framework.Graphics.Textures;
 using osu.Framework.Logging;
 using osu.Framework.Platform;
@@ -62,6 +63,8 @@ namespace osu.Game.Beatmaps
 
         public override string[] HandledExtensions => new[] { ".osz" };
 
+        protected override string ImportFromStablePath => "Songs";
+
         private readonly RulesetStore rulesets;
 
         private readonly BeatmapStore beatmaps;
@@ -72,11 +75,6 @@ namespace osu.Game.Beatmaps
 
         private readonly List<DownloadBeatmapSetRequest> currentDownloads = new List<DownloadBeatmapSetRequest>();
 
-        /// <summary>
-        /// Set a storage with access to an osu-stable install for import purposes.
-        /// </summary>
-        public Func<Storage> GetStableStorage { private get; set; }
-
         public BeatmapManager(Storage storage, IDatabaseContextFactory contextFactory, RulesetStore rulesets, APIAccess api, AudioManager audioManager, IIpcHost importHost = null)
             : base(storage, contextFactory, new BeatmapStore(contextFactory), importHost)
         {
@@ -103,6 +101,11 @@ namespace osu.Game.Beatmaps
                 b.BeatmapSet = beatmapSet;
             }
 
+            validateOnlineIds(beatmapSet.Beatmaps);
+
+            foreach (BeatmapInfo b in beatmapSet.Beatmaps)
+                fetchAndPopulateOnlineIDs(b, beatmapSet.Beatmaps);
+
             // check if a set already exists with the same online id, delete if it does.
             if (beatmapSet.OnlineBeatmapSetID != null)
             {
@@ -114,11 +117,6 @@ namespace osu.Game.Beatmaps
                     Logger.Log($"Found existing beatmap set with same OnlineBeatmapSetID ({beatmapSet.OnlineBeatmapSetID}). It has been purged.", LoggingTarget.Database);
                 }
             }
-
-            validateOnlineIds(beatmapSet.Beatmaps);
-
-            foreach (BeatmapInfo b in beatmapSet.Beatmaps)
-                fetchAndPopulateOnlineIDs(b, beatmapSet.Beatmaps);
         }
 
         private void validateOnlineIds(List<BeatmapInfo> beatmaps)
@@ -195,7 +193,7 @@ namespace osu.Game.Beatmaps
 
                     downloadNotification.CompletionClickAction = () =>
                     {
-                        PresentBeatmap?.Invoke(importedBeatmap);
+                        PresentCompletedImport(importedBeatmap.Yield());
                         return true;
                     };
                     downloadNotification.State = ProgressNotificationState.Completed;
@@ -231,6 +229,12 @@ namespace osu.Game.Beatmaps
             BeatmapDownloadBegan?.Invoke(request);
         }
 
+        protected override void PresentCompletedImport(IEnumerable<BeatmapSetInfo> imported)
+        {
+            base.PresentCompletedImport(imported);
+            PresentBeatmap?.Invoke(imported.LastOrDefault());
+        }
+
         /// <summary>
         /// Get an existing download request if it exists.
         /// </summary>
@@ -311,27 +315,6 @@ namespace osu.Game.Beatmaps
         /// <returns>Results from the provided query.</returns>
         public IQueryable<BeatmapInfo> QueryBeatmaps(Expression<Func<BeatmapInfo, bool>> query) => beatmaps.Beatmaps.AsNoTracking().Where(query);
 
-        /// <summary>
-        /// Denotes whether an osu-stable installation is present to perform automated imports from.
-        /// </summary>
-        public bool StableInstallationAvailable => GetStableStorage?.Invoke() != null;
-
-        /// <summary>
-        /// This is a temporary method and will likely be replaced by a full-fledged (and more correctly placed) migration process in the future.
-        /// </summary>
-        public async Task ImportFromStable()
-        {
-            var stable = GetStableStorage?.Invoke();
-
-            if (stable == null)
-            {
-                Logger.Log("No osu!stable installation available!", LoggingTarget.Information, LogLevel.Error);
-                return;
-            }
-
-            await Task.Factory.StartNew(() => Import(stable.GetDirectories("Songs").Select(f => stable.GetFullPath(f)).ToArray()), TaskCreationOptions.LongRunning);
-        }
-
         /// <summary>
         /// Create a SHA-2 hash from the provided archive based on contained beatmap (.osu) file content.
         /// </summary>
@@ -350,7 +333,11 @@ namespace osu.Game.Beatmaps
         {
             // let's make sure there are actually .osu files to import.
             string mapName = reader.Filenames.FirstOrDefault(f => f.EndsWith(".osu"));
-            if (string.IsNullOrEmpty(mapName)) throw new InvalidOperationException("No beatmap files found in this beatmap archive.");
+            if (string.IsNullOrEmpty(mapName))
+            {
+                Logger.Log($"No beatmap files found in the beatmap archive ({reader.Name}).", LoggingTarget.Database);
+                return null;
+            }
 
             Beatmap beatmap;
             using (var stream = new StreamReader(reader.GetStream(mapName)))

osu.Game/Beatmaps/BeatmapManager_WorkingBeatmap.cs

@@ -10,7 +10,6 @@ using osu.Framework.Graphics.Textures;
 using osu.Framework.IO.Stores;
 using osu.Framework.Logging;
 using osu.Game.Beatmaps.Formats;
-using osu.Game.Graphics.Textures;
 using osu.Game.Skinning;
 using osu.Game.Storyboards;
 
@@ -45,6 +44,10 @@ namespace osu.Game.Beatmaps
 
             private string getPathForFile(string filename) => BeatmapSetInfo.Files.First(f => string.Equals(f.Filename, filename, StringComparison.InvariantCultureIgnoreCase)).FileInfo.StoragePath;
 
+            private LargeTextureStore textureStore;
+
+            protected override bool BackgroundStillValid(Texture b) => false; // bypass lazy logic. we want to return a new background each time for refcounting purposes.
+
             protected override Texture GetBackground()
             {
                 if (Metadata?.BackgroundFile == null)
@@ -52,7 +55,7 @@ namespace osu.Game.Beatmaps
 
                 try
                 {
-                    return new LargeTextureStore(new RawTextureLoaderStore(store)).Get(getPathForFile(Metadata.BackgroundFile));
+                    return (textureStore ?? (textureStore = new LargeTextureStore(new TextureLoaderStore(store)))).Get(getPathForFile(Metadata.BackgroundFile));
                 }
                 catch
                 {
@@ -73,6 +76,14 @@ namespace osu.Game.Beatmaps
                 }
             }
 
+            public override void TransferTo(WorkingBeatmap other)
+            {
+                base.TransferTo(other);
+
+                if (other is BeatmapManagerWorkingBeatmap owb && textureStore != null && BeatmapInfo.BackgroundEquals(other.BeatmapInfo))
+                    owb.textureStore = textureStore;
+            }
+
             protected override Waveform GetWaveform()
             {
                 try

osu.Game/Beatmaps/Formats/Decoder.cs

@@ -55,11 +55,11 @@ namespace osu.Game.Beatmaps.Formats
             } while (line != null && line.Length == 0);
 
             if (line == null)
-                throw new IOException(@"Unknown file format");
+                throw new IOException(@"Unknown file format (null)");
 
-            var decoder = typedDecoders.Select(d => line.StartsWith(d.Key) ? d.Value : null).FirstOrDefault();
+            var decoder = typedDecoders.Select(d => line.StartsWith(d.Key, StringComparison.InvariantCulture) ? d.Value : null).FirstOrDefault();
             if (decoder == null)
-                throw new IOException(@"Unknown file format");
+                throw new IOException($@"Unknown file format ({line})");
 
             return (Decoder<T>)decoder.Invoke(line);
         }

osu.Game/Beatmaps/Formats/LegacyBeatmapDecoder.cs

@@ -408,11 +408,8 @@ namespace osu.Game.Beatmaps.Formats
                 parser = new Rulesets.Objects.Legacy.Osu.ConvertHitObjectParser(getOffsetTime(), FormatVersion);
 
             var obj = parser.Parse(line);
-
             if (obj != null)
-            {
                 beatmap.HitObjects.Add(obj);
-            }
         }
 
         private int getOffsetTime(int time) => time + (ApplyOffsets ? offset : 0);

osu.Game/Beatmaps/Formats/LegacyDecoder.cs

@@ -31,7 +31,7 @@ namespace osu.Game.Beatmaps.Formats
                 if (ShouldSkipLine(line))
                     continue;
 
-                if (line.StartsWith(@"[") && line.EndsWith(@"]"))
+                if (line.StartsWith(@"[", StringComparison.Ordinal) && line.EndsWith(@"]", StringComparison.Ordinal))
                 {
                     if (!Enum.TryParse(line.Substring(1, line.Length - 2), out section))
                     {
@@ -53,7 +53,7 @@ namespace osu.Game.Beatmaps.Formats
             }
         }
 
-        protected virtual bool ShouldSkipLine(string line) => string.IsNullOrWhiteSpace(line) || line.StartsWith("//");
+        protected virtual bool ShouldSkipLine(string line) => string.IsNullOrWhiteSpace(line) || line.StartsWith("//", StringComparison.Ordinal);
 
         protected virtual void ParseLine(T output, Section section, string line)
         {

osu.Game/Beatmaps/Formats/LegacyStoryboardDecoder.cs

@@ -60,7 +60,7 @@ namespace osu.Game.Beatmaps.Formats
         private void handleEvents(string line)
         {
             var depth = 0;
-            while (line.StartsWith(" ") || line.StartsWith("_"))
+            while (line.StartsWith(" ", StringComparison.Ordinal) || line.StartsWith("_", StringComparison.Ordinal))
             {
                 ++depth;
                 line = line.Substring(1);
@@ -269,9 +269,9 @@ namespace osu.Game.Beatmaps.Formats
                     return Anchor.BottomCentre;
                 case LegacyOrigins.BottomRight:
                     return Anchor.BottomRight;
+                default:
+                    return Anchor.TopLeft;
             }
-
-            throw new InvalidDataException($@"Unknown origin: {value}");
         }
 
         private void handleVariables(string line)

osu.Game/Beatmaps/WorkingBeatmap.cs

@@ -8,10 +8,10 @@ using osu.Game.Rulesets.Mods;
 using System;
 using System.Collections.Generic;
 using System.Linq;
-using System.Threading.Tasks;
 using osu.Game.Storyboards;
 using osu.Framework.IO.File;
 using System.IO;
+using System.Threading;
 using osu.Game.IO.Serialization;
 using osu.Game.Rulesets;
 using osu.Game.Rulesets.Objects;
@@ -38,12 +38,26 @@ namespace osu.Game.Beatmaps
 
             Mods.ValueChanged += mods => applyRateAdjustments();
 
-            beatmap = new AsyncLazy<IBeatmap>(populateBeatmap);
-            background = new AsyncLazy<Texture>(populateBackground, b => b == null || !b.IsDisposed);
-            track = new AsyncLazy<Track>(populateTrack);
-            waveform = new AsyncLazy<Waveform>(populateWaveform);
-            storyboard = new AsyncLazy<Storyboard>(populateStoryboard);
-            skin = new AsyncLazy<Skin>(populateSkin);
+            beatmap = new RecyclableLazy<IBeatmap>(() =>
+            {
+                var b = GetBeatmap() ?? new Beatmap();
+                // use the database-backed info.
+                b.BeatmapInfo = BeatmapInfo;
+                return b;
+            });
+
+            track = new RecyclableLazy<Track>(() =>
+            {
+                // we want to ensure that we always have a track, even if it's a fake one.
+                var t = GetTrack() ?? new VirtualBeatmapTrack(Beatmap);
+                applyRateAdjustments(t);
+                return t;
+            });
+
+            background = new RecyclableLazy<Texture>(GetBackground, BackgroundStillValid);
+            waveform = new RecyclableLazy<Waveform>(GetWaveform);
+            storyboard = new RecyclableLazy<Storyboard>(GetStoryboard);
+            skin = new RecyclableLazy<Skin>(GetSkin);
         }
 
         /// <summary>
@@ -58,28 +72,6 @@ namespace osu.Game.Beatmaps
             return path;
         }
 
-        protected abstract IBeatmap GetBeatmap();
-        protected abstract Texture GetBackground();
-        protected abstract Track GetTrack();
-        protected virtual Skin GetSkin() => new DefaultSkin();
-        protected virtual Waveform GetWaveform() => new Waveform();
-        protected virtual Storyboard GetStoryboard() => new Storyboard { BeatmapInfo = BeatmapInfo };
-
-        public bool BeatmapLoaded => beatmap.IsResultAvailable;
-        public IBeatmap Beatmap => beatmap.Value.Result;
-        public async Task<IBeatmap> GetBeatmapAsync() => await beatmap.Value;
-        private readonly AsyncLazy<IBeatmap> beatmap;
-
-        private IBeatmap populateBeatmap()
-        {
-            var b = GetBeatmap() ?? new Beatmap();
-
-            // use the database-backed info.
-            b.BeatmapInfo = BeatmapInfo;
-
-            return b;
-        }
-
         /// <summary>
         /// Constructs a playable <see cref="IBeatmap"/> from <see cref="Beatmap"/> using the applicable converters for a specific <see cref="RulesetInfo"/>.
         /// <para>
@@ -136,62 +128,53 @@ namespace osu.Game.Beatmaps
 
         public override string ToString() => BeatmapInfo.ToString();
 
