EXPERIMENTAL: Metal backend (#441)

This is not a continuation of the Metal backend; this is simply bringing
the branch up to date and merging it as-is behind an experiment.

---------

Co-authored-by: Isaac Marovitz <isaacryu@icloud.com>
Co-authored-by: Samuliak <samuliak77@gmail.com>
Co-authored-by: SamoZ256 <96914946+SamoZ256@users.noreply.github.com>
Co-authored-by: Isaac Marovitz <42140194+IsaacMarovitz@users.noreply.github.com>
Co-authored-by: riperiperi <rhy3756547@hotmail.com>
Co-authored-by: Gabriel A <gab.dark.100@gmail.com>

src/Ryujinx.Graphics.Metal/ImageArray.cs

@@ -0,0 +1,74 @@
+using Ryujinx.Graphics.GAL;
+using System.Runtime.Versioning;
+
+namespace Ryujinx.Graphics.Metal
+{
+    [SupportedOSPlatform("macos")]
+    internal class ImageArray : IImageArray
+    {
+        private readonly TextureRef[] _textureRefs;
+        private readonly TextureBuffer[] _bufferTextureRefs;
+
+        private readonly bool _isBuffer;
+        private readonly Pipeline _pipeline;
+
+        public ImageArray(int size, bool isBuffer, Pipeline pipeline)
+        {
+            if (isBuffer)
+            {
+                _bufferTextureRefs = new TextureBuffer[size];
+            }
+            else
+            {
+                _textureRefs = new TextureRef[size];
+            }
+
+            _isBuffer = isBuffer;
+            _pipeline = pipeline;
+        }
+
+        public void SetImages(int index, ITexture[] images)
+        {
+            for (int i = 0; i < images.Length; i++)
+            {
+                ITexture image = images[i];
+
+                if (image is TextureBuffer textureBuffer)
+                {
+                    _bufferTextureRefs[index + i] = textureBuffer;
+                }
+                else if (image is Texture texture)
+                {
+                    _textureRefs[index + i].Storage = texture;
+                }
+                else if (!_isBuffer)
+                {
+                    _textureRefs[index + i].Storage = null;
+                }
+                else
+                {
+                    _bufferTextureRefs[index + i] = null;
+                }
+            }
+
+            SetDirty();
+        }
+
+        public TextureRef[] GetTextureRefs()
+        {
+            return _textureRefs;
+        }
+
+        public TextureBuffer[] GetBufferTextureRefs()
+        {
+            return _bufferTextureRefs;
+        }
+
+        private void SetDirty()
+        {
+            _pipeline.DirtyImages();
+        }
+
+        public void Dispose() { }
+    }
+}