Merge remote-tracking branch 'refs/remotes/ppy/master' into mods_overlay_fix

.vscode/tasks.json

@@ -7,17 +7,11 @@
     "command": "msbuild",
     "suppressTaskName": true,
     "showOutput": "silent",
-    "args": [
-        "/property:GenerateFullPaths=true",
-        "/property:DebugType=portable"
-    ],
-    "windows": {
     "args": [
         "/property:GenerateFullPaths=true",
         "/property:DebugType=portable",
-            "/m" //parallel compiling support. doesn't work well with mono atm
+        "/m" //parallel compiling support.
-        ]
+    ],
-    },
     "tasks": [
         {
             "taskName": "Build (Debug)",

osu-framework

@@ -1 +1 @@
-Subproject commit af9ffbd8b945e526801c469dd55464363e502962
+Subproject commit 46a56e0e11d56c788ff8db089582718a606ed158

osu.Desktop.VisualTests/Tests/TestCaseBeatSyncedContainer.cs

@@ -0,0 +1,206 @@
+// Copyright (c) 2007-2017 ppy Pty Ltd <contact@ppy.sh>.
+// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
+
+using osu.Framework.Testing;
+using osu.Framework.Graphics;
+using osu.Framework.Timing;
+using osu.Game.Overlays;
+using osu.Framework.Graphics.Containers;
+using osu.Game.Graphics.Containers;
+using osu.Framework.Audio.Track;
+using osu.Game.Beatmaps.ControlPoints;
+using osu.Framework.Graphics.Shapes;
+using OpenTK.Graphics;
+using osu.Game.Graphics.Sprites;
+using osu.Framework.Lists;
+using System;
+using osu.Framework.Extensions.Color4Extensions;
+
+namespace osu.Desktop.VisualTests.Tests
+{
+    internal class TestCaseBeatSyncedContainer : TestCase
+    {
+        public override string Description => @"Tests beat synced containers.";
+
+        private readonly MusicController mc;
+
+        public TestCaseBeatSyncedContainer()
+        {
+            Clock = new FramedClock();
+            Clock.ProcessFrame();
+
+            Add(new BeatContainer
+            {
+                Anchor = Anchor.BottomCentre,
+                Origin = Anchor.BottomCentre,
+            });
+
+            Add(mc = new MusicController
+            {
+                Origin = Anchor.TopRight,
+                Anchor = Anchor.TopRight,
+            });
+        }
+
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+            mc.ToggleVisibility();
+        }
+
+        private class BeatContainer : BeatSyncedContainer
+        {
+            private const int flash_layer_heigth = 150;
+
+            private readonly InfoString timingPointCount;
+            private readonly InfoString currentTimingPoint;
+            private readonly InfoString beatCount;
+            private readonly InfoString currentBeat;
+            private readonly InfoString beatsPerMinute;
+            private readonly InfoString adjustedBeatLength;
+            private readonly InfoString timeUntilNextBeat;
+            private readonly InfoString timeSinceLastBeat;
+
+            private readonly Box flashLayer;
+
+            public BeatContainer()
+            {
+                RelativeSizeAxes = Axes.X;
+                AutoSizeAxes = Axes.Y;
+                Children = new Drawable[]
+                {
+                    new Container
+                    {
+                        Name = @"Info Layer",
+                        Anchor = Anchor.BottomLeft,
+                        Origin = Anchor.BottomLeft,
+                        AutoSizeAxes = Axes.Both,
+                        Margin = new MarginPadding { Bottom = flash_layer_heigth },
+                        Children = new Drawable[]
+                        {
+                            new Box
+                            {
+                                RelativeSizeAxes = Axes.Both,
+                                Colour = Color4.Black.Opacity(150),
+                            },
+                            new FillFlowContainer
+                            {
+                                Anchor = Anchor.BottomLeft,
+                                Origin = Anchor.BottomLeft,
+                                AutoSizeAxes = Axes.Both,
+                                Direction = FillDirection.Vertical,
+                                Children = new Drawable[]
+                                {
+                                    timingPointCount = new InfoString(@"Timing points amount"),
+                                    currentTimingPoint = new InfoString(@"Current timing point"),
+                                    beatCount = new InfoString(@"Beats amount (in the current timing point)"),
+                                    currentBeat = new InfoString(@"Current beat"),
+                                    beatsPerMinute = new InfoString(@"BPM"),
+                                    adjustedBeatLength = new InfoString(@"Adjusted beat length"),
+                                    timeUntilNextBeat = new InfoString(@"Time until next beat"),
+                                    timeSinceLastBeat = new InfoString(@"Time since last beat"),
+                                }
+                            }
+                        }
+                    },
+                    new Container
+                    {
+                        Name = @"Color indicator",
+                        Anchor = Anchor.BottomCentre,
+                        Origin = Anchor.BottomCentre,
+                        RelativeSizeAxes = Axes.X,
+                        Height = flash_layer_heigth,
+                        Children = new Drawable[]
+                        {
+                            new Box
+                            {
+                                RelativeSizeAxes = Axes.Both,
+                                Colour = Color4.Black,
+                            },
+                            flashLayer = new Box
+                            {
+                                RelativeSizeAxes = Axes.Both,
+                                Colour = Color4.White,
+                                Alpha = 0,
+                            }
+                        }
+                    }
+                };
+
+                Beatmap.ValueChanged += delegate
+                {
+                    timingPointCount.Value = 0;
+                    currentTimingPoint.Value = 0;
+                    beatCount.Value = 0;
+                    currentBeat.Value = 0;
+                    beatsPerMinute.Value = 0;
+                    adjustedBeatLength.Value = 0;
+                    timeUntilNextBeat.Value = 0;
+                    timeSinceLastBeat.Value = 0;
+                };
+            }
+
+            private SortedList<TimingControlPoint> timingPoints => Beatmap.Value.Beatmap.ControlPointInfo.TimingPoints;
+            private TimingControlPoint getNextTimingPoint(TimingControlPoint current)
+            {
+                if (timingPoints[timingPoints.Count - 1] == current)
+                    return current;
+
+                return timingPoints[timingPoints.IndexOf(current) + 1];
+            }
+
+            private int calculateBeatCount(TimingControlPoint current)
+            {
+                if (timingPoints[timingPoints.Count - 1] == current)
+                    return (int)Math.Ceiling((Beatmap.Value.Track.Length - current.Time) / current.BeatLength);
+
+                return (int)Math.Ceiling((getNextTimingPoint(current).Time - current.Time) / current.BeatLength);
+            }
+
+            protected override void Update()
+            {
+                base.Update();
+                timeUntilNextBeat.Value = TimeUntilNextBeat;
+                timeSinceLastBeat.Value = TimeSinceLastBeat;
+            }
+
+            protected override void OnNewBeat(int beatIndex, TimingControlPoint timingPoint, EffectControlPoint effectPoint, TrackAmplitudes amplitudes)
+            {
+                base.OnNewBeat(beatIndex, timingPoint, effectPoint, amplitudes);
+
+                timingPointCount.Value = timingPoints.Count;
+                currentTimingPoint.Value = timingPoints.IndexOf(timingPoint);
+                beatCount.Value = calculateBeatCount(timingPoint);
+                currentBeat.Value = beatIndex;
+                beatsPerMinute.Value = 60000 / timingPoint.BeatLength;
+                adjustedBeatLength.Value = timingPoint.BeatLength;
+
+                flashLayer.ClearTransforms();
+                flashLayer.FadeTo(1);
+                flashLayer.FadeTo(0, timingPoint.BeatLength);
+            }
+        }
+
+        private class InfoString : FillFlowContainer
+        {
+            private const int text_size = 20;
+            private const int margin = 7;
+
+            private readonly OsuSpriteText valueText;
+
+            public double Value
+            {
+                set { valueText.Text = $"{value:G}"; }
+            }
+
+            public InfoString(string header)
+            {
+                AutoSizeAxes = Axes.Both;
+                Direction = FillDirection.Horizontal;
+                Add(new OsuSpriteText { Text = header + @": ", TextSize = text_size });
+                Add(valueText = new OsuSpriteText() { TextSize = text_size });
+                Margin = new MarginPadding(margin);
+            }
+        }
+    }
+}

osu.Desktop.VisualTests/Tests/TestCaseContextMenu.cs

@@ -7,7 +7,6 @@ using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Cursor;
 using osu.Framework.Graphics.Shapes;
-using osu.Framework.Graphics.Transforms;
 using osu.Framework.Graphics.UserInterface;
 using osu.Framework.Testing;
 using osu.Game.Graphics.UserInterface;
@@ -21,10 +20,10 @@ namespace osu.Desktop.VisualTests.Tests
         private const int start_time = 0;
         private const int duration = 1000;
 
+        private readonly Container container;
+
         public TestCaseContextMenu()
         {
-            MyContextMenuContainer container;
-
             Add(container = new MyContextMenuContainer
             {
                 Size = new Vector2(200),
@@ -54,43 +53,26 @@ namespace osu.Desktop.VisualTests.Tests
                     }
                 }
             });
+        }
 