-        public bool BackgroundLoaded => background.IsResultAvailable;
-        public Texture Background => background.Value.Result;
-        public async Task<Texture> GetBackgroundAsync() => await background.Value;
-        private AsyncLazy<Texture> background;
+        public bool BeatmapLoaded => beatmap.IsResultAvailable;
+        public IBeatmap Beatmap => beatmap.Value;
+        protected abstract IBeatmap GetBeatmap();
+        private readonly RecyclableLazy<IBeatmap> beatmap;
 
-        private Texture populateBackground() => GetBackground();
+        public bool BackgroundLoaded => background.IsResultAvailable;
+        public Texture Background => background.Value;
+        protected virtual bool BackgroundStillValid(Texture b) => b == null || !b.IsDisposed;
+        protected abstract Texture GetBackground();
+        private readonly RecyclableLazy<Texture> background;
 
         public bool TrackLoaded => track.IsResultAvailable;
-        public Track Track => track.Value.Result;
-        public async Task<Track> GetTrackAsync() => await track.Value;
-        private AsyncLazy<Track> track;
-
-        private Track populateTrack()
-        {
-            // we want to ensure that we always have a track, even if it's a fake one.
-            var t = GetTrack() ?? new VirtualBeatmapTrack(Beatmap);
-            applyRateAdjustments(t);
-            return t;
-        }
+        public Track Track => track.Value;
+        protected abstract Track GetTrack();
+        private RecyclableLazy<Track> track;
 
         public bool WaveformLoaded => waveform.IsResultAvailable;
-        public Waveform Waveform => waveform.Value.Result;
-        public async Task<Waveform> GetWaveformAsync() => await waveform.Value;
-        private readonly AsyncLazy<Waveform> waveform;
-
-        private Waveform populateWaveform() => GetWaveform();
+        public Waveform Waveform => waveform.Value;
+        protected virtual Waveform GetWaveform() => new Waveform();
+        private readonly RecyclableLazy<Waveform> waveform;
 
         public bool StoryboardLoaded => storyboard.IsResultAvailable;
-        public Storyboard Storyboard => storyboard.Value.Result;
-        public async Task<Storyboard> GetStoryboardAsync() => await storyboard.Value;
-        private readonly AsyncLazy<Storyboard> storyboard;
-
-        private Storyboard populateStoryboard() => GetStoryboard();
+        public Storyboard Storyboard => storyboard.Value;
+        protected virtual Storyboard GetStoryboard() => new Storyboard { BeatmapInfo = BeatmapInfo };
+        private readonly RecyclableLazy<Storyboard> storyboard;
 
         public bool SkinLoaded => skin.IsResultAvailable;
-        public Skin Skin => skin.Value.Result;
-        public async Task<Skin> GetSkinAsync() => await skin.Value;
-        private readonly AsyncLazy<Skin> skin;
+        public Skin Skin => skin.Value;
+        protected virtual Skin GetSkin() => new DefaultSkin();
+        private readonly RecyclableLazy<Skin> skin;
 
-        private Skin populateSkin() => GetSkin();
-
-        public void TransferTo(WorkingBeatmap other)
+        /// <summary>
+        /// Transfer pieces of a beatmap to a new one, where possible, to save on loading.
+        /// </summary>
+        /// <param name="other">The new beatmap which is being switched to.</param>
+        public virtual void TransferTo(WorkingBeatmap other)
         {
             if (track.IsResultAvailable && Track != null && BeatmapInfo.AudioEquals(other.BeatmapInfo))
                 other.track = track;
-
-            if (background.IsResultAvailable && Background != null && BeatmapInfo.BackgroundEquals(other.BeatmapInfo))
-                other.background = background;
         }
 
         public virtual void Dispose()
         {
-            if (BackgroundLoaded) Background?.Dispose();
-            if (WaveformLoaded) Waveform?.Dispose();
-            if (StoryboardLoaded) Storyboard?.Dispose();
-            if (SkinLoaded) Skin?.Dispose();
+            background.Recycle();
+            waveform.Recycle();
+            storyboard.Recycle();
+            skin.Recycle();
         }
 
         /// <summary>
@@ -210,15 +193,15 @@ namespace osu.Game.Beatmaps
                 mod.ApplyToClock(t);
         }
 
-        public class AsyncLazy<T>
+        public class RecyclableLazy<T>
         {
-            private Lazy<Task<T>> lazy;
+            private Lazy<T> lazy;
             private readonly Func<T> valueFactory;
             private readonly Func<T, bool> stillValidFunction;
 
-            private readonly object initLock = new object();
+            private readonly object fetchLock = new object();
 
-            public AsyncLazy(Func<T> valueFactory, Func<T, bool> stillValidFunction = null)
+            public RecyclableLazy(Func<T> valueFactory, Func<T, bool> stillValidFunction = null)
             {
                 this.valueFactory = valueFactory;
                 this.stillValidFunction = stillValidFunction;
@@ -230,45 +213,28 @@ namespace osu.Game.Beatmaps
             {
                 if (!IsResultAvailable) return;
 
-                (lazy.Value.Result as IDisposable)?.Dispose();
+                (lazy.Value as IDisposable)?.Dispose();
                 recreate();
             }
 
-            public bool IsResultAvailable
+            public bool IsResultAvailable => stillValid;
+
+            public T Value
             {
                 get
                 {
-                    recreateIfInvalid();
-                    return lazy.Value.IsCompleted;
+                    lock (fetchLock)
+                    {
+                        if (!stillValid)
+                            recreate();
+                        return lazy.Value;
+                    }
                 }
             }
 
-            public Task<T> Value
-            {
-                get
-                {
-                    recreateIfInvalid();
-                    return lazy.Value;
-                }
-            }
+            private bool stillValid => lazy.IsValueCreated && (stillValidFunction?.Invoke(lazy.Value) ?? true);
 
-            private void recreateIfInvalid()
-            {
-                lock (initLock)
-                {
-                    if (!lazy.IsValueCreated || !lazy.Value.IsCompleted)
-                        // we have not yet been initialised or haven't run the task.
-                        return;
-
-                    if (stillValidFunction?.Invoke(lazy.Value.Result) ?? true)
-                        // we are still in a valid state.
-                        return;
-
-                    recreate();
-                }
-            }
-
-            private void recreate() => lazy = new Lazy<Task<T>>(() => Task.Run(valueFactory));
+            private void recreate() => lazy = new Lazy<T>(valueFactory, LazyThreadSafetyMode.ExecutionAndPublication);
         }
     }
 }

osu.Game/Database/ArchiveModelManager.cs

@@ -5,6 +5,7 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
+using System.Threading.Tasks;
 using JetBrains.Annotations;
 using Microsoft.EntityFrameworkCore;
 using osu.Framework.IO.File;
@@ -129,7 +130,6 @@ namespace osu.Game.Database
             List<TModel> imported = new List<TModel>();
 
             int current = 0;
-            int errors = 0;
             foreach (string path in paths)
             {
                 if (notification.State == ProgressNotificationState.Cancelled)
@@ -162,12 +162,29 @@ namespace osu.Game.Database
                 {
                     e = e.InnerException ?? e;
                     Logger.Error(e, $@"Could not import ({Path.GetFileName(path)})");
-                    errors++;
                 }
             }
 
-            notification.Text = errors > 0 ? $"Import complete with {errors} errors" : "Import successful!";
-            notification.State = ProgressNotificationState.Completed;
+            if (imported.Count == 0)
+            {
+                notification.Text = "Import failed!";
+                notification.State = ProgressNotificationState.Cancelled;
+            }
+            else
+            {
+                notification.CompletionText = $"Imported {current} {typeof(TModel).Name.Replace("Info", "").ToLower()}s!";
+                notification.CompletionClickAction += () =>
+                {
+                    if (imported.Count > 0)
+                        PresentCompletedImport(imported);
+                    return true;
+                };
+                notification.State = ProgressNotificationState.Completed;
+            }
+        }
+
+        protected virtual void PresentCompletedImport(IEnumerable<TModel> imported)
+        {
         }
 
         /// <summary>
@@ -178,7 +195,8 @@ namespace osu.Game.Database
         {
             try
             {
-                return Import(CreateModel(archive), archive);
+                var model = CreateModel(archive);
+                return model == null ? null : Import(model, archive);
             }
             catch (Exception e)
             {
@@ -282,7 +300,7 @@ namespace osu.Game.Database
             var notification = new ProgressNotification
             {
                 Progress = 0,
-                CompletionText = "Deleted all beatmaps!",
+                CompletionText = $"Deleted all {typeof(TModel).Name.Replace("Info", "").ToLower()}s!",
                 State = ProgressNotificationState.Active,
             };
 
@@ -384,12 +402,47 @@ namespace osu.Game.Database
             return fileInfos;
         }
 
+        #region osu-stable import
+
+        /// <summary>
+        /// Set a storage with access to an osu-stable install for import purposes.
+        /// </summary>
+        public Func<Storage> GetStableStorage { private get; set; }
+
+        /// <summary>
+        /// Denotes whether an osu-stable installation is present to perform automated imports from.
+        /// </summary>
+        public bool StableInstallationAvailable => GetStableStorage?.Invoke() != null;
+
+        /// <summary>
+        /// The relative path from osu-stable's data directory to import items from.
+        /// </summary>
+        protected virtual string ImportFromStablePath => null;
+
+        /// <summary>
+        /// This is a temporary method and will likely be replaced by a full-fledged (and more correctly placed) migration process in the future.
+        /// </summary>
+        public Task ImportFromStableAsync()
+        {
+            var stable = GetStableStorage?.Invoke();
+
+            if (stable == null)
+            {
+                Logger.Log("No osu!stable installation available!", LoggingTarget.Information, LogLevel.Error);
+                return Task.CompletedTask;
+            }
+
+            return Task.Factory.StartNew(() => Import(stable.GetDirectories(ImportFromStablePath).Select(f => stable.GetFullPath(f)).ToArray()), TaskCreationOptions.LongRunning);
+        }
+
+        #endregion
+
         /// <summary>
         /// Create a barebones model from the provided archive.
         /// Actual expensive population should be done in <see cref="Populate"/>; this should just prepare for duplicate checking.
         /// </summary>
         /// <param name="archive">The archive to create the model for.</param>
-        /// <returns>A model populated with minimal information.</returns>
+        /// <returns>A model populated with minimal information. Returning a null will abort importing silently.</returns>
         protected abstract TModel CreateModel(ArchiveReader archive);
 
         /// <summary>

osu.Game/Database/DatabaseContextFactory.cs

@@ -5,7 +5,6 @@ using System;
 using System.Linq;
 using System.Threading;
 using Microsoft.EntityFrameworkCore.Storage;
-using osu.Framework.Extensions.IEnumerableExtensions;
 using osu.Framework.Platform;
 
 namespace osu.Game.Database
@@ -118,7 +117,9 @@ namespace osu.Game.Database
 
         private void recycleThreadContexts()
         {
-            threadContexts?.Values.ForEach(c => c.Dispose());
+            // Contexts for other threads are not disposed as they may be in use elsewhere. Instead, fresh contexts are exposed
+            // for other threads to use, and we rely on the finalizer inside OsuDbContext to handle their previous contexts
+            threadContexts?.Value.Dispose();
             threadContexts = new ThreadLocal<OsuDbContext>(CreateContext, true);
         }
 

osu.Game/Database/OsuDbContext.cs

@@ -75,6 +75,13 @@ namespace osu.Game.Database
             }
         }
 
+        ~OsuDbContext()
+        {
+            // DbContext does not contain a finalizer (https://github.com/aspnet/EntityFrameworkCore/issues/8872)
+            // This is used to clean up previous contexts when fresh contexts are exposed via DatabaseContextFactory
+            Dispose();
+        }
+
         protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
         {
             base.OnConfiguring(optionsBuilder);

osu.Game/Graphics/Backgrounds/Background.cs

@@ -5,8 +5,8 @@ using osu.Framework.Allocation;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Sprites;
+using osu.Framework.Graphics.Textures;
 using OpenTK.Graphics;
-using osu.Game.Graphics.Textures;
 
 namespace osu.Game.Graphics.Backgrounds
 {

osu.Game/Graphics/Backgrounds/Triangles.cs

@@ -116,7 +116,7 @@ namespace osu.Game.Graphics.Backgrounds
 
             float adjustedAlpha = HideAlphaDiscrepancies ?
                 // Cubically scale alpha to make it drop off more sharply.
-                (float)Math.Pow(DrawInfo.Colour.AverageColour.Linear.A, 3) :
+                (float)Math.Pow(DrawColourInfo.Colour.AverageColour.Linear.A, 3) :
                 1;
 
             float elapsedSeconds = (float)Time.Elapsed / 1000;
@@ -235,7 +235,7 @@ namespace osu.Game.Graphics.Backgrounds
                         Vector2Extensions.Transform(particle.Position * Size + new Vector2(-offset.X, offset.Y), DrawInfo.Matrix)
                     );
 
