From 592e05a2c8f44ceb66eb4d5458b824f0513a079b Mon Sep 17 00:00:00 2001
From: smoogipooo <smoogipooo@gmail.com>
Date: Sun, 12 Mar 2017 00:34:21 +0900
Subject: [PATCH 1/7] Better beatmap conversion model.

---
 .../Beatmaps/CatchBeatmapConverter.cs         | 21 ++++++
 .../CatchDifficultyCalculator.cs              |  3 -
 osu.Game.Modes.Catch/CatchRuleset.cs          |  6 ++
 osu.Game.Modes.Catch/UI/CatchHitRenderer.cs   |  3 -
 .../osu.Game.Modes.Catch.csproj               |  1 +
 .../Beatmaps/ManiaBeatmapConverter.cs         | 21 ++++++
 .../ManiaDifficultyCalculator.cs              |  3 -
 osu.Game.Modes.Mania/ManiaRuleset.cs          |  6 ++
 osu.Game.Modes.Mania/UI/ManiaHitRenderer.cs   |  3 -
 .../osu.Game.Modes.Mania.csproj               |  2 +
 .../OsuBeatmapConverter.cs}                   | 39 +++++++----
 osu.Game.Modes.Osu/OsuDifficultyCalculator.cs |  3 -
 osu.Game.Modes.Osu/OsuRuleset.cs              |  6 ++
 osu.Game.Modes.Osu/UI/OsuHitRenderer.cs       |  3 -
 osu.Game.Modes.Osu/osu.Game.Modes.Osu.csproj  |  2 +-
 .../Beatmaps/TaikoBeatmapConverter.cs         | 20 ++++++
 .../TaikoDifficultyCalculator.cs              |  3 -
 osu.Game.Modes.Taiko/TaikoRuleset.cs          |  6 ++
 osu.Game.Modes.Taiko/UI/TaikoHitRenderer.cs   |  3 -
 .../osu.Game.Modes.Taiko.csproj               |  1 +
 osu.Game/Beatmaps/Beatmap.cs                  | 68 ++++++++++++++++---
 osu.Game/Beatmaps/DifficultyCalculator.cs     |  4 +-
 osu.Game/Beatmaps/IBeatmapCoverter.cs         | 12 ++++
 osu.Game/Modes/Ruleset.cs                     |  2 +
 osu.Game/Modes/UI/HitRenderer.cs              | 20 ++----
 osu.Game/osu.Game.csproj                      |  1 +
 26 files changed, 196 insertions(+), 66 deletions(-)
 create mode 100644 osu.Game.Modes.Catch/Beatmaps/CatchBeatmapConverter.cs
 create mode 100644 osu.Game.Modes.Mania/Beatmaps/ManiaBeatmapConverter.cs
 rename osu.Game.Modes.Osu/{Objects/OsuHitObjectConverter.cs => Beatmaps/OsuBeatmapConverter.cs} (87%)
 create mode 100644 osu.Game.Modes.Taiko/Beatmaps/TaikoBeatmapConverter.cs
 create mode 100644 osu.Game/Beatmaps/IBeatmapCoverter.cs

diff --git a/osu.Game.Modes.Catch/Beatmaps/CatchBeatmapConverter.cs b/osu.Game.Modes.Catch/Beatmaps/CatchBeatmapConverter.cs
new file mode 100644
index 0000000000..6460751570
--- /dev/null
+++ b/osu.Game.Modes.Catch/Beatmaps/CatchBeatmapConverter.cs
@@ -0,0 +1,21 @@
+// 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.Game.Beatmaps;
+using osu.Game.Modes.Catch.Objects;
+using System.Collections.Generic;
+
+namespace osu.Game.Modes.Catch.Beatmaps
+{
+    internal class CatchBeatmapConverter : IBeatmapConverter<CatchBaseHit>
+    {
+        public Beatmap<CatchBaseHit> Convert(Beatmap original)
+        {
+            return new Beatmap<CatchBaseHit>(original)
+            {
+                HitObjects = new List<CatchBaseHit>() // Todo: Convert HitObjects
+            };
+        }
+    }
+}
diff --git a/osu.Game.Modes.Catch/CatchDifficultyCalculator.cs b/osu.Game.Modes.Catch/CatchDifficultyCalculator.cs
index ccc4097d59..01fa1a00d4 100644
--- a/osu.Game.Modes.Catch/CatchDifficultyCalculator.cs
+++ b/osu.Game.Modes.Catch/CatchDifficultyCalculator.cs
@@ -3,7 +3,6 @@
 
 using osu.Game.Beatmaps;
 using osu.Game.Modes.Catch.Objects;
-using osu.Game.Modes.Objects;
 using System;
 using System.Collections.Generic;
 
@@ -17,8 +16,6 @@ namespace osu.Game.Modes.Catch
         {
         }
 
-        protected override HitObjectConverter<CatchBaseHit> Converter => new CatchConverter();
-
         protected override double CalculateInternal(Dictionary<String, String> categoryDifficulty)
         {
             return 0;
diff --git a/osu.Game.Modes.Catch/CatchRuleset.cs b/osu.Game.Modes.Catch/CatchRuleset.cs
index 08edeb7bcb..2cdd35cf3a 100644
--- a/osu.Game.Modes.Catch/CatchRuleset.cs
+++ b/osu.Game.Modes.Catch/CatchRuleset.cs
@@ -4,6 +4,7 @@
 using OpenTK.Input;
 using osu.Game.Beatmaps;
 using osu.Game.Graphics;
+using osu.Game.Modes.Catch.Beatmaps;
 using osu.Game.Modes.Catch.UI;
 using osu.Game.Modes.Objects;
 using osu.Game.Modes.UI;
@@ -91,5 +92,10 @@ namespace osu.Game.Modes.Catch
         public override HitObjectParser CreateHitObjectParser() => new NullHitObjectParser();
 
         public override DifficultyCalculator CreateDifficultyCalculator(Beatmap beatmap) => new CatchDifficultyCalculator(beatmap);
+
+        public override IBeatmapConverter<CatchBaseHit> CreateBeatmapConverter<CatchBaseHit>()
+        {
+            return (IBeatmapConverter<CatchBaseHit>)new CatchBeatmapConverter();
+        }
     }
 }
diff --git a/osu.Game.Modes.Catch/UI/CatchHitRenderer.cs b/osu.Game.Modes.Catch/UI/CatchHitRenderer.cs
index ed0c8b4747..703eb6fe91 100644
--- a/osu.Game.Modes.Catch/UI/CatchHitRenderer.cs
+++ b/osu.Game.Modes.Catch/UI/CatchHitRenderer.cs
@@ -3,7 +3,6 @@
 
 using osu.Game.Beatmaps;
 using osu.Game.Modes.Catch.Objects;
-using osu.Game.Modes.Objects;
 using osu.Game.Modes.Objects.Drawables;
 using osu.Game.Modes.UI;
 
@@ -16,8 +15,6 @@ namespace osu.Game.Modes.Catch.UI
         {
         }
 
-        protected override HitObjectConverter<CatchBaseHit> Converter => new CatchConverter();
-
         protected override Playfield<CatchBaseHit> CreatePlayfield() => new CatchPlayfield();
 
         protected override DrawableHitObject<CatchBaseHit> GetVisualRepresentation(CatchBaseHit h) => null;// new DrawableFruit(h);
diff --git a/osu.Game.Modes.Catch/osu.Game.Modes.Catch.csproj b/osu.Game.Modes.Catch/osu.Game.Modes.Catch.csproj
index 663d12bb4d..10abb312fc 100644
--- a/osu.Game.Modes.Catch/osu.Game.Modes.Catch.csproj
+++ b/osu.Game.Modes.Catch/osu.Game.Modes.Catch.csproj
@@ -47,6 +47,7 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="Beatmaps\CatchBeatmapConverter.cs" />
     <Compile Include="CatchDifficultyCalculator.cs" />
     <Compile Include="Objects\CatchBaseHit.cs" />
     <Compile Include="Objects\CatchConverter.cs" />
diff --git a/osu.Game.Modes.Mania/Beatmaps/ManiaBeatmapConverter.cs b/osu.Game.Modes.Mania/Beatmaps/ManiaBeatmapConverter.cs
new file mode 100644
index 0000000000..0f42da4ac8
--- /dev/null
+++ b/osu.Game.Modes.Mania/Beatmaps/ManiaBeatmapConverter.cs
@@ -0,0 +1,21 @@
+// 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.Game.Beatmaps;
+using osu.Game.Modes.Mania.Objects;
+using System.Collections.Generic;
+
+namespace osu.Game.Modes.Mania.Beatmaps
+{
+    internal class ManiaBeatmapConverter : IBeatmapConverter<ManiaBaseHit>
+    {
+        public Beatmap<ManiaBaseHit> Convert(Beatmap original)
+        {
+            return new Beatmap<ManiaBaseHit>(original)
+            {
+                HitObjects = new List<ManiaBaseHit>() // Todo: Implement
+            };
+        }
+    }
+}
diff --git a/osu.Game.Modes.Mania/ManiaDifficultyCalculator.cs b/osu.Game.Modes.Mania/ManiaDifficultyCalculator.cs
index 975b78c215..07c0749904 100644
--- a/osu.Game.Modes.Mania/ManiaDifficultyCalculator.cs
+++ b/osu.Game.Modes.Mania/ManiaDifficultyCalculator.cs
@@ -3,7 +3,6 @@
 
 using osu.Game.Beatmaps;
 using osu.Game.Modes.Mania.Objects;
-using osu.Game.Modes.Objects;
 using System;
 using System.Collections.Generic;
 
@@ -20,8 +19,6 @@ namespace osu.Game.Modes.Mania
             this.columns = columns;
         }
 