-            container.Transforms.Add(new TransformPosition
+        protected override void LoadComplete()
         {
-                StartValue = Vector2.Zero,
+            base.LoadComplete();
-                EndValue = new Vector2(0, 100),
+
-                StartTime = start_time,
+            using (container.BeginLoopedSequence())
-                EndTime = start_time + duration,
-                LoopCount = -1,
-                LoopDelay = duration * 3
-            });
-            container.Transforms.Add(new TransformPosition
             {
-                StartValue = new Vector2(0, 100),
+                container.MoveTo(new Vector2(0, 100), duration);
-                EndValue = new Vector2(100, 100),
+                using (container.BeginDelayedSequence(duration))
-                StartTime = start_time + duration,
-                EndTime = start_time + duration * 2,
-                LoopCount = -1,
-                LoopDelay = duration * 3
-            });
-            container.Transforms.Add(new TransformPosition
                 {
-                StartValue = new Vector2(100, 100),
+                    container.MoveTo(new Vector2(100, 100), duration);
-                EndValue = new Vector2(100, 0),
+                    using (container.BeginDelayedSequence(duration))
-                StartTime = start_time + duration * 2,
-                EndTime = start_time + duration * 3,
-                LoopCount = -1,
-                LoopDelay = duration * 3
-            });
-            container.Transforms.Add(new TransformPosition
                     {
-                StartValue = new Vector2(100, 0),
+                        container.MoveTo(new Vector2(100, 0), duration);
-                EndValue = Vector2.Zero,
+                        using (container.BeginDelayedSequence(duration))
-                StartTime = start_time + duration * 3,
+                            container.MoveTo(Vector2.Zero, duration);
-                EndTime = start_time + duration * 4,
+                    }
-                LoopCount = -1,
+                }
-                LoopDelay = duration * 3
+            }
-            });
         }
 
         private class MyContextMenuContainer : Container, IHasContextMenu

osu.Desktop.VisualTests/Tests/TestCaseGamefield.cs

@@ -76,7 +76,7 @@ namespace osu.Desktop.VisualTests.Tests
                 ControlPointInfo = controlPointInfo
             });
 
-            Add(new Drawable[]
+            AddRange(new Drawable[]
             {
                 new Container
                 {

osu.Desktop.VisualTests/Tests/TestCaseScoreCounter.cs

@@ -50,7 +50,7 @@ namespace osu.Desktop.VisualTests.Tests
                 Origin = Anchor.BottomLeft,
                 Anchor = Anchor.BottomLeft,
                 Position = new Vector2(20, -160),
-                Count = 5,
+                CountStars = 5,
             };
             Add(stars);
 
@@ -59,7 +59,7 @@ namespace osu.Desktop.VisualTests.Tests
                 Origin = Anchor.BottomLeft,
                 Anchor = Anchor.BottomLeft,
                 Position = new Vector2(20, -190),
-                Text = stars.Count.ToString("0.00"),
+                Text = stars.CountStars.ToString("0.00"),
             };
             Add(starsLabel);
 
@@ -69,8 +69,8 @@ namespace osu.Desktop.VisualTests.Tests
                 comboCounter.Current.Value = 0;
                 numerator = denominator = 0;
                 accuracyCounter.SetFraction(0, 0);
-                stars.Count = 0;
+                stars.CountStars = 0;
-                starsLabel.Text = stars.Count.ToString("0.00");
+                starsLabel.Text = stars.CountStars.ToString("0.00");
             });
 
             AddStep(@"Hit! :D", delegate
@@ -91,8 +91,8 @@ namespace osu.Desktop.VisualTests.Tests
 
             AddStep(@"Alter stars", delegate
             {
-                stars.Count = RNG.NextSingle() * (stars.StarCount + 1);
+                stars.CountStars = RNG.NextSingle() * (stars.StarCount + 1);
-                starsLabel.Text = stars.Count.ToString("0.00");
+                starsLabel.Text = stars.CountStars.ToString("0.00");
             });
 
             AddStep(@"Stop counters", delegate

osu.Desktop.VisualTests/Tests/TestCaseScrollingHitObjects.cs

@@ -55,7 +55,7 @@ namespace osu.Desktop.VisualTests.Tests
             timeRangeBindable.ValueChanged += v => timeRangeText.Text = $"Visible Range: {v:#,#.#}";
             timeRangeBindable.ValueChanged += v => bottomLabel.Text = $"t minus {v:#,#}";
 
-            Add(new Drawable[]
+            AddRange(new Drawable[]
             {
                 new Container
                 {

osu.Desktop.VisualTests/osu.Desktop.VisualTests.csproj

@@ -187,6 +187,7 @@
   <ItemGroup>
     <Compile Include="AutomatedVisualTestGame.cs" />
     <Compile Include="Program.cs" />
+    <Compile Include="Tests\TestCaseBeatSyncedContainer.cs" />
     <Compile Include="Tests\TestCaseChatDisplay.cs" />
     <Compile Include="Tests\TestCaseBeatmapDetails.cs" />
     <Compile Include="Tests\TestCaseContextMenu.cs" />

osu.Desktop/Overlays/VersionManager.cs

@@ -202,7 +202,7 @@ namespace osu.Desktop.Overlays
             {
                 this.game = game;
 
-                IconContent.Add(new Drawable[]
+                IconContent.AddRange(new Drawable[]
                 {
                     new Box
                     {

osu.Game.Rulesets.Catch/Objects/Drawable/DrawableFruit.cs

@@ -5,18 +5,17 @@ using osu.Framework.Allocation;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Sprites;
 using osu.Framework.Graphics.Textures;
-using osu.Framework.Graphics.Transforms;
 using OpenTK;
 
 namespace osu.Game.Rulesets.Catch.Objects.Drawable
 {
     internal class DrawableFruit : Sprite
     {
-        private readonly CatchBaseHit h;
+        //private readonly CatchBaseHit h;
 
         public DrawableFruit(CatchBaseHit h)
         {
-            this.h = h;
+            //this.h = h;
 
             Origin = Anchor.Centre;
             Scale = new Vector2(0.1f);
@@ -29,10 +28,8 @@ namespace osu.Game.Rulesets.Catch.Objects.Drawable
         {
             Texture = textures.Get(@"Menu/logo");
 
-            const double duration = 0;
+            //Transforms.Add(new TransformPosition { StartTime = h.StartTime - 200, EndTime = h.StartTime, StartValue = new Vector2(h.Position, -0.1f), EndValue = new Vector2(h.Position, 0.9f) });
-
+            //Transforms.Add(new TransformAlpha { StartTime = h.StartTime + duration + 200, EndTime = h.StartTime + duration + 400, StartValue = 1, EndValue = 0 });
-            Transforms.Add(new TransformPosition { StartTime = h.StartTime - 200, EndTime = h.StartTime, StartValue = new Vector2(h.Position, -0.1f), EndValue = new Vector2(h.Position, 0.9f) });
-            Transforms.Add(new TransformAlpha { StartTime = h.StartTime + duration + 200, EndTime = h.StartTime + duration + 400, StartValue = 1, EndValue = 0 });
             Expire(true);
         }
     }

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

@@ -42,7 +42,7 @@ namespace osu.Game.Rulesets.Mania.Objects.Drawables
             RelativeSizeAxes = Axes.Both;
             Height = (float)HitObject.Duration;
 
-            Add(new Drawable[]
+            AddRange(new Drawable[]
             {
                 // For now the body piece covers the entire height of the container
                 // whereas possibly in the future we don't want to extend under the head/tail.

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

@@ -235,7 +235,7 @@ namespace osu.Game.Rulesets.Mania.UI
 
         private void transformVisibleTimeRangeTo(double newTimeRange, double duration = 0, EasingTypes easing = EasingTypes.None)
         {
-            TransformTo(() => visibleTimeRange.Value, newTimeRange, duration, easing, new TransformTimeSpan());
+            TransformTo(newTimeRange, duration, easing, new TransformTimeSpan());
         }
 
         protected override void Update()
@@ -247,7 +247,7 @@ namespace osu.Game.Rulesets.Mania.UI
 
         private class TransformTimeSpan : Transform<double, Drawable>
         {
-            public override double CurrentValue
+            public double CurrentValue
             {
                 get
                 {
@@ -259,13 +259,8 @@ namespace osu.Game.Rulesets.Mania.UI
                 }
             }
 
-            public override void Apply(Drawable d)
+            public override void Apply(Drawable d) => ((ManiaPlayfield)d).visibleTimeRange.Value = (float)CurrentValue;
-            {
+            public override void ReadIntoStartValue(Drawable d) => StartValue = ((ManiaPlayfield)d).visibleTimeRange.Value;
-                base.Apply(d);
-
-                var p = (ManiaPlayfield)d;
-                p.visibleTimeRange.Value = (float)CurrentValue;
-            }
         }
     }
 }

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

@@ -90,10 +90,14 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
             base.UpdateInitialState();
 