-                    ColourInfo colourInfo = DrawInfo.Colour;
+                    ColourInfo colourInfo = DrawColourInfo.Colour;
                     colourInfo.ApplyChild(particle.Colour);
 
                     Texture.DrawTriangle(

osu.Game/Graphics/Containers/ShakeContainer.cs

@@ -0,0 +1,39 @@
+// Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
+// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
+
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers;
+
+namespace osu.Game.Graphics.Containers
+{
+    /// <summary>
+    /// A container that adds the ability to shake its contents.
+    /// </summary>
+    public class ShakeContainer : Container
+    {
+        /// <summary>
+        /// Shake the contents of this container.
+        /// </summary>
+        /// <param name="maximumLength">The maximum length the shake should last.</param>
+        public void Shake(double maximumLength)
+        {
+            const float shake_amount = 8;
+            const float shake_duration = 30;
+
+            // if we don't have enough time, don't bother shaking.
+            if (maximumLength < shake_duration * 2)
+                return;
+
+            var sequence = this.MoveToX(shake_amount, shake_duration / 2, Easing.OutSine).Then()
+                               .MoveToX(-shake_amount, shake_duration, Easing.InOutSine).Then();
+
+            // if we don't have enough time for the second shake, skip it.
+            if (maximumLength > shake_duration * 4)
+                sequence = sequence
+                           .MoveToX(shake_amount, shake_duration, Easing.InOutSine).Then()
+                           .MoveToX(-shake_amount, shake_duration, Easing.InOutSine).Then();
+
+            sequence.MoveToX(0, shake_duration / 2, Easing.InSine);
+        }
+    }
+}

osu.Game/Graphics/DrawableDate.cs

@@ -4,7 +4,6 @@
 using System;
 using Humanizer;
 using osu.Framework.Allocation;
-using osu.Framework.Graphics;
 using osu.Framework.Graphics.Cursor;
 using osu.Game.Graphics.Sprites;
 
@@ -16,7 +15,6 @@ namespace osu.Game.Graphics
 
         public DrawableDate(DateTimeOffset date)
         {
-            AutoSizeAxes = Axes.Both;
             Font = "Exo2.0-RegularItalic";
 
             Date = date.ToLocalTime();

osu.Game/Graphics/ScreenshotManager.cs

@@ -71,7 +71,7 @@ namespace osu.Game.Graphics
 
         private volatile int screenShotTasks;
 
-        public async Task TakeScreenshotAsync() => await Task.Run(async () =>
+        public Task TakeScreenshotAsync() => Task.Run(async () =>
         {
             Interlocked.Increment(ref screenShotTasks);
 

osu.Game/Graphics/SpriteIcon.cs

@@ -71,7 +71,7 @@ namespace osu.Game.Graphics
 
             if (loadableIcon == loadedIcon) return;
 
-            var texture = store?.Get(((char)loadableIcon).ToString());
+            var texture = store.Get(((char)loadableIcon).ToString());
 
             spriteMain.Texture = texture;
             spriteShadow.Texture = texture;
@@ -95,7 +95,7 @@ namespace osu.Game.Graphics
             {
                 //adjust shadow alpha based on highest component intensity to avoid muddy display of darker text.
                 //squared result for quadratic fall-off seems to give the best result.
-                var avgColour = (Color4)DrawInfo.Colour.AverageColour;
+                var avgColour = (Color4)DrawColourInfo.Colour.AverageColour;
 
                 spriteShadow.Alpha = (float)Math.Pow(Math.Max(Math.Max(avgColour.R, avgColour.G), avgColour.B), 2);
 
@@ -129,7 +129,7 @@ namespace osu.Game.Graphics
                 if (icon == value) return;
 
                 icon = value;
-                if (IsLoaded)
+                if (LoadState == LoadState.Loaded)
                     updateTexture();
             }
         }

osu.Game/Graphics/Sprites/OsuSpriteText.cs

@@ -3,9 +3,6 @@
 
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Sprites;
-using osu.Framework.MathUtils;
-using OpenTK;
-using OpenTK.Graphics;
 using osu.Framework.Graphics.Transforms;
 
 namespace osu.Game.Graphics.Sprites
@@ -19,27 +16,6 @@ namespace osu.Game.Graphics.Sprites
             Shadow = true;
             TextSize = FONT_SIZE;
         }
-
-        protected override Drawable CreateFallbackCharacterDrawable()
-        {
-            var tex = GetTextureForCharacter('?');
-
-            if (tex != null)
-            {
-                float adjust = (RNG.NextSingle() - 0.5f) * 2;
-                return new Sprite
-                {
-                    Texture = tex,
-                    Origin = Anchor.Centre,
-                    Anchor = Anchor.Centre,
-                    Scale = new Vector2(1 + adjust * 0.2f),
-                    Rotation = adjust * 15,
-                    Colour = Color4.White,
-                };
-            }
-
-            return base.CreateFallbackCharacterDrawable();
-        }
     }
 
     public static class OsuSpriteTextTransformExtensions

osu.Game/Graphics/Textures/LargeTextureStore.cs

@@ -1,18 +0,0 @@
-// Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
-// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
-
-using osu.Framework.Graphics.Textures;
-using osu.Framework.IO.Stores;
-
-namespace osu.Game.Graphics.Textures
-{
-    /// <summary>
-    /// A texture store that bypasses atlasing.
-    /// </summary>
-    public class LargeTextureStore : TextureStore
-    {
-        public LargeTextureStore(IResourceStore<RawTexture> store = null) : base(store, false)
-        {
-        }
-    }
-}

osu.Game/Graphics/UserInterface/OsuButton.cs

@@ -1,7 +1,16 @@
 // Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
+using osu.Framework.Allocation;
+using osu.Framework.Extensions.Color4Extensions;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Shapes;
+using osu.Framework.Graphics.Sprites;
 using osu.Framework.Graphics.UserInterface;
+using osu.Framework.Input.EventArgs;
+using osu.Framework.Input.States;
+using osu.Game.Graphics.Sprites;
+using OpenTK.Graphics;
 
 namespace osu.Game.Graphics.UserInterface
 {
@@ -10,9 +19,73 @@ namespace osu.Game.Graphics.UserInterface
     /// </summary>
     public class OsuButton : Button
     {
+        private Box hover;
+
         public OsuButton()
         {
-            Add(new HoverClickSounds(HoverSampleSet.Loud));
+            Height = 40;
+
+            Content.Masking = true;
+            Content.CornerRadius = 5;
         }
+
+        [BackgroundDependencyLoader]
+        private void load(OsuColour colours)
+        {
+            BackgroundColour = colours.BlueDark;
+
+            AddRange(new Drawable[]
+            {
+                hover = new Box
+                {
+                    RelativeSizeAxes = Axes.Both,
+                    Blending = BlendingMode.Additive,
+                    Colour = Color4.White.Opacity(0.1f),
+                    Alpha = 0,
+                    Depth = -1
+                },
+                new HoverClickSounds(HoverSampleSet.Loud),
+            });
+
+            Enabled.ValueChanged += enabled_ValueChanged;
+            Enabled.TriggerChange();
+        }
+
+        private void enabled_ValueChanged(bool enabled)
+        {
+            this.FadeColour(enabled ? Color4.White : Color4.Gray, 200, Easing.OutQuint);
+        }
+
+        protected override bool OnHover(InputState state)
+        {
+            hover.FadeIn(200);
+            return base.OnHover(state);
+        }
+
+        protected override void OnHoverLost(InputState state)
+        {
+            hover.FadeOut(200);
+            base.OnHoverLost(state);
+        }
+
+        protected override bool OnMouseDown(InputState state, MouseDownEventArgs args)
+        {
+            Content.ScaleTo(0.9f, 4000, Easing.OutQuint);
+            return base.OnMouseDown(state, args);
+        }
+
+        protected override bool OnMouseUp(InputState state, MouseUpEventArgs args)
+        {
+            Content.ScaleTo(1, 1000, Easing.OutElastic);
+            return base.OnMouseUp(state, args);
+        }
+
+        protected override SpriteText CreateText() => new OsuSpriteText
+        {
+            Depth = -1,
+            Origin = Anchor.Centre,
+            Anchor = Anchor.Centre,
+            Font = @"Exo2.0-Bold",
+        };
     }
 }

osu.Game/Graphics/UserInterface/TriangleButton.cs

@@ -2,17 +2,10 @@
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
 using System.Collections.Generic;
-using OpenTK.Graphics;
 using osu.Framework.Allocation;
-using osu.Framework.Extensions.Color4Extensions;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
-using osu.Framework.Graphics.Shapes;
-using osu.Framework.Graphics.Sprites;
-using osu.Framework.Input.EventArgs;
-using osu.Framework.Input.States;
 using osu.Game.Graphics.Backgrounds;
-using osu.Game.Graphics.Sprites;
 
 namespace osu.Game.Graphics.UserInterface
 {
@@ -21,79 +14,17 @@ namespace osu.Game.Graphics.UserInterface
     /// </summary>
     public class TriangleButton : OsuButton, IFilterable
     {
-        private Box hover;
-
-        protected Triangles Triangles;
-
-        public TriangleButton()
-        {
-            Height = 40;
-        }
-
-        protected override SpriteText CreateText() => new OsuSpriteText
-        {
-            Depth = -1,
-            Origin = Anchor.Centre,
-            Anchor = Anchor.Centre,
-            Font = @"Exo2.0-Bold",
-        };
+        protected Triangles Triangles { get; private set; }
 
         [BackgroundDependencyLoader]
         private void load(OsuColour colours)
         {
-            BackgroundColour = colours.BlueDark;
-
-            Content.Masking = true;
-            Content.CornerRadius = 5;
-
-            AddRange(new Drawable[]
+            Add(Triangles = new Triangles
             {
-                Triangles = new Triangles
-                {
-                    RelativeSizeAxes = Axes.Both,
-                    ColourDark = colours.BlueDarker,
-                    ColourLight = colours.Blue,
-                },
-                hover = new Box
-                {
-                    RelativeSizeAxes = Axes.Both,
-                    Blending = BlendingMode.Additive,
-                    Colour = Color4.White.Opacity(0.1f),
-                    Alpha = 0,
-                },
+                RelativeSizeAxes = Axes.Both,
+                ColourDark = colours.BlueDarker,
+                ColourLight = colours.Blue,
             });
-
-            Enabled.ValueChanged += enabled_ValueChanged;
-            Enabled.TriggerChange();
-        }
-
-        private void enabled_ValueChanged(bool enabled)
-        {
-            this.FadeColour(enabled ? Color4.White : Color4.Gray, 200, Easing.OutQuint);
-        }
-
-        protected override bool OnHover(InputState state)
-        {
-            hover.FadeIn(200);
-            return base.OnHover(state);
-        }
-
-        protected override void OnHoverLost(InputState state)
-        {
-            hover.FadeOut(200);
-            base.OnHoverLost(state);
-        }
-
-        protected override bool OnMouseDown(InputState state, MouseDownEventArgs args)
-        {
-            Content.ScaleTo(0.9f, 4000, Easing.OutQuint);
-            return base.OnMouseDown(state, args);
-        }
-
-        protected override bool OnMouseUp(InputState state, MouseUpEventArgs args)
-        {
-            Content.ScaleTo(1, 1000, Easing.OutElastic);
-            return base.OnMouseUp(state, args);
         }
 
         public IEnumerable<string> FilterTerms => new[] { Text };

osu.Game/IO/Archives/ArchiveReader.cs

@@ -3,6 +3,7 @@
 
 using System.Collections.Generic;
 using System.IO;
+using System.Threading.Tasks;
 using osu.Framework.IO.Stores;
 
 namespace osu.Game.IO.Archives
@@ -28,7 +29,9 @@ namespace osu.Game.IO.Archives
 
         public abstract IEnumerable<string> Filenames { get; }
 
-        public virtual byte[] Get(string name)
+        public virtual byte[] Get(string name) => GetAsync(name).Result;
+
+        public async Task<byte[]> GetAsync(string name)
         {
             using (Stream input = GetStream(name))
             {
@@ -36,7 +39,7 @@ namespace osu.Game.IO.Archives
                     return null;
 
                 byte[] buffer = new byte[input.Length];
-                input.Read(buffer, 0, buffer.Length);
+                await input.ReadAsync(buffer, 0, buffer.Length);
                 return buffer;
             }
         }

osu.Game/Online/API/APIAccess.cs

@@ -2,12 +2,10 @@
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
 using System;
-using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Net;
 using System.Threading;
-using System.Threading.Tasks;
 using osu.Framework.Configuration;
 using osu.Framework.Graphics;
 using osu.Framework.Logging;
@@ -26,7 +24,7 @@ namespace osu.Game.Online.API
         private const string client_id = @"5";
         private const string client_secret = @"FGc9GAtyHzeQDshWP5Ah7dega8hJACAJpQtw6OXk";
 
