Make structs readonly when applicable (#4002)

* Make all structs readonly when applicable. It should reduce amount of needless defensive copies

* Make structs with trivial boilerplate equality code record structs

* Remove unnecessary readonly modifiers from TextureCreateInfo

* Make BitMap structs readonly too

Ryujinx.Graphics.GAL/BlendDescriptor.cs

@@ -1,6 +1,6 @@
 namespace Ryujinx.Graphics.GAL
 {
-    public struct BlendDescriptor
+    public readonly struct BlendDescriptor
     {
         public bool Enable { get; }
 

Ryujinx.Graphics.GAL/BufferAssignment.cs

@@ -1,6 +1,6 @@
 namespace Ryujinx.Graphics.GAL
 {
-    public struct BufferAssignment
+    public readonly struct BufferAssignment
     {
         public readonly int Binding;
         public readonly BufferRange Range;

Ryujinx.Graphics.GAL/BufferHandle.cs

@@ -1,22 +1,14 @@
-using System;
-using System.Diagnostics.CodeAnalysis;
-using System.Runtime.InteropServices;
+using System.Runtime.InteropServices;
 
 namespace Ryujinx.Graphics.GAL
 {
     [StructLayout(LayoutKind.Sequential, Size = 8)]
-    public struct BufferHandle : IEquatable<BufferHandle>
+    public readonly record struct BufferHandle
     {
         private readonly ulong _value;
 
         public static BufferHandle Null => new BufferHandle(0);
 
         private BufferHandle(ulong value) => _value = value;
-
-        public override bool Equals(object obj) => obj is BufferHandle handle && Equals(handle);
-        public bool Equals([AllowNull] BufferHandle other) => other._value == _value;
-        public override int GetHashCode() => _value.GetHashCode();
-        public static bool operator ==(BufferHandle left, BufferHandle right) => left.Equals(right);
-        public static bool operator !=(BufferHandle left, BufferHandle right) => !(left == right);
     }
 }

Ryujinx.Graphics.GAL/BufferRange.cs

@@ -1,6 +1,6 @@
 namespace Ryujinx.Graphics.GAL
 {
-    public struct BufferRange
+    public readonly struct BufferRange
     {
         private static readonly BufferRange _empty = new BufferRange(BufferHandle.Null, 0, 0);
 

Ryujinx.Graphics.GAL/Capabilities.cs

@@ -2,7 +2,7 @@ using Ryujinx.Graphics.Shader.Translation;
 
 namespace Ryujinx.Graphics.GAL
 {
-    public struct Capabilities
+    public readonly struct Capabilities
     {
         public readonly TargetApi Api;
         public readonly string VendorName;

Ryujinx.Graphics.GAL/ColorF.cs

@@ -1,32 +1,4 @@
-using System;
-
 namespace Ryujinx.Graphics.GAL
 {
-    public struct ColorF : IEquatable<ColorF>
-    {
-        public float Red   { get; }
-        public float Green { get; }
-        public float Blue  { get; }
-        public float Alpha { get; }
-
-        public ColorF(float red, float green, float blue, float alpha)
-        {
-            Red   = red;
-            Green = green;
-            Blue  = blue;
-            Alpha = alpha;
-        }
-
-        public bool Equals(ColorF color) => Red   == color.Red &&
-                                            Green == color.Green &&
-                                            Blue  == color.Blue &&
-                                            Alpha == color.Alpha;
-
-        public override bool Equals(object obj) => (obj is ColorF color) && Equals(color);
-
-        public override int GetHashCode() => HashCode.Combine(Red, Green, Blue, Alpha);
-
-        public static bool operator ==(ColorF l, ColorF r) => l.Equals(r);
-        public static bool operator !=(ColorF l, ColorF r) => !l.Equals(r);
-    }
+    public readonly record struct ColorF(float Red, float Green, float Blue, float Alpha);
 }

Ryujinx.Graphics.GAL/DepthTestDescriptor.cs

@@ -1,6 +1,6 @@
 namespace Ryujinx.Graphics.GAL
 {
-    public struct DepthTestDescriptor
+    public readonly struct DepthTestDescriptor
     {
         public bool TestEnable  { get; }
         public bool WriteEnable { get; }