             // sane defaults
-            ring.Alpha = circle.Alpha = number.Alpha = glow.Alpha = 1;
+            ring.Show();
-            ApproachCircle.Alpha = 0;
+            circle.Show();
-            ApproachCircle.Scale = new Vector2(4);
+            number.Show();
-            explode.Alpha = 0;
+            glow.Show();
+
+            ApproachCircle.Hide();
+            ApproachCircle.ScaleTo(new Vector2(4));
+            explode.Hide();
         }
 
         protected override void UpdatePreemptState()
@@ -106,36 +110,36 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
 
         protected override void UpdateCurrentState(ArmedState state)
         {
-            ApproachCircle.FadeOut();
+            double duration = ((HitObject as IHasEndTime)?.EndTime ?? HitObject.StartTime) - HitObject.StartTime;
 
-            double endTime = (HitObject as IHasEndTime)?.EndTime ?? HitObject.StartTime;
+            using (glow.BeginDelayedSequence(duration))
-            double duration = endTime - HitObject.StartTime;
-
-            glow.Delay(duration);
                 glow.FadeOut(400);
 
             switch (state)
             {
                 case ArmedState.Idle:
-                    Delay(duration + TIME_PREEMPT);
+                    using (BeginDelayedSequence(duration + TIME_PREEMPT))
                         FadeOut(TIME_FADEOUT);
                     Expire(true);
                     break;
                 case ArmedState.Miss:
+                    ApproachCircle.FadeOut(50);
                     FadeOut(TIME_FADEOUT / 5);
                     Expire();
                     break;
                 case ArmedState.Hit:
+                    ApproachCircle.FadeOut(50);
+
                     const double flash_in = 40;
 
                     flash.FadeTo(0.8f, flash_in);
-                    flash.Delay(flash_in);
+                    using (flash.BeginDelayedSequence(flash_in))
                         flash.FadeOut(100);
 
                     explode.FadeIn(flash_in);
 
-                    Delay(flash_in, true);
+                    using (BeginDelayedSequence(flash_in, true))
-
+                    {
                         //after the flash, we can hide some elements that were behind it
                         ring.FadeOut();
                         circle.FadeOut();
@@ -143,6 +147,8 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
 
                         FadeOut(800);
                         ScaleTo(Scale * 1.5f, 400, EasingTypes.OutQuad);
+                    }
+
                     Expire();
                     break;
             }

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

@@ -17,6 +17,7 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
             : base(hitObject)
         {
             AccentColour = HitObject.ComboColour;
+            Alpha = 0;
         }
 
         protected override OsuJudgement CreateJudgement() => new OsuJudgement { MaxScore = OsuScoreResult.Hit300 };
@@ -25,10 +26,10 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
         {
             Flush();
 
-            UpdateInitialState();
-
             using (BeginAbsoluteSequence(HitObject.StartTime - TIME_PREEMPT, true))
             {
+                UpdateInitialState();
+
                 UpdatePreemptState();
 
                 using (BeginDelayedSequence(TIME_PREEMPT + Judgement.TimeOffset, true))
@@ -36,8 +37,9 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
             }
         }
 
-        protected virtual void UpdateCurrentState(ArmedState state)
+        protected virtual void UpdateInitialState()
         {
+            Hide();
         }
 
         protected virtual void UpdatePreemptState()
@@ -45,9 +47,8 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
             FadeIn(TIME_FADEIN);
         }
 
-        protected virtual void UpdateInitialState()
+        protected virtual void UpdateCurrentState(ArmedState state)
         {
-            Alpha = 0;
         }
     }
 

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

@@ -37,8 +37,8 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables.Pieces
         protected override void LoadComplete()
         {
             base.LoadComplete();
+            using (icon.BeginLoopedSequence())
                 icon.RotateTo(360, 1000);
-            icon.Loop();
         }
 
         public void UpdateProgress(double progress, int repeat)

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

@@ -41,7 +41,7 @@ namespace osu.Game.Rulesets.Osu.UI
             Anchor = Anchor.Centre;
             Origin = Anchor.Centre;
 
-            Add(new Drawable[]
+            AddRange(new Drawable[]
             {
                 connectionLayer = new FollowPointRenderer
                 {

osu.Game.Rulesets.Taiko/Objects/Drawables/Pieces/CirclePiece.cs

@@ -68,7 +68,7 @@ namespace osu.Game.Rulesets.Taiko.Objects.Drawables.Pieces
         {
             EarlyActivationMilliseconds = pre_beat_transition_time;
 
-            AddInternal(new Drawable[]
+            AddRangeInternal(new Drawable[]
             {
                 background = new CircularContainer
                 {

osu.Game.Rulesets.Taiko/UI/TaikoPlayfield.cs

@@ -54,7 +54,7 @@ namespace osu.Game.Rulesets.Taiko.UI
 
         public TaikoPlayfield()
         {
-            AddInternal(new Drawable[]
+            AddRangeInternal(new Drawable[]
             {
                 new ScaleFixContainer
                 {

osu.Game.Tests/Beatmaps/IO/ImportBeatmapTest.cs

@@ -75,18 +75,16 @@ namespace osu.Game.Tests.Beatmaps.IO
 
                 var temp = prepareTempCopy(osz_path);
 
-                Assert.IsTrue(File.Exists(temp));
+                Assert.IsTrue(File.Exists(temp), "Temporary file copy never substantiated");
 
                 using (File.OpenRead(temp))
                     host.Dependencies.Get<BeatmapDatabase>().Import(temp);
 
                 ensureLoaded(host);
 
-                Assert.IsTrue(File.Exists(temp));
-
                 File.Delete(temp);
 
-                Assert.IsFalse(File.Exists(temp));
+                Assert.IsFalse(File.Exists(temp), "We likely held a read lock on the file when we shouldn't");
             }
         }
 
@@ -111,7 +109,7 @@ namespace osu.Game.Tests.Beatmaps.IO
             return osu;
         }
 
-        private void ensureLoaded(GameHost host, int timeout = 10000)
+        private void ensureLoaded(GameHost host, int timeout = 60000)
         {
             IEnumerable<BeatmapSetInfo> resultSets = null;
 

osu.Game/Beatmaps/Drawables/BeatmapPanel.cs

@@ -140,7 +140,7 @@ namespace osu.Game.Beatmaps.Drawables
                                 },
                                 starCounter = new StarCounter
                                 {
-                                    Count = (float)beatmap.StarDifficulty,
+                                    CountStars = (float)beatmap.StarDifficulty,
                                     Scale = new Vector2(0.8f),
                                 }
                             }

osu.Game/Beatmaps/Drawables/BeatmapSetHeader.cs

@@ -93,6 +93,7 @@ namespace osu.Game.Beatmaps.Drawables
                 {
                     new BeatmapBackgroundSprite(working)
                     {
+                        RelativeSizeAxes = Axes.Both,
                         Anchor = Anchor.Centre,
                         Origin = Anchor.Centre,
                         FillMode = FillMode.Fill,

osu.Game/Graphics/Backgrounds/Background.cs

@@ -26,6 +26,7 @@ namespace osu.Game.Graphics.Backgrounds
 
             Add(Sprite = new Sprite
             {
+                RelativeSizeAxes = Axes.Both,
                 Anchor = Anchor.Centre,
                 Origin = Anchor.Centre,
                 Colour = Color4.DarkGray,

osu.Game/Graphics/Containers/BeatSyncedContainer.cs

@@ -23,6 +23,16 @@ namespace osu.Game.Graphics.Containers
         /// </summary>
         protected double EarlyActivationMilliseconds;
 
+        /// <summary>
+        /// The time in milliseconds until the next beat.
+        /// </summary>
+        public double TimeUntilNextBeat { get; private set; }
+
+        /// <summary>
+        /// The time in milliseconds since the last beat
+        /// </summary>
+        public double TimeSinceLastBeat { get; private set; }
+
         protected override void Update()
         {
             if (Beatmap.Value?.Track == null)
@@ -42,12 +52,16 @@ namespace osu.Game.Graphics.Containers
             if (currentTrackTime < timingPoint.Time)
                 beatIndex--;
 
+            TimeUntilNextBeat = (timingPoint.Time - currentTrackTime) % timingPoint.BeatLength;
+            if (TimeUntilNextBeat < 0)
+                TimeUntilNextBeat += timingPoint.BeatLength;
+
+            TimeSinceLastBeat = timingPoint.BeatLength - TimeUntilNextBeat;
+
             if (timingPoint == lastTimingPoint && beatIndex == lastBeat)
                 return;
 
-            double offsetFromBeat = (timingPoint.Time - currentTrackTime) % timingPoint.BeatLength;
+            using (BeginDelayedSequence(-TimeSinceLastBeat, true))
-
-            using (BeginDelayedSequence(offsetFromBeat, true))
                 OnNewBeat(beatIndex, timingPoint, effectPoint, Beatmap.Value.Track.CurrentAmplitudes);
 
             lastBeat = beatIndex;

osu.Game/Graphics/Containers/ReverseChildIDFillFlowContainer.cs

@@ -8,9 +8,10 @@ using osu.Framework.Graphics.Containers;
 
 namespace osu.Game.Graphics.Containers
 {
-    public class ReverseDepthFillFlowContainer<T> : FillFlowContainer<T> where T : Drawable
+    public class ReverseChildIDFillFlowContainer<T> : FillFlowContainer<T> where T : Drawable
     {
-        protected override IComparer<Drawable> DepthComparer => new ReverseCreationOrderDepthComparer();
+        protected override int Compare(Drawable x, Drawable y) => CompareReverseChildID(x, y);
+
         protected override IEnumerable<Drawable> FlowingChildren => base.FlowingChildren.Reverse();
     }
 }

osu.Game/Graphics/Containers/SectionsContainer.cs

@@ -93,7 +93,7 @@ namespace osu.Game.Graphics.Containers
                 sections = value.ToList();
                 if (sections.Count == 0) return;
 
