Add deterministic disposal for textures in IResourceCache (#6483)

* Add deterministic disposal for textures in IResourceCache

* Review

* Thanks PJB

Co-authored-by: Pieter-Jan Briers <pieterjan.briers@gmail.com>

* Review

---------

Co-authored-by: Pieter-Jan Briers <pieterjan.briers@gmail.com>

Robust.Client/ResourceManagement/IBaseResource.cs

@@ -0,0 +1,12 @@
+namespace Robust.Client.ResourceManagement;
+
+/// <summary>
+/// Defines type-level metadata for resource types.
+/// </summary>
+public interface IBaseResource
+{
+    /// <summary>
+    /// Whether resources of this type can be deterministically removed from the cache.
+    /// </summary>
+    static virtual bool CanBeRemoved => false;
+}

Robust.Client/ResourceManagement/IResourceCache.cs

@@ -28,6 +28,10 @@ public interface IResourceCache : IResourceManager
 
     bool TryGetResource(AudioStream stream, [NotNullWhen(true)] out AudioResource? resource);
 
+    bool TryRemoveResource<T>(string path) where T : BaseResource, IBaseResource, new();
+
+    bool TryRemoveResource<T>(ResPath path) where T : BaseResource, IBaseResource, new();
+
     void ReloadResource<T>(string path)
         where T : BaseResource, new();
 

Robust.Client/ResourceManagement/ResourceCache.cs

@@ -7,7 +7,6 @@ using System.Runtime.CompilerServices;
 using Robust.Client.Audio;
 using Robust.Shared.ContentPack;
 using Robust.Shared.IoC;
-using Robust.Shared.Log;
 using Robust.Shared.Utility;
 
 namespace Robust.Client.ResourceManagement;
@@ -107,6 +106,28 @@ internal sealed partial class ResourceCache : ResourceManager, IResourceCacheInt
         return true;
     }
 
+    public bool TryRemoveResource<T>(string path) where T : BaseResource, IBaseResource, new()
+        => TryRemoveResource<T>(new ResPath(path));
+
+    public bool TryRemoveResource<T>(ResPath path) where T : BaseResource, IBaseResource, new()
+    {
+        if (!T.CanBeRemoved)
+            throw new NotSupportedException($"Resource type '{typeof(T)}' does not support deterministic removal.");
+
+        if (new T().Fallback == path)
+            return false;
+
+        var cache = GetTypeData<T>();
+
+        if (!cache.Resources.Remove(path, out var resource))
+            return false;
+
+        cache.NonExistent.Remove(path);
+        resource.Dispose();
+
+        return true;
+    }
+
     public void ReloadResource<T>(string path) where T : BaseResource, new()
     {
         ReloadResource<T>(new ResPath(path));

Robust.Client/ResourceManagement/ResourceTypes/TextureResource.cs

@@ -1,4 +1,5 @@
-using System.IO;
+using System;
+using System.IO;
 using System.Threading;
 using Robust.Client.Graphics;
 using Robust.Shared.ContentPack;
@@ -13,12 +14,22 @@ using YamlDotNet.RepresentationModel;
 
 namespace Robust.Client.ResourceManagement
 {
-    public sealed class TextureResource : BaseResource
+    public sealed class TextureResource : BaseResource, IBaseResource
     {
         private OwnedTexture _texture = default!;
-        public override ResPath? Fallback => new("/Textures/noSprite.png");
+        private bool _disposed;
 
-        public Texture Texture => _texture;
+        public override ResPath? Fallback => new("/Textures/noSprite.png");
+        static bool IBaseResource.CanBeRemoved => true;
+
+        public Texture Texture
+        {
+            get
+            {
+                ObjectDisposedException.ThrowIf(_disposed, this);
+                return _texture;
+            }
+        }
 
         public override void Load(IDependencyCollection dependencies, ResPath path)
         {
@@ -106,12 +117,14 @@ namespace Robust.Client.ResourceManagement
 
         public override void Reload(IDependencyCollection dependencies, ResPath path, CancellationToken ct = default)
         {
+            ObjectDisposedException.ThrowIf(_disposed, this);
+
             var data = new LoadStepData {Path = path};
 
             LoadTextureParameters(dependencies.Resolve<IResourceManager>(), data);
             LoadPreTextureData(dependencies.Resolve<IResourceManager>(), data);
 
-            if (data.Image.Width == Texture.Width && data.Image.Height == Texture.Height)
+            if (data.Image.Width == _texture.Width && data.Image.Height == _texture.Height)
             {
                 // Dimensions match, rewrite texture in place.
                 _texture.SetSubImage(Vector2i.Zero, data.Image);
@@ -127,6 +140,15 @@ namespace Robust.Client.ResourceManagement
             data.Image.Dispose();
         }
 
+        public override void Dispose()
+        {
+            if (_disposed) return;
+            _disposed = true;
+            _texture?.Dispose();
+
+            base.Dispose();
+        }
+
         internal sealed class LoadStepData
         {
             public ResPath Path = default!;