Ryujinx.Graphics.GAL/DeviceInfo.cs

@@ -1,6 +1,6 @@
 namespace Ryujinx.Graphics.GAL
 {
-    public struct DeviceInfo
+    public readonly struct DeviceInfo
     {
         public readonly string Id;
         public readonly string Vendor;

Ryujinx.Graphics.GAL/Extents2D.cs

@@ -2,7 +2,7 @@ using Ryujinx.Common;
 
 namespace Ryujinx.Graphics.GAL
 {
-    public struct Extents2D
+    public readonly struct Extents2D
     {
         public int X1 { get; }
         public int Y1 { get; }

Ryujinx.Graphics.GAL/Extents2DF.cs

@@ -1,6 +1,6 @@
 namespace Ryujinx.Graphics.GAL
 {
-    public struct Extents2DF
+    public readonly struct Extents2DF
     {
         public float X1 { get; }
         public float Y1 { get; }

Ryujinx.Graphics.GAL/HardwareInfo.cs

@@ -1,6 +1,6 @@
 namespace Ryujinx.Graphics.GAL
 {
-    public struct HardwareInfo
+    public readonly struct HardwareInfo
     {
         public string GpuVendor { get; }
         public string GpuModel { get; }

Ryujinx.Graphics.GAL/ImageCrop.cs

@@ -1,6 +1,6 @@
 namespace Ryujinx.Graphics.GAL
 {
-    public struct ImageCrop
+    public readonly struct ImageCrop
     {
         public int   Left         { get; }
         public int   Right        { get; }

Ryujinx.Graphics.GAL/MultisampleDescriptor.cs

@@ -1,6 +1,6 @@
 namespace Ryujinx.Graphics.GAL
 {
-    public struct MultisampleDescriptor
+    public readonly struct MultisampleDescriptor
     {
         public bool AlphaToCoverageEnable { get; }
         public bool AlphaToCoverageDitherEnable { get; }

Ryujinx.Graphics.GAL/ProgramPipelineState.cs

@@ -6,7 +6,7 @@ namespace Ryujinx.Graphics.GAL
     /// <summary>
     /// Descriptor for a pipeline buffer binding.
     /// </summary>
-    public struct BufferPipelineDescriptor
+    public readonly struct BufferPipelineDescriptor
     {
         public bool Enable { get; }
         public int Stride { get; }

Ryujinx.Graphics.GAL/Rectangle.cs

@@ -1,6 +1,6 @@
 namespace Ryujinx.Graphics.GAL
 {
-    public struct Rectangle<T> where T : unmanaged
+    public readonly struct Rectangle<T> where T : unmanaged
     {
         public T X { get; }
         public T Y { get; }

Ryujinx.Graphics.GAL/SamplerCreateInfo.cs

@@ -1,6 +1,6 @@
 namespace Ryujinx.Graphics.GAL
 {
-    public struct SamplerCreateInfo
+    public readonly struct SamplerCreateInfo
     {
         public MinFilter MinFilter { get; }
         public MagFilter MagFilter { get; }

Ryujinx.Graphics.GAL/ScreenCaptureImageInfo.cs

@@ -1,6 +1,6 @@
 namespace Ryujinx.Graphics.GAL
 {
-    public struct ScreenCaptureImageInfo
+    public readonly struct ScreenCaptureImageInfo
     {
         public ScreenCaptureImageInfo(int width, int height, bool isBgra, byte[] data, bool flipX, bool flipY)
         {

Ryujinx.Graphics.GAL/ShaderBindings.cs

@@ -2,7 +2,7 @@
 
 namespace Ryujinx.Graphics.GAL
 {
-    public struct ShaderBindings
+    public readonly struct ShaderBindings
     {
         public IReadOnlyCollection<int> UniformBufferBindings { get; }
         public IReadOnlyCollection<int> StorageBufferBindings { get; }

Ryujinx.Graphics.GAL/ShaderSource.cs

@@ -3,7 +3,7 @@ using Ryujinx.Graphics.Shader.Translation;
 
 namespace Ryujinx.Graphics.GAL
 {
-    public struct ShaderSource
+    public readonly struct ShaderSource
     {
         public string Code { get; }
         public byte[] BinaryCode { get; }

Ryujinx.Graphics.GAL/StencilTestDescriptor.cs

@@ -1,6 +1,6 @@
 namespace Ryujinx.Graphics.GAL
 {
-    public struct StencilTestDescriptor
+    public readonly struct StencilTestDescriptor
     {
         public bool TestEnable { get; }
 