-        protected override HitObjectConverter<ManiaBaseHit> Converter => new ManiaConverter(columns);
-
         protected override double CalculateInternal(Dictionary<String, String> categoryDifficulty)
         {
             return 0;
diff --git a/osu.Game.Modes.Mania/ManiaRuleset.cs b/osu.Game.Modes.Mania/ManiaRuleset.cs
index e6e9cfd799..7d88942798 100644
--- a/osu.Game.Modes.Mania/ManiaRuleset.cs
+++ b/osu.Game.Modes.Mania/ManiaRuleset.cs
@@ -3,6 +3,7 @@
 
 using osu.Game.Beatmaps;
 using osu.Game.Graphics;
+using osu.Game.Modes.Mania.Beatmaps;
 using osu.Game.Modes.Mania.UI;
 using osu.Game.Modes.Objects;
 using osu.Game.Modes.UI;
@@ -106,5 +107,10 @@ namespace osu.Game.Modes.Mania
         public override HitObjectParser CreateHitObjectParser() => new NullHitObjectParser();
 
         public override DifficultyCalculator CreateDifficultyCalculator(Beatmap beatmap) => new ManiaDifficultyCalculator(beatmap);
+
+        public override IBeatmapConverter<ManiaBaseHit> CreateBeatmapConverter<ManiaBaseHit>()
+        {
+            return (IBeatmapConverter<ManiaBaseHit>)new ManiaBeatmapConverter();
+        }
     }
 }
diff --git a/osu.Game.Modes.Mania/UI/ManiaHitRenderer.cs b/osu.Game.Modes.Mania/UI/ManiaHitRenderer.cs
index 82dd2f2eeb..33b82738f8 100644
--- a/osu.Game.Modes.Mania/UI/ManiaHitRenderer.cs
+++ b/osu.Game.Modes.Mania/UI/ManiaHitRenderer.cs
@@ -3,7 +3,6 @@
 
 using osu.Game.Beatmaps;
 using osu.Game.Modes.Mania.Objects;
-using osu.Game.Modes.Objects;
 using osu.Game.Modes.Objects.Drawables;
 using osu.Game.Modes.UI;
 
@@ -19,8 +18,6 @@ namespace osu.Game.Modes.Mania.UI
             this.columns = columns;
         }
 
-        protected override HitObjectConverter<ManiaBaseHit> Converter => new ManiaConverter(columns);
-
         protected override Playfield<ManiaBaseHit> CreatePlayfield() => new ManiaPlayfield(columns);
 
         protected override DrawableHitObject<ManiaBaseHit> GetVisualRepresentation(ManiaBaseHit h)
diff --git a/osu.Game.Modes.Mania/osu.Game.Modes.Mania.csproj b/osu.Game.Modes.Mania/osu.Game.Modes.Mania.csproj
index 354f0b8541..66e46f9e48 100644
--- a/osu.Game.Modes.Mania/osu.Game.Modes.Mania.csproj
+++ b/osu.Game.Modes.Mania/osu.Game.Modes.Mania.csproj
@@ -47,6 +47,7 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="Beatmaps\ManiaBeatmapConverter.cs" />
     <Compile Include="ManiaDifficultyCalculator.cs" />
     <Compile Include="Objects\Drawable\DrawableNote.cs" />
     <Compile Include="Objects\HoldNote.cs" />
@@ -85,6 +86,7 @@
     <None Include="OpenTK.dll.config" />
     <None Include="packages.config" />
   </ItemGroup>
+  <ItemGroup />
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
        Other similar extension points exist, see Microsoft.Common.targets.
diff --git a/osu.Game.Modes.Osu/Objects/OsuHitObjectConverter.cs b/osu.Game.Modes.Osu/Beatmaps/OsuBeatmapConverter.cs
similarity index 87%
rename from osu.Game.Modes.Osu/Objects/OsuHitObjectConverter.cs
rename to osu.Game.Modes.Osu/Beatmaps/OsuBeatmapConverter.cs
index adac253cc3..33d4562032 100644
--- a/osu.Game.Modes.Osu/Objects/OsuHitObjectConverter.cs
+++ b/osu.Game.Modes.Osu/Beatmaps/OsuBeatmapConverter.cs
@@ -1,35 +1,45 @@
 // 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 osu.Game.Modes.Objects;
-using osu.Game.Beatmaps;
-using osu.Game.Modes.Osu.Objects.Drawables;
-using OpenTK;
 
-namespace osu.Game.Modes.Osu.Objects
+using OpenTK;
+using osu.Game.Beatmaps;
+using osu.Game.Modes.Objects;
+using osu.Game.Modes.Osu.Objects;
+using osu.Game.Modes.Osu.Objects.Drawables;
+using System.Collections.Generic;
+
+namespace osu.Game.Modes.Osu.Beatmaps
 {
-    public class OsuHitObjectConverter : HitObjectConverter<OsuHitObject>
+    internal class OsuBeatmapConverter : IBeatmapConverter<OsuHitObject>
     {
-        public override List<OsuHitObject> Convert(Beatmap beatmap)
+        public Beatmap<OsuHitObject> Convert(Beatmap original)
         {
-            List<OsuHitObject> output = new List<OsuHitObject>();
+            return new Beatmap<OsuHitObject>(original)
+            {
+                HitObjects = convertHitObject(original.HitObjects, original.BeatmapInfo?.StackLeniency ?? 0.7f)
+            };
+        }
+
+        private List<OsuHitObject> convertHitObject(List<HitObject> hitObjects, float stackLeniency)
+        {
+            List<OsuHitObject> converted = new List<OsuHitObject>();
 
             int combo = 0;
-            foreach (HitObject h in beatmap.HitObjects)
+            foreach (HitObject h in hitObjects)
             {
                 if (h.NewCombo) combo = 0;
 
                 h.ComboIndex = combo++;
-                output.Add(h as OsuHitObject);
+                converted.Add(h as OsuHitObject);
             }
 
-            UpdateStacking(output, beatmap.BeatmapInfo?.StackLeniency ?? 0.7f);
+            updateStacking(converted, stackLeniency);
 
-            return output;
+            return converted;
         }
 
-        public static void UpdateStacking(List<OsuHitObject> hitObjects, float stackLeniency, int startIndex = 0, int endIndex = -1)
+        private void updateStacking(List<OsuHitObject> hitObjects, float stackLeniency, int startIndex = 0, int endIndex = -1)
         {
             if (endIndex == -1)
                 endIndex = hitObjects.Count - 1;
@@ -171,6 +181,5 @@ namespace osu.Game.Modes.Osu.Objects
                 }
             }
         }
-
     }
 }
diff --git a/osu.Game.Modes.Osu/OsuDifficultyCalculator.cs b/osu.Game.Modes.Osu/OsuDifficultyCalculator.cs
index a42fe70cf3..86c6596138 100644
--- a/osu.Game.Modes.Osu/OsuDifficultyCalculator.cs
+++ b/osu.Game.Modes.Osu/OsuDifficultyCalculator.cs
@@ -5,7 +5,6 @@ using osu.Game.Beatmaps;
 using osu.Game.Modes.Osu.Objects;
 using System;
 using System.Collections.Generic;
-using osu.Game.Modes.Objects;
 
 namespace osu.Game.Modes.Osu
 {
@@ -25,8 +24,6 @@ namespace osu.Game.Modes.Osu
         {
         }
 
-        protected override HitObjectConverter<OsuHitObject> Converter => new OsuHitObjectConverter();
-
         protected override void PreprocessHitObjects()
         {
             foreach (var h in Objects)
diff --git a/osu.Game.Modes.Osu/OsuRuleset.cs b/osu.Game.Modes.Osu/OsuRuleset.cs
index 0c46ece6da..33427e0f55 100644
--- a/osu.Game.Modes.Osu/OsuRuleset.cs
+++ b/osu.Game.Modes.Osu/OsuRuleset.cs
@@ -5,6 +5,7 @@ using OpenTK.Input;
 using osu.Game.Beatmaps;
 using osu.Game.Graphics;
 using osu.Game.Modes.Objects;
+using osu.Game.Modes.Osu.Beatmaps;
 using osu.Game.Modes.Osu.Objects;
 using osu.Game.Modes.Osu.UI;
 using osu.Game.Modes.UI;
@@ -118,5 +119,10 @@ namespace osu.Game.Modes.Osu
             new KeyCounterMouse(MouseButton.Left),
             new KeyCounterMouse(MouseButton.Right)
         };
+
+        public override IBeatmapConverter<OsuHitObject> CreateBeatmapConverter<OsuHitObject>()
+        {
+            return (IBeatmapConverter<OsuHitObject>)new OsuBeatmapConverter();
+        }
     }
 }
diff --git a/osu.Game.Modes.Osu/UI/OsuHitRenderer.cs b/osu.Game.Modes.Osu/UI/OsuHitRenderer.cs
index dab46aed8f..118f96e145 100644
--- a/osu.Game.Modes.Osu/UI/OsuHitRenderer.cs
+++ b/osu.Game.Modes.Osu/UI/OsuHitRenderer.cs
@@ -2,7 +2,6 @@
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
 using osu.Game.Beatmaps;
-using osu.Game.Modes.Objects;
 using osu.Game.Modes.Objects.Drawables;
 using osu.Game.Modes.Osu.Objects;
 using osu.Game.Modes.Osu.Objects.Drawables;
@@ -17,8 +16,6 @@ namespace osu.Game.Modes.Osu.UI
         {
         }
 
-        protected override HitObjectConverter<OsuHitObject> Converter => new OsuHitObjectConverter();
-
         protected override Playfield<OsuHitObject> CreatePlayfield() => new OsuPlayfield();
 
         protected override DrawableHitObject<OsuHitObject> GetVisualRepresentation(OsuHitObject h)
diff --git a/osu.Game.Modes.Osu/osu.Game.Modes.Osu.csproj b/osu.Game.Modes.Osu/osu.Game.Modes.Osu.csproj
index ea03841b82..c214c881d8 100644
--- a/osu.Game.Modes.Osu/osu.Game.Modes.Osu.csproj
+++ b/osu.Game.Modes.Osu/osu.Game.Modes.Osu.csproj
@@ -43,6 +43,7 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="Beatmaps\OsuBeatmapConverter.cs" />
     <Compile Include="Objects\BezierApproximator.cs" />
     <Compile Include="Objects\CircularArcApproximator.cs" />
     <Compile Include="Objects\Drawables\DrawableOsuHitObject.cs" />
@@ -80,7 +81,6 @@
     <Compile Include="Objects\HitCircle.cs" />
     <Compile Include="Objects\Drawables\DrawableHitCircle.cs" />
     <Compile Include="Objects\OsuHitObject.cs" />
-    <Compile Include="Objects\OsuHitObjectConverter.cs" />
     <Compile Include="Objects\Slider.cs" />
     <Compile Include="Objects\Spinner.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
diff --git a/osu.Game.Modes.Taiko/Beatmaps/TaikoBeatmapConverter.cs b/osu.Game.Modes.Taiko/Beatmaps/TaikoBeatmapConverter.cs
new file mode 100644
index 0000000000..3230010fda
--- /dev/null
+++ b/osu.Game.Modes.Taiko/Beatmaps/TaikoBeatmapConverter.cs
@@ -0,0 +1,20 @@
+// 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.Game.Beatmaps;
+using osu.Game.Modes.Taiko.Objects;
+using System.Collections.Generic;
+
+namespace osu.Game.Modes.Taiko.Beatmaps
+{
+    internal class TaikoBeatmapConverter : IBeatmapConverter<TaikoBaseHit>
+    {
+        public Beatmap<TaikoBaseHit> Convert(Beatmap original)
+        {
+            return new Beatmap<TaikoBaseHit>(original)
+            {
+                HitObjects = new List<TaikoBaseHit>() // Todo: Implement
+            };
+        }
+    }
+}
diff --git a/osu.Game.Modes.Taiko/TaikoDifficultyCalculator.cs b/osu.Game.Modes.Taiko/TaikoDifficultyCalculator.cs
index 5067cef2b3..a90e2f40fa 100644
--- a/osu.Game.Modes.Taiko/TaikoDifficultyCalculator.cs
+++ b/osu.Game.Modes.Taiko/TaikoDifficultyCalculator.cs
@@ -2,7 +2,6 @@
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
 using osu.Game.Beatmaps;
-using osu.Game.Modes.Objects;
 using osu.Game.Modes.Taiko.Objects;
 using System;
 using System.Collections.Generic;
@@ -17,8 +16,6 @@ namespace osu.Game.Modes.Taiko
         {
         }
 