-        private ConcurrentQueue<APIRequest> queue = new ConcurrentQueue<APIRequest>();
+        private readonly Queue<APIRequest> queue = new Queue<APIRequest>();
 
         /// <summary>
         /// The username/email provided by the user when initiating a login.
@@ -55,7 +53,13 @@ namespace osu.Game.Online.API
             authentication.TokenString = config.Get<string>(OsuSetting.Token);
             authentication.Token.ValueChanged += onTokenChanged;
 
-            Task.Factory.StartNew(run, cancellationToken.Token, TaskCreationOptions.LongRunning, TaskScheduler.Default);
+            var thread = new Thread(run)
+            {
+                Name = "APIAccess",
+                IsBackground = true
+            };
+
+            thread.Start();
         }
 
         private void onTokenChanged(OAuthToken token) => config.Set(OsuSetting.Token, config.Get<bool>(OsuSetting.SavePassword) ? authentication.TokenString : string.Empty);
@@ -75,10 +79,7 @@ namespace osu.Game.Online.API
 
         public void Unregister(IOnlineComponent component)
         {
-            Scheduler.Add(delegate
-            {
-                components.Remove(component);
-            });
+            Scheduler.Add(delegate { components.Remove(component); });
         }
 
         public string AccessToken => authentication.RequestAccessToken();
@@ -103,6 +104,7 @@ namespace osu.Game.Online.API
                             log.Add(@"Queueing a ping request");
                             Queue(new ListChannelsRequest { Timeout = 5000 });
                         }
+
                         break;
                     case APIState.Offline:
                     case APIState.Connecting:
@@ -161,18 +163,21 @@ namespace osu.Game.Online.API
                     continue;
                 }
 
-                //process the request queue.
-                APIRequest req;
-                while (queue.TryPeek(out req))
+                while (true)
                 {
-                    if (handleRequest(req))
+                    APIRequest req;
+
+                    lock (queue)
                     {
-                        //we have succeeded, so let's unqueue.
-                        queue.TryDequeue(out req);
+                        if (queue.Count == 0) break;
+                        req = queue.Dequeue();
                     }
+
+                    // TODO: handle failures better
+                    handleRequest(req);
                 }
 
-                Thread.Sleep(1);
+                Thread.Sleep(50);
             }
         }
 
@@ -205,7 +210,8 @@ namespace osu.Game.Online.API
             }
             catch (WebException we)
             {
-                HttpStatusCode statusCode = (we.Response as HttpWebResponse)?.StatusCode ?? (we.Status == WebExceptionStatus.UnknownError ? HttpStatusCode.NotAcceptable : HttpStatusCode.RequestTimeout);
+                HttpStatusCode statusCode = (we.Response as HttpWebResponse)?.StatusCode
+                                            ?? (we.Status == WebExceptionStatus.UnknownError ? HttpStatusCode.NotAcceptable : HttpStatusCode.RequestTimeout);
 
                 // special cases for un-typed but useful message responses.
                 switch (we.Message)
@@ -247,6 +253,7 @@ namespace osu.Game.Online.API
         }
 
         private APIState state;
+
         public APIState State
         {
             get { return state; }
@@ -271,7 +278,10 @@ namespace osu.Game.Online.API
 
         public bool IsLoggedIn => LocalUser.Value.Id > 1;
 
-        public void Queue(APIRequest request) => queue.Enqueue(request);
+        public void Queue(APIRequest request)
+        {
+            lock (queue) queue.Enqueue(request);
+        }
 
         public event StateChangeDelegate OnStateChange;
 
@@ -279,16 +289,17 @@ namespace osu.Game.Online.API
 
         private void flushQueue(bool failOldRequests = true)
         {
-            var oldQueue = queue;
-
-            //flush the queue.
-            queue = new ConcurrentQueue<APIRequest>();
-
-            if (failOldRequests)
+            lock (queue)
             {
-                APIRequest req;
-                while (oldQueue.TryDequeue(out req))
-                    req.Fail(new WebException(@"Disconnected from server"));
+                var oldQueueRequests = queue.ToArray();
+
+                queue.Clear();
+
+                if (failOldRequests)
+                {
+                    foreach (var req in oldQueueRequests)
+                        req.Fail(new WebException(@"Disconnected from server"));
+                }
             }
         }
 

osu.Game/OsuGame.cs

@@ -75,10 +75,10 @@ namespace osu.Game
         {
             get
             {
-                Screen s = screenStack;
-                while (s != null && !(s is Intro))
-                    s = s.ChildScreen;
-                return s as Intro;
+                Screen screen = screenStack;
+                while (screen != null && !(screen is Intro))
+                    screen = screen.ChildScreen;
+                return screen as Intro;
             }
         }
 
@@ -126,8 +126,8 @@ namespace osu.Game
         /// <param name="toolbar">Whether the toolbar should also be hidden.</param>
         public void CloseAllOverlays(bool toolbar = true)
         {
-            foreach (var o in overlays)
-                o.State = Visibility.Hidden;
+            foreach (var overlay in overlays)
+                overlay.State = Visibility.Hidden;
             if (toolbar) Toolbar.State = Visibility.Hidden;
         }
 
@@ -244,7 +244,7 @@ namespace osu.Game
         /// <param name="beatmapId">The beatmap to show.</param>
         public void ShowBeatmap(int beatmapId) => beatmapSetOverlay.FetchAndShowBeatmap(beatmapId);
 
-        protected void LoadScore(Score s)
+        protected void LoadScore(Score score)
         {
             scoreLoad?.Cancel();
 
@@ -252,18 +252,18 @@ namespace osu.Game
 
             if (menu == null)
             {
-                scoreLoad = Schedule(() => LoadScore(s));
+                scoreLoad = Schedule(() => LoadScore(score));
                 return;
             }
 
             if (!menu.IsCurrentScreen)
             {
                 menu.MakeCurrent();
-                this.Delay(500).Schedule(() => LoadScore(s), out scoreLoad);
+                this.Delay(500).Schedule(() => LoadScore(score), out scoreLoad);
                 return;
             }
 
-            if (s.Beatmap == null)
+            if (score.Beatmap == null)
             {
                 notifications.Post(new SimpleNotification
                 {
@@ -273,12 +273,12 @@ namespace osu.Game
                 return;
             }
 
-            ruleset.Value = s.Ruleset;
+            ruleset.Value = score.Ruleset;
 
-            Beatmap.Value = BeatmapManager.GetWorkingBeatmap(s.Beatmap);
-            Beatmap.Value.Mods.Value = s.Mods;
+            Beatmap.Value = BeatmapManager.GetWorkingBeatmap(score.Beatmap);
+            Beatmap.Value.Mods.Value = score.Mods;
 
-            menu.Push(new PlayerLoader(new ReplayPlayer(s.Replay)));
+            menu.Push(new PlayerLoader(new ReplayPlayer(score.Replay)));
         }
 
         protected override void Dispose(bool isDisposing)
@@ -299,11 +299,13 @@ namespace osu.Game
             // This prevents the cursor from showing until we have a screen with CursorVisible = true
             MenuCursorContainer.CanShowCursor = currentScreen?.CursorVisible ?? false;
 
-            // hook up notifications to components.
+            // todo: all archive managers should be able to be looped here.
             SkinManager.PostNotification = n => notifications?.Post(n);
-            BeatmapManager.PostNotification = n => notifications?.Post(n);
+            SkinManager.GetStableStorage = GetStorageForStableInstall;
 
+            BeatmapManager.PostNotification = n => notifications?.Post(n);
             BeatmapManager.GetStableStorage = GetStorageForStableInstall;
+
             BeatmapManager.PresentBeatmap = PresentBeatmap;
 
             AddRange(new Drawable[]
@@ -504,7 +506,27 @@ namespace osu.Game
             // schedule is here to ensure that all component loads are done after LoadComplete is run (and thus all dependencies are cached).
             // with some better organisation of LoadComplete to do construction and dependency caching in one step, followed by calls to loadComponentSingleFile,
             // we could avoid the need for scheduling altogether.
-            Schedule(() => { asyncLoadStream = asyncLoadStream?.ContinueWith(t => LoadComponentAsync(d, add).Wait()) ?? LoadComponentAsync(d, add); });
+            Schedule(() =>
+            {
+                var previousLoadStream = asyncLoadStream;
+
+                //chain with existing load stream
+                asyncLoadStream = Task.Run(async () =>
+                {
+                    if (previousLoadStream != null)
+                        await previousLoadStream;
+
+                    try
+                    {
+                        Logger.Log($"Loading {d}...", LoggingTarget.Debug);
+                        await LoadComponentAsync(d, add);
+                        Logger.Log($"Loaded {d}!", LoggingTarget.Debug);
+                    }
+                    catch (OperationCanceledException)
+                    {
+                    }
+                });
+            });
         }
 
         public bool OnPressed(GlobalAction action)

osu.Game/OsuGameBase.cs

@@ -24,7 +24,6 @@ using osu.Framework.Input;
 using osu.Framework.Logging;
 using osu.Game.Audio;
 using osu.Game.Database;
-using osu.Game.Graphics.Textures;
 using osu.Game.Input;
 using osu.Game.Input.Bindings;
 using osu.Game.IO;
@@ -109,11 +108,39 @@ namespace osu.Game
 
             dependencies.Cache(contextFactory = new DatabaseContextFactory(Host.Storage));
 
-            dependencies.Cache(new LargeTextureStore(new RawTextureLoaderStore(new NamespacedResourceStore<byte[]>(Resources, @"Textures"))));
+            var largeStore = new LargeTextureStore(new TextureLoaderStore(new NamespacedResourceStore<byte[]>(Resources, @"Textures")));
+            largeStore.AddStore(new TextureLoaderStore(new OnlineStore()));
+            dependencies.Cache(largeStore);
 
             dependencies.CacheAs(this);
             dependencies.Cache(LocalConfig);
 
+            //this completely overrides the framework default. will need to change once we make a proper FontStore.
+            dependencies.Cache(Fonts = new FontStore(new GlyphStore(Resources, @"Fonts/FontAwesome")));
+
+            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/osuFont"));
+            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-Medium"));
+            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-MediumItalic"));
+
+            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Noto-Basic"));
+            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Noto-Hangul"));
+            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Noto-CJK-Basic"));
+            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Noto-CJK-Compatibility"));
+
+            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-Regular"));
+            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-RegularItalic"));
+            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-SemiBold"));
+            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-SemiBoldItalic"));
+            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-Bold"));
+            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-BoldItalic"));
+            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-Light"));
+            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-LightItalic"));
+            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-Black"));
+            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-BlackItalic"));
+
+            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Venera"));
+            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Venera-Light"));
+
             runMigrations();
 
             dependencies.Cache(SkinManager = new SkinManager(Host.Storage, contextFactory, Host, Audio));
@@ -137,33 +164,6 @@ namespace osu.Game
             fileImporters.Add(ScoreStore);
             fileImporters.Add(SkinManager);
 
-            //this completely overrides the framework default. will need to change once we make a proper FontStore.
-            dependencies.Cache(Fonts = new FontStore { ScaleAdjust = 100 });
-
-            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/FontAwesome"));
-            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/osuFont"));
-            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-Medium"));
-            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-MediumItalic"));
-
-            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Noto-Basic"));
-            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Noto-Hangul"));
-            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Noto-CJK-Basic"));
-            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Noto-CJK-Compatibility"));
-
-            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-Regular"));
-            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-RegularItalic"));
-            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-SemiBold"));
-            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-SemiBoldItalic"));
-            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-Bold"));
-            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-BoldItalic"));
-            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-Light"));
-            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-LightItalic"));
-            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-Black"));
-            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Exo2.0-BlackItalic"));
-
-            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Venera"));
-            Fonts.AddStore(new GlyphStore(Resources, @"Fonts/Venera-Light"));
-
             var defaultBeatmap = new DummyWorkingBeatmap(this);
             beatmap = new OsuBindableBeatmap(defaultBeatmap, Audio);
             BeatmapManager.DefaultBeatmap = defaultBeatmap;

osu.Game/Overlays/BeatmapSet/Scores/ScoresContainer.cs

@@ -62,7 +62,7 @@ namespace osu.Game.Overlays.BeatmapSet.Scores
                 loading = true;
 
                 getScoresRequest = new GetScoresRequest(beatmap, beatmap.Ruleset);
-                getScoresRequest.Success += r => Scores = r.Scores;
+                getScoresRequest.Success += r => Schedule(() => Scores = r.Scores);
                 api.Queue(getScoresRequest);
             }
         }
@@ -134,5 +134,10 @@ namespace osu.Game.Overlays.BeatmapSet.Scores
             this.api = api;
             updateDisplay();
         }
+
+        protected override void Dispose(bool isDisposing)
+        {
+            getScoresRequest?.Cancel();
+        }
     }
 }

osu.Game/Overlays/Direct/DirectPanel.cs

@@ -104,8 +104,6 @@ namespace osu.Game.Overlays.Direct
             beatmaps.ItemAdded += setAdded;
         }
 
