Merge pull request #812 from ColdVolcano/menu-flashes

Menu flashes

osu.Game/Screens/Menu/MainMenu.cs

@@ -48,7 +48,8 @@ namespace osu.Game.Screens.Menu
                             OnSolo = delegate { Push(consumeSongSelect()); },
                             OnMulti = delegate { Push(new Lobby()); },
                             OnExit = delegate { Exit(); },
-                        }
+                        },
+                        new MenuSideFlashes(),
                     }
                 }
             };

osu.Game/Screens/Menu/MenuSideFlashes.cs

@@ -0,0 +1,96 @@
+// Copyright (c) 2007-2017 ppy Pty Ltd <contact@ppy.sh>.
+// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
+
+using OpenTK.Graphics;
+using osu.Framework.Allocation;
+using osu.Framework.Audio.Track;
+using osu.Framework.Configuration;
+using osu.Framework.Extensions.Color4Extensions;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Colour;
+using osu.Framework.Graphics.Sprites;
+using osu.Game.Beatmaps;
+using osu.Game.Beatmaps.ControlPoints;
+using osu.Game.Graphics;
+using osu.Game.Graphics.Containers;
+using System;
+
+namespace osu.Game.Screens.Menu
+{
+    public class MenuSideFlashes : BeatSyncedContainer
+    {
+        public override bool HandleInput => false;
+
+        private readonly Bindable<WorkingBeatmap> beatmap = new Bindable<WorkingBeatmap>();
+
+        private readonly Box leftBox;
+        private readonly Box rightBox;
+
+        private const float amplitude_dead_zone = 0.25f;
+        private const float alpha_multiplier = (1 - amplitude_dead_zone) / 0.55f;
+        private const float kiai_multiplier = (1 - amplitude_dead_zone * 0.95f) / 0.8f;
+
+        private const int box_max_alpha = 200;
+        private const double box_fade_in_time = 65;
+        private const int box_width = 200;
+
+        public MenuSideFlashes()
+        {
+            RelativeSizeAxes = Axes.Both;
+            Anchor = Anchor.Centre;
+            Origin = Anchor.Centre;
+            Children = new Drawable[]
+            {
+                leftBox = new Box
+                {
+                    Anchor = Anchor.CentreLeft,
+                    Origin = Anchor.CentreLeft,
+                    RelativeSizeAxes = Axes.Y,
+                    Width = box_width,
+                    Alpha = 0,
+                    BlendingMode = BlendingMode.Additive,
+                },
+                rightBox = new Box
+                {
+                    Anchor = Anchor.CentreRight,
+                    Origin = Anchor.CentreRight,
+                    RelativeSizeAxes = Axes.Y,
+                    Width = box_width,
+                    Alpha = 0,
+                    BlendingMode = BlendingMode.Additive,
+                }
+            };
+        }
+
+        [BackgroundDependencyLoader]
+        private void load(OsuGameBase game, OsuColour colours)
+        {
+            beatmap.BindTo(game.Beatmap);
+
+            // linear colour looks better in this case, so let's use it for now.
+            Color4 gradientDark = colours.Blue.Opacity(0).ToLinear();
+            Color4 gradientLight = colours.Blue.Opacity(0.3f).ToLinear();
+
+            leftBox.ColourInfo = ColourInfo.GradientHorizontal(gradientLight, gradientDark);
+            rightBox.ColourInfo = ColourInfo.GradientHorizontal(gradientDark, gradientLight);
+        }
+
+        protected override void OnNewBeat(int beatIndex, TimingControlPoint timingPoint, EffectControlPoint effectPoint, TrackAmplitudes amplitudes)
+        {
+            if (beatIndex < 0)
+                return;
+
+            if (effectPoint.KiaiMode ? beatIndex % 2 == 0 : beatIndex % (int)timingPoint.TimeSignature == 0)
+                flash(leftBox, timingPoint.BeatLength, effectPoint.KiaiMode, amplitudes);
+            if (effectPoint.KiaiMode ? beatIndex % 2 == 1 : beatIndex % (int)timingPoint.TimeSignature == 0)
+                flash(rightBox, timingPoint.BeatLength, effectPoint.KiaiMode, amplitudes);
+        }
+
+        private void flash(Drawable d, double beatLength, bool kiai, TrackAmplitudes amplitudes)
+        {
+            d.FadeTo(Math.Max(0, ((d.Equals(leftBox) ? amplitudes.LeftChannel : amplitudes.RightChannel) - amplitude_dead_zone) / (kiai ? kiai_multiplier : alpha_multiplier)), box_fade_in_time);
+            using (d.BeginDelayedSequence(box_fade_in_time))
+                d.FadeOut(beatLength, EasingTypes.In);
+        }
+    }
+}

osu.Game/osu.Game.csproj

@@ -189,6 +189,7 @@
     <Compile Include="Database\RulesetDatabase.cs" />
     <Compile Include="Rulesets\Scoring\Score.cs" />
     <Compile Include="Rulesets\Scoring\ScoreProcessor.cs" />
+    <Compile Include="Screens\Menu\MenuSideFlashes.cs" />
     <Compile Include="Screens\Play\HUD\HealthDisplay.cs" />
     <Compile Include="Screens\Play\HUDOverlay.cs" />
     <Compile Include="Screens\Play\HUD\StandardHealthDisplay.cs" />