-        protected override HitObjectConverter<TaikoBaseHit> Converter => new TaikoConverter();
-
         protected override double CalculateInternal(Dictionary<String, String> categoryDifficulty)
         {
             return 0;
diff --git a/osu.Game.Modes.Taiko/TaikoRuleset.cs b/osu.Game.Modes.Taiko/TaikoRuleset.cs
index 418519d90c..4bca82a70b 100644
--- a/osu.Game.Modes.Taiko/TaikoRuleset.cs
+++ b/osu.Game.Modes.Taiko/TaikoRuleset.cs
@@ -5,6 +5,7 @@ using OpenTK.Input;
 using osu.Game.Beatmaps;
 using osu.Game.Graphics;
 using osu.Game.Modes.Objects;
+using osu.Game.Modes.Taiko.Beatmaps;
 using osu.Game.Modes.Taiko.UI;
 using osu.Game.Modes.UI;
 using osu.Game.Screens.Play;
@@ -92,5 +93,10 @@ namespace osu.Game.Modes.Taiko
         public override HitObjectParser CreateHitObjectParser() => new NullHitObjectParser();
 
         public override DifficultyCalculator CreateDifficultyCalculator(Beatmap beatmap) => new TaikoDifficultyCalculator(beatmap);
+
+        public override IBeatmapConverter<TaikoBaseHit> CreateBeatmapConverter<TaikoBaseHit>()
+        {
+            return (IBeatmapConverter<TaikoBaseHit>)new TaikoBeatmapConverter();
+        }
     }
 }
diff --git a/osu.Game.Modes.Taiko/UI/TaikoHitRenderer.cs b/osu.Game.Modes.Taiko/UI/TaikoHitRenderer.cs
index e29e13823d..e7d0372f43 100644
--- a/osu.Game.Modes.Taiko/UI/TaikoHitRenderer.cs
+++ b/osu.Game.Modes.Taiko/UI/TaikoHitRenderer.cs
@@ -2,7 +2,6 @@
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
 using osu.Game.Beatmaps;
-using osu.Game.Modes.Objects;
 using osu.Game.Modes.Objects.Drawables;
 using osu.Game.Modes.Taiko.Objects;
 using osu.Game.Modes.UI;
@@ -16,8 +15,6 @@ namespace osu.Game.Modes.Taiko.UI
         {
         }
 
-        protected override HitObjectConverter<TaikoBaseHit> Converter => new TaikoConverter();
-
         protected override Playfield<TaikoBaseHit> CreatePlayfield() => new TaikoPlayfield();
 
         protected override DrawableHitObject<TaikoBaseHit> GetVisualRepresentation(TaikoBaseHit h) => null;// new DrawableTaikoHit(h);
diff --git a/osu.Game.Modes.Taiko/osu.Game.Modes.Taiko.csproj b/osu.Game.Modes.Taiko/osu.Game.Modes.Taiko.csproj
index 35f5a2d686..0089e84532 100644
--- a/osu.Game.Modes.Taiko/osu.Game.Modes.Taiko.csproj
+++ b/osu.Game.Modes.Taiko/osu.Game.Modes.Taiko.csproj
@@ -47,6 +47,7 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="Beatmaps\TaikoBeatmapConverter.cs" />
     <Compile Include="TaikoDifficultyCalculator.cs" />
     <Compile Include="Objects\Drawable\DrawableTaikoHit.cs" />
     <Compile Include="Objects\TaikoBaseHit.cs" />
diff --git a/osu.Game/Beatmaps/Beatmap.cs b/osu.Game/Beatmaps/Beatmap.cs
index f195f8f2ba..39b9fd13b8 100644
--- a/osu.Game/Beatmaps/Beatmap.cs
+++ b/osu.Game/Beatmaps/Beatmap.cs
@@ -1,23 +1,62 @@
 // 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 OpenTK.Graphics;
 using osu.Game.Beatmaps.Timing;
 using osu.Game.Database;
-using osu.Game.Modes.Objects;
 using osu.Game.Modes;
+using osu.Game.Modes.Objects;
+using System.Collections.Generic;
+using System.Linq;
 
 namespace osu.Game.Beatmaps
 {
-    public class Beatmap
+    public class BeatmapBase
     {
-        public BeatmapInfo BeatmapInfo { get; set; }
+        private BeatmapBase original;
+
+        public BeatmapBase(BeatmapBase original = null)
+        {
+            this.original = original;
+        }
+
+        private BeatmapInfo beatmapInfo;
+        public BeatmapInfo BeatmapInfo
+        {
+            get { return beatmapInfo ?? original?.BeatmapInfo; }
+            set { beatmapInfo = value; }
+        }
+
+        private List<ControlPoint> controlPoints;
+        public List<ControlPoint> ControlPoints
+        {
+            get { return controlPoints ?? original?.ControlPoints; }
+            set { controlPoints = value; }
+        }
+
+        private List<Color4> comboColors;
+        public List<Color4> ComboColors
+        {
+            get { return comboColors ?? original?.ComboColors; }
+            set { comboColors = value; }
+        }
+
         public BeatmapMetadata Metadata => BeatmapInfo?.Metadata ?? BeatmapInfo?.BeatmapSet?.Metadata;
-        public List<HitObject> HitObjects { get; set; }
-        public List<ControlPoint> ControlPoints { get; set; }
-        public List<Color4> ComboColors { get; set; }
+    }
+
+    /// <summary>
+    /// A generic beatmap that does not contain HitObjects.
+    /// </summary>
+    public class Beatmap<T> : BeatmapBase
+        where T : HitObject
+    {
+        public List<T> HitObjects;
+
+        public Beatmap(BeatmapBase original = null)
+            : base(original)
+        {
+        }
+
         public double BPMMaximum => 60000 / (ControlPoints?.Where(c => c.BeatLength != 0).OrderBy(c => c.BeatLength).FirstOrDefault() ?? ControlPoint.Default).BeatLength;
         public double BPMMinimum => 60000 / (ControlPoints?.Where(c => c.BeatLength != 0).OrderByDescending(c => c.BeatLength).FirstOrDefault() ?? ControlPoint.Default).BeatLength;
         public double BPMMode => BPMAt(ControlPoints.Where(c => c.BeatLength != 0).GroupBy(c => c.BeatLength).OrderByDescending(grp => grp.Count()).First().First().Time);
@@ -58,7 +97,20 @@ namespace osu.Game.Beatmaps
 
             return timingPoint ?? ControlPoint.Default;
         }
+    }
+
+    public class Beatmap : Beatmap<HitObject>
+    {
+        public Beatmap(BeatmapBase original = null)
+            : base(original)
+        {
+        }
 
         public double CalculateStarDifficulty() => Ruleset.GetRuleset(BeatmapInfo.Mode).CreateDifficultyCalculator(this).Calculate();
+
+        public Beatmap<T> ConvertTo<T>() where T : HitObject
+        {
+            return Ruleset.GetRuleset(BeatmapInfo.Mode).CreateBeatmapConverter<T>().Convert(this);
+        }
     }
 }
diff --git a/osu.Game/Beatmaps/DifficultyCalculator.cs b/osu.Game/Beatmaps/DifficultyCalculator.cs
index cb9d9f6cbc..cb021b7490 100644
--- a/osu.Game/Beatmaps/DifficultyCalculator.cs
+++ b/osu.Game/Beatmaps/DifficultyCalculator.cs
@@ -35,11 +35,9 @@ namespace osu.Game.Beatmaps
     {
         protected List<T> Objects;
 
-        protected abstract HitObjectConverter<T> Converter { get; }
-
         protected DifficultyCalculator(Beatmap beatmap)
         {
-            Objects = Converter.Convert(beatmap);
+            Objects = beatmap.ConvertTo<T>().HitObjects;
             PreprocessHitObjects();
         }
 
diff --git a/osu.Game/Beatmaps/IBeatmapCoverter.cs b/osu.Game/Beatmaps/IBeatmapCoverter.cs
new file mode 100644
index 0000000000..da5892c168
--- /dev/null
+++ b/osu.Game/Beatmaps/IBeatmapCoverter.cs
@@ -0,0 +1,12 @@
+// 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.Game.Modes.Objects;
+
+namespace osu.Game.Beatmaps
+{
+    public interface IBeatmapConverter<T> where T : HitObject
+    {
+        Beatmap<T> Convert(Beatmap original);
+    }
+}
diff --git a/osu.Game/Modes/Ruleset.cs b/osu.Game/Modes/Ruleset.cs
index d8892e64e9..54137b2402 100644
--- a/osu.Game/Modes/Ruleset.cs
+++ b/osu.Game/Modes/Ruleset.cs
@@ -37,6 +37,8 @@ namespace osu.Game.Modes
 
         public abstract DifficultyCalculator CreateDifficultyCalculator(Beatmap beatmap);
 