-        public override bool DisposeOnDeathRemoval => true;
-
         protected override void Dispose(bool isDisposing)
         {
             base.Dispose(isDisposing);
@@ -187,7 +185,7 @@ namespace osu.Game.Overlays.Direct
             base.LoadComplete();
             this.FadeInFromZero(200, Easing.Out);
 
-            PreviewPlaying.ValueChanged += newValue => PlayButton.FadeTo(newValue || IsHovered ? 1 : 0, 120, Easing.InOutQuint);
+            PreviewPlaying.ValueChanged += newValue => PlayButton.FadeTo(newValue || IsHovered || !FadePlayButton ? 1 : 0, 120, Easing.InOutQuint);
             PreviewPlaying.ValueChanged += newValue => PreviewBar.FadeTo(newValue ? 1 : 0, 120, Easing.InOutQuint);
         }
 

osu.Game/Overlays/DirectOverlay.cs

@@ -240,6 +240,15 @@ namespace osu.Game.Overlays
             });
         }
 
+        protected override void PopIn()
+        {
+            base.PopIn();
+
+            // Queries are allowed to be run only on the first pop-in
+            if (getSetsRequest == null)
+                Scheduler.AddOnce(updateSearch);
+        }
+
         private SearchBeatmapSetsRequest getSetsRequest;
 
         private readonly Bindable<string> currentQuery = new Bindable<string>();
@@ -251,16 +260,22 @@ namespace osu.Game.Overlays
         {
             queryChangedDebounce?.Cancel();
 
-            if (!IsLoaded) return;
+            if (!IsLoaded)
+                return;
+
+            if (State == Visibility.Hidden)
+                return;
 
             BeatmapSets = null;
             ResultAmounts = null;
 
             getSetsRequest?.Cancel();
 
-            if (api == null) return;
+            if (api == null)
+                return;
 
-            if (Header.Tabs.Current.Value == DirectTab.Search && (Filter.Search.Text == string.Empty || currentQuery == string.Empty)) return;
+            if (Header.Tabs.Current.Value == DirectTab.Search && (Filter.Search.Text == string.Empty || currentQuery == string.Empty))
+                return;
 
             previewTrackManager.StopAnyPlaying(this);
 

osu.Game/Overlays/MedalSplash/DrawableMedal.cs

@@ -118,9 +118,9 @@ namespace osu.Game.Overlays.MedalSplash
         }
 
         [BackgroundDependencyLoader]
-        private void load(OsuColour colours, TextureStore textures)
+        private void load(OsuColour colours, TextureStore textures, LargeTextureStore largeTextures)
         {
-            medalSprite.Texture = textures.Get(medal.ImageUrl);
+            medalSprite.Texture = largeTextures.Get(medal.ImageUrl);
             medalGlow.Texture = textures.Get(@"MedalSplash/medal-glow");
             description.Colour = colours.BlueLight;
         }

osu.Game/Overlays/NotificationOverlay.cs

@@ -96,8 +96,7 @@ namespace osu.Game.Overlays
             base.LoadComplete();
 
             StateChanged += _ => updateProcessingMode();
-            OverlayActivationMode.ValueChanged += _ => updateProcessingMode();
-            OverlayActivationMode.TriggerChange();
+            OverlayActivationMode.BindValueChanged(_ => updateProcessingMode(), true);
         }
 
         private int totalCount => sections.Select(c => c.DisplayedCount).Sum();

osu.Game/Overlays/Notifications/ProgressNotification.cs

@@ -169,7 +169,7 @@ namespace osu.Game.Overlays.Notifications
         public Action<Notification> CompletionTarget { get; set; }
 
         /// <summary>
-        /// An action to complete when the completion notification is clicked.
+        /// An action to complete when the completion notification is clicked. Return true to close.
         /// </summary>
         public Func<bool> CompletionClickAction;
 

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

@@ -176,7 +176,7 @@ namespace osu.Game.Overlays.Profile.Header
             }
 
             [BackgroundDependencyLoader]
-            private void load(TextureStore textures)
+            private void load(LargeTextureStore textures)
             {
                 Child = new Sprite
                 {

osu.Game/Overlays/Profile/Sections/Beatmaps/PaginatedBeatmapContainer.cs

@@ -14,8 +14,8 @@ namespace osu.Game.Overlays.Profile.Sections.Beatmaps
     public class PaginatedBeatmapContainer : PaginatedContainer
     {
         private const float panel_padding = 10f;
-
         private readonly BeatmapSetType type;
+        private GetUserBeatmapsRequest request;
 
         public PaginatedBeatmapContainer(BeatmapSetType type, Bindable<User> user, string header, string missing = "None... yet.")
             : base(user, header, missing)
@@ -31,9 +31,8 @@ namespace osu.Game.Overlays.Profile.Sections.Beatmaps
         {
             base.ShowMore();
 
-            var req = new GetUserBeatmapsRequest(User.Value.Id, type, VisiblePages++ * ItemsPerPage);
-
-            req.Success += sets =>
+            request = new GetUserBeatmapsRequest(User.Value.Id, type, VisiblePages++ * ItemsPerPage);
+            request.Success += sets => Schedule(() =>
             {
                 ShowMoreButton.FadeTo(sets.Count == ItemsPerPage ? 1 : 0);
                 ShowMoreLoading.Hide();
@@ -52,9 +51,15 @@ namespace osu.Game.Overlays.Profile.Sections.Beatmaps
                     var panel = new DirectGridPanel(s.ToBeatmapSet(Rulesets));
                     ItemsContainer.Add(panel);
                 }
-            };
+            });
 
-            Api.Queue(req);
+            Api.Queue(request);
+        }
+
+        protected override void Dispose(bool isDisposing)
+        {
+            base.Dispose(isDisposing);
+            request?.Cancel();
         }
     }
 }

osu.Game/Overlays/Profile/Sections/Historical/PaginatedMostPlayedBeatmapContainer.cs

@@ -12,6 +12,8 @@ namespace osu.Game.Overlays.Profile.Sections.Historical
 {
     public class PaginatedMostPlayedBeatmapContainer : PaginatedContainer
     {
+        private GetUserMostPlayedBeatmapsRequest request;
+
         public PaginatedMostPlayedBeatmapContainer(Bindable<User> user)
             :base(user, "Most Played Beatmaps", "No records. :(")
         {
@@ -24,9 +26,8 @@ namespace osu.Game.Overlays.Profile.Sections.Historical
         {
             base.ShowMore();
 
-            var req = new GetUserMostPlayedBeatmapsRequest(User.Value.Id, VisiblePages++ * ItemsPerPage);
-
-            req.Success += beatmaps =>
+            request = new GetUserMostPlayedBeatmapsRequest(User.Value.Id, VisiblePages++ * ItemsPerPage);
+            request.Success += beatmaps => Schedule(() =>
             {
                 ShowMoreButton.FadeTo(beatmaps.Count == ItemsPerPage ? 1 : 0);
                 ShowMoreLoading.Hide();
@@ -43,9 +44,16 @@ namespace osu.Game.Overlays.Profile.Sections.Historical
                 {
                     ItemsContainer.Add(new DrawableMostPlayedRow(beatmap.GetBeatmapInfo(Rulesets), beatmap.PlayCount));
                 }
-            };
+            });
 
-            Api.Queue(req);
+            Api.Queue(request);
+        }
+
+
+        protected override void Dispose(bool isDisposing)
+        {
+            base.Dispose(isDisposing);
+            request?.Cancel();
         }
     }
 }

osu.Game/Overlays/Profile/Sections/PaginatedContainer.cs

@@ -28,6 +28,7 @@ namespace osu.Game.Overlays.Profile.Sections
         protected readonly Bindable<User> User = new Bindable<User>();
 
         protected APIAccess Api;
+        protected APIRequest RetrievalRequest;
         protected RulesetStore Rulesets;
 
         public PaginatedContainer(Bindable<User> user, string header, string missing)

osu.Game/Overlays/Profile/Sections/Ranks/PaginatedScoreContainer.cs

@@ -16,6 +16,7 @@ namespace osu.Game.Overlays.Profile.Sections.Ranks
     {
         private readonly bool includeWeight;
         private readonly ScoreType type;
+        private GetUserScoresRequest request;
 
         public PaginatedScoreContainer(ScoreType type, Bindable<User> user, string header, string missing, bool includeWeight = false)
             : base(user, header, missing)
@@ -32,9 +33,8 @@ namespace osu.Game.Overlays.Profile.Sections.Ranks
         {
             base.ShowMore();
 
-            var req = new GetUserScoresRequest(User.Value.Id, type, VisiblePages++ * ItemsPerPage);
-
-            req.Success += scores =>
+            request = new GetUserScoresRequest(User.Value.Id, type, VisiblePages++ * ItemsPerPage);
+            request.Success += scores => Schedule(() =>
             {
                 foreach (var s in scores)
                     s.ApplyRuleset(Rulesets.GetRuleset(s.OnlineRulesetID));
@@ -66,9 +66,15 @@ namespace osu.Game.Overlays.Profile.Sections.Ranks
 
                     ItemsContainer.Add(drawableScore);
                 }
-            };
+            });
 
-            Api.Queue(req);
+            Api.Queue(request);
+        }
+
+        protected override void Dispose(bool isDisposing)
+        {
+            base.Dispose(isDisposing);
+            request?.Cancel();
         }
     }
 }

osu.Game/Overlays/Profile/Sections/Recent/MedalIcon.cs

@@ -30,7 +30,7 @@ namespace osu.Game.Overlays.Profile.Sections.Recent
         }
 
         [BackgroundDependencyLoader]
-        private void load(TextureStore textures)
+        private void load(LargeTextureStore textures)
         {
             sprite.Texture = textures.Get(url);
         }

osu.Game/Overlays/Profile/Sections/Recent/PaginatedRecentActivityContainer.cs

@@ -12,6 +12,8 @@ namespace osu.Game.Overlays.Profile.Sections.Recent
 {
     public class PaginatedRecentActivityContainer : PaginatedContainer
     {
+        private GetUserRecentActivitiesRequest request;
+
         public PaginatedRecentActivityContainer(Bindable<User> user, string header, string missing)
             : base(user, header, missing)
         {
@@ -22,9 +24,8 @@ namespace osu.Game.Overlays.Profile.Sections.Recent
         {
             base.ShowMore();
 
-            var req = new GetUserRecentActivitiesRequest(User.Value.Id, VisiblePages++ * ItemsPerPage);
-
-            req.Success += activities =>
+            request = new GetUserRecentActivitiesRequest(User.Value.Id, VisiblePages++ * ItemsPerPage);
+            request.Success += activities => Schedule(() =>
             {
                 ShowMoreButton.FadeTo(activities.Count == ItemsPerPage ? 1 : 0);
                 ShowMoreLoading.Hide();
@@ -41,9 +42,15 @@ namespace osu.Game.Overlays.Profile.Sections.Recent
                 {
                     ItemsContainer.Add(new DrawableRecentActivity(activity));
                 }
-            };
+            });
 
-            Api.Queue(req);
+            Api.Queue(request);
+        }
+
+        protected override void Dispose(bool isDisposing)
+        {
+            base.Dispose(isDisposing);
+            request?.Cancel();
         }
     }
 }

osu.Game/Overlays/Settings/Sections/Debug/GCSettings.cs

@@ -13,15 +13,18 @@ namespace osu.Game.Overlays.Settings.Sections.Debug
     {
         protected override string Header => "Garbage Collector";
 
+        private readonly Bindable<LatencyMode> latencyMode = new Bindable<LatencyMode>();
+        private Bindable<GCLatencyMode> configLatencyMode;
+
         [BackgroundDependencyLoader]
         private void load(FrameworkDebugConfigManager config)
         {
             Children = new Drawable[]
             {
-                new SettingsEnumDropdown<GCLatencyMode>
+                new SettingsEnumDropdown<LatencyMode>
                 {
                     LabelText = "Active mode",
-                    Bindable = config.GetBindable<GCLatencyMode>(DebugSetting.ActiveGCMode)
+                    Bindable = latencyMode
                 },
                 new SettingsButton
                 {
@@ -29,6 +32,18 @@ namespace osu.Game.Overlays.Settings.Sections.Debug
                     Action = GC.Collect
                 },
             };
+
+            configLatencyMode = config.GetBindable<GCLatencyMode>(DebugSetting.ActiveGCMode);
+            configLatencyMode.BindValueChanged(v => latencyMode.Value = (LatencyMode)v, true);
+            latencyMode.BindValueChanged(v => configLatencyMode.Value = (GCLatencyMode)v);
+        }
+
+        private enum LatencyMode
+        {
+            Batch = GCLatencyMode.Batch,
+            Interactive = GCLatencyMode.Interactive,
+            LowLatency = GCLatencyMode.LowLatency,
+            SustainedLowLatency = GCLatencyMode.SustainedLowLatency
         }
     }
 }

