Setup basics to allow extracting serializable content from skinnable Drawables

osu.Game/Extensions/DrawableExtensions.cs

@@ -5,6 +5,7 @@ using System;
 using osu.Framework.Graphics;
 using osu.Framework.Input.Bindings;
 using osu.Framework.Threading;
+using osu.Game.Screens.Play.HUD;
 using osuTK;
 
 namespace osu.Game.Extensions
@@ -43,5 +44,7 @@ namespace osu.Game.Extensions
         /// <returns>The delta vector in Parent's coordinates.</returns>
         public static Vector2 ScreenSpaceDeltaToParentSpace(this Drawable drawable, Vector2 delta) =>
             drawable.Parent.ToLocalSpace(drawable.Parent.ToScreenSpace(Vector2.Zero) + delta);
+
+        public static StoredSkinnableInfo CreateSerialisedInformation(this Drawable component) => new StoredSkinnableInfo(component);
     }
 }

osu.Game/Screens/Play/HUD/ISkinnableInfo.cs

@@ -0,0 +1,32 @@
+// 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 osu.Framework.Graphics;
+using osu.Game.IO.Serialization;
+using osuTK;
+
+namespace osu.Game.Screens.Play.HUD
+{
+    public interface ISkinnableInfo : IJsonSerializable
+    {
+        public Type Type { get; set; }
+
+        public Type Target { get; set; }
+
+        public Vector2 Position { get; set; }
+
+        public float Rotation { get; set; }
+
+        public Vector2 Scale { get; set; }
+
+        public Anchor Anchor { get; set; }
+    }
+
+    /// <summary>
+    /// A container which supports skinnable components being added to it.
+    /// </summary>
+    public interface ISkinnableTarget
+    {
+    }
+}

osu.Game/Screens/Play/HUD/SkinnableElementTargetContainer.cs

@@ -0,0 +1,11 @@
+// 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.Graphics.Containers;
+
+namespace osu.Game.Screens.Play.HUD
+{
+    public class SkinnableElementTargetContainer : Container, ISkinnableTarget
+    {
+    }
+}

osu.Game/Screens/Play/HUD/StoredSkinnableInfo.cs

@@ -0,0 +1,43 @@
+// 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 osu.Framework.Graphics;
+using osuTK;
+
+namespace osu.Game.Screens.Play.HUD
+{
+    /// <summary>
+    /// Serialised information governing custom changes to an <see cref="ISkinnableComponent"/>.
+    /// </summary>
+    public class StoredSkinnableInfo : ISkinnableInfo
+    {
+        public StoredSkinnableInfo(Drawable component)
+        {
+            Type = component.GetType();
+
+            var target = component.Parent as ISkinnableTarget
+                         // todo: this is temporary until we serialise the default layouts out of SkinnableDrawables.
+                         ?? component.Parent?.Parent as ISkinnableTarget;
+
+            Target = target?.GetType();
+
+            Position = component.Position;
+            Rotation = component.Rotation;
+            Scale = component.Scale;
+            Anchor = component.Anchor;
+        }
+
+        public Type Type { get; set; }
+
+        public Type Target { get; set; }
+
+        public Vector2 Position { get; set; }
+
+        public float Rotation { get; set; }
+
+        public Vector2 Scale { get; set; }
+
+        public Anchor Anchor { get; set; }
+    }
+}

osu.Game/Screens/Play/HUDOverlay.cs

@@ -91,16 +91,16 @@ namespace osu.Game.Screens.Play
                         {
                             new Drawable[]
                             {
-                                new Container
+                                new MainHUDElements
                                 {
                                     RelativeSizeAxes = Axes.Both,
                                     Children = new Drawable[]
                                     {
-                                        HealthDisplay = CreateHealthDisplay(),
-                                        AccuracyCounter = CreateAccuracyCounter(),
-                                        ScoreCounter = CreateScoreCounter(),
-                                        CreateComboCounter(),
-                                        CreateHitErrorDisplayOverlay(),
+                                        HealthDisplay = new SkinnableHealthDisplay(),
+                                        AccuracyCounter = new SkinnableAccuracyCounter(),
+                                        ScoreCounter = new SkinnableScoreCounter(),
+                                        new SkinnableComboCounter(),
+                                        new HitErrorDisplay(this.drawableRuleset?.FirstAvailableHitWindows),
                                     }
                                 },
                             },
@@ -263,48 +263,38 @@ namespace osu.Game.Screens.Play
             Progress.BindDrawableRuleset(drawableRuleset);
         }
 
