Better beatmap conversion model.

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
+            };
+        }
+    }
+}

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;

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();
+        }
     }
 }

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);

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" />

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
+            };
+        }
+    }
+}

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;

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();
+        }
     }
 }

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)

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.

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
                 }
             }
         }
-
     }
 }

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)

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();
+        }
     }
 }

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)

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" />

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
+            };
+        }
+    }
+}

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;

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();
+        }
     }
 }

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);

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" />

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);
+        }
     }
 }

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();
         }
 

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);
+    }
+}

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; }

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);
 

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" />