Implement basic Taiko HitObject conversion.

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

@@ -2,8 +2,12 @@
 // Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
 
 using osu.Game.Beatmaps;
+using osu.Game.Beatmaps.Legacy;
+using osu.Game.Modes.Objects;
+using osu.Game.Modes.Objects.Types;
 using osu.Game.Modes.Taiko.Objects;
 using System.Collections.Generic;
+using System.Linq;
 
 namespace osu.Game.Modes.Taiko.Beatmaps
 {
@@ -11,9 +15,52 @@ namespace osu.Game.Modes.Taiko.Beatmaps
     {
         public Beatmap<TaikoHitObject> Convert(Beatmap original)
         {
+            if (original is IIsLegacy)
+                original.TimingInfo.ControlPoints.ForEach(c => c.VelocityAdjustment *= 1.4);
+
             return new Beatmap<TaikoHitObject>(original)
             {
-                HitObjects = new List<TaikoHitObject>() // Todo: Implement
+                HitObjects = convertHitObjects(original.HitObjects)
+            };
+        }
+
+        private List<TaikoHitObject> convertHitObjects(List<HitObject> hitObjects)
+        {
+            return hitObjects.Select(convertHitObject).ToList();
+        }
+
+        private TaikoHitObject convertHitObject(HitObject original)
+        {
+            IHasDistance distanceData = original as IHasDistance;
+            IHasRepeats repeatsData = original as IHasRepeats;
+            IHasEndTime endTimeData = original as IHasEndTime;
+
+            if (distanceData != null)
+            {
+                return new DrumRoll
+                {
+                    StartTime = original.StartTime,
+                    Sample = original.Sample,
+
+                    Distance = distanceData.Distance * (repeatsData?.RepeatCount ?? 1)
+                };
+            }
+
+            if (endTimeData != null)
+            {
+                return new Bash
+                {
+                    StartTime = original.StartTime,
+                    Sample = original.Sample,
+
+                    EndTime = endTimeData.EndTime
+                };
+            }
+
+            return new TaikoHitObject
+            {
+                StartTime = original.StartTime,
+                Sample = original.Sample,
             };
         }
     }