-                sectionsContainer.Add(sections);
+                sectionsContainer.AddRange(sections);
                 SelectedSection.Value = sections[0];
                 lastKnownScroll = float.NaN;
             }

osu.Game/Graphics/IHasAccentColour.cs

@@ -30,7 +30,7 @@ namespace osu.Game.Graphics
         public static void FadeAccent<T>(this T accentedDrawable, Color4 newColour, double duration = 0, EasingTypes easing = EasingTypes.None)
             where T : Transformable<Drawable>, IHasAccentColour
         {
-            accentedDrawable.TransformTo(() => accentedDrawable.AccentColour, newColour, duration, easing, new TransformAccent());
+            accentedDrawable.TransformTo(newColour, duration, easing, new TransformAccent());
         }
     }
 }

osu.Game/Graphics/Transforms/TransformAccent.cs

@@ -13,7 +13,7 @@ namespace osu.Game.Graphics.Transforms
         /// <summary>
         /// Current value of the transformed colour in linear colour space.
         /// </summary>
-        public override Color4 CurrentValue
+        public virtual Color4 CurrentValue
         {
             get
             {
@@ -25,13 +25,7 @@ namespace osu.Game.Graphics.Transforms
             }
         }
 
-        public override void Apply(Drawable d)
+        public override void Apply(Drawable d) => ((IHasAccentColour)d).AccentColour = CurrentValue;
-        {
+        public override void ReadIntoStartValue(Drawable d) => StartValue = ((IHasAccentColour)d).AccentColour;
-            base.Apply(d);
-
-            var accented = d as IHasAccentColour;
-            if (accented != null)
-                accented.AccentColour = CurrentValue;
-        }
     }
 }

osu.Game/Graphics/UserInterface/BarGraph.cs

@@ -58,7 +58,7 @@ namespace osu.Game.Graphics.UserInterface
                             Direction = Direction,
                         });
                 //I'm using ToList() here because Where() returns an Enumerable which can change it's elements afterwards
-                Remove(Children.Where((bar, index) => index >= value.Count()).ToList());
+                RemoveRange(Children.Where((bar, index) => index >= value.Count()).ToList());
             }
         }
     }

osu.Game/Graphics/UserInterface/LoadingAnimation.cs

@@ -34,9 +34,8 @@ namespace osu.Game.Graphics.UserInterface
         {
             base.LoadComplete();
 
+            using (spinner.BeginLoopedSequence())
                 spinner.RotateTo(360, 2000);
-            using (spinner.BeginDelayedSequence(2000))
-                spinner.Loop();
         }
 
         private const float transition_duration = 500;

osu.Game/Graphics/UserInterface/OsuButton.cs

@@ -49,7 +49,7 @@ namespace osu.Game.Graphics.UserInterface
             Content.Masking = true;
             Content.CornerRadius = 5;
 
-            Add(new Drawable[]
+            AddRange(new Drawable[]
             {
                 new Triangles
                 {

osu.Game/Graphics/UserInterface/PercentageCounter.cs

@@ -47,7 +47,7 @@ namespace osu.Game.Graphics.UserInterface
 
         protected class TransformAccuracy : Transform<double, Drawable>
         {
-            public override double CurrentValue
+            public virtual double CurrentValue
             {
                 get
                 {
@@ -59,11 +59,8 @@ namespace osu.Game.Graphics.UserInterface
                 }
             }
 
-            public override void Apply(Drawable d)
+            public override void Apply(Drawable d) => ((PercentageCounter)d).DisplayedCount = CurrentValue;
-            {
+            public override void ReadIntoStartValue(Drawable d) => StartValue = ((PercentageCounter)d).DisplayedCount;
-                base.Apply(d);
-                ((PercentageCounter)d).DisplayedCount = CurrentValue;
-            }
         }
     }
 }

osu.Game/Graphics/UserInterface/RollingCounter.cs

@@ -210,7 +210,6 @@ namespace osu.Game.Graphics.UserInterface
 
             transform.StartTime = TransformStartTime;
             transform.EndTime = TransformStartTime + rollingTotalDuration;
-            transform.StartValue = currentValue;
             transform.EndValue = newValue;
             transform.Easing = RollingEasing;
 

osu.Game/Graphics/UserInterface/ScoreCounter.cs

@@ -58,7 +58,7 @@ namespace osu.Game.Graphics.UserInterface
 
         protected class TransformScore : Transform<double, Drawable>
         {
-            public override double CurrentValue
+            public virtual double CurrentValue
             {
                 get
                 {
@@ -70,11 +70,8 @@ namespace osu.Game.Graphics.UserInterface
                 }
             }
 
-            public override void Apply(Drawable d)
+            public override void Apply(Drawable d) => ((ScoreCounter)d).DisplayedCount = CurrentValue;
-            {
+            public override void ReadIntoStartValue(Drawable d) => StartValue = ((ScoreCounter)d).DisplayedCount;
-                base.Apply(d);
-                ((ScoreCounter)d).DisplayedCount = CurrentValue;
-            }
         }
     }
 }

osu.Game/Graphics/UserInterface/SearchTextBox.cs

@@ -17,7 +17,7 @@ namespace osu.Game.Graphics.UserInterface
         public SearchTextBox()
         {
             Height = 35;
-            Add(new Drawable[]
+            AddRange(new Drawable[]
             {
                 new TextAwesome
                 {

osu.Game/Graphics/UserInterface/SimpleComboCounter.cs

@@ -39,7 +39,7 @@ namespace osu.Game.Graphics.UserInterface
 
         private class TransformCounterCount : Transform<int, Drawable>
         {
-            public override int CurrentValue
+            public int CurrentValue
             {
                 get
                 {
@@ -51,11 +51,8 @@ namespace osu.Game.Graphics.UserInterface
                 }
             }
 
-            public override void Apply(Drawable d)
+            public override void Apply(Drawable d) => ((SimpleComboCounter)d).DisplayedCount = CurrentValue;
-            {
+            public override void ReadIntoStartValue(Drawable d) => StartValue = ((SimpleComboCounter)d).DisplayedCount;
-                base.Apply(d);
-                ((SimpleComboCounter)d).DisplayedCount = CurrentValue;
-            }
         }
     }
 }

osu.Game/Graphics/UserInterface/StarCounter.cs

@@ -33,25 +33,25 @@ namespace osu.Game.Graphics.UserInterface
         private const float star_size = 20;
         private const float star_spacing = 4;
 
-        private float count;
+        private float countStars;
 
         /// <summary>
         /// Amount of stars represented.
         /// </summary>
-        public float Count
+        public float CountStars
         {
             get
             {
-                return count;
+                return countStars;
             }
 
             set
             {
-                if (count == value) return;
+                if (countStars == value) return;
 
                 if (IsLoaded)
                     transformCount(value);
-                count = value;
+                countStars = value;
             }
         }
 
@@ -94,15 +94,15 @@ namespace osu.Game.Graphics.UserInterface
 
         public void ResetCount()
         {
-            count = 0;
+            countStars = 0;
             StopAnimation();
         }
 
         public void ReplayAnimation()
         {
-            var t = count;
+            var t = countStars;
             ResetCount();
-            Count = t;
+            CountStars = t;
         }
 
         public void StopAnimation()
@@ -111,8 +111,8 @@ namespace osu.Game.Graphics.UserInterface
             foreach (var star in stars.Children)
             {
                 star.ClearTransforms(true);
-                star.FadeTo(i < count ? 1.0f : minStarAlpha);
+                star.FadeTo(i < countStars ? 1.0f : minStarAlpha);
-                star.Icon.ScaleTo(getStarScale(i, count));
+                star.Icon.ScaleTo(getStarScale(i, countStars));
                 i++;
             }
         }
@@ -132,7 +132,7 @@ namespace osu.Game.Graphics.UserInterface
             {
                 star.ClearTransforms(true);
 
-                var delay = (count <= newValue ? Math.Max(i - count, 0) : Math.Max(count - 1 - i, 0)) * animationDelay;
+                var delay = (countStars <= newValue ? Math.Max(i - countStars, 0) : Math.Max(countStars - 1 - i, 0)) * animationDelay;
 
                 using (BeginDelayedSequence(delay, true))
                 {

osu.Game/OsuGame.cs

@@ -141,7 +141,7 @@ namespace osu.Game
         {
             base.LoadComplete();
 
-            Add(new Drawable[] {
+            AddRange(new Drawable[] {
                 new VolumeControlReceptor
                 {
                     RelativeSizeAxes = Axes.Both,

osu.Game/Overlays/Chat/DrawableChannel.cs

@@ -67,7 +67,7 @@ namespace osu.Game.Overlays.Chat
             var displayMessages = newMessages.Skip(Math.Max(0, newMessages.Count() - Channel.MAX_HISTORY));
 