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

@@ -1,8 +1,12 @@
 // Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
+using System.Collections.Generic;
+using System.Drawing;
+using System.Linq;
 using osu.Framework.Allocation;
 using osu.Framework.Configuration;
+using osu.Framework.Extensions.IEnumerableExtensions;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 
@@ -15,21 +19,36 @@ namespace osu.Game.Overlays.Settings.Sections.Graphics
         private FillFlowContainer letterboxSettings;
 
         private Bindable<bool> letterboxing;
+        private Bindable<Size> sizeFullscreen;
+
+        private OsuGameBase game;
+        private SettingsDropdown<Size> resolutionDropdown;
+        private SettingsEnumDropdown<WindowMode> windowModeDropdown;
 
         private const int transition_duration = 400;
 
         [BackgroundDependencyLoader]
-        private void load(FrameworkConfigManager config)
+        private void load(FrameworkConfigManager config, OsuGameBase game)
         {
+            this.game = game;
+
             letterboxing = config.GetBindable<bool>(FrameworkSetting.Letterboxing);
+            sizeFullscreen = config.GetBindable<Size>(FrameworkSetting.SizeFullscreen);
 
             Children = new Drawable[]
             {
-                new SettingsEnumDropdown<WindowMode>
+                windowModeDropdown = new SettingsEnumDropdown<WindowMode>
                 {
                     LabelText = "Screen mode",
                     Bindable = config.GetBindable<WindowMode>(FrameworkSetting.WindowMode),
                 },
+                resolutionDropdown = new SettingsDropdown<Size>
+                {
+                    LabelText = "Resolution",
+                    ShowsDefaultIndicator = false,
+                    Items = getResolutions(),
+                    Bindable = sizeFullscreen
+                },
                 new SettingsCheckbox
                 {
                     LabelText = "Letterboxing",
@@ -62,15 +81,39 @@ namespace osu.Game.Overlays.Settings.Sections.Graphics
                 },
             };
 
-            letterboxing.ValueChanged += isVisible =>
+            windowModeDropdown.Bindable.BindValueChanged(windowMode =>
+            {
+                if (windowMode == WindowMode.Fullscreen)
+                {
+                    resolutionDropdown.Show();
+                    sizeFullscreen.TriggerChange();
+                }
+                else
+                    resolutionDropdown.Hide();
+            }, true);
+
+            letterboxing.BindValueChanged(isVisible =>
             {
                 letterboxSettings.ClearTransforms();
                 letterboxSettings.AutoSizeAxes = isVisible ? Axes.Y : Axes.None;
 
                 if (!isVisible)
                     letterboxSettings.ResizeHeightTo(0, transition_duration, Easing.OutQuint);
-            };
-            letterboxing.TriggerChange();
+            }, true);
+        }
+
+        private IEnumerable<KeyValuePair<string, Size>> getResolutions()
+        {
+            var resolutions = new KeyValuePair<string, Size>("Default", new Size(9999, 9999)).Yield();
+
+            if (game.Window != null)
+                resolutions = resolutions.Concat(game.Window.AvailableResolutions
+                                                     .Where(r => r.Width >= 800 && r.Height >= 600)
+                                                     .OrderByDescending(r => r.Width)
+                                                     .ThenByDescending(r => r.Height)
+                                                     .Select(res => new KeyValuePair<string, Size>($"{res.Width}x{res.Height}", new Size(res.Width, res.Height)))
+                                                     .Distinct()).ToList();
+            return resolutions;
         }
     }
 }

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

@@ -7,6 +7,7 @@ using osu.Framework.Allocation;
 using osu.Framework.Graphics;
 using osu.Game.Beatmaps;
 using osu.Game.Graphics.UserInterface;
+using osu.Game.Skinning;
 
 namespace osu.Game.Overlays.Settings.Sections.Maintenance
 {
@@ -20,7 +21,7 @@ namespace osu.Game.Overlays.Settings.Sections.Maintenance
         protected override string Header => "General";
 
         [BackgroundDependencyLoader]
-        private void load(BeatmapManager beatmaps, DialogOverlay dialogOverlay)
+        private void load(BeatmapManager beatmaps, SkinManager skins, DialogOverlay dialogOverlay)
         {
             Children = new Drawable[]
             {
@@ -30,7 +31,7 @@ namespace osu.Game.Overlays.Settings.Sections.Maintenance
                     Action = () =>
                     {
                         importButton.Enabled.Value = false;
-                        beatmaps.ImportFromStable().ContinueWith(t => Schedule(() => importButton.Enabled.Value = true));
+                        beatmaps.ImportFromStableAsync().ContinueWith(t => Schedule(() => importButton.Enabled.Value = true));
                     }
                 },
                 deleteButton = new DangerousSettingsButton
@@ -45,6 +46,27 @@ namespace osu.Game.Overlays.Settings.Sections.Maintenance
                         }));
                     }
                 },
+                importButton = new SettingsButton
+                {
+                    Text = "Import skins from stable",
+                    Action = () =>
+                    {
+                        importButton.Enabled.Value = false;
+                        skins.ImportFromStableAsync().ContinueWith(t => Schedule(() => importButton.Enabled.Value = true));
+                    }
+                },
+                deleteButton = new DangerousSettingsButton
+                {
+                    Text = "Delete ALL skins",
+                    Action = () =>
+                    {
+                        dialogOverlay?.Push(new DeleteAllBeatmapsDialog(() =>
+                        {
+                            deleteButton.Enabled.Value = false;
+                            Task.Run(() => skins.Delete(skins.GetAllUserSkins())).ContinueWith(t => Schedule(() => deleteButton.Enabled.Value = true));
+                        }));
+                    }
+                },
                 restoreButton = new SettingsButton
                 {
                     Text = "Restore all hidden difficulties",

osu.Game/Overlays/Settings/Sections/SkinSection.cs

@@ -51,10 +51,10 @@ namespace osu.Game.Overlays.Settings.Sections
                 },
             };
 
-            skins.ItemAdded += onItemsChanged;
-            skins.ItemRemoved += onItemsChanged;
+            skins.ItemAdded += itemAdded;
+            skins.ItemRemoved += itemRemoved;
 
-            reloadSkins();
+            skinDropdown.Items = skins.GetAllUsableSkins().Select(s => new KeyValuePair<string, int>(s.ToString(), s.ID));
 
             var skinBindable = config.GetBindable<int>(OsuSetting.Skin);
 
@@ -65,9 +65,8 @@ namespace osu.Game.Overlays.Settings.Sections
             skinDropdown.Bindable = skinBindable;
         }
 
-        private void reloadSkins() => skinDropdown.Items = skins.GetAllUsableSkins().Select(s => new KeyValuePair<string, int>(s.ToString(), s.ID));
-
-        private void onItemsChanged(SkinInfo _) => Schedule(reloadSkins);
+        private void itemRemoved(SkinInfo s) => skinDropdown.Items = skinDropdown.Items.Where(i => i.Value != s.ID);
+        private void itemAdded(SkinInfo s) => skinDropdown.Items = skinDropdown.Items.Append(new KeyValuePair<string, int>(s.ToString(), s.ID));
 
         protected override void Dispose(bool isDisposing)
         {
@@ -75,8 +74,8 @@ namespace osu.Game.Overlays.Settings.Sections
 
             if (skins != null)
             {
-                skins.ItemAdded -= onItemsChanged;
-                skins.ItemRemoved -= onItemsChanged;
+                skins.ItemAdded -= itemAdded;
+                skins.ItemRemoved -= itemRemoved;
             }
         }
 

osu.Game/Overlays/Settings/SettingsSection.cs

@@ -73,7 +73,7 @@ namespace osu.Game.Overlays.Settings
                     },
                     RelativeSizeAxes = Axes.X,
                     AutoSizeAxes = Axes.Y,
-                    Children = new[]
+                    Children = new Drawable[]
                     {
                         new OsuSpriteText
                         {

osu.Game/Overlays/Settings/SidebarButton.cs

@@ -9,6 +9,7 @@ using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Shapes;
 using osu.Framework.Graphics.Sprites;
+using osu.Framework.Graphics.UserInterface;
 using osu.Framework.Input.States;
 using osu.Game.Graphics;
 using osu.Game.Graphics.Sprites;
@@ -16,7 +17,7 @@ using osu.Game.Graphics.UserInterface;
 
 namespace osu.Game.Overlays.Settings
 {
-    public class SidebarButton : OsuButton
+    public class SidebarButton : Button
     {
         private readonly SpriteIcon drawableIcon;
         private readonly SpriteText headerText;
@@ -97,7 +98,8 @@ namespace osu.Game.Overlays.Settings
                     Width = 5,
                     Anchor = Anchor.CentreRight,
                     Origin = Anchor.CentreRight,
-                }
+                },
+                new HoverClickSounds(HoverSampleSet.Loud),
             });
         }
 

osu.Game/Overlays/Toolbar/Toolbar.cs

@@ -83,14 +83,14 @@ namespace osu.Game.Overlays.Toolbar
         [BackgroundDependencyLoader(true)]
         private void load(OsuGame osuGame)
         {
-            if (osuGame != null)
-                overlayActivationMode.BindTo(osuGame.OverlayActivationMode);
-
             StateChanged += visibility =>
             {
                 if (overlayActivationMode == OverlayActivation.Disabled)
                     State = Visibility.Hidden;
             };
+
+            if (osuGame != null)
+                overlayActivationMode.BindTo(osuGame.OverlayActivationMode);
         }
 
         public class ToolbarBackground : Container

osu.Game/Overlays/UserProfileOverlay.cs

@@ -73,16 +73,15 @@ namespace osu.Game.Overlays
             FadeEdgeEffectTo(0, WaveContainer.DISAPPEAR_DURATION, Easing.Out);
         }
 
-        public void ShowUser(long userId)
-        {
-            if (userId == Header.User.Id)
-                return;
-
-            ShowUser(new User { Id = userId });
-        }
+        public void ShowUser(long userId) => ShowUser(new User { Id = userId });
 
         public void ShowUser(User user, bool fetchOnline = true)
         {
+            Show();
+
+            if (user.Id == Header?.User.Id)
+                return;
+
             userReq?.Cancel();
             Clear();
             lastSection = null;
@@ -97,6 +96,7 @@ namespace osu.Game.Overlays
                 new BeatmapsSection(),
                 new KudosuSection()
             };
+
             tabs = new ProfileTabControl
             {
                 RelativeSizeAxes = Axes.X,
@@ -161,7 +161,6 @@ namespace osu.Game.Overlays
                 userLoadComplete(user);
             }
 
-            Show();
             sectionsContainer.ScrollToTop();
         }
 

osu.Game/Rulesets/Mods/IUpdatableByPlayfield.cs

@@ -0,0 +1,12 @@
+// Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
+// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
+
+using osu.Game.Rulesets.UI;
+
+namespace osu.Game.Rulesets.Mods
+{
+    public interface IUpdatableByPlayfield : IApplicableMod
+    {
+        void Update(Playfield playfield);
+    }
+}

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

@@ -10,6 +10,8 @@ using System.IO;
 using osu.Game.Beatmaps.Formats;
 using osu.Game.Audio;
 using System.Linq;
+using JetBrains.Annotations;
+using osu.Framework.Logging;
 using osu.Framework.MathUtils;
 
 namespace osu.Game.Rulesets.Objects.Legacy
@@ -37,6 +39,7 @@ namespace osu.Game.Rulesets.Objects.Legacy
             FormatVersion = formatVersion;
         }
 
+        [CanBeNull]
         public override HitObject Parse(string text)
         {
             try
@@ -191,7 +194,10 @@ namespace osu.Game.Rulesets.Objects.Legacy
                 }
 
                 if (result == null)
-                    throw new InvalidOperationException($@"Unknown hit object type {type}.");
+                {
+                    Logger.Log($"Unknown hit object type: {type}. Skipped.", level: LogLevel.Error);
+                    return null;
+                }
 
                 result.StartTime = Convert.ToDouble(split[2], CultureInfo.InvariantCulture) + Offset;
                 result.Samples = convertSoundType(soundType, bankInfo);

osu.Game/Rulesets/UI/Playfield.cs

@@ -9,6 +9,8 @@ using osu.Game.Rulesets.Objects.Drawables;
 using osu.Framework.Allocation;
 using osu.Framework.Extensions.IEnumerableExtensions;
 using osu.Framework.Configuration;
+using osu.Game.Beatmaps;
+using osu.Game.Rulesets.Mods;
 
 namespace osu.Game.Rulesets.UI
 {
@@ -17,12 +19,12 @@ namespace osu.Game.Rulesets.UI
         /// <summary>
         /// The <see cref="DrawableHitObject"/> contained in this Playfield.
         /// </summary>
-        public HitObjectContainer HitObjects { get; private set; }
+        public HitObjectContainer HitObjectContainer { get; private set; }
 