+        public abstract IBeatmapConverter<T> CreateBeatmapConverter<T>() where T : HitObject;
+
         public static void Register(Ruleset ruleset) => availableRulesets.TryAdd(ruleset.PlayMode, ruleset.GetType());
 
         protected abstract PlayMode PlayMode { get; }
diff --git a/osu.Game/Modes/UI/HitRenderer.cs b/osu.Game/Modes/UI/HitRenderer.cs
index 360551c89f..3db02a2021 100644
--- a/osu.Game/Modes/UI/HitRenderer.cs
+++ b/osu.Game/Modes/UI/HitRenderer.cs
@@ -32,19 +32,9 @@ namespace osu.Game.Modes.UI
         /// </summary>
         protected abstract int JudgementCount { get; }
 
-        /// <summary>
-        /// The beatmap this HitRenderer is initialized with.
-        /// </summary>
-        protected readonly Beatmap Beatmap;
-
         private int maxJudgements;
         private int countJudgements;
 
-        protected HitRenderer(Beatmap beatmap)
-        {
-            Beatmap = beatmap;
-        }
-
         protected override void LoadComplete()
         {
             base.LoadComplete();
@@ -69,9 +59,6 @@ namespace osu.Game.Modes.UI
         public override Func<Vector2, Vector2> MapPlayfieldToScreenSpace => Playfield.ScaledContent.ToScreenSpace;
         public IEnumerable<DrawableHitObject> DrawableObjects => Playfield.HitObjects.Children;
 
-        protected abstract HitObjectConverter<TObject> Converter { get; }
-        protected virtual List<TObject> Convert(Beatmap beatmap) => Converter.Convert(beatmap);
-
         protected override Container<Drawable> Content => content;
 
         private int judgementCount;
@@ -79,11 +66,14 @@ namespace osu.Game.Modes.UI
 
         protected Playfield<TObject> Playfield;
 
+        protected Beatmap<TObject> Beatmap;
+
         private Container content;
 
         protected HitRenderer(Beatmap beatmap)
-            : base(beatmap)
         {
+            Beatmap = beatmap.ConvertTo<TObject>();
+
             RelativeSizeAxes = Axes.Both;
 
             InputManager.Add(content = new Container
@@ -107,7 +97,7 @@ namespace osu.Game.Modes.UI
 
         private void loadObjects()
         {
-            foreach (TObject h in Convert(Beatmap))
+            foreach (TObject h in Beatmap.HitObjects)
             {
                 DrawableHitObject<TObject> drawableObject = GetVisualRepresentation(h);
 
diff --git a/osu.Game/osu.Game.csproj b/osu.Game/osu.Game.csproj
index 81bc844872..3d4a763cb8 100644
--- a/osu.Game/osu.Game.csproj
+++ b/osu.Game/osu.Game.csproj
@@ -73,6 +73,7 @@
   <ItemGroup>
     <Compile Include="Beatmaps\Drawables\BeatmapBackgroundSprite.cs" />
     <Compile Include="Beatmaps\DifficultyCalculator.cs" />
+    <Compile Include="Beatmaps\IBeatmapCoverter.cs" />
     <Compile Include="Database\ScoreDatabase.cs" />
     <Compile Include="Graphics\Backgrounds\Triangles.cs" />
     <Compile Include="Graphics\Cursor\CursorTrail.cs" />

From 77a4a896c96e762c07531cfa01dcdbd54564c1ec Mon Sep 17 00:00:00 2001
From: smoogipooo <smoogipooo@gmail.com>
Date: Sun, 12 Mar 2017 01:08:34 +0900
Subject: [PATCH 2/7] Cleanups.

---
 osu.Game/Beatmaps/Beatmap.cs     | 60 +++++++++++---------------------
 osu.Game/Beatmaps/BeatmapBase.cs | 51 +++++++++++++++++++++++++++
 osu.Game/osu.Game.csproj         |  1 +
 3 files changed, 72 insertions(+), 40 deletions(-)
 create mode 100644 osu.Game/Beatmaps/BeatmapBase.cs

diff --git a/osu.Game/Beatmaps/Beatmap.cs b/osu.Game/Beatmaps/Beatmap.cs
index 39b9fd13b8..1fa4a1f7b8 100644
--- a/osu.Game/Beatmaps/Beatmap.cs
+++ b/osu.Game/Beatmaps/Beatmap.cs
@@ -1,7 +1,6 @@
 // Copyright (c) 2007-2017 ppy Pty Ltd <contact@ppy.sh>.
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
-using OpenTK.Graphics;
 using osu.Game.Beatmaps.Timing;
 using osu.Game.Database;
 using osu.Game.Modes;
@@ -11,47 +10,21 @@ using System.Linq;
 
 namespace osu.Game.Beatmaps
 {
-    public class BeatmapBase
-    {
-        private BeatmapBase original;
-
-        public BeatmapBase(BeatmapBase original = null)
-        {
-            this.original = original;
-        }
-
-        private BeatmapInfo beatmapInfo;
-        public BeatmapInfo BeatmapInfo
-        {
-            get { return beatmapInfo ?? original?.BeatmapInfo; }
-            set { beatmapInfo = value; }
-        }
-
-        private List<ControlPoint> controlPoints;
-        public List<ControlPoint> ControlPoints
-        {
-            get { return controlPoints ?? original?.ControlPoints; }
-            set { controlPoints = value; }
-        }
-
-        private List<Color4> comboColors;
-        public List<Color4> ComboColors
-        {
-            get { return comboColors ?? original?.ComboColors; }
-            set { comboColors = value; }
-        }
-
-        public BeatmapMetadata Metadata => BeatmapInfo?.Metadata ?? BeatmapInfo?.BeatmapSet?.Metadata;
-    }
-
     /// <summary>
-    /// A generic beatmap that does not contain HitObjects.
+    /// A Beatmap containing HitObjects.
     /// </summary>
     public class Beatmap<T> : BeatmapBase
         where T : HitObject
     {
+        /// <summary>
+        /// The HitObjects this Beatmap contains.
+        /// </summary>
         public List<T> HitObjects;
 
+        /// <summary>
+        /// Constructs a new Beatmap containing HitObjects.
+        /// </summary>
+        /// <param name="original">If this Beatmap is a convert, the original Beatmap to use the properties of.</param>
         public Beatmap(BeatmapBase original = null)
             : base(original)
         {
@@ -99,15 +72,22 @@ namespace osu.Game.Beatmaps
         }
     }
 
+    /// <summary>
+    /// A Beatmap containing un-converted HitObjects.
+    /// </summary>
     public class Beatmap : Beatmap<HitObject>
     {
-        public Beatmap(BeatmapBase original = null)
-            : base(original)
-        {
-        }
-
+        /// <summary>
+        /// Calculates the star difficulty for this Beatmap.
+        /// </summary>
+        /// <returns>The star difficulty.</returns>
         public double CalculateStarDifficulty() => Ruleset.GetRuleset(BeatmapInfo.Mode).CreateDifficultyCalculator(this).Calculate();
 
+        /// <summary>
+        /// Converts this Beatmap to a <see cref="Beatmap{T}"/> containing another type of <see cref="HitObject"/>.
+        /// </summary>
+        /// <typeparam name="T">The type of HitObject the new Beatmap should contain.</typeparam>
+        /// <returns></returns>
         public Beatmap<T> ConvertTo<T>() where T : HitObject
         {
             return Ruleset.GetRuleset(BeatmapInfo.Mode).CreateBeatmapConverter<T>().Convert(this);
diff --git a/osu.Game/Beatmaps/BeatmapBase.cs b/osu.Game/Beatmaps/BeatmapBase.cs
new file mode 100644
index 0000000000..f7256f4a54
--- /dev/null
+++ b/osu.Game/Beatmaps/BeatmapBase.cs
@@ -0,0 +1,51 @@
+// Copyright (c) 2007-2017 ppy Pty Ltd <contact@ppy.sh>.
+// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
+
+using OpenTK.Graphics;
+using osu.Game.Beatmaps.Timing;
+using osu.Game.Database;
+using System.Collections.Generic;
+
+namespace osu.Game.Beatmaps
+{
+    /// <summary>
+    /// Contains basic beatmap properties.
+    /// <para>
+    /// This allows converted beatmaps (<see cref="Beatmap{T}"/>) to refer to an original "base" Beatmap
+    /// for properties that shouldn't change unless in exceptional circumstances.
+    /// Properties here may be set to be overriden in such exceptional cases.
+    /// </para>
+    /// </summary>
+    public class BeatmapBase
+    {
+        private BeatmapBase original;
+
+        public BeatmapBase(BeatmapBase original = null)
+        {
+            this.original = original;
+        }
+
+        private BeatmapInfo beatmapInfo;
+        public BeatmapInfo BeatmapInfo
+        {
+            get { return beatmapInfo ?? original?.BeatmapInfo; }
+            set { beatmapInfo = value; }
+        }
+
+        private List<ControlPoint> controlPoints;
+        public List<ControlPoint> ControlPoints
+        {
+            get { return controlPoints ?? original?.ControlPoints; }
+            set { controlPoints = value; }
+        }
+
+        private List<Color4> comboColors;
+        public List<Color4> ComboColors
+        {
+            get { return comboColors ?? original?.ComboColors; }
+            set { comboColors = value; }
+        }
+
+        public BeatmapMetadata Metadata => BeatmapInfo?.Metadata ?? BeatmapInfo?.BeatmapSet?.Metadata;
+    }
+}
diff --git a/osu.Game/osu.Game.csproj b/osu.Game/osu.Game.csproj
index 3d4a763cb8..c3097437c4 100644
--- a/osu.Game/osu.Game.csproj
+++ b/osu.Game/osu.Game.csproj
@@ -71,6 +71,7 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="Beatmaps\BeatmapBase.cs" />
     <Compile Include="Beatmaps\Drawables\BeatmapBackgroundSprite.cs" />
     <Compile Include="Beatmaps\DifficultyCalculator.cs" />
     <Compile Include="Beatmaps\IBeatmapCoverter.cs" />

From 1c7a9e3a07a9a60053b094aca6c028d44c19259f Mon Sep 17 00:00:00 2001
From: smoogipooo <smoogipooo@gmail.com>
Date: Sun, 12 Mar 2017 01:26:07 +0900
Subject: [PATCH 3/7] General fixups.