-        protected SkinnableAccuracyCounter CreateAccuracyCounter() => new SkinnableAccuracyCounter();
-
-        protected SkinnableScoreCounter CreateScoreCounter() => new SkinnableScoreCounter();
-
-        protected SkinnableComboCounter CreateComboCounter() => new SkinnableComboCounter();
-
-        protected SkinnableHealthDisplay CreateHealthDisplay() => new SkinnableHealthDisplay();
-
-        protected virtual FailingLayer CreateFailingLayer() => new FailingLayer
+        protected FailingLayer CreateFailingLayer() => new FailingLayer
         {
             ShowHealth = { BindTarget = ShowHealthbar }
         };
 
-        protected virtual KeyCounterDisplay CreateKeyCounter() => new KeyCounterDisplay
+        protected KeyCounterDisplay CreateKeyCounter() => new KeyCounterDisplay
         {
             Anchor = Anchor.BottomRight,
             Origin = Anchor.BottomRight,
         };
 
-        protected virtual SongProgress CreateProgress() => new SongProgress
+        protected SongProgress CreateProgress() => new SongProgress
         {
             Anchor = Anchor.BottomLeft,
             Origin = Anchor.BottomLeft,
             RelativeSizeAxes = Axes.X,
         };
 
-        protected virtual HoldForMenuButton CreateHoldForMenuButton() => new HoldForMenuButton
+        protected HoldForMenuButton CreateHoldForMenuButton() => new HoldForMenuButton
         {
             Anchor = Anchor.BottomRight,
             Origin = Anchor.BottomRight,
         };
 
-        protected virtual ModDisplay CreateModsContainer() => new ModDisplay
+        protected ModDisplay CreateModsContainer() => new ModDisplay
         {
             Anchor = Anchor.TopRight,
             Origin = Anchor.TopRight,
             AutoSizeAxes = Axes.Both,
         };
 
-        protected virtual HitErrorDisplay CreateHitErrorDisplayOverlay() => new HitErrorDisplay(drawableRuleset?.FirstAvailableHitWindows);
-
-        protected virtual PlayerSettingsOverlay CreatePlayerSettingsOverlay() => new PlayerSettingsOverlay();
+        protected PlayerSettingsOverlay CreatePlayerSettingsOverlay() => new PlayerSettingsOverlay();
 
         public bool OnPressed(GlobalAction action)
         {
@@ -347,5 +337,9 @@ namespace osu.Game.Screens.Play
                     break;
             }
         }
+
+        public class MainHUDElements : SkinnableElementTargetContainer
+        {
+        }
     }
 }

osu.Game/Skinning/Editor/SkinBlueprintContainer.cs

@@ -1,9 +1,12 @@
 // 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.IO;
 using System.Linq;
+using Newtonsoft.Json;
 using osu.Framework.Graphics;
 using osu.Framework.Testing;
+using osu.Game.Extensions;
 using osu.Game.Rulesets.Edit;
 using osu.Game.Screens.Edit.Compose.Components;
 
@@ -27,7 +30,15 @@ namespace osu.Game.Skinning.Editor
 
         private void checkForComponents()
         {
-            foreach (var c in target.ChildrenOfType<ISkinnableComponent>().ToArray()) AddBlueprintFor(c);
+            ISkinnableComponent[] skinnableComponents = target.ChildrenOfType<ISkinnableComponent>().ToArray();
+
+            // todo: the OfType() call can be removed with better IDrawable support.
+            string json = JsonConvert.SerializeObject(skinnableComponents.OfType<Drawable>().Select(d => d.CreateSerialisedInformation()), new JsonSerializerSettings { Formatting = Formatting.Indented });
+
+            File.WriteAllText("/Users/Dean/json-out.json", json);
+
+            foreach (var c in skinnableComponents)
+                AddBlueprintFor(c);
 
             // We'd hope to eventually be running this in a more sensible way, but this handles situations where new drawables become present (ie. during ongoing gameplay)
             // or when drawables in the target are loaded asynchronously and may not be immediately available when this BlueprintContainer is loaded.

osu.Game/Skinning/ISkin.cs

@@ -57,5 +57,7 @@ namespace osu.Game.Skinning
         /// <returns>A matching value boxed in an <see cref="IBindable{TValue}"/>, or null if unavailable.</returns>
         [CanBeNull]
         IBindable<TValue> GetConfig<TLookup, TValue>(TLookup lookup);
+
+        // IEnumerable<ISkinnableInfo> ComponentInfo { get; }
     }
 }