         /// <summary>
         /// All the <see cref="DrawableHitObject"/>s contained in this <see cref="Playfield"/> and all <see cref="NestedPlayfields"/>.
         /// </summary>
-        public IEnumerable<DrawableHitObject> AllHitObjects => HitObjects?.Objects.Concat(NestedPlayfields.SelectMany(p => p.AllHitObjects)) ?? Enumerable.Empty<DrawableHitObject>();
+        public IEnumerable<DrawableHitObject> AllHitObjects => HitObjectContainer?.Objects.Concat(NestedPlayfields.SelectMany(p => p.AllHitObjects)) ?? Enumerable.Empty<DrawableHitObject>();
 
         /// <summary>
         /// All <see cref="Playfield"/>s nested inside this <see cref="Playfield"/>.
@@ -51,13 +53,17 @@ namespace osu.Game.Rulesets.UI
             RelativeSizeAxes = Axes.Both;
         }
 
-        [BackgroundDependencyLoader]
-        private void load()
-        {
-            HitObjects = CreateHitObjectContainer();
-            HitObjects.RelativeSizeAxes = Axes.Both;
+        private WorkingBeatmap beatmap;
 
-            Add(HitObjects);
+        [BackgroundDependencyLoader]
+        private void load(IBindableBeatmap beatmap)
+        {
+            this.beatmap = beatmap.Value;
+
+            HitObjectContainer = CreateHitObjectContainer();
+            HitObjectContainer.RelativeSizeAxes = Axes.Both;
+
+            Add(HitObjectContainer);
         }
 
         /// <summary>
@@ -69,13 +75,13 @@ namespace osu.Game.Rulesets.UI
         /// Adds a DrawableHitObject to this Playfield.
         /// </summary>
         /// <param name="h">The DrawableHitObject to add.</param>
-        public virtual void Add(DrawableHitObject h) => HitObjects.Add(h);
+        public virtual void Add(DrawableHitObject h) => HitObjectContainer.Add(h);
 
         /// <summary>
         /// Remove a DrawableHitObject from this Playfield.
         /// </summary>
         /// <param name="h">The DrawableHitObject to remove.</param>
-        public virtual void Remove(DrawableHitObject h) => HitObjects.Remove(h);
+        public virtual void Remove(DrawableHitObject h) => HitObjectContainer.Remove(h);
 
         /// <summary>
         /// Registers a <see cref="Playfield"/> as a nested <see cref="Playfield"/>.
@@ -92,5 +98,15 @@ namespace osu.Game.Rulesets.UI
         /// Creates the container that will be used to contain the <see cref="DrawableHitObject"/>s.
         /// </summary>
         protected virtual HitObjectContainer CreateHitObjectContainer() => new HitObjectContainer();
+
+        protected override void Update()
+        {
+            base.Update();
+
+            if (beatmap != null)
+                foreach (var mod in beatmap.Mods.Value)
+                    if (mod is IUpdatableByPlayfield updatable)
+                        updatable.Update(this);
+        }
     }
 }

osu.Game/Rulesets/UI/RulesetContainer.cs

@@ -306,7 +306,7 @@ namespace osu.Game.Rulesets.UI
             Playfield.PostProcess();
 
             foreach (var mod in Mods.OfType<IApplicableToDrawableHitObjects>())
-                mod.ApplyToDrawableHitObjects(Playfield.HitObjects.Objects);
+                mod.ApplyToDrawableHitObjects(Playfield.HitObjectContainer.Objects);
         }
 
         protected override void Update()

osu.Game/Rulesets/UI/Scrolling/ScrollingPlayfield.cs

@@ -55,7 +55,7 @@ namespace osu.Game.Rulesets.UI.Scrolling
         /// <summary>
         /// The container that contains the <see cref="DrawableHitObject"/>s.
         /// </summary>
-        public new ScrollingHitObjectContainer HitObjects => (ScrollingHitObjectContainer)base.HitObjects;
+        public new ScrollingHitObjectContainer HitObjects => (ScrollingHitObjectContainer)HitObjectContainer;
 
         /// <summary>
         /// The direction in which <see cref="DrawableHitObject"/>s in this <see cref="ScrollingPlayfield"/> should scroll.

osu.Game/Screens/Edit/Components/CircularButton.cs

@@ -0,0 +1,25 @@
+// Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
+// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
+
+using osu.Game.Graphics.UserInterface;
+using OpenTK;
+
+namespace osu.Game.Screens.Edit.Components
+{
+    public class CircularButton : OsuButton
+    {
+        private const float width = 125;
+        private const float height = 30;
+
+        public CircularButton()
+        {
+            Size = new Vector2(width, height);
+        }
+
+        protected override void Update()
+        {
+            base.Update();
+            Content.CornerRadius = DrawHeight / 2f;
+        }
+    }
+}

osu.Game/Screens/Loader.cs

@@ -9,6 +9,7 @@ using osu.Framework.Graphics.Shaders;
 using osu.Game.Screens.Menu;
 using OpenTK;
 using osu.Framework.Screens;
+using osu.Game.Overlays;
 
 namespace osu.Game.Screens
 {
@@ -18,6 +19,8 @@ namespace osu.Game.Screens
 
         protected override bool HideOverlaysOnEnter => true;
 
+        protected override OverlayActivation InitialOverlayActivationMode => OverlayActivation.Disabled;
+
         protected override bool AllowBackButton => false;
 
         public Loader()

osu.Game/Screens/Menu/ButtonSystem.cs

@@ -174,6 +174,9 @@ namespace osu.Game.Screens.Menu
                 ButtonSystemState lastState = state;
                 state = value;
 
+                if (game != null)
+                    game.OverlayActivationMode.Value = state == ButtonSystemState.Exit ? OverlayActivation.Disabled : OverlayActivation.All;
+
                 updateLogoState(lastState);
 
                 Logger.Log($"{nameof(ButtonSystem)}'s state changed from {lastState} to {state}");
@@ -205,11 +208,7 @@ namespace osu.Game.Screens.Menu
                         {
                             logoTracking = false;
 
-                            if (game != null)
-                            {
-                                game.OverlayActivationMode.Value = state == ButtonSystemState.Exit ? OverlayActivation.Disabled : OverlayActivation.All;
-                                game.Toolbar.Hide();
-                            }
+                            game?.Toolbar.Hide();
 
                             logo.ClearTransforms(targetMember: nameof(Position));
                             logo.RelativePositionAxes = Axes.Both;
@@ -243,11 +242,7 @@ namespace osu.Game.Screens.Menu
                                 if (impact)
                                     logo.Impact();
 
-                                if (game != null)
-                                {
-                                    game.OverlayActivationMode.Value = OverlayActivation.All;
-                                    game.Toolbar.State = Visibility.Visible;
-                                }
+                                game?.Toolbar.Show();
                             }, 200);
                             break;
                         default:
@@ -278,7 +273,7 @@ namespace osu.Game.Screens.Menu
 
             if (logo != null)
             {
-                if (logoTracking && iconFacade.IsLoaded)
+                if (logoTracking && logo.RelativePositionAxes == Axes.None && iconFacade.IsLoaded)
                     logo.Position = logoTrackingPosition;
 
                 iconFacade.Width = logo.SizeForFlow * 0.5f;

osu.Game/Screens/Menu/LogoVisualisation.cs

@@ -176,7 +176,7 @@ namespace osu.Game.Screens.Menu
 
                 Vector2 inflation = DrawInfo.MatrixInverse.ExtractScale().Xy;
 
-                ColourInfo colourInfo = DrawInfo.Colour;
+                ColourInfo colourInfo = DrawColourInfo.Colour;
                 colourInfo.ApplyChild(Colour);
 
                 if (AudioData != null)

osu.Game/Screens/Play/Break/BreakArrows.cs

@@ -31,23 +31,30 @@ namespace osu.Game.Screens.Play.Break
             RelativeSizeAxes = Axes.Both;
             InternalChildren = new Drawable[]
             {
-                leftGlowIcon = new GlowIcon
+                new ParallaxContainer
                 {
-                    Anchor = Anchor.Centre,
-                    Origin = Anchor.CentreRight,
-                    X = -glow_icon_offscreen_offset,
-                    Icon = Graphics.FontAwesome.fa_chevron_right,
-                    BlurSigma = new Vector2(glow_icon_blur_sigma),
-                    Size = new Vector2(glow_icon_size),
-                },
-                rightGlowIcon = new GlowIcon
-                {
-                    Anchor = Anchor.Centre,
-                    Origin = Anchor.CentreLeft,
-                    X = glow_icon_offscreen_offset,
-                    Icon = Graphics.FontAwesome.fa_chevron_left,
-                    BlurSigma = new Vector2(glow_icon_blur_sigma),
-                    Size = new Vector2(glow_icon_size),
+                    ParallaxAmount = -0.01f,
+                    Children = new Drawable[]
+                    {
+                        leftGlowIcon = new GlowIcon
+                        {
+                            Anchor = Anchor.Centre,
+                            Origin = Anchor.CentreRight,
+                            X = -glow_icon_offscreen_offset,
+                            Icon = Graphics.FontAwesome.fa_chevron_right,
+                            BlurSigma = new Vector2(glow_icon_blur_sigma),
+                            Size = new Vector2(glow_icon_size),
+                        },
+                        rightGlowIcon = new GlowIcon
+                        {
+                            Anchor = Anchor.Centre,
+                            Origin = Anchor.CentreLeft,
+                            X = glow_icon_offscreen_offset,
+                            Icon = Graphics.FontAwesome.fa_chevron_left,
+                            BlurSigma = new Vector2(glow_icon_blur_sigma),
+                            Size = new Vector2(glow_icon_size),
+                        },
+                    }
                 },
                 new ParallaxContainer
                 {

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

@@ -63,6 +63,12 @@ namespace osu.Game.Screens.Play.HUD
             };
         }
 
+        protected override void Dispose(bool isDisposing)
+        {
+            base.Dispose(isDisposing);
+            mods.UnbindAll();
+        }
+
         protected override void LoadComplete()
         {
             base.LoadComplete();

osu.Game/Screens/Play/Player.cs

@@ -124,7 +124,7 @@ namespace osu.Game.Screens.Play
 
                 if (!RulesetContainer.Objects.Any())
                 {
-                    Logger.Error(new InvalidOperationException("Beatmap contains no hit objects!"), "Beatmap contains no hit objects!");
+                    Logger.Log("Beatmap contains no hit objects!", level: LogLevel.Error);
                     return;
                 }
             }

osu.Game/Screens/Ranking/ResultsPageScore.cs

@@ -29,6 +29,7 @@ namespace osu.Game.Screens.Ranking
 {
     public class ResultsPageScore : ResultsPage
     {
+        private Container scoreContainer;
         private ScoreCounter scoreCounter;
 
         public ResultsPageScore(Score score, WorkingBeatmap beatmap) : base(score, beatmap) { }
@@ -76,7 +77,7 @@ namespace osu.Game.Screens.Ranking
                             Size = new Vector2(150, 60),
                             Margin = new MarginPadding(20),
                         },
-                        new Container
+                        scoreContainer = new Container
                         {
                             Anchor = Anchor.TopCentre,
                             Origin = Anchor.TopCentre,
@@ -92,8 +93,8 @@ namespace osu.Game.Screens.Ranking
                                 },
                                 scoreCounter = new SlowScoreCounter(6)
                                 {
-                                    Anchor = Anchor.TopCentre,
-                                    Origin = Anchor.TopCentre,
+                                    Anchor = Anchor.Centre,
+                                    Origin = Anchor.Centre,
                                     Colour = colours.PinkDarker,
                                     Y = 10,
                                     TextSize = 56,
@@ -185,6 +186,13 @@ namespace osu.Game.Screens.Ranking
             });
         }
 
+        protected override void UpdateAfterChildren()
+        {
+            base.UpdateAfterChildren();
+
+            scoreCounter.Scale = new Vector2(Math.Min(1f, (scoreContainer.DrawWidth - 20) / scoreCounter.DrawWidth));
+        }
+
         private class DrawableScoreStatistic : Container
         {
             private readonly KeyValuePair<HitResult, object> statistic;
@@ -368,7 +376,7 @@ namespace osu.Game.Screens.Ranking
             }
 
             [BackgroundDependencyLoader]
-            private void load(TextureStore textures)
+            private void load(LargeTextureStore textures)
             {
                 if (!string.IsNullOrEmpty(user.CoverUrl))
                     cover.Texture = textures.Get(user.CoverUrl);

osu.Game/Screens/Select/BeatmapCarousel.cs

@@ -64,32 +64,36 @@ namespace osu.Game.Screens.Select
 
         public IEnumerable<BeatmapSetInfo> BeatmapSets
         {
-            get { return beatmapSets.Select(g => g.BeatmapSet); }
-            set
+            get => beatmapSets.Select(g => g.BeatmapSet);
+            set => loadBeatmapSets(() => value);
+        }
+
+        public void LoadBeatmapSetsFromManager(BeatmapManager manager) => loadBeatmapSets(manager.GetAllUsableBeatmapSetsEnumerable);
+
+        private void loadBeatmapSets(Func<IEnumerable<BeatmapSetInfo>> beatmapSets)
+        {
+            CarouselRoot newRoot = new CarouselRoot(this);
+
+            Task.Run(() =>
             {
-                CarouselRoot newRoot = new CarouselRoot(this);
+                beatmapSets().Select(createCarouselSet).Where(g => g != null).ForEach(newRoot.AddChild);
+                newRoot.Filter(activeCriteria);
 
