Merge pull request #1329 from huoyaoyuan/spm-counter

Implement SPM counter on osu! spinners

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

@@ -22,6 +22,7 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
 
         private readonly SpinnerDisc disc;
         private readonly SpinnerTicks ticks;
+        private readonly SpinnerSpmCounter spmCounter;
 
         private readonly Container mainContainer;
 
@@ -103,6 +104,13 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
                         },
                     }
                 },
+                spmCounter = new SpinnerSpmCounter
+                {
+                    Anchor = Anchor.Centre,
+                    Origin = Anchor.Centre,
+                    Y = 120,
+                    Alpha = 0
+                }
             };
         }
 
@@ -157,6 +165,8 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
         protected override void Update()
         {
             disc.Tracking = OsuActionInputManager.PressedActions.Any(x => x == OsuAction.LeftButton || x == OsuAction.RightButton);
+            if (!spmCounter.IsPresent && disc.Tracking)
+                spmCounter.FadeIn(TIME_FADEIN);
 
             base.Update();
         }
@@ -167,6 +177,7 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
 
             circle.Rotation = disc.Rotation;
             ticks.Rotation = disc.Rotation;
+            spmCounter.SetRotation(disc.RotationAbsolute);
 
             float relativeCircleScale = spinner.Scale * circle.DrawHeight / mainContainer.DrawHeight;
             disc.ScaleTo(relativeCircleScale + (1 - relativeCircleScale) * Progress, 200, Easing.OutQuint);

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

@@ -77,7 +77,6 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables.Pieces
         private float lastAngle;
         private float currentRotation;
         public float RotationAbsolute;
-
         private int completeTick;
 
         private bool updateCompleteTick() => completeTick != (completeTick = (int)(RotationAbsolute / 360));

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

@@ -0,0 +1,75 @@
+// 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.Collections.Generic;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers;
+using osu.Game.Graphics.Sprites;
+
+namespace osu.Game.Rulesets.Osu.Objects.Drawables.Pieces
+{
+    public class SpinnerSpmCounter : Container
+    {
+        private readonly OsuSpriteText spmText;
+
+        public SpinnerSpmCounter()
+        {
+            Children = new Drawable[]
+            {
+                spmText = new OsuSpriteText
+                {
+                    Anchor = Anchor.TopCentre,
+                    Origin = Anchor.TopCentre,
+                    Text = @"0",
+                    Font = @"Venera",
+                    TextSize = 24
+                },
+                new OsuSpriteText
+                {
+                    Anchor = Anchor.TopCentre,
+                    Origin = Anchor.TopCentre,
+                    Text = @"SPINS PER MINUTE",
+                    Font = @"Venera",
+                    TextSize = 12,
+                    Y = 30
+                }
+            };
+        }
+
+        private double spm;
+
+        public double SpinsPerMinute
+        {
+            get { return spm; }
+            private set
+            {
+                if (value == spm) return;
+                spm = value;
+                spmText.Text = Math.Truncate(value).ToString(@"#0");
+            }
+        }
+
+        private struct RotationRecord
+        {
+            public float Rotation;
+            public double Time;
+        }
+
+        private readonly Queue<RotationRecord> records = new Queue<RotationRecord>();
+        private const double spm_count_duration = 595; // not using hundreds to avoid frame rounding issues
+
+        public void SetRotation(float currentRotation)
+        {
+            if (records.Count > 0)
+            {
+                var record = records.Peek();
+                while (Time.Current - records.Peek().Time > spm_count_duration)
+                    record = records.Dequeue();
+                SpinsPerMinute = (currentRotation - record.Rotation) / (Time.Current - record.Time) * 1000 * 60 / 360;
+            }
+
+            records.Enqueue(new RotationRecord { Rotation = currentRotation, Time = Time.Current });
+        }
+    }
+}

osu.Game.Rulesets.Osu/osu.Game.Rulesets.Osu.csproj

@@ -68,6 +68,7 @@
     <Compile Include="Objects\Drawables\Pieces\RingPiece.cs" />
     <Compile Include="Objects\Drawables\Pieces\SliderBouncer.cs" />
     <Compile Include="Objects\Drawables\Pieces\SpinnerDisc.cs" />
+    <Compile Include="Objects\Drawables\Pieces\SpinnerSpmCounter.cs" />
     <Compile Include="Objects\Drawables\Pieces\SpinnerTicks.cs" />
     <Compile Include="Objects\Drawables\Pieces\TrianglesPiece.cs" />
     <Compile Include="Objects\Drawables\Pieces\SliderBall.cs" />