---
 osu.Game.Modes.Catch/CatchRuleset.cs              | 4 ++--
 osu.Game.Modes.Mania/ManiaDifficultyCalculator.cs | 6 ++----
 osu.Game.Modes.Mania/ManiaRuleset.cs              | 4 ++--
 osu.Game.Modes.Osu/OsuRuleset.cs                  | 4 ++--
 osu.Game.Modes.Taiko/TaikoRuleset.cs              | 4 ++--
 osu.Game/Beatmaps/Beatmap.cs                      | 1 -
 6 files changed, 10 insertions(+), 13 deletions(-)

diff --git a/osu.Game.Modes.Catch/CatchRuleset.cs b/osu.Game.Modes.Catch/CatchRuleset.cs
index 2cdd35cf3a..f3eda9ff37 100644
--- a/osu.Game.Modes.Catch/CatchRuleset.cs
+++ b/osu.Game.Modes.Catch/CatchRuleset.cs
@@ -93,9 +93,9 @@ namespace osu.Game.Modes.Catch
 
         public override DifficultyCalculator CreateDifficultyCalculator(Beatmap beatmap) => new CatchDifficultyCalculator(beatmap);
 
-        public override IBeatmapConverter<CatchBaseHit> CreateBeatmapConverter<CatchBaseHit>()
+        public override IBeatmapConverter<T> CreateBeatmapConverter<T>()
         {
-            return (IBeatmapConverter<CatchBaseHit>)new CatchBeatmapConverter();
+            return (IBeatmapConverter<T>)new CatchBeatmapConverter();
         }
     }
 }
diff --git a/osu.Game.Modes.Mania/ManiaDifficultyCalculator.cs b/osu.Game.Modes.Mania/ManiaDifficultyCalculator.cs
index 07c0749904..7ee93b84cf 100644
--- a/osu.Game.Modes.Mania/ManiaDifficultyCalculator.cs
+++ b/osu.Game.Modes.Mania/ManiaDifficultyCalculator.cs
@@ -12,11 +12,9 @@ namespace osu.Game.Modes.Mania
     {
         protected override PlayMode PlayMode => PlayMode.Mania;
 
-        private int columns;
-
-        public ManiaDifficultyCalculator(Beatmap beatmap, int columns = 5) : base(beatmap)
+        public ManiaDifficultyCalculator(Beatmap beatmap)
+            : base(beatmap)
         {
-            this.columns = columns;
         }
 
         protected override double CalculateInternal(Dictionary<String, String> categoryDifficulty)
diff --git a/osu.Game.Modes.Mania/ManiaRuleset.cs b/osu.Game.Modes.Mania/ManiaRuleset.cs
index 7d88942798..0aef44cd7b 100644
--- a/osu.Game.Modes.Mania/ManiaRuleset.cs
+++ b/osu.Game.Modes.Mania/ManiaRuleset.cs
@@ -108,9 +108,9 @@ namespace osu.Game.Modes.Mania
 
         public override DifficultyCalculator CreateDifficultyCalculator(Beatmap beatmap) => new ManiaDifficultyCalculator(beatmap);
 
-        public override IBeatmapConverter<ManiaBaseHit> CreateBeatmapConverter<ManiaBaseHit>()
+        public override IBeatmapConverter<T> CreateBeatmapConverter<T>()
         {
-            return (IBeatmapConverter<ManiaBaseHit>)new ManiaBeatmapConverter();
+            return (IBeatmapConverter<T>)new ManiaBeatmapConverter();
         }
     }
 }
diff --git a/osu.Game.Modes.Osu/OsuRuleset.cs b/osu.Game.Modes.Osu/OsuRuleset.cs
index 33427e0f55..a61bda5bb3 100644
--- a/osu.Game.Modes.Osu/OsuRuleset.cs
+++ b/osu.Game.Modes.Osu/OsuRuleset.cs
@@ -120,9 +120,9 @@ namespace osu.Game.Modes.Osu
             new KeyCounterMouse(MouseButton.Right)
         };
 
-        public override IBeatmapConverter<OsuHitObject> CreateBeatmapConverter<OsuHitObject>()
+        public override IBeatmapConverter<T> CreateBeatmapConverter<T>()
         {
-            return (IBeatmapConverter<OsuHitObject>)new OsuBeatmapConverter();
+            return (IBeatmapConverter<T>)new OsuBeatmapConverter();
         }
     }
 }
diff --git a/osu.Game.Modes.Taiko/TaikoRuleset.cs b/osu.Game.Modes.Taiko/TaikoRuleset.cs
index 4bca82a70b..3765862229 100644
--- a/osu.Game.Modes.Taiko/TaikoRuleset.cs
+++ b/osu.Game.Modes.Taiko/TaikoRuleset.cs
@@ -94,9 +94,9 @@ namespace osu.Game.Modes.Taiko
 
         public override DifficultyCalculator CreateDifficultyCalculator(Beatmap beatmap) => new TaikoDifficultyCalculator(beatmap);
 
-        public override IBeatmapConverter<TaikoBaseHit> CreateBeatmapConverter<TaikoBaseHit>()
+        public override IBeatmapConverter<T> CreateBeatmapConverter<T>()
         {
-            return (IBeatmapConverter<TaikoBaseHit>)new TaikoBeatmapConverter();
+            return (IBeatmapConverter<T>)new TaikoBeatmapConverter();
         }
     }
 }
diff --git a/osu.Game/Beatmaps/Beatmap.cs b/osu.Game/Beatmaps/Beatmap.cs
index 1fa4a1f7b8..94a56231f0 100644
--- a/osu.Game/Beatmaps/Beatmap.cs
+++ b/osu.Game/Beatmaps/Beatmap.cs
@@ -2,7 +2,6 @@
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
 using osu.Game.Beatmaps.Timing;
-using osu.Game.Database;
 using osu.Game.Modes;
 using osu.Game.Modes.Objects;
 using System.Collections.Generic;

From b0ea282a064473eed6d55808ba6fba620319227f Mon Sep 17 00:00:00 2001
From: smoogipooo <smoogipooo@gmail.com>
Date: Sun, 12 Mar 2017 02:26:10 +0900
Subject: [PATCH 4/7] Fix map would always be converted to itself when actually
 converting to a different game mode.

---
 osu.Game.Modes.Catch/UI/CatchHitRenderer.cs | 2 ++
 osu.Game.Modes.Mania/UI/ManiaHitRenderer.cs | 2 ++
 osu.Game.Modes.Osu/UI/OsuHitRenderer.cs     | 2 ++
 osu.Game.Modes.Taiko/UI/TaikoHitRenderer.cs | 2 ++
 osu.Game/Beatmaps/Beatmap.cs                | 4 ++--
 osu.Game/Beatmaps/DifficultyCalculator.cs   | 2 +-
 osu.Game/Modes/UI/HitRenderer.cs            | 5 +++--
 7 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/osu.Game.Modes.Catch/UI/CatchHitRenderer.cs b/osu.Game.Modes.Catch/UI/CatchHitRenderer.cs
index 703eb6fe91..990ec083cb 100644
--- a/osu.Game.Modes.Catch/UI/CatchHitRenderer.cs
+++ b/osu.Game.Modes.Catch/UI/CatchHitRenderer.cs
@@ -15,6 +15,8 @@ namespace osu.Game.Modes.Catch.UI
         {
         }
 
+        protected override PlayMode PlayMode => PlayMode.Catch;
+
         protected override Playfield<CatchBaseHit> CreatePlayfield() => new CatchPlayfield();
 
         protected override DrawableHitObject<CatchBaseHit> GetVisualRepresentation(CatchBaseHit h) => null;// new DrawableFruit(h);
diff --git a/osu.Game.Modes.Mania/UI/ManiaHitRenderer.cs b/osu.Game.Modes.Mania/UI/ManiaHitRenderer.cs
index 33b82738f8..916d919851 100644
--- a/osu.Game.Modes.Mania/UI/ManiaHitRenderer.cs
+++ b/osu.Game.Modes.Mania/UI/ManiaHitRenderer.cs
@@ -18,6 +18,8 @@ namespace osu.Game.Modes.Mania.UI
             this.columns = columns;
         }
 
+        protected override PlayMode PlayMode => PlayMode.Mania;
+
         protected override Playfield<ManiaBaseHit> CreatePlayfield() => new ManiaPlayfield(columns);
 
         protected override DrawableHitObject<ManiaBaseHit> GetVisualRepresentation(ManiaBaseHit h)
diff --git a/osu.Game.Modes.Osu/UI/OsuHitRenderer.cs b/osu.Game.Modes.Osu/UI/OsuHitRenderer.cs
index 118f96e145..040543fe1b 100644
--- a/osu.Game.Modes.Osu/UI/OsuHitRenderer.cs
+++ b/osu.Game.Modes.Osu/UI/OsuHitRenderer.cs
@@ -16,6 +16,8 @@ namespace osu.Game.Modes.Osu.UI
         {
         }
 
+        protected override PlayMode PlayMode => PlayMode.Osu;
+
         protected override Playfield<OsuHitObject> CreatePlayfield() => new OsuPlayfield();
 
         protected override DrawableHitObject<OsuHitObject> GetVisualRepresentation(OsuHitObject h)
diff --git a/osu.Game.Modes.Taiko/UI/TaikoHitRenderer.cs b/osu.Game.Modes.Taiko/UI/TaikoHitRenderer.cs
index e7d0372f43..365ab94dcb 100644
--- a/osu.Game.Modes.Taiko/UI/TaikoHitRenderer.cs
+++ b/osu.Game.Modes.Taiko/UI/TaikoHitRenderer.cs
@@ -15,6 +15,8 @@ namespace osu.Game.Modes.Taiko.UI
         {
         }
 