             //up to last Channel.MAX_HISTORY messages
-            flow.Add(displayMessages.Select(m => new ChatLine(m)));
+            flow.AddRange(displayMessages.Select(m => new ChatLine(m)));
 
             if (!IsLoaded) return;
 

osu.Game/Overlays/Direct/DirectPanel.cs

@@ -38,6 +38,7 @@ namespace osu.Game.Overlays.Direct
         {
             return new AsyncLoadWrapper(new BeatmapBackgroundSprite(new OnlineWorkingBeatmap(SetInfo.Beatmaps.FirstOrDefault(), textures, null))
             {
+                RelativeSizeAxes = Axes.Both,
                 FillMode = FillMode.Fill,
                 OnLoadComplete = d => d.FadeInFromZero(400, EasingTypes.Out),
             }) { RelativeSizeAxes = Axes.Both };

osu.Game/Overlays/DragBar.cs

@@ -75,7 +75,7 @@ namespace osu.Game.Overlays
         private void updatePosition(float position, bool easing = true)
         {
             position = MathHelper.Clamp(position, 0, 1);
-            Fill.TransformTo(() => Fill.Width, position, easing ? 200 : 0, EasingTypes.OutQuint, new TransformSeek());
+            Fill.TransformTo(position, easing ? 200 : 0, EasingTypes.OutQuint, new TransformSeek());
         }
 
         protected override bool OnMouseDown(InputState state, MouseDownEventArgs args)
@@ -100,11 +100,8 @@ namespace osu.Game.Overlays
 
         private class TransformSeek : TransformFloat<Drawable>
         {
-            public override void Apply(Drawable d)
+            public override void Apply(Drawable d) => d.Width = CurrentValue;
-            {
+            public override void ReadIntoStartValue(Drawable d) => StartValue = d.Width;
-                base.Apply(d);
-                d.Width = CurrentValue;
-            }
         }
     }
 }

osu.Game/Overlays/Mods/ModButton.cs

@@ -199,7 +199,7 @@ namespace osu.Game.Overlays.Mods
             iconsContainer.Clear();
             if (Mods.Length > 1)
             {
-                iconsContainer.Add(new[]
+                iconsContainer.AddRange(new[]
                 {
                     backgroundIcon = new ModIcon(Mods[1])
                     {

osu.Game/Overlays/MusicController.cs

@@ -398,6 +398,7 @@ namespace osu.Game.Overlays
                 {
                     sprite = new Sprite
                     {
+                        RelativeSizeAxes = Axes.Both,
                         Colour = OsuColour.Gray(150),
                         FillMode = FillMode.Fill,
                     },

osu.Game/Overlays/Notifications/Notification.cs

@@ -7,7 +7,6 @@ using osu.Framework.Extensions.Color4Extensions;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Colour;
 using osu.Framework.Graphics.Containers;
-using osu.Framework.Graphics.Transforms;
 using osu.Framework.Input;
 using osu.Game.Graphics;
 using OpenTK;
@@ -50,7 +49,7 @@ namespace osu.Game.Overlays.Notifications
             RelativeSizeAxes = Axes.X;
             AutoSizeAxes = Axes.Y;
 
-            AddInternal(new Drawable[]
+            AddRangeInternal(new Drawable[]
             {
                 Light = new NotificationLight
                 {
@@ -203,6 +202,8 @@ namespace osu.Game.Overlays.Notifications
                 get { return pulsate; }
                 set
                 {
+                    if (pulsate == value) return;
+
                     pulsate = value;
 
                     pulsateLayer.ClearTransforms();
@@ -211,25 +212,12 @@ namespace osu.Game.Overlays.Notifications
                     if (pulsate)
                     {
                         const float length = 1000;
-                        pulsateLayer.Transforms.Add(new TransformAlpha
+                        using (pulsateLayer.BeginLoopedSequence(length / 2))
                         {
-                            StartTime = Time.Current,
+                            pulsateLayer.FadeTo(0.4f, length, EasingTypes.In);
-                            EndTime = Time.Current + length,
+                            using (pulsateLayer.BeginDelayedSequence(length))
-                            StartValue = 1,
+                                pulsateLayer.FadeTo(1, length, EasingTypes.Out);
-                            EndValue = 0.4f,
+                        }
-                            Easing = EasingTypes.In
-                        });
-                        pulsateLayer.Transforms.Add(new TransformAlpha
-                        {
-                            StartTime = Time.Current + length,
-                            EndTime = Time.Current + length * 2,
-                            StartValue = 0.4f,
-                            EndValue = 1,
-                            Easing = EasingTypes.Out
-                        });
-
-                        //todo: figure why we can't add arbitrary delays at the end of loop.
-                        pulsateLayer.Loop(length * 2);
                     }
                 }
             }

osu.Game/Overlays/Notifications/NotificationSection.cs

@@ -69,7 +69,7 @@ namespace osu.Game.Overlays.Notifications
                 Left = 20,
             };
 
-            AddInternal(new Drawable[]
+            AddRangeInternal(new Drawable[]
             {
                 new Container
                 {

osu.Game/Overlays/Notifications/SimpleNotification.cs

@@ -42,7 +42,7 @@ namespace osu.Game.Overlays.Notifications
 
         public SimpleNotification()
         {
-            IconContent.Add(new Drawable[]
+            IconContent.AddRange(new Drawable[]
             {
                 IconBackgound = new Box
                 {

osu.Game/Overlays/OnScreenDisplay.cs

@@ -260,8 +260,6 @@ namespace osu.Game.Overlays
                     Radius = 8,
                 };
 
-                FadeEdgeEffectTo(0);
-
                 updateGlow();
                 Flush(true);
             }

osu.Game/Overlays/Settings/SettingsSection.cs

@@ -44,7 +44,7 @@ namespace osu.Game.Overlays.Settings
             const int header_size = 26;
             const int header_margin = 25;
             const int border_size = 2;
-            AddInternal(new Drawable[]
+            AddRangeInternal(new Drawable[]
             {
                 new Box
                 {

osu.Game/Overlays/Settings/SettingsSubsection.cs

@@ -33,7 +33,7 @@ namespace osu.Game.Overlays.Settings
             RelativeSizeAxes = Axes.X;
             AutoSizeAxes = Axes.Y;
             Direction = FillDirection.Vertical;
-            AddInternal(new Drawable[]
+            AddRangeInternal(new Drawable[]
             {
                 new OsuSpriteText
                 {

osu.Game/Overlays/SettingsOverlay.cs

@@ -93,7 +93,7 @@ namespace osu.Game.Overlays
                         new SidebarButton
                         {
                             Section = section,
-                            Action = sectionsContainer.ScrollContainer.ScrollIntoView,
+                            Action = b => sectionsContainer.ScrollContainer.ScrollTo(b),
                         }
                     ).ToArray()
                 }

osu.Game/Rulesets/Objects/HitObjectStartTimeComparer.cs

@@ -1,55 +0,0 @@
-// Copyright (c) 2007-2017 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.Game.Rulesets.Objects.Drawables;
-
-namespace osu.Game.Rulesets.Objects
-{
-    /// <summary>
-    /// Compares two hit objects by their start time, falling back to creation order if their start time is equal.
-    /// </summary>
-    public class HitObjectStartTimeComparer : Drawable.CreationOrderDepthComparer
-    {
-        public override int Compare(Drawable x, Drawable y)
-        {
-            var hitObjectX = x as DrawableHitObject;
-            var hitObjectY = y as DrawableHitObject;
-
-            // If either of the two drawables are not hit objects, fall back to the base comparer
-            if (hitObjectX?.HitObject == null || hitObjectY?.HitObject == null)
-                return base.Compare(x, y);
-
-            // Compare by start time
-            int i = hitObjectX.HitObject.StartTime.CompareTo(hitObjectY.HitObject.StartTime);
-            if (i != 0)
-                return i;
-
-            return base.Compare(x, y);
-        }
-    }
-
-    /// <summary>
-    /// Compares two hit objects by their start time, falling back to creation order if their start time is equal.
-    /// This will compare the two hit objects in reverse order.
-    /// </summary>
-    public class HitObjectReverseStartTimeComparer : Drawable.ReverseCreationOrderDepthComparer
-    {
-        public override int Compare(Drawable x, Drawable y)
-        {
-            var hitObjectX = x as DrawableHitObject;
-            var hitObjectY = y as DrawableHitObject;
-
-            // If either of the two drawables are not hit objects, fall back to the base comparer
-            if (hitObjectX?.HitObject == null || hitObjectY?.HitObject == null)
-                return base.Compare(x, y);
-
-            // Compare by start time
-            int i = hitObjectY.HitObject.StartTime.CompareTo(hitObjectX.HitObject.StartTime);
-            if (i != 0)
-                return i;
-
-            return base.Compare(x, y);
-        }
-    }
-}

osu.Game/Rulesets/Timing/DrawableTimingSection.cs

@@ -1,13 +1,11 @@
 // Copyright (c) 2007-2017 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.Linq;
 using osu.Framework.Caching;
 using osu.Framework.Configuration;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
-using osu.Game.Rulesets.Objects;
 using osu.Game.Rulesets.Objects.Drawables;
 using OpenTK;
 using osu.Game.Rulesets.Objects.Types;
@@ -55,7 +53,22 @@ namespace osu.Game.Rulesets.Timing
         /// </summary>
         internal MultiplierControlPoint ControlPoint;
 