Ryujinx.Graphics.GAL/TextureCreateInfo.cs

@@ -4,7 +4,7 @@ using System.Numerics;
 
 namespace Ryujinx.Graphics.GAL
 {
-    public struct TextureCreateInfo : IEquatable<TextureCreateInfo>
+    public readonly struct TextureCreateInfo : IEquatable<TextureCreateInfo>
     {
         public int Width         { get; }
         public int Height        { get; }
@@ -62,42 +62,42 @@ namespace Ryujinx.Graphics.GAL
             SwizzleA         = swizzleA;
         }
 
-        public readonly int GetMipSize(int level)
+        public int GetMipSize(int level)
         {
             return GetMipStride(level) * GetLevelHeight(level) * GetLevelDepth(level);
         }
 
-        public readonly int GetMipSize2D(int level)
+        public int GetMipSize2D(int level)
         {
             return GetMipStride(level) * GetLevelHeight(level);
         }
 
-        public readonly int GetMipStride(int level)
+        public int GetMipStride(int level)
         {
             return BitUtils.AlignUp(GetLevelWidth(level) * BytesPerPixel, 4);
         }
 
-        private readonly int GetLevelWidth(int level)
+        private int GetLevelWidth(int level)
         {
             return BitUtils.DivRoundUp(GetLevelSize(Width, level), BlockWidth);
         }
 
-        private readonly int GetLevelHeight(int level)
+        private int GetLevelHeight(int level)
         {
             return BitUtils.DivRoundUp(GetLevelSize(Height, level), BlockHeight);
         }
 
-        private readonly int GetLevelDepth(int level)
+        private int GetLevelDepth(int level)
         {
             return Target == Target.Texture3D ? GetLevelSize(Depth, level) : GetLayers();
         }
 
-        public readonly int GetDepthOrLayers()
+        public int GetDepthOrLayers()
         {
             return Target == Target.Texture3D ? Depth : GetLayers();
         }
 
-        public readonly int GetLayers()
+        public int GetLayers()
         {
             if (Target == Target.Texture2DArray ||
                 Target == Target.Texture2DMultisampleArray ||
@@ -113,7 +113,7 @@ namespace Ryujinx.Graphics.GAL
             return 1;
         }
 
-        public readonly int GetLevelsClamped()
+        public int GetLevelsClamped()
         {
             int maxSize = Width;
 

Ryujinx.Graphics.GAL/VertexAttribDescriptor.cs

@@ -1,40 +1,4 @@
-using System;
-
 namespace Ryujinx.Graphics.GAL
 {
-    public struct VertexAttribDescriptor : IEquatable<VertexAttribDescriptor>
-    {
-        public int BufferIndex { get; }
-        public int Offset      { get; }
-
-        public bool IsZero { get; }
-
-        public Format Format { get; }
-
-        public VertexAttribDescriptor(int bufferIndex, int offset, bool isZero, Format format)
-        {
-            BufferIndex = bufferIndex;
-            Offset      = offset;
-            IsZero      = isZero;
-            Format      = format;
-        }
-
-        public override bool Equals(object obj)
-        {
-            return obj is VertexAttribDescriptor other && Equals(other);
-        }
-
-        public bool Equals(VertexAttribDescriptor other)
-        {
-            return BufferIndex == other.BufferIndex &&
-                   Offset      == other.Offset &&
-                   IsZero      == other.IsZero &&
-                   Format      == other.Format;
-        }
-
-        public override int GetHashCode()
-        {
-            return HashCode.Combine(BufferIndex, Offset, IsZero, Format);
-        }
-    }
+    public readonly record struct VertexAttribDescriptor(int BufferIndex, int Offset, bool IsZero, Format Format);
 }

Ryujinx.Graphics.GAL/VertexBufferDescriptor.cs

@@ -1,6 +1,6 @@
 namespace Ryujinx.Graphics.GAL
 {
-    public struct VertexBufferDescriptor
+    public readonly struct VertexBufferDescriptor
     {
         public BufferRange Buffer { get; }
 

Ryujinx.Graphics.GAL/Viewport.cs

@@ -1,6 +1,6 @@
 namespace Ryujinx.Graphics.GAL
 {
-    public struct Viewport
+    public readonly struct Viewport
     {
         public Rectangle<float> Region { get; }