From 4f9c3fde07a662ef43925aadb4cd562c2afed1ac Mon Sep 17 00:00:00 2001
From: Dean Herbert <pe@ppy.sh>
Date: Wed, 1 Sep 2021 15:10:56 +0900
Subject: [PATCH] Move alpha adjustment back to `LegacySliderBody` to correctly
 handle default legacy skin

---
 .../Skinning/Default/PlaySliderBody.cs        |  6 +++---
 .../Skinning/Legacy/LegacySliderBody.cs       |  7 +++++++
 .../Legacy/OsuLegacySkinTransformer.cs        | 21 ++-----------------
 3 files changed, 12 insertions(+), 22 deletions(-)

diff --git a/osu.Game.Rulesets.Osu/Skinning/Default/PlaySliderBody.cs b/osu.Game.Rulesets.Osu/Skinning/Default/PlaySliderBody.cs
index 4dd7b2d69c..8602ebc88b 100644
--- a/osu.Game.Rulesets.Osu/Skinning/Default/PlaySliderBody.cs
+++ b/osu.Game.Rulesets.Osu/Skinning/Default/PlaySliderBody.cs
@@ -35,7 +35,7 @@ namespace osu.Game.Rulesets.Osu.Skinning.Default
             pathVersion.BindValueChanged(_ => Refresh());
 
             accentColour = drawableObject.AccentColour.GetBoundCopy();
-            accentColour.BindValueChanged(accent => updateAccentColour(skin, accent.NewValue), true);
+            accentColour.BindValueChanged(accent => AccentColour = GetBodyAccentColour(skin, accent.NewValue), true);
 
             config?.BindWith(OsuRulesetSetting.SnakingInSliders, SnakingIn);
             config?.BindWith(OsuRulesetSetting.SnakingOutSliders, configSnakingOut);
@@ -62,7 +62,7 @@ namespace osu.Game.Rulesets.Osu.Skinning.Default
             }
         }
 
-        private void updateAccentColour(ISkinSource skin, Color4 defaultAccentColour)
-            => AccentColour = skin.GetConfig<OsuSkinColour, Color4>(OsuSkinColour.SliderTrackOverride)?.Value ?? defaultAccentColour;
+        protected virtual Color4 GetBodyAccentColour(ISkinSource skin, Color4 hitObjectAccentColour) =>
+            skin.GetConfig<OsuSkinColour, Color4>(OsuSkinColour.SliderTrackOverride)?.Value ?? hitObjectAccentColour;
     }
 }
diff --git a/osu.Game.Rulesets.Osu/Skinning/Legacy/LegacySliderBody.cs b/osu.Game.Rulesets.Osu/Skinning/Legacy/LegacySliderBody.cs
index 7d69e5ecdc..29a0745193 100644
--- a/osu.Game.Rulesets.Osu/Skinning/Legacy/LegacySliderBody.cs
+++ b/osu.Game.Rulesets.Osu/Skinning/Legacy/LegacySliderBody.cs
@@ -5,6 +5,7 @@ using System;
 using osu.Framework.Extensions.Color4Extensions;
 using osu.Game.Rulesets.Osu.Objects;
 using osu.Game.Rulesets.Osu.Skinning.Default;
+using osu.Game.Skinning;
 using osu.Game.Utils;
 using osuTK.Graphics;
 
@@ -14,6 +15,12 @@ namespace osu.Game.Rulesets.Osu.Skinning.Legacy
     {
         protected override DrawableSliderPath CreateSliderPath() => new LegacyDrawableSliderPath();
 
+        protected override Color4 GetBodyAccentColour(ISkinSource skin, Color4 hitObjectAccentColour)
+        {
+            // legacy skins use a constant value for slider track alpha, regardless of the source colour.
+            return base.GetBodyAccentColour(skin, hitObjectAccentColour).Opacity(0.7f);
+        }
+
         private class LegacyDrawableSliderPath : DrawableSliderPath
         {
             private const float shadow_portion = 1 - (OsuLegacySkinTransformer.LEGACY_CIRCLE_RADIUS / OsuHitObject.OBJECT_RADIUS);
diff --git a/osu.Game.Rulesets.Osu/Skinning/Legacy/OsuLegacySkinTransformer.cs b/osu.Game.Rulesets.Osu/Skinning/Legacy/OsuLegacySkinTransformer.cs
index 16c770706d..41b0a88f11 100644
--- a/osu.Game.Rulesets.Osu/Skinning/Legacy/OsuLegacySkinTransformer.cs
+++ b/osu.Game.Rulesets.Osu/Skinning/Legacy/OsuLegacySkinTransformer.cs
@@ -3,11 +3,9 @@
 
 using System;
 using osu.Framework.Bindables;
-using osu.Framework.Extensions.Color4Extensions;
 using osu.Framework.Graphics;
 using osu.Game.Skinning;
 using osuTK;
-using osuTK.Graphics;
 
 namespace osu.Game.Rulesets.Osu.Skinning.Legacy
 {
@@ -120,23 +118,8 @@ namespace osu.Game.Rulesets.Osu.Skinning.Legacy
         {
             switch (lookup)
             {
-                case OsuSkinColour colourLookup:
-                    var colour = base.GetConfig<SkinCustomColourLookup, TValue>(new SkinCustomColourLookup(colourLookup));
-
-                    if (colour == null)
-                        return null;
-
-                    switch (colourLookup)
-                    {
-                        case OsuSkinColour.SliderTrackOverride:
-                            var bindableColour = ((Bindable<Color4>)colour);
-
-                            // legacy skins use a constant value for slider track alpha, regardless of the source colour.
-                            bindableColour.Value = bindableColour.Value.Opacity(0.7f);
-                            break;
-                    }
-
-                    return colour;
+                case OsuSkinColour colour:
+                    return base.GetConfig<SkinCustomColourLookup, TValue>(new SkinCustomColourLookup(colour));
 
                 case OsuSkinConfiguration osuLookup:
                     switch (osuLookup)