+        protected override PlayMode PlayMode => PlayMode.Taiko;
+
         protected override Playfield<TaikoBaseHit> CreatePlayfield() => new TaikoPlayfield();
 
         protected override DrawableHitObject<TaikoBaseHit> GetVisualRepresentation(TaikoBaseHit h) => null;// new DrawableTaikoHit(h);
diff --git a/osu.Game/Beatmaps/Beatmap.cs b/osu.Game/Beatmaps/Beatmap.cs
index 94a56231f0..99a212adf4 100644
--- a/osu.Game/Beatmaps/Beatmap.cs
+++ b/osu.Game/Beatmaps/Beatmap.cs
@@ -87,9 +87,9 @@ namespace osu.Game.Beatmaps
         /// </summary>
         /// <typeparam name="T">The type of HitObject the new Beatmap should contain.</typeparam>
         /// <returns></returns>
-        public Beatmap<T> ConvertTo<T>() where T : HitObject
+        public Beatmap<T> ConvertTo<T>(PlayMode playMode) where T : HitObject
         {
-            return Ruleset.GetRuleset(BeatmapInfo.Mode).CreateBeatmapConverter<T>().Convert(this);
+            return Ruleset.GetRuleset(playMode).CreateBeatmapConverter<T>().Convert(this);
         }
     }
 }
diff --git a/osu.Game/Beatmaps/DifficultyCalculator.cs b/osu.Game/Beatmaps/DifficultyCalculator.cs
index cb021b7490..1443d55068 100644
--- a/osu.Game/Beatmaps/DifficultyCalculator.cs
+++ b/osu.Game/Beatmaps/DifficultyCalculator.cs
@@ -37,7 +37,7 @@ namespace osu.Game.Beatmaps
 
         protected DifficultyCalculator(Beatmap beatmap)
         {
-            Objects = beatmap.ConvertTo<T>().HitObjects;
+            Objects = beatmap.ConvertTo<T>(PlayMode).HitObjects;
             PreprocessHitObjects();
         }
 
diff --git a/osu.Game/Modes/UI/HitRenderer.cs b/osu.Game/Modes/UI/HitRenderer.cs
index 68b4c6d022..c7c1c82781 100644
--- a/osu.Game/Modes/UI/HitRenderer.cs
+++ b/osu.Game/Modes/UI/HitRenderer.cs
@@ -50,15 +50,16 @@ namespace osu.Game.Modes.UI
         protected override Container<Drawable> Content => content;
         protected override bool AllObjectsJudged => Playfield.HitObjects.Children.All(h => h.Judgement.Result.HasValue);
 
-        protected Playfield<TObject> Playfield;
+        protected abstract PlayMode PlayMode { get; }
 
+        protected Playfield<TObject> Playfield;
         protected Beatmap<TObject> Beatmap;
 
         private Container content;
 
         protected HitRenderer(Beatmap beatmap)
         {
-            Beatmap = beatmap.ConvertTo<TObject>();
+            Beatmap = beatmap.ConvertTo<TObject>(PlayMode);
 
             RelativeSizeAxes = Axes.Both;
 

From 3480dca0add9b9b28ea0e5fe672f1c67939b4c13 Mon Sep 17 00:00:00 2001
From: smoogipooo <smoogipooo@gmail.com>
Date: Sun, 12 Mar 2017 14:32:50 +0900
Subject: [PATCH 5/7] Remove PlayMode enum requirement. Clean things up a lot.

---
 .../CatchDifficultyCalculator.cs              |  7 +--
 osu.Game.Modes.Catch/CatchRuleset.cs          |  4 +-
 osu.Game.Modes.Catch/UI/CatchHitRenderer.cs   |  3 +-
 .../ManiaDifficultyCalculator.cs              |  8 +--
 osu.Game.Modes.Mania/UI/ManiaHitRenderer.cs   |  3 +-
 osu.Game.Modes.Osu/OsuDifficultyCalculator.cs |  7 +--
 osu.Game.Modes.Osu/UI/OsuHitRenderer.cs       |  3 +-
 .../TaikoDifficultyCalculator.cs              |  8 +--
 osu.Game.Modes.Taiko/UI/TaikoHitRenderer.cs   |  3 +-
 osu.Game/Beatmaps/Beatmap.cs                  | 32 ++++++------
 osu.Game/Beatmaps/BeatmapBase.cs              | 51 -------------------
 osu.Game/Beatmaps/DifficultyCalculator.cs     | 10 ++--
 osu.Game/Database/BeatmapInfo.cs              |  6 +--
 osu.Game/Modes/UI/HitRenderer.cs              |  5 +-
 osu.Game/osu.Game.csproj                      |  1 -
 15 files changed, 51 insertions(+), 100 deletions(-)
 delete mode 100644 osu.Game/Beatmaps/BeatmapBase.cs

diff --git a/osu.Game.Modes.Catch/CatchDifficultyCalculator.cs b/osu.Game.Modes.Catch/CatchDifficultyCalculator.cs
index 01fa1a00d4..c85cb8a8f1 100644
--- a/osu.Game.Modes.Catch/CatchDifficultyCalculator.cs
+++ b/osu.Game.Modes.Catch/CatchDifficultyCalculator.cs
@@ -2,6 +2,7 @@
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
 using osu.Game.Beatmaps;
+using osu.Game.Modes.Catch.Beatmaps;
 using osu.Game.Modes.Catch.Objects;
 using System;
 using System.Collections.Generic;
@@ -10,15 +11,15 @@ namespace osu.Game.Modes.Catch
 {
     public class CatchDifficultyCalculator : DifficultyCalculator<CatchBaseHit>
     {
-        protected override PlayMode PlayMode => PlayMode.Catch;
-
         public CatchDifficultyCalculator(Beatmap beatmap) : base(beatmap)
         {
         }
 
-        protected override double CalculateInternal(Dictionary<String, String> categoryDifficulty)
+        protected override double CalculateInternal(Dictionary<string, string> categoryDifficulty)
         {
             return 0;
         }
+
+        protected override IBeatmapConverter<CatchBaseHit> CreateBeatmapConverter() => new CatchBeatmapConverter();
     }
 }
\ No newline at end of file
diff --git a/osu.Game.Modes.Catch/CatchRuleset.cs b/osu.Game.Modes.Catch/CatchRuleset.cs
index f3eda9ff37..2cdd35cf3a 100644
--- a/osu.Game.Modes.Catch/CatchRuleset.cs
+++ b/osu.Game.Modes.Catch/CatchRuleset.cs
@@ -93,9 +93,9 @@ namespace osu.Game.Modes.Catch
 
         public override DifficultyCalculator CreateDifficultyCalculator(Beatmap beatmap) => new CatchDifficultyCalculator(beatmap);
 
-        public override IBeatmapConverter<T> CreateBeatmapConverter<T>()
+        public override IBeatmapConverter<CatchBaseHit> CreateBeatmapConverter<CatchBaseHit>()
         {
-            return (IBeatmapConverter<T>)new CatchBeatmapConverter();
+            return (IBeatmapConverter<CatchBaseHit>)new CatchBeatmapConverter();
         }
     }
 }
diff --git a/osu.Game.Modes.Catch/UI/CatchHitRenderer.cs b/osu.Game.Modes.Catch/UI/CatchHitRenderer.cs
index 990ec083cb..1537227d8f 100644
--- a/osu.Game.Modes.Catch/UI/CatchHitRenderer.cs
+++ b/osu.Game.Modes.Catch/UI/CatchHitRenderer.cs
@@ -2,6 +2,7 @@
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
 using osu.Game.Beatmaps;
+using osu.Game.Modes.Catch.Beatmaps;
 using osu.Game.Modes.Catch.Objects;
 using osu.Game.Modes.Objects.Drawables;
 using osu.Game.Modes.UI;
@@ -15,7 +16,7 @@ namespace osu.Game.Modes.Catch.UI
         {
         }
 
-        protected override PlayMode PlayMode => PlayMode.Catch;
+        protected override IBeatmapConverter<CatchBaseHit> CreateBeatmapConverter() => new CatchBeatmapConverter();
 
         protected override Playfield<CatchBaseHit> CreatePlayfield() => new CatchPlayfield();
 
diff --git a/osu.Game.Modes.Mania/ManiaDifficultyCalculator.cs b/osu.Game.Modes.Mania/ManiaDifficultyCalculator.cs
index 7ee93b84cf..02a5a3acdc 100644
--- a/osu.Game.Modes.Mania/ManiaDifficultyCalculator.cs
+++ b/osu.Game.Modes.Mania/ManiaDifficultyCalculator.cs
@@ -2,24 +2,24 @@
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
 using osu.Game.Beatmaps;
+using osu.Game.Modes.Mania.Beatmaps;
 using osu.Game.Modes.Mania.Objects;
-using System;
 using System.Collections.Generic;
 
 namespace osu.Game.Modes.Mania
 {
     public class ManiaDifficultyCalculator : DifficultyCalculator<ManiaBaseHit>
     {
-        protected override PlayMode PlayMode => PlayMode.Mania;
-
         public ManiaDifficultyCalculator(Beatmap beatmap)
             : base(beatmap)
         {
         }
 
-        protected override double CalculateInternal(Dictionary<String, String> categoryDifficulty)
+        protected override double CalculateInternal(Dictionary<string, string> categoryDifficulty)
         {
             return 0;
         }
+
+        protected override IBeatmapConverter<ManiaBaseHit> CreateBeatmapConverter() => new ManiaBeatmapConverter();
     }
 }
\ No newline at end of file
diff --git a/osu.Game.Modes.Mania/UI/ManiaHitRenderer.cs b/osu.Game.Modes.Mania/UI/ManiaHitRenderer.cs
index 916d919851..911742b222 100644
--- a/osu.Game.Modes.Mania/UI/ManiaHitRenderer.cs
+++ b/osu.Game.Modes.Mania/UI/ManiaHitRenderer.cs
@@ -2,6 +2,7 @@
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
 using osu.Game.Beatmaps;
+using osu.Game.Modes.Mania.Beatmaps;
 using osu.Game.Modes.Mania.Objects;
 using osu.Game.Modes.Objects.Drawables;
 using osu.Game.Modes.UI;
@@ -18,7 +19,7 @@ namespace osu.Game.Modes.Mania.UI
             this.columns = columns;
         }
 
-        protected override PlayMode PlayMode => PlayMode.Mania;
+        protected override IBeatmapConverter<ManiaBaseHit> CreateBeatmapConverter() => new ManiaBeatmapConverter();
 
         protected override Playfield<ManiaBaseHit> CreatePlayfield() => new ManiaPlayfield(columns);
 
diff --git a/osu.Game.Modes.Osu/OsuDifficultyCalculator.cs b/osu.Game.Modes.Osu/OsuDifficultyCalculator.cs
index 86c6596138..5ef0f0059d 100644
--- a/osu.Game.Modes.Osu/OsuDifficultyCalculator.cs
+++ b/osu.Game.Modes.Osu/OsuDifficultyCalculator.cs
@@ -2,6 +2,7 @@
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
 using osu.Game.Beatmaps;
+using osu.Game.Modes.Osu.Beatmaps;
 using osu.Game.Modes.Osu.Objects;
 using System;
 using System.Collections.Generic;
@@ -13,8 +14,6 @@ namespace osu.Game.Modes.Osu
         private const double star_scaling_factor = 0.0675;
         private const double extreme_scaling_factor = 0.5;
 
-        protected override PlayMode PlayMode => PlayMode.Osu;
-
         /// <summary>
         /// HitObjects are stored as a member variable.
         /// </summary>
@@ -31,7 +30,7 @@ namespace osu.Game.Modes.Osu
                     ((Slider)h).Curve.Calculate();
         }
 
