Add very basic hitsound support.

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

@@ -18,13 +18,12 @@ namespace osu.Game.Modes.Osu.Objects.Drawables
         private List<ISliderProgress> components = new List<ISliderProgress>();
 
         SliderBody body;
+        SliderBall ball;
 
         SliderBouncer bouncer1, bouncer2;
 
         public DrawableSlider(Slider s) : base(s)
         {
-            SliderBall ball;
-
             slider = s;
 
             Origin = Anchor.TopLeft;
@@ -46,6 +45,7 @@ namespace osu.Game.Modes.Osu.Objects.Drawables
                     StartTime = s.StartTime,
                     Position = s.Position,
                     Colour = s.Colour,
+                    Sample = s.Sample,
                 })
                 {
                     Depth = -1 //override time-based depth.
@@ -58,6 +58,8 @@ namespace osu.Game.Modes.Osu.Objects.Drawables
             components.Add(bouncer2);
         }
 
+        int currentRepeat;
+
         protected override void Update()
         {
             base.Update();
@@ -67,6 +69,13 @@ namespace osu.Game.Modes.Osu.Objects.Drawables
             int repeat = (int)(progress * slider.RepeatCount);
             progress = (progress * slider.RepeatCount) % 1;
 
+            if (repeat > currentRepeat)
+            {
+                if (ball.Tracking)
+                    PlaySample();
+                currentRepeat = repeat;
+            }
+
             if (repeat % 2 == 1)
                 progress = 1 - progress;
 

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

@@ -84,7 +84,7 @@ namespace osu.Game.Modes.Osu.Objects.Drawables.Pieces
         }
 
         bool tracking;
-        protected bool Tracking
+        public bool Tracking
         {
             get { return tracking; }
             set

osu.Game.Mode.Osu/Objects/OsuHitObjectParser.cs

@@ -101,7 +101,10 @@ namespace osu.Game.Modes.Osu.Objects
             }
             result.Position = new Vector2(int.Parse(split[0]), int.Parse(split[1]));
             result.StartTime = double.Parse(split[2]);
-            result.Sample = new HitSampleInfo { Type = (SampleType)int.Parse(split[4]) };
+            result.Sample = new HitSampleInfo {
+                Type = (SampleType)Math.Max(1, int.Parse(split[4])),
+                Set = SampleSet.Soft,
+            };
             result.NewCombo = combo;
             // TODO: "addition" field
             return result;

osu.Game/Modes/Objects/Drawables/DrawableHitObject.cs

@@ -5,7 +5,11 @@ using System;
 using System.ComponentModel;
 using System.Diagnostics;
 using osu.Framework;
+using osu.Framework.Allocation;
+using osu.Framework.Audio;
+using osu.Framework.Audio.Sample;
 using osu.Framework.Graphics.Containers;
+using osu.Game.Beatmaps.Samples;
 using OpenTK;
 using Container = osu.Framework.Graphics.Containers.Container;
 
@@ -40,9 +44,25 @@ namespace osu.Game.Modes.Objects.Drawables
                 state = value;
 
                 UpdateState(state);
+
+                if (State == ArmedState.Hit)
+                    PlaySample();
             }
         }
 
+        AudioSample sample;
+
+        [BackgroundDependencyLoader]
+        private void load(AudioManager audio)
+        {
+            sample = audio.Sample.Get($@"Gameplay/{(HitObject.Sample.Set).ToString().ToLower()}-hit{HitObject.Sample.Type.ToString().ToLower()}");
+        }
+
+        protected void PlaySample()
+        {
+            sample?.Play();
+        }
+
         protected override void LoadComplete()
         {
             base.LoadComplete();