-        protected override IComparer<Drawable> DepthComparer => new HitObjectReverseStartTimeComparer();
+        protected override int Compare(Drawable x, Drawable y)
+        {
+            var xHitObject = x as DrawableHitObject;
+            var yHitObject = y as DrawableHitObject;
+
+            // If either of the two drawables are not hit objects, fall back to the base comparer
+            if (xHitObject?.HitObject == null || yHitObject?.HitObject == null)
+                return base.Compare(x, y);
+
+            // Compare by start time
+            int i = yHitObject.HitObject.StartTime.CompareTo(xHitObject.HitObject.StartTime);
+            if (i != 0)
+                return i;
+
+            return base.Compare(x, y);
+        }
 
         /// <summary>
         /// Creates a new <see cref="DrawableTimingSection"/>.

osu.Game/Rulesets/Timing/SpeedAdjustmentCollection.cs

@@ -33,7 +33,20 @@ namespace osu.Game.Rulesets.Timing
             set { visibleTimeRange.BindTo(value); }
         }
 
-        protected override IComparer<Drawable> DepthComparer => new SpeedAdjustmentContainerReverseStartTimeComparer();
+        protected override int Compare(Drawable x, Drawable y)
+        {
+            var xSpeedAdjust = x as SpeedAdjustmentContainer;
+            var ySpeedAdjust = y as SpeedAdjustmentContainer;
+
+            // If either of the two drawables are not hit objects, fall back to the base comparer
+            if (xSpeedAdjust?.ControlPoint == null || ySpeedAdjust?.ControlPoint == null)
+                return CompareReverseChildID(x, y);
+
+            // Compare by start time
+            int i = ySpeedAdjust.ControlPoint.StartTime.CompareTo(xSpeedAdjust.ControlPoint.StartTime);
+
+            return i != 0 ? i : CompareReverseChildID(x, y);
+        }
 
         /// <summary>
         /// Hit objects that are to be re-processed on the next update.
@@ -116,27 +129,5 @@ namespace osu.Game.Rulesets.Timing
         /// <param name="time">The time to find the active <see cref="SpeedAdjustmentContainer"/> at.</param>
         /// <returns>The <see cref="SpeedAdjustmentContainer"/> active at <paramref name="time"/>. Null if there are no speed adjustments.</returns>
         private SpeedAdjustmentContainer adjustmentContainerAt(double time) => Children.FirstOrDefault(c => c.CanContain(time)) ?? Children.LastOrDefault();
-
-        /// <summary>
-        /// Compares two speed adjustment containers by their control point start time, falling back to creation order
-        // if their control point start time is equal. This will compare the two speed adjustment containers in reverse order.
-        /// </summary>
-        private class SpeedAdjustmentContainerReverseStartTimeComparer : ReverseCreationOrderDepthComparer
-        {
-            public override int Compare(Drawable x, Drawable y)
-            {
-                var speedAdjustmentX = x as SpeedAdjustmentContainer;
-                var speedAdjustmentY = y as SpeedAdjustmentContainer;
-
-                // If either of the two drawables are not hit objects, fall back to the base comparer
-                if (speedAdjustmentX?.ControlPoint == null || speedAdjustmentY?.ControlPoint == null)
-                    return base.Compare(x, y);
-
-                // Compare by start time
-                int i = speedAdjustmentY.ControlPoint.StartTime.CompareTo(speedAdjustmentX.ControlPoint.StartTime);
-
-                return i != 0 ? i : base.Compare(x, y);
-            }
-        }
     }
 }

osu.Game/Screens/Menu/Button.cs

@@ -9,7 +9,6 @@ using osu.Framework.Audio.Sample;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Shapes;
-using osu.Framework.Graphics.Transforms;
 using osu.Framework.Input;
 using osu.Game.Graphics;
 using osu.Game.Graphics.Sprites;
@@ -17,6 +16,9 @@ using OpenTK;
 using OpenTK.Graphics;
 using OpenTK.Input;
 using osu.Framework.Extensions.Color4Extensions;
+using osu.Game.Graphics.Containers;
+using osu.Framework.Audio.Track;
+using osu.Game.Beatmaps.ControlPoints;
 
 namespace osu.Game.Screens.Menu
 {
@@ -24,7 +26,7 @@ namespace osu.Game.Screens.Menu
     /// Button designed specifically for the osu!next main menu.
     /// In order to correctly flow, we have to use a negative margin on the parent container (due to the parallelogram shape).
     /// </summary>
-    public class Button : Container, IStateful<ButtonState>
+    public class Button : BeatSyncedContainer, IStateful<ButtonState>
     {
         private readonly Container iconText;
         private readonly Container box;
@@ -117,6 +119,27 @@ namespace osu.Game.Screens.Menu
             };
         }
 
+        protected override void OnNewBeat(int beatIndex, TimingControlPoint timingPoint, EffectControlPoint effectPoint, TrackAmplitudes amplitudes)
+        {
+            base.OnNewBeat(beatIndex, timingPoint, effectPoint, amplitudes);
+
+            if (!IsHovered) return;
+
+            bool rightward = beatIndex % 2 == 1;
+            double duration = timingPoint.BeatLength / 2;
+
+            icon.RotateTo(rightward ? 10 : -10, duration * 2, EasingTypes.InOutSine);
+
+            icon.MoveToY(-10, duration, EasingTypes.Out);
+            icon.ScaleTo(Vector2.One, duration, EasingTypes.Out);
+
+            using (icon.BeginDelayedSequence(duration))
+            {
+                icon.MoveToY(0, duration, EasingTypes.In);
+                icon.ScaleTo(new Vector2(1, 0.9f), duration, EasingTypes.In);
+            }
+        }
+
         protected override bool OnHover(InputState state)
         {
             if (State != ButtonState.Expanded) return true;
@@ -125,85 +148,11 @@ namespace osu.Game.Screens.Menu
 
             box.ScaleTo(new Vector2(1.5f, 1), 500, EasingTypes.OutElastic);
 
-            int duration = 0; //(int)(Game.Audio.BeatLength / 2);
+            double duration = TimeUntilNextBeat;
-            if (duration == 0) duration = 250;
 
             icon.ClearTransforms();
-
+            icon.RotateTo(10, duration, EasingTypes.InOutSine);
-            icon.ScaleTo(1, 500, EasingTypes.OutElasticHalf);
+            icon.ScaleTo(new Vector2(1, 0.9f), duration, EasingTypes.Out);
-
-            const double offset = 0; //(1 - Game.Audio.SyncBeatProgress) * duration;
-            double startTime = Time.Current + offset;
-
-            icon.RotateTo(10, offset, EasingTypes.InOutSine);
-            icon.ScaleTo(new Vector2(1, 0.9f), offset, EasingTypes.Out);
-
-            icon.Transforms.Add(new TransformRotation
-            {
-                StartValue = -10,
-                EndValue = 10,
-                StartTime = startTime,
-                EndTime = startTime + duration * 2,
-                Easing = EasingTypes.InOutSine,
-                LoopCount = -1,
-                LoopDelay = duration * 2
-            });
-
-            icon.Transforms.Add(new TransformPosition
-            {
-                StartValue = Vector2.Zero,
-                EndValue = new Vector2(0, -10),
-                StartTime = startTime,
-                EndTime = startTime + duration,
-                Easing = EasingTypes.Out,
-                LoopCount = -1,
-                LoopDelay = duration
-            });
-
-            icon.Transforms.Add(new TransformScale
-            {
-                StartValue = new Vector2(1, 0.9f),
-                EndValue = Vector2.One,
-                StartTime = startTime,
-                EndTime = startTime + duration,
-                Easing = EasingTypes.Out,
-                LoopCount = -1,
-                LoopDelay = duration
-            });
-
-            icon.Transforms.Add(new TransformPosition
-            {
-                StartValue = new Vector2(0, -10),
-                EndValue = Vector2.Zero,
-                StartTime = startTime + duration,
-                EndTime = startTime + duration * 2,
-                Easing = EasingTypes.In,
-                LoopCount = -1,
-                LoopDelay = duration
-            });
-
-            icon.Transforms.Add(new TransformScale
-            {
-                StartValue = Vector2.One,
-                EndValue = new Vector2(1, 0.9f),
-                StartTime = startTime + duration,
-                EndTime = startTime + duration * 2,
-                Easing = EasingTypes.In,
-                LoopCount = -1,
-                LoopDelay = duration
-            });
-
-            icon.Transforms.Add(new TransformRotation
-            {
-                StartValue = 10,
-                EndValue = -10,
-                StartTime = startTime + duration * 2,
-                EndTime = startTime + duration * 4,
-                Easing = EasingTypes.InOutSine,
-                LoopCount = -1,
-                LoopDelay = duration * 2
-            });
-
             return true;
         }
 