-        protected override double CalculateInternal(Dictionary<String, String> categoryDifficulty)
+        protected override double CalculateInternal(Dictionary<string, string> categoryDifficulty)
         {
             // Fill our custom DifficultyHitObject class, that carries additional information
             DifficultyHitObjects.Clear();
@@ -181,6 +180,8 @@ namespace osu.Game.Modes.Osu
             return difficulty;
         }
 
+        protected override IBeatmapConverter<OsuHitObject> CreateBeatmapConverter() => new OsuBeatmapConverter();
+
         // Those values are used as array indices. Be careful when changing them!
         public enum DifficultyType
         {
diff --git a/osu.Game.Modes.Osu/UI/OsuHitRenderer.cs b/osu.Game.Modes.Osu/UI/OsuHitRenderer.cs
index 040543fe1b..8b7606e61e 100644
--- a/osu.Game.Modes.Osu/UI/OsuHitRenderer.cs
+++ b/osu.Game.Modes.Osu/UI/OsuHitRenderer.cs
@@ -3,6 +3,7 @@
 
 using osu.Game.Beatmaps;
 using osu.Game.Modes.Objects.Drawables;
+using osu.Game.Modes.Osu.Beatmaps;
 using osu.Game.Modes.Osu.Objects;
 using osu.Game.Modes.Osu.Objects.Drawables;
 using osu.Game.Modes.UI;
@@ -16,7 +17,7 @@ namespace osu.Game.Modes.Osu.UI
         {
         }
 
-        protected override PlayMode PlayMode => PlayMode.Osu;
+        protected override IBeatmapConverter<OsuHitObject> CreateBeatmapConverter() => new OsuBeatmapConverter();
 
         protected override Playfield<OsuHitObject> CreatePlayfield() => new OsuPlayfield();
 
diff --git a/osu.Game.Modes.Taiko/TaikoDifficultyCalculator.cs b/osu.Game.Modes.Taiko/TaikoDifficultyCalculator.cs
index a90e2f40fa..4a133ea896 100644
--- a/osu.Game.Modes.Taiko/TaikoDifficultyCalculator.cs
+++ b/osu.Game.Modes.Taiko/TaikoDifficultyCalculator.cs
@@ -2,23 +2,23 @@
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
 using osu.Game.Beatmaps;
+using osu.Game.Modes.Taiko.Beatmaps;
 using osu.Game.Modes.Taiko.Objects;
-using System;
 using System.Collections.Generic;
 
 namespace osu.Game.Modes.Taiko
 {
     public class TaikoDifficultyCalculator : DifficultyCalculator<TaikoBaseHit>
     {
-        protected override PlayMode PlayMode => PlayMode.Taiko;
-
         public TaikoDifficultyCalculator(Beatmap beatmap) : base(beatmap)
         {
         }
 
-        protected override double CalculateInternal(Dictionary<String, String> categoryDifficulty)
+        protected override double CalculateInternal(Dictionary<string, string> categoryDifficulty)
         {
             return 0;
         }
+
+        protected override IBeatmapConverter<TaikoBaseHit> CreateBeatmapConverter() => new TaikoBeatmapConverter();
     }
 }
\ No newline at end of file
diff --git a/osu.Game.Modes.Taiko/UI/TaikoHitRenderer.cs b/osu.Game.Modes.Taiko/UI/TaikoHitRenderer.cs
index 365ab94dcb..dc0276aacc 100644
--- a/osu.Game.Modes.Taiko/UI/TaikoHitRenderer.cs
+++ b/osu.Game.Modes.Taiko/UI/TaikoHitRenderer.cs
@@ -3,6 +3,7 @@
 
 using osu.Game.Beatmaps;
 using osu.Game.Modes.Objects.Drawables;
+using osu.Game.Modes.Taiko.Beatmaps;
 using osu.Game.Modes.Taiko.Objects;
 using osu.Game.Modes.UI;
 
@@ -15,7 +16,7 @@ namespace osu.Game.Modes.Taiko.UI
         {
         }
 
-        protected override PlayMode PlayMode => PlayMode.Taiko;
+        protected override IBeatmapConverter<TaikoBaseHit> CreateBeatmapConverter() => new TaikoBeatmapConverter();
 
         protected override Playfield<TaikoBaseHit> CreatePlayfield() => new TaikoPlayfield();
 
diff --git a/osu.Game/Beatmaps/Beatmap.cs b/osu.Game/Beatmaps/Beatmap.cs
index 99a212adf4..de869192b9 100644
--- a/osu.Game/Beatmaps/Beatmap.cs
+++ b/osu.Game/Beatmaps/Beatmap.cs
@@ -1,7 +1,9 @@
 // Copyright (c) 2007-2017 ppy Pty Ltd <contact@ppy.sh>.
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
+using OpenTK.Graphics;
 using osu.Game.Beatmaps.Timing;
+using osu.Game.Database;
 using osu.Game.Modes;
 using osu.Game.Modes.Objects;
 using System.Collections.Generic;
@@ -10,23 +12,31 @@ using System.Linq;
 namespace osu.Game.Beatmaps
 {
     /// <summary>
-    /// A Beatmap containing HitObjects.
+    /// A Beatmap containing converted HitObjects.
     /// </summary>
-    public class Beatmap<T> : BeatmapBase
+    public class Beatmap<T>
         where T : HitObject
     {
+        public BeatmapInfo BeatmapInfo;
+        public List<ControlPoint> ControlPoints;
+        public List<Color4> ComboColors;
+
+        public BeatmapMetadata Metadata => BeatmapInfo?.Metadata ?? BeatmapInfo?.BeatmapSet?.Metadata;
+
         /// <summary>
         /// The HitObjects this Beatmap contains.
         /// </summary>
         public List<T> HitObjects;
 
         /// <summary>
-        /// Constructs a new Beatmap containing HitObjects.
+        /// Constructs a new beatmap.
         /// </summary>
-        /// <param name="original">If this Beatmap is a convert, the original Beatmap to use the properties of.</param>
-        public Beatmap(BeatmapBase original = null)
-            : base(original)
+        /// <param name="original">The original beatmap to use the parameters of.</param>
+        public Beatmap(Beatmap original = null)
         {
+            BeatmapInfo = original?.BeatmapInfo;
+            ControlPoints = original?.ControlPoints;
+            ComboColors = original?.ComboColors;
         }
 
         public double BPMMaximum => 60000 / (ControlPoints?.Where(c => c.BeatLength != 0).OrderBy(c => c.BeatLength).FirstOrDefault() ?? ControlPoint.Default).BeatLength;
@@ -81,15 +91,5 @@ namespace osu.Game.Beatmaps
         /// </summary>
         /// <returns>The star difficulty.</returns>
         public double CalculateStarDifficulty() => Ruleset.GetRuleset(BeatmapInfo.Mode).CreateDifficultyCalculator(this).Calculate();
-
-        /// <summary>
-        /// Converts this Beatmap to a <see cref="Beatmap{T}"/> containing another type of <see cref="HitObject"/>.
-        /// </summary>
-        /// <typeparam name="T">The type of HitObject the new Beatmap should contain.</typeparam>
-        /// <returns></returns>
-        public Beatmap<T> ConvertTo<T>(PlayMode playMode) where T : HitObject
-        {
-            return Ruleset.GetRuleset(playMode).CreateBeatmapConverter<T>().Convert(this);
-        }
     }
 }
diff --git a/osu.Game/Beatmaps/BeatmapBase.cs b/osu.Game/Beatmaps/BeatmapBase.cs
deleted file mode 100644
index f7256f4a54..0000000000
--- a/osu.Game/Beatmaps/BeatmapBase.cs
+++ /dev/null
@@ -1,51 +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 OpenTK.Graphics;
-using osu.Game.Beatmaps.Timing;
-using osu.Game.Database;
-using System.Collections.Generic;
-
-namespace osu.Game.Beatmaps
-{
-    /// <summary>
-    /// Contains basic beatmap properties.
-    /// <para>
-    /// This allows converted beatmaps (<see cref="Beatmap{T}"/>) to refer to an original "base" Beatmap
-    /// for properties that shouldn't change unless in exceptional circumstances.
-    /// Properties here may be set to be overriden in such exceptional cases.
-    /// </para>
-    /// </summary>
-    public class BeatmapBase
-    {
-        private BeatmapBase original;
-
-        public BeatmapBase(BeatmapBase original = null)
-        {
-            this.original = original;
-        }
-
-        private BeatmapInfo beatmapInfo;
-        public BeatmapInfo BeatmapInfo
-        {
-            get { return beatmapInfo ?? original?.BeatmapInfo; }
-            set { beatmapInfo = value; }
-        }
-
-        private List<ControlPoint> controlPoints;
-        public List<ControlPoint> ControlPoints
-        {
-            get { return controlPoints ?? original?.ControlPoints; }
-            set { controlPoints = value; }
-        }
-
-        private List<Color4> comboColors;
-        public List<Color4> ComboColors
-        {
-            get { return comboColors ?? original?.ComboColors; }
-            set { comboColors = value; }
-        }
-
-        public BeatmapMetadata Metadata => BeatmapInfo?.Metadata ?? BeatmapInfo?.BeatmapSet?.Metadata;
-    }
-}
diff --git a/osu.Game/Beatmaps/DifficultyCalculator.cs b/osu.Game/Beatmaps/DifficultyCalculator.cs
index 1443d55068..9c057d5f77 100644
--- a/osu.Game/Beatmaps/DifficultyCalculator.cs
+++ b/osu.Game/Beatmaps/DifficultyCalculator.cs
@@ -1,20 +1,16 @@
 // 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.Game.Modes;
 using osu.Game.Modes.Objects;
-using System;
 using System.Collections.Generic;
 
 namespace osu.Game.Beatmaps
 {
     public abstract class DifficultyCalculator
     {
-        protected abstract PlayMode PlayMode { get; }
-
         protected double TimeRate = 1;
 