-                Task.Run(() =>
+                // preload drawables as the ctor overhead is quite high currently.
+                var _ = newRoot.Drawables;
+            }).ContinueWith(_ => Schedule(() =>
+            {
+                root = newRoot;
+                scrollableContent.Clear(false);
+                itemsCache.Invalidate();
+                scrollPositionCache.Invalidate();
+
+                Schedule(() =>
                 {
-                    value.Select(createCarouselSet).Where(g => g != null).ForEach(newRoot.AddChild);
-                    newRoot.Filter(activeCriteria);
-
-                    // preload drawables as the ctor overhead is quite high currently.
-                    var _ = newRoot.Drawables;
-                }).ContinueWith(_ => Schedule(() =>
-                {
-                    root = newRoot;
-                    scrollableContent.Clear(false);
-                    itemsCache.Invalidate();
-                    scrollPositionCache.Invalidate();
-
-                    Schedule(() =>
-                    {
-                        BeatmapSetsChanged?.Invoke();
-                        initialLoadComplete = true;
-                    });
-                }));
-            }
+                    BeatmapSetsChanged?.Invoke();
+                    initialLoadComplete = true;
+                });
+            }));
         }
 
         private readonly List<float> yPositions = new List<float>();
@@ -482,6 +486,15 @@ namespace osu.Game.Screens.Select
                 updateItem(p, halfHeight);
         }
 
+        protected override void Dispose(bool isDisposing)
+        {
+            base.Dispose(isDisposing);
+
+            // aggressively dispose "off-screen" items to reduce GC pressure.
+            foreach (var i in Items)
+                i.Dispose();
+        }
+
         private CarouselBeatmapSet createCarouselSet(BeatmapSetInfo beatmapSet)
         {
             if (beatmapSet.Beatmaps.All(b => b.Hidden))

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

@@ -50,12 +50,12 @@ namespace osu.Game.Screens.Select.Carousel
 
             Children = new Drawable[]
             {
-                new DelayedLoadWrapper(
+                new DelayedLoadUnloadWrapper(() =>
                     new PanelBackground(manager.GetWorkingBeatmap(beatmapSet.Beatmaps.FirstOrDefault()))
                     {
                         RelativeSizeAxes = Axes.Both,
                         OnLoadComplete = d => d.FadeInFromZero(1000, Easing.OutQuint),
-                    }, 300
+                    }, 300, 5000
                 ),
                 new FillFlowContainer
                 {

osu.Game/Screens/Select/ImportFromStablePopup.cs

@@ -12,7 +12,7 @@ namespace osu.Game.Screens.Select
         public ImportFromStablePopup(Action importFromStable)
         {
             HeaderText = @"You have no beatmaps!";
-            BodyText = "An existing copy of osu! was found, though.\nWould you like to import your beatmaps?";
+            BodyText = "An existing copy of osu! was found, though.\nWould you like to import your beatmaps (and skins)?";
 
             Icon = FontAwesome.fa_plane;
 

osu.Game/Screens/Select/Leaderboards/DrawableRank.cs

@@ -41,7 +41,10 @@ namespace osu.Game.Screens.Select.Leaderboards
             updateTexture();
         }
 
-        private void updateTexture() => rankSprite.Texture = textures.Get($@"Grades/{Rank.GetDescription()}");
+        private void updateTexture()
+        {
+            rankSprite.Texture = textures.Get($@"Grades/{Rank.GetDescription()}");
+        }
 
         public void UpdateRank(ScoreRank newRank)
         {

osu.Game/Screens/Select/PlaySongSelect.cs

@@ -3,7 +3,6 @@
 
 using System.Collections.Generic;
 using System.Linq;
-using System.Threading.Tasks;
 using OpenTK.Input;
 using osu.Framework.Allocation;
 using osu.Framework.Audio;
@@ -20,6 +19,7 @@ using osu.Game.Rulesets.Mods;
 using osu.Game.Screens.Edit;
 using osu.Game.Screens.Play;
 using osu.Game.Screens.Ranking;
+using osu.Game.Skinning;
 
 namespace osu.Game.Screens.Select
 {
@@ -55,7 +55,7 @@ namespace osu.Game.Screens.Select
         private readonly Bindable<IEnumerable<Mod>> selectedMods = new Bindable<IEnumerable<Mod>>(new Mod[] { });
 
         [BackgroundDependencyLoader(true)]
-        private void load(OsuColour colours, AudioManager audio, BeatmapManager beatmaps, DialogOverlay dialogOverlay, Bindable<IEnumerable<Mod>> selectedMods)
+        private void load(OsuColour colours, AudioManager audio, BeatmapManager beatmaps, SkinManager skins, DialogOverlay dialogOverlay, Bindable<IEnumerable<Mod>> selectedMods)
         {
             if (selectedMods != null) this.selectedMods.BindTo(selectedMods);
 
@@ -78,7 +78,10 @@ namespace osu.Game.Screens.Select
                     // if we have no beatmaps but osu-stable is found, let's prompt the user to import.
                     if (!beatmaps.GetAllUsableBeatmapSets().Any() && beatmaps.StableInstallationAvailable)
                         dialogOverlay.Push(new ImportFromStablePopup(() =>
-                            Task.Factory.StartNew(beatmaps.ImportFromStable, TaskCreationOptions.LongRunning)));
+                        {
+                            beatmaps.ImportFromStableAsync();
+                            skins.ImportFromStableAsync();
+                        }));
                 });
             }
         }

osu.Game/Screens/Select/SongSelect.cs

@@ -221,7 +221,7 @@ namespace osu.Game.Screens.Select
             sampleChangeDifficulty = audio.Sample.Get(@"SongSelect/select-difficulty");
             sampleChangeBeatmap = audio.Sample.Get(@"SongSelect/select-expand");
 
-            Carousel.BeatmapSets = this.beatmaps.GetAllUsableBeatmapSetsEnumerable();
+            Carousel.LoadBeatmapSetsFromManager(this.beatmaps);
         }
 
         public void Edit(BeatmapInfo beatmap)

osu.Game/Screens/Tournament/Drawings.cs

@@ -59,7 +59,7 @@ namespace osu.Game.Screens.Tournament
 
             TextureStore flagStore = new TextureStore();
             // Local flag store
-            flagStore.AddStore(new RawTextureLoaderStore(new NamespacedResourceStore<byte[]>(new StorageBackedResourceStore(storage), "Drawings")));
+            flagStore.AddStore(new TextureLoaderStore(new NamespacedResourceStore<byte[]>(new StorageBackedResourceStore(storage), "Drawings")));
             // Default texture store
             flagStore.AddStore(textures);
 

osu.Game/Skinning/LegacySkin.cs

@@ -4,6 +4,7 @@
 using System;
 using System.IO;
 using System.Linq;
+using System.Threading.Tasks;
 using osu.Framework.Audio;
 using osu.Framework.Audio.Sample;
 using osu.Framework.Graphics;
@@ -36,7 +37,7 @@ namespace osu.Game.Skinning
                 Configuration = new SkinConfiguration();
 
             Samples = audioManager.GetSampleManager(storage);
-            Textures = new TextureStore(new RawTextureLoaderStore(storage));
+            Textures = new TextureStore(new TextureLoaderStore(storage));
         }
 
         public override Drawable GetDrawableComponent(string componentName)
@@ -108,10 +109,12 @@ namespace osu.Game.Skinning
                 return path == null ? null : underlyingStore.GetStream(path);
             }
 
-            byte[] IResourceStore<byte[]>.Get(string name)
+            byte[] IResourceStore<byte[]>.Get(string name) => GetAsync(name).Result;
+
+            public Task<byte[]> GetAsync(string name)
             {
                 string path = getPathForFile(name);
-                return path == null ? null : underlyingStore.Get(path);
+                return path == null ? Task.FromResult<byte[]>(null) : underlyingStore.GetAsync(path);
             }
 
             #region IDisposable Support

osu.Game/Skinning/LocalSkinOverrideContainer.cs

@@ -85,12 +85,10 @@ namespace osu.Game.Skinning
         private void load(OsuConfigManager config)
         {
             beatmapSkins = config.GetBindable<bool>(OsuSetting.BeatmapSkins);
-            beatmapSkins.ValueChanged += val => onSourceChanged();
-            beatmapSkins.TriggerChange();
+            beatmapSkins.BindValueChanged(_ => onSourceChanged());
 
             beatmapHitsounds = config.GetBindable<bool>(OsuSetting.BeatmapHitsounds);
-            beatmapHitsounds.ValueChanged += val => onSourceChanged();
-            beatmapHitsounds.TriggerChange();
+            beatmapHitsounds.BindValueChanged(_ => onSourceChanged(), true);
         }
 
         protected override void LoadComplete()

osu.Game/Skinning/SkinManager.cs

@@ -26,17 +26,25 @@ namespace osu.Game.Skinning
 
         public override string[] HandledExtensions => new[] { ".osk" };
 
+        protected override string ImportFromStablePath => "Skins";
+
         /// <summary>
-        /// Returns a list of all usable <see cref="SkinInfo"/>s.
+        /// Returns a list of all usable <see cref="SkinInfo"/>s. Includes the special default skin plus all skins from <see cref="GetAllUserSkins"/>.
         /// </summary>
         /// <returns>A list of available <see cref="SkinInfo"/>.</returns>
         public List<SkinInfo> GetAllUsableSkins()
         {
-            var userSkins = ModelStore.ConsumableItems.Where(s => !s.DeletePending).ToList();
+            var userSkins = GetAllUserSkins();
             userSkins.Insert(0, SkinInfo.Default);
             return userSkins;
         }
 
+        /// <summary>
+        /// Returns a list of all usable <see cref="SkinInfo"/>s that have been loaded by the user.
+        /// </summary>
+        /// <returns>A list of available <see cref="SkinInfo"/>.</returns>
+        public List<SkinInfo> GetAllUserSkins() => ModelStore.ConsumableItems.Where(s => !s.DeletePending).ToList();
+
         protected override SkinInfo CreateModel(ArchiveReader archive) => new SkinInfo
         {
             Name = archive.Name
@@ -85,6 +93,13 @@ namespace osu.Game.Skinning
         {
             this.audio = audio;
 
+            ItemRemoved += removedInfo =>
+            {
+                // check the removed skin is not the current user choice. if it is, switch back to default.
+                if (removedInfo.ID == CurrentSkinInfo.Value.ID)
+                    CurrentSkinInfo.Value = SkinInfo.Default;
+            };
+
             CurrentSkinInfo.ValueChanged += info => CurrentSkin.Value = GetSkin(info);
             CurrentSkin.ValueChanged += skin =>
             {
@@ -93,16 +108,6 @@ namespace osu.Game.Skinning
 
                 SourceChanged?.Invoke();
             };
-
-            // migrate older imports which didn't have access to skin.ini
-            using (ContextFactory.GetForWrite())
-            {
-                foreach (var skinInfo in ModelStore.ConsumableItems.Where(s => s.Name.EndsWith(".osk")))
-                {
-                    populate(skinInfo);
-                    Update(skinInfo);
-                }
-            }
         }
 
         /// <summary>

osu.Game/Skinning/SkinReloadableDrawable.cs

@@ -52,5 +52,13 @@ namespace osu.Game.Skinning
         protected virtual void SkinChanged(ISkinSource skin, bool allowFallback)
         {
         }
+
+        protected override void Dispose(bool isDisposing)
+        {
+            base.Dispose(isDisposing);
+
+            if (skin != null)
+                skin.SourceChanged -= onChange;
+        }
     }
 }

osu.Game/Storyboards/Drawables/DrawableStoryboard.cs

@@ -57,7 +57,7 @@ namespace osu.Game.Storyboards.Drawables
         [BackgroundDependencyLoader]
         private void load(FileStore fileStore)
         {
-            dependencies.Cache(new TextureStore(new RawTextureLoaderStore(fileStore.Store), false) { ScaleAdjust = 1, });
+            dependencies.Cache(new TextureStore(new TextureLoaderStore(fileStore.Store), false, scaleAdjust: 1));
 
             foreach (var layer in Storyboard.Layers)
                 Add(layer.CreateDrawable());

osu.Game/Users/Avatar.cs

@@ -24,7 +24,7 @@ namespace osu.Game.Users
         }
 
         [BackgroundDependencyLoader]
-        private void load(TextureStore textures)
+        private void load(LargeTextureStore textures)
         {
             if (textures == null)
                 throw new ArgumentNullException(nameof(textures));

osu.Game/Users/UserCoverBackground.cs

@@ -18,7 +18,7 @@ namespace osu.Game.Users
         }
 
         [BackgroundDependencyLoader]
-        private void load(TextureStore textures)
+        private void load(LargeTextureStore textures)
         {
             if (textures == null)
                 throw new ArgumentNullException(nameof(textures));