Implement bottom stage image

osu.Game.Rulesets.Mania.Tests/Skinning/TestSceneStageForeground.cs

@@ -0,0 +1,33 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using osu.Framework.Allocation;
+using osu.Framework.Graphics;
+using osu.Game.Rulesets.Mania.Skinning;
+using osu.Game.Skinning;
+
+namespace osu.Game.Rulesets.Mania.Tests.Skinning
+{
+    public class TestSceneStageForeground : ManiaSkinnableTestScene
+    {
+        public override IReadOnlyList<Type> RequiredTypes => base.RequiredTypes.Concat(new[]
+        {
+            typeof(LegacyStageForeground),
+        }).ToList();
+
+        [BackgroundDependencyLoader]
+        private void load()
+        {
+            SetContents(() => new SkinnableDrawable(new ManiaSkinComponent(ManiaSkinComponents.StageForeground), _ => null)
+            {
+                Anchor = Anchor.Centre,
+                Origin = Anchor.Centre,
+                RelativeSizeAxes = Axes.Both,
+                Width = 0.5f,
+            });
+        }
+    }
+}

osu.Game.Rulesets.Mania/ManiaSkinComponent.cs

@@ -40,6 +40,7 @@ namespace osu.Game.Rulesets.Mania
         HoldNoteTail,
         HoldNoteBody,
         HitExplosion,
-        StageBackground
+        StageBackground,
+        StageForeground,
     }
 }

osu.Game.Rulesets.Mania/Skinning/LegacyStageForeground.cs

@@ -0,0 +1,56 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Framework.Allocation;
+using osu.Framework.Bindables;
+using osu.Framework.Graphics;
+using osu.Game.Rulesets.UI.Scrolling;
+using osu.Game.Skinning;
+using osuTK;
+
+namespace osu.Game.Rulesets.Mania.Skinning
+{
+    public class LegacyStageForeground : LegacyManiaElement
+    {
+        private readonly IBindable<ScrollingDirection> direction = new Bindable<ScrollingDirection>();
+
+        private Drawable sprite;
+
+        public LegacyStageForeground()
+        {
+            RelativeSizeAxes = Axes.Both;
+        }
+
+        [BackgroundDependencyLoader]
+        private void load(ISkinSource skin, IScrollingInfo scrollingInfo)
+        {
+            string bottomImage = GetManiaSkinConfig<string>(skin, LegacyManiaSkinConfigurationLookups.BottomStageImage)?.Value
+                                 ?? "mania-stage-bottom";
+
+            sprite = skin.GetAnimation(bottomImage, true, true)?.With(d =>
+            {
+                if (d == null)
+                    return;
+
+                d.Scale = new Vector2(1.6f);
+            });
+
+            if (sprite != null)
+                InternalChild = sprite;
+
+            direction.BindTo(scrollingInfo.Direction);
+            direction.BindValueChanged(onDirectionChanged, true);
+        }
+
+        private void onDirectionChanged(ValueChangedEvent<ScrollingDirection> direction)
+        {
+            if (sprite == null)
+                return;
+
+            if (direction.NewValue == ScrollingDirection.Up)
+                sprite.Anchor = sprite.Origin = Anchor.TopCentre;
+            else
+                sprite.Anchor = sprite.Origin = Anchor.BottomCentre;
+        }
+    }
+}

osu.Game.Rulesets.Mania/Skinning/ManiaLegacySkinTransformer.cs

@@ -84,6 +84,9 @@ namespace osu.Game.Rulesets.Mania.Skinning
 
                         case ManiaSkinComponents.StageBackground:
                             return new LegacyStageBackground();
+
+                        case ManiaSkinComponents.StageForeground:
+                            return new LegacyStageForeground();
                     }
 
                     break;

osu.Game.Rulesets.Mania/UI/Stage.cs

@@ -100,6 +100,10 @@ namespace osu.Game.Rulesets.Mania.UI
                                 RelativeSizeAxes = Axes.Y,
                             }
                         },
+                        new SkinnableDrawable(new ManiaSkinComponent(ManiaSkinComponents.StageForeground), _ => null)
+                        {
+                            RelativeSizeAxes = Axes.Both
+                        },
                         judgements = new JudgementContainer<DrawableManiaJudgement>
                         {
                             Anchor = Anchor.TopCentre,

osu.Game/Skinning/LegacyManiaSkinConfigurationLookup.cs

@@ -43,5 +43,6 @@ namespace osu.Game.Skinning
         MinimumColumnWidth,
         LeftStageImage,
         RightStageImage,
+        BottomStageImage
     }
 }