@@ -212,7 +161,6 @@ namespace osu.Game.Screens.Menu
             icon.ClearTransforms();
             icon.RotateTo(0, 500, EasingTypes.Out);
             icon.MoveTo(Vector2.Zero, 500, EasingTypes.Out);
-            icon.ScaleTo(0.7f, 500, EasingTypes.OutElasticHalf);
             icon.ScaleTo(Vector2.One, 200, EasingTypes.Out);
 
             if (State == ButtonState.Expanded)

osu.Game/Screens/Menu/ButtonSystem.cs

@@ -114,8 +114,8 @@ namespace osu.Game.Screens.Menu
             buttonsTopLevel.Add(new Button(@"osu!direct", string.Empty, FontAwesome.fa_osu_chevron_down_o, new Color4(165, 204, 0, 255), () => OnDirect?.Invoke(), 0, Key.D));
             buttonsTopLevel.Add(new Button(@"exit", string.Empty, FontAwesome.fa_osu_cross_o, new Color4(238, 51, 153, 255), onExit, 0, Key.Q));
 
-            buttonFlow.Add(buttonsPlay);
+            buttonFlow.AddRange(buttonsPlay);
-            buttonFlow.Add(buttonsTopLevel);
+            buttonFlow.AddRange(buttonsTopLevel);
         }
 
         [BackgroundDependencyLoader(true)]
@@ -213,6 +213,13 @@ namespace osu.Game.Screens.Menu
                 backButton.ContractStyle = 0;
                 settingsButton.ContractStyle = 0;
 
+                bool fromInitial = lastState == MenuState.Initial;
+
+                if (state == MenuState.TopLevel)
+                    buttonArea.Flush(true);
+
+                using (buttonArea.BeginDelayedSequence(fromInitial ? 150 : 0, true))
+                {
                     switch (state)
                     {
                         case MenuState.Exit:
@@ -222,9 +229,11 @@ namespace osu.Game.Screens.Menu
                             buttonAreaBackground.ScaleTo(Vector2.One, 500, EasingTypes.Out);
                             buttonArea.FadeOut(300);
 
-                        osuLogo.Delay(150);
+                            using (osuLogo.BeginDelayedSequence(150))
+                            {
                                 osuLogo.MoveTo(Vector2.Zero, 800, EasingTypes.OutExpo);
                                 osuLogo.ScaleTo(1, 800, EasingTypes.OutExpo);
+                            }
 
                             foreach (Button b in buttonsTopLevel)
                                 b.State = ButtonState.Contracted;
@@ -241,23 +250,17 @@ namespace osu.Game.Screens.Menu
                                 sampleBack?.Play();
                             break;
                         case MenuState.TopLevel:
-                        buttonArea.Flush(true);
-
                             buttonAreaBackground.ScaleTo(Vector2.One, 200, EasingTypes.Out);
 
+                            osuLogo.ClearTransforms();
                             osuLogo.MoveTo(buttonFlow.DrawPosition, 200, EasingTypes.In);
                             osuLogo.ScaleTo(0.5f, 200, EasingTypes.In);
 
                             buttonArea.FadeIn(300);
 
-                        if (lastState == MenuState.Initial)
+                            if (fromInitial && osuLogo.Scale.X > 0.5f)
-                        {
-                            buttonArea.Delay(150, true);
-
-                            if (osuLogo.Scale.X > 0.5f)
                                 using (osuLogo.BeginDelayedSequence(200, true))
                                     osuLogo.Impact();
-                        }
 
                             Scheduler.AddDelayed(() => toolbar?.Show(), 150);
 
@@ -292,9 +295,7 @@ namespace osu.Game.Screens.Menu
 
                     backButton.State = state == MenuState.Play ? ButtonState.Expanded : ButtonState.Contracted;
                     settingsButton.State = state == MenuState.TopLevel ? ButtonState.Expanded : ButtonState.Contracted;
-
+                }
-                if (lastState == MenuState.Initial)
-                    buttonArea.DelayReset();
             }
         }
 

osu.Game/Screens/Menu/FlowContainerWithOrigin.cs

@@ -20,7 +20,7 @@ namespace osu.Game.Screens.Menu
         /// </summary>
         public Drawable CentreTarget;
 
-        protected override IComparer<Drawable> DepthComparer => new ReverseCreationOrderDepthComparer();
+        protected override int Compare(Drawable x, Drawable y) => CompareReverseChildID(x, y);
 
         protected override IEnumerable<Drawable> FlowingChildren => base.FlowingChildren.Reverse();
 

osu.Game/Screens/Multiplayer/RoomInspector.cs

@@ -438,6 +438,7 @@ namespace osu.Game.Screens.Multiplayer
                 {
                     new AsyncLoadWrapper(new BeatmapBackgroundSprite(new OnlineWorkingBeatmap(value, textures, null))
                     {
+                        RelativeSizeAxes = Axes.Both,
                         Anchor = Anchor.Centre,
                         Origin = Anchor.Centre,
                         FillMode = FillMode.Fill,

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

@@ -198,7 +198,6 @@ namespace osu.Game.Screens.Play.HUD
 
             transform.StartTime = Time.Current;
             transform.EndTime = Time.Current + getProportionalDuration(currentValue, newValue);
-            transform.StartValue = currentValue;
             transform.EndValue = newValue;
             transform.Easing = RollingEasing;
 
@@ -207,7 +206,7 @@ namespace osu.Game.Screens.Play.HUD
 
         protected class TransformComboRoll : Transform<int, Drawable>
         {
-            public override int CurrentValue
+            public virtual int CurrentValue
             {
                 get
                 {
@@ -219,11 +218,8 @@ namespace osu.Game.Screens.Play.HUD
                 }
             }
 
-            public override void Apply(Drawable d)
+            public override void Apply(Drawable d) => ((ComboCounter)d).DisplayedCount = CurrentValue;
-            {
+            public override void ReadIntoStartValue(Drawable d) => StartValue = ((ComboCounter)d).DisplayedCount;
-                base.Apply(d);
-                ((ComboCounter)d).DisplayedCount = CurrentValue;
-            }
         }
 
         protected abstract void OnDisplayedCountRolling(int currentValue, int newValue);

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

@@ -36,7 +36,7 @@ namespace osu.Game.Screens.Play.HUD
 
         protected class TransformComboResult : Transform<ulong, Drawable>
         {
-            public override ulong CurrentValue
+            public virtual ulong CurrentValue
             {
                 get
                 {
@@ -48,11 +48,8 @@ namespace osu.Game.Screens.Play.HUD
                 }
             }
 
-            public override void Apply(Drawable d)
+            public override void Apply(Drawable d) => ((ComboResultCounter)d).DisplayedCount = CurrentValue;
-            {
+            public override void ReadIntoStartValue(Drawable d) => StartValue = ((ComboResultCounter)d).DisplayedCount;
-                base.Apply(d);
-                ((ComboResultCounter)d).DisplayedCount = CurrentValue;
-            }
         }
     }
 }

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

@@ -31,7 +31,7 @@ namespace osu.Game.Screens.Play.HUD
         {
             Children = new Drawable[]
             {
-                iconsContainer = new ReverseDepthFillFlowContainer<ModIcon>
+                iconsContainer = new ReverseChildIDFillFlowContainer<ModIcon>
                 {
                     Anchor = Anchor.TopCentre,
                     Origin = Anchor.TopCentre,

osu.Game/Screens/Play/KeyCounter.cs

@@ -20,15 +20,15 @@ namespace osu.Game.Screens.Play
         private SpriteText countSpriteText;
 
         public bool IsCounting { get; set; }
-        private int count;
+        private int countPresses;
-        public int Count
+        public int CountPresses
         {
-            get { return count; }
+            get { return countPresses; }
             private set
             {
-                if (count != value)
+                if (countPresses != value)
                 {
-                    count = value;
+                    countPresses = value;
                     countSpriteText.Text = value.ToString(@"#,0");
                 }
             }
@@ -45,7 +45,7 @@ namespace osu.Game.Screens.Play
                     isLit = value;
                     updateGlowSprite(value);
                     if (value && IsCounting)
-                        Count++;
+                        CountPresses++;
                 }
             }
         }
@@ -98,7 +98,7 @@ namespace osu.Game.Screens.Play
                         },
                         countSpriteText = new OsuSpriteText
                         {
-                            Text = Count.ToString(@"#,0"),
+                            Text = CountPresses.ToString(@"#,0"),
                             Anchor = Anchor.Centre,
                             Origin = Anchor.Centre,
                             RelativePositionAxes = Axes.Both,
@@ -128,6 +128,6 @@ namespace osu.Game.Screens.Play
             }
         }
 
-        public void ResetCount() => Count = 0;
+        public void ResetCount() => CountPresses = 0;
     }
 }

osu.Game/Screens/Play/Player.cs

@@ -200,7 +200,7 @@ namespace osu.Game.Screens.Play
 
             scoreProcessor = HitRenderer.CreateScoreProcessor();
 