-        protected abstract double CalculateInternal(Dictionary<String, String> categoryDifficulty);
+        protected abstract double CalculateInternal(Dictionary<string, string> categoryDifficulty);
 
         private void loadTiming()
         {
@@ -37,12 +33,14 @@ namespace osu.Game.Beatmaps
 
         protected DifficultyCalculator(Beatmap beatmap)
         {
-            Objects = beatmap.ConvertTo<T>(PlayMode).HitObjects;
+            Objects = CreateBeatmapConverter().Convert(beatmap).HitObjects;
             PreprocessHitObjects();
         }
 
         protected virtual void PreprocessHitObjects()
         {
         }
+
+        protected abstract IBeatmapConverter<T> CreateBeatmapConverter();
     }
 }
diff --git a/osu.Game/Database/BeatmapInfo.cs b/osu.Game/Database/BeatmapInfo.cs
index 28c9e51d2a..017f34726b 100644
--- a/osu.Game/Database/BeatmapInfo.cs
+++ b/osu.Game/Database/BeatmapInfo.cs
@@ -1,12 +1,12 @@
 // 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;
-using System.Linq;
 using osu.Game.Beatmaps.Samples;
 using osu.Game.Modes;
 using SQLite.Net.Attributes;
 using SQLiteNetExtensions.Attributes;
+using System;
+using System.Linq;
 
 namespace osu.Game.Database
 {
@@ -82,7 +82,7 @@ namespace osu.Game.Database
             {
                 return starDifficulty < 0 ? (BaseDifficulty?.OverallDifficulty ?? 5) : starDifficulty;
             }
-            
+
             set { starDifficulty = value; }
         }
 
diff --git a/osu.Game/Modes/UI/HitRenderer.cs b/osu.Game/Modes/UI/HitRenderer.cs
index c7c1c82781..e08570522f 100644
--- a/osu.Game/Modes/UI/HitRenderer.cs
+++ b/osu.Game/Modes/UI/HitRenderer.cs
@@ -50,8 +50,6 @@ namespace osu.Game.Modes.UI
         protected override Container<Drawable> Content => content;
         protected override bool AllObjectsJudged => Playfield.HitObjects.Children.All(h => h.Judgement.Result.HasValue);
 
-        protected abstract PlayMode PlayMode { get; }
-
         protected Playfield<TObject> Playfield;
         protected Beatmap<TObject> Beatmap;
 
@@ -59,7 +57,7 @@ namespace osu.Game.Modes.UI
 
         protected HitRenderer(Beatmap beatmap)
         {
-            Beatmap = beatmap.ConvertTo<TObject>(PlayMode);
+            Beatmap = CreateBeatmapConverter().Convert(beatmap);
 
             RelativeSizeAxes = Axes.Both;
 
@@ -103,5 +101,6 @@ namespace osu.Game.Modes.UI
 
         protected abstract DrawableHitObject<TObject> GetVisualRepresentation(TObject h);
         protected abstract Playfield<TObject> CreatePlayfield();
+        protected abstract IBeatmapConverter<TObject> CreateBeatmapConverter();
     }
 }
diff --git a/osu.Game/osu.Game.csproj b/osu.Game/osu.Game.csproj
index c3097437c4..3d4a763cb8 100644
--- a/osu.Game/osu.Game.csproj
+++ b/osu.Game/osu.Game.csproj
@@ -71,7 +71,6 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
-    <Compile Include="Beatmaps\BeatmapBase.cs" />
     <Compile Include="Beatmaps\Drawables\BeatmapBackgroundSprite.cs" />
     <Compile Include="Beatmaps\DifficultyCalculator.cs" />
     <Compile Include="Beatmaps\IBeatmapCoverter.cs" />

From b47c9e808ef55827082840414dff9342c285e93c Mon Sep 17 00:00:00 2001
From: smoogipooo <smoogipooo@gmail.com>
Date: Sun, 12 Mar 2017 14:37:39 +0900
Subject: [PATCH 6/7] usings

---
 osu.Game.Modes.Catch/CatchDifficultyCalculator.cs | 1 -
 1 file changed, 1 deletion(-)

diff --git a/osu.Game.Modes.Catch/CatchDifficultyCalculator.cs b/osu.Game.Modes.Catch/CatchDifficultyCalculator.cs
index c85cb8a8f1..53c6f5c2ce 100644
--- a/osu.Game.Modes.Catch/CatchDifficultyCalculator.cs
+++ b/osu.Game.Modes.Catch/CatchDifficultyCalculator.cs
@@ -4,7 +4,6 @@
 using osu.Game.Beatmaps;
 using osu.Game.Modes.Catch.Beatmaps;
 using osu.Game.Modes.Catch.Objects;
-using System;
 using System.Collections.Generic;
 
 namespace osu.Game.Modes.Catch

From 5be1839710592d18e0d1ba0793f34e5b2c07f63b Mon Sep 17 00:00:00 2001
From: smoogipooo <smoogipooo@gmail.com>
Date: Sun, 12 Mar 2017 22:19:35 +0900
Subject: [PATCH 7/7] Remove unused method.

---
 osu.Game.Modes.Catch/CatchRuleset.cs | 6 ------
 osu.Game.Modes.Mania/ManiaRuleset.cs | 6 ------
 osu.Game.Modes.Osu/OsuRuleset.cs     | 6 ------
 osu.Game.Modes.Taiko/TaikoRuleset.cs | 6 ------
 osu.Game/Modes/Ruleset.cs            | 2 --
 5 files changed, 26 deletions(-)

diff --git a/osu.Game.Modes.Catch/CatchRuleset.cs b/osu.Game.Modes.Catch/CatchRuleset.cs
index 2cdd35cf3a..08edeb7bcb 100644
--- a/osu.Game.Modes.Catch/CatchRuleset.cs
+++ b/osu.Game.Modes.Catch/CatchRuleset.cs
@@ -4,7 +4,6 @@
 using OpenTK.Input;
 using osu.Game.Beatmaps;
 using osu.Game.Graphics;
-using osu.Game.Modes.Catch.Beatmaps;
 using osu.Game.Modes.Catch.UI;
 using osu.Game.Modes.Objects;
 using osu.Game.Modes.UI;
@@ -92,10 +91,5 @@ namespace osu.Game.Modes.Catch
         public override HitObjectParser CreateHitObjectParser() => new NullHitObjectParser();
 
         public override DifficultyCalculator CreateDifficultyCalculator(Beatmap beatmap) => new CatchDifficultyCalculator(beatmap);
-
-        public override IBeatmapConverter<CatchBaseHit> CreateBeatmapConverter<CatchBaseHit>()
-        {
-            return (IBeatmapConverter<CatchBaseHit>)new CatchBeatmapConverter();
-        }
     }
 }
diff --git a/osu.Game.Modes.Mania/ManiaRuleset.cs b/osu.Game.Modes.Mania/ManiaRuleset.cs
index 0aef44cd7b..e6e9cfd799 100644
--- a/osu.Game.Modes.Mania/ManiaRuleset.cs
+++ b/osu.Game.Modes.Mania/ManiaRuleset.cs
@@ -3,7 +3,6 @@
 
 using osu.Game.Beatmaps;
 using osu.Game.Graphics;
-using osu.Game.Modes.Mania.Beatmaps;
 using osu.Game.Modes.Mania.UI;
 using osu.Game.Modes.Objects;
 using osu.Game.Modes.UI;
@@ -107,10 +106,5 @@ namespace osu.Game.Modes.Mania
         public override HitObjectParser CreateHitObjectParser() => new NullHitObjectParser();
 
         public override DifficultyCalculator CreateDifficultyCalculator(Beatmap beatmap) => new ManiaDifficultyCalculator(beatmap);
-
-        public override IBeatmapConverter<T> CreateBeatmapConverter<T>()
-        {
-            return (IBeatmapConverter<T>)new ManiaBeatmapConverter();
-        }
     }
 }
diff --git a/osu.Game.Modes.Osu/OsuRuleset.cs b/osu.Game.Modes.Osu/OsuRuleset.cs
index a61bda5bb3..0c46ece6da 100644
--- a/osu.Game.Modes.Osu/OsuRuleset.cs
+++ b/osu.Game.Modes.Osu/OsuRuleset.cs
@@ -5,7 +5,6 @@ using OpenTK.Input;
 using osu.Game.Beatmaps;
 using osu.Game.Graphics;
 using osu.Game.Modes.Objects;
-using osu.Game.Modes.Osu.Beatmaps;
 using osu.Game.Modes.Osu.Objects;
 using osu.Game.Modes.Osu.UI;
 using osu.Game.Modes.UI;
@@ -119,10 +118,5 @@ namespace osu.Game.Modes.Osu
             new KeyCounterMouse(MouseButton.Left),
             new KeyCounterMouse(MouseButton.Right)
         };
-
-        public override IBeatmapConverter<T> CreateBeatmapConverter<T>()
-        {
-            return (IBeatmapConverter<T>)new OsuBeatmapConverter();
-        }
     }
 }
diff --git a/osu.Game.Modes.Taiko/TaikoRuleset.cs b/osu.Game.Modes.Taiko/TaikoRuleset.cs
index 3765862229..418519d90c 100644
--- a/osu.Game.Modes.Taiko/TaikoRuleset.cs
+++ b/osu.Game.Modes.Taiko/TaikoRuleset.cs
@@ -5,7 +5,6 @@ using OpenTK.Input;
 using osu.Game.Beatmaps;
 using osu.Game.Graphics;
 using osu.Game.Modes.Objects;
-using osu.Game.Modes.Taiko.Beatmaps;
 using osu.Game.Modes.Taiko.UI;
 using osu.Game.Modes.UI;
 using osu.Game.Screens.Play;
@@ -93,10 +92,5 @@ namespace osu.Game.Modes.Taiko
         public override HitObjectParser CreateHitObjectParser() => new NullHitObjectParser();
 
         public override DifficultyCalculator CreateDifficultyCalculator(Beatmap beatmap) => new TaikoDifficultyCalculator(beatmap);
-
-        public override IBeatmapConverter<T> CreateBeatmapConverter<T>()
-        {
-            return (IBeatmapConverter<T>)new TaikoBeatmapConverter();
-        }
     }
 }
diff --git a/osu.Game/Modes/Ruleset.cs b/osu.Game/Modes/Ruleset.cs
index 54137b2402..d8892e64e9 100644
--- a/osu.Game/Modes/Ruleset.cs
+++ b/osu.Game/Modes/Ruleset.cs
@@ -37,8 +37,6 @@ namespace osu.Game.Modes
 
         public abstract DifficultyCalculator CreateDifficultyCalculator(Beatmap beatmap);
 
-        public abstract IBeatmapConverter<T> CreateBeatmapConverter<T>() where T : HitObject;
-
         public static void Register(Ruleset ruleset) => availableRulesets.TryAdd(ruleset.PlayMode, ruleset.GetType());
 
         protected abstract PlayMode PlayMode { get; }