Create ZoomIn Mod

osu.Game.Rulesets.Osu/Mods/OsuModZoomIn.cs

@@ -0,0 +1,55 @@
+// Copyright (c) 2007-2018 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.Framework.Graphics;
+using osu.Game.Graphics;
+using osu.Game.Rulesets.Mods;
+using osu.Game.Rulesets.Objects.Drawables;
+using osu.Game.Rulesets.Osu.Objects;
+using osu.Game.Rulesets.Osu.Objects.Drawables;
+using OpenTK;
+
+namespace osu.Game.Rulesets.Osu.Mods
+{
+    public class OsuModZoomIn : Mod, IApplicableToDrawableHitObjects
+    {
+        public override string Name => "Zoom In";
+        public override string ShortenedName => "ZI";
+        public override FontAwesome Icon => FontAwesome.fa_dot_circle_o;
+        public override ModType Type => ModType.Fun;
+        public override string Description => "Circles zoom in. No approach circles.";
+        public override double ScoreMultiplier => 1;
+
+        public void ApplyToDrawableHitObjects(IEnumerable<DrawableHitObject> drawables)
+        {
+            foreach (var drawable in drawables)
+            {
+                drawable.ApplyCustomUpdateState += ApplyBounceState;
+            }
+        }
+
+        protected void ApplyBounceState(DrawableHitObject drawable, ArmedState state)
+        {
+            if (!(drawable is DrawableOsuHitObject d))
+                return;
+
+            var h = (OsuHitObject)drawable.HitObject;
+
+            double appearTime = h.StartTime - h.TimePreempt;
+            double moveDuration = h.TimePreempt;
+
+            using (drawable.BeginAbsoluteSequence(appearTime, true))
+            {
+                var origScale = drawable.Scale;
+
+                drawable
+                    .ScaleTo(0.0f)
+                    .ScaleTo(origScale, moveDuration, Easing.InOutSine);
+            }
+
+            // Hide approach circle
+            (drawable as DrawableHitCircle)?.ApproachCircle.Hide();
+        }
+    }
+}

osu.Game.Rulesets.Osu/OsuRuleset.cs

@@ -121,6 +121,7 @@ namespace osu.Game.Rulesets.Osu
                     return new Mod[] {
                         new OsuModTransform(),
                         new OsuModWiggle(),
+                        new OsuModZoomIn(),
                     };
                 default:
                     return new Mod[] { };