-            hudOverlay.KeyCounter.Add(rulesetInstance.CreateGameplayKeys());
+            hudOverlay.KeyCounter.AddRange(rulesetInstance.CreateGameplayKeys());
             hudOverlay.BindProcessor(scoreProcessor);
             hudOverlay.BindHitRenderer(HitRenderer);
 

osu.Game/Screens/Play/PlayerLoader.cs

@@ -227,6 +227,7 @@ namespace osu.Game.Screens.Play
                                 {
                                     new Sprite
                                     {
+                                        RelativeSizeAxes = Axes.Both,
                                         Texture = beatmap?.Background,
                                         Origin = Anchor.Centre,
                                         Anchor = Anchor.Centre,

osu.Game/Screens/Ranking/Results.cs

@@ -163,6 +163,7 @@ namespace osu.Game.Screens.Ranking
                                     {
                                         new Sprite
                                         {
+                                            RelativeSizeAxes = Axes.Both,
                                             Alpha = 0.2f,
                                             Texture = Beatmap?.Background,
                                             Anchor = Anchor.Centre,

osu.Game/Screens/Ranking/ResultsPage.cs

@@ -40,7 +40,7 @@ namespace osu.Game.Screens.Ranking
         [BackgroundDependencyLoader]
         private void load(OsuColour colours)
         {
-            AddInternal(new Drawable[]
+            AddRangeInternal(new Drawable[]
             {
                 fill = new Box
                 {

osu.Game/Screens/Ranking/ResultsPageScore.cs

@@ -343,6 +343,7 @@ namespace osu.Game.Screens.Ranking
                 {
                     cover = new Sprite
                     {
+                        RelativeSizeAxes = Axes.Both,
                         FillMode = FillMode.Fill,
                         Anchor = Anchor.Centre,
                         Origin = Anchor.Centre,

osu.Game/Screens/Select/BeatmapCarousel.cs

@@ -12,7 +12,6 @@ using osu.Game.Beatmaps.Drawables;
 using osu.Game.Configuration;
 using osu.Framework.Input;
 using OpenTK.Input;
-using System.Collections;
 using osu.Framework.MathUtils;
 using System.Diagnostics;
 using System.Threading.Tasks;
@@ -22,7 +21,7 @@ using osu.Framework.Configuration;
 
 namespace osu.Game.Screens.Select
 {
-    internal class BeatmapCarousel : ScrollContainer, IEnumerable<BeatmapGroup>
+    internal class BeatmapCarousel : ScrollContainer
     {
         public BeatmapInfo SelectedBeatmap => selectedPanel?.Beatmap;
 
@@ -265,10 +264,6 @@ namespace osu.Game.Screens.Select
                 perform();
         }
 
-        public IEnumerator<BeatmapGroup> GetEnumerator() => groups.GetEnumerator();
-
-        IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();
-
         private BeatmapGroup createGroup(BeatmapSetInfo beatmapSet)
         {
             foreach (var b in beatmapSet.Beatmaps)
@@ -307,7 +302,7 @@ namespace osu.Game.Screens.Select
                 panels.Remove(p);
 
             scrollableContent.Remove(group.Header);
-            scrollableContent.Remove(group.BeatmapPanels);
+            scrollableContent.RemoveRange(group.BeatmapPanels);
 
             if (selectedGroup == group)
                 SelectNext();

osu.Game/Screens/Select/BeatmapDetailArea.cs

@@ -33,7 +33,7 @@ namespace osu.Game.Screens.Select
 
         public BeatmapDetailArea()
         {
-            AddInternal(new Drawable[]
+            AddRangeInternal(new Drawable[]
             {
                 new BeatmapDetailAreaTabControl
                 {
@@ -61,7 +61,7 @@ namespace osu.Game.Screens.Select
                 },
             });
 
-            Add(new Drawable[]
+            AddRange(new Drawable[]
             {
                 Details = new BeatmapDetails
                 {

osu.Game/Screens/Select/BeatmapInfoWedge.cs

@@ -152,6 +152,7 @@ namespace osu.Game.Screens.Select
                             // Zoomed-in and cropped beatmap background
                             new BeatmapBackgroundSprite(beatmap)
                             {
+                                RelativeSizeAxes = Axes.Both,
                                 Anchor = Anchor.Centre,
                                 Origin = Anchor.Centre,
                                 FillMode = FillMode.Fill,

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

@@ -31,6 +31,7 @@ namespace osu.Game.Screens.Select.Leaderboards
             {
                 rankSprite = new Sprite
                 {
+                    RelativeSizeAxes = Axes.Both,
                     Anchor = Anchor.Centre,
                     Origin = Anchor.Centre,
                     FillMode = FillMode.Fit

osu.Game/Screens/Select/Options/BeatmapOptionsOverlay.cs

@@ -70,7 +70,7 @@ namespace osu.Game.Screens.Select.Options
                     Scale = new Vector2(1, 0),
                     Colour = Color4.Black.Opacity(0.5f),
                 },
-                buttonsContainer = new ReverseDepthFillFlowContainer<BeatmapOptionsButton>
+                buttonsContainer = new ReverseChildIDFillFlowContainer<BeatmapOptionsButton>
                 {
                     Height = height,
                     RelativePositionAxes = Axes.X,

osu.Game/Screens/Tournament/Drawings.cs

@@ -82,6 +82,7 @@ namespace osu.Game.Screens.Tournament
                 },
                 new Sprite
                 {
+                    RelativeSizeAxes = Axes.Both,
                     FillMode = FillMode.Fill,
                     Texture = textures.Get(@"Backgrounds/Drawings/background.png")
                 },

osu.Game/Screens/Tournament/Group.cs

@@ -151,9 +151,9 @@ namespace osu.Game.Screens.Tournament
                         {
                             flagSprite = new Sprite
                             {
+                                RelativeSizeAxes = Axes.Both,
                                 Anchor = Anchor.TopCentre,
                                 Origin = Anchor.TopCentre,
-
                                 FillMode = FillMode.Fit
                             },
                             new OsuSpriteText

osu.Game/Screens/Tournament/ScrollingTeamContainer.cs

@@ -297,7 +297,7 @@ namespace osu.Game.Screens.Tournament
             }
         }
 
-        private void speedTo(float value, double duration = 0, EasingTypes easing = EasingTypes.None) => TransformTo(() => speed, value, duration, easing, new TransformScrollSpeed());
+        private void speedTo(float value, double duration = 0, EasingTypes easing = EasingTypes.None) => TransformTo(value, duration, easing, new TransformScrollSpeed());
 
         private enum ScrollState
         {
@@ -310,11 +310,8 @@ namespace osu.Game.Screens.Tournament
 
         public class TransformScrollSpeed : TransformFloat<Drawable>
         {
-            public override void Apply(Drawable d)
+            public override void Apply(Drawable d) => ((ScrollingTeamContainer)d).speed = CurrentValue;
-            {
+            public override void ReadIntoStartValue(Drawable d) => StartValue = ((ScrollingTeamContainer)d).speed;
-                base.Apply(d);
-                ((ScrollingTeamContainer)d).speed = CurrentValue;
-            }
         }
 
         public class ScrollingTeam : Container

osu.Game/Users/Avatar.cs

@@ -31,6 +31,7 @@ namespace osu.Game.Users
 
             Add(new Sprite
             {
+                RelativeSizeAxes = Axes.Both,
                 Texture = texture,
                 FillMode = FillMode.Fit,
                 Anchor = Anchor.Centre,

osu.Game/Users/UserPanel.cs

@@ -46,6 +46,7 @@ namespace osu.Game.Users
             {
                 new AsyncLoadWrapper(new CoverBackgroundSprite(user)
                 {
+                    RelativeSizeAxes = Axes.Both,
                     Anchor = Anchor.Centre,
                     Origin = Anchor.Centre,
                     FillMode = FillMode.Fill,

osu.Game/osu.Game.csproj

@@ -190,7 +190,6 @@
     <Compile Include="Rulesets\Objects\Drawables\IScrollingHitObject.cs" />
     <Compile Include="Rulesets\Judgements\Judgement.cs" />
     <Compile Include="Rulesets\Objects\HitObjectParser.cs" />
-    <Compile Include="Rulesets\Objects\HitObjectStartTimeComparer.cs" />
     <Compile Include="Rulesets\Objects\Types\IHasCombo.cs" />
     <Compile Include="Rulesets\Objects\Types\IHasEndTime.cs" />
     <Compile Include="Rulesets\Objects\Types\IHasDistance.cs" />
@@ -476,7 +475,7 @@
     <Compile Include="Overlays\Direct\DirectListPanel.cs" />
     <Compile Include="Database\OnlineWorkingBeatmap.cs" />
     <Compile Include="Database\BeatmapOnlineInfo.cs" />
-    <Compile Include="Graphics\Containers\ReverseDepthFillFlowContainer.cs" />
+    <Compile Include="Graphics\Containers\ReverseChildIDFillFlowContainer.cs" />
     <Compile Include="Database\RankStatus.cs" />
     <Compile Include="Overlays\SearchableList\SearchableListHeader.cs" />
     <Compile Include="Overlays\SearchableList\HeaderTabControl.cs" />