Add readonly modifier on struct methods.

osu.Framework/Allocation/ValueInvokeOnDisposal.cs

@@ -15,7 +15,7 @@ namespace osu.Framework.Allocation
     ///
     /// This is a struct version of <see cref="InvokeOnDisposal"/> to be used when allocations are to be minimised.
     /// </summary>
-    public struct ValueInvokeOnDisposal : IDisposable
+    public readonly struct ValueInvokeOnDisposal : IDisposable
     {
         private readonly Action action;
 

osu.Framework/Audio/Track/TrackAmplitudes.cs

@@ -10,9 +10,9 @@ public struct TrackAmplitudes
         public float LeftChannel;
         public float RightChannel;
 
-        public float Maximum => Math.Max(LeftChannel, RightChannel);
+        public readonly float Maximum => Math.Max(LeftChannel, RightChannel);
 
-        public float Average => (LeftChannel + RightChannel) / 2;
+        public readonly float Average => (LeftChannel + RightChannel) / 2;
 
         /// <summary>
         /// 256 length array of bins containing the average frequency of both channels at every ~78Hz step of the audible spectrum (0Hz - 20,000Hz).

osu.Framework/Graphics/BlendingParameters.cs

@@ -138,55 +138,55 @@ public void ApplyDefaultToInherited()
                 AlphaEquation = BlendingEquation.Add;
         }
 
-        public bool Equals(BlendingParameters other) =>
+        public readonly bool Equals(BlendingParameters other) =>
             other.Source == Source
             && other.Destination == Destination
             && other.SourceAlpha == SourceAlpha
             && other.DestinationAlpha == DestinationAlpha
             && other.RGBEquation == RGBEquation
             && other.AlphaEquation == AlphaEquation;
 
-        public bool IsDisabled =>
+        public readonly bool IsDisabled =>
             Source == BlendingType.One
             && Destination == BlendingType.Zero
             && SourceAlpha == BlendingType.One
             && DestinationAlpha == BlendingType.Zero
             && RGBEquation == BlendingEquation.Add
             && AlphaEquation == BlendingEquation.Add;
 
-        public override string ToString() => $"BlendingParameter: Factor: {Source}/{Destination}/{SourceAlpha}/{DestinationAlpha} RGBEquation: {RGBEquation} AlphaEquation: {AlphaEquation}";
+        public override readonly string ToString() => $"BlendingParameter: Factor: {Source}/{Destination}/{SourceAlpha}/{DestinationAlpha} RGBEquation: {RGBEquation} AlphaEquation: {AlphaEquation}";
 
         #region GL Type Getters
 
         /// <summary>
         /// Gets the <see cref="BlendEquationMode"/> for the currently specified RGB Equation.
         /// </summary>
-        public BlendEquationMode RGBEquationMode => translateEquation(RGBEquation);
+        public readonly BlendEquationMode RGBEquationMode => translateEquation(RGBEquation);
 
         /// <summary>
         /// Gets the <see cref="BlendEquationMode"/> for the currently specified Alpha Equation.
         /// </summary>
-        public BlendEquationMode AlphaEquationMode => translateEquation(AlphaEquation);
+        public readonly BlendEquationMode AlphaEquationMode => translateEquation(AlphaEquation);
 
         /// <summary>
         /// Gets the <see cref="BlendingFactorSrc"/> for the currently specified source blending mode.
         /// </summary>
-        public BlendingFactorSrc SourceBlendingFactor => translateBlendingFactorSrc(Source);
+        public readonly BlendingFactorSrc SourceBlendingFactor => translateBlendingFactorSrc(Source);
 
         /// <summary>
         /// Gets the <see cref="BlendingFactorDest"/> for the currently specified destination blending mode.
         /// </summary>
-        public BlendingFactorDest DestinationBlendingFactor => translateBlendingFactorDest(Destination);
+        public readonly BlendingFactorDest DestinationBlendingFactor => translateBlendingFactorDest(Destination);
 
         /// <summary>
         /// Gets the <see cref="BlendingFactorSrc"/> for the currently specified source alpha mode.
         /// </summary>
-        public BlendingFactorSrc SourceAlphaBlendingFactor => translateBlendingFactorSrc(SourceAlpha);
+        public readonly BlendingFactorSrc SourceAlphaBlendingFactor => translateBlendingFactorSrc(SourceAlpha);
 
         /// <summary>
         /// Gets the <see cref="BlendingFactorDest"/> for the currently specified destination alpha mode.
         /// </summary>
-        public BlendingFactorDest DestinationAlphaBlendingFactor => translateBlendingFactorDest(DestinationAlpha);
+        public readonly BlendingFactorDest DestinationAlphaBlendingFactor => translateBlendingFactorDest(DestinationAlpha);
 
         private static BlendingFactorSrc translateBlendingFactorSrc(BlendingType factor)
         {

osu.Framework/Graphics/Colour/ColourInfo.cs

@@ -66,7 +66,7 @@ public static ColourInfo GradientVertical(SRGBColour c1, SRGBColour c2)
 
         private SRGBColour singleColour
         {
-            get
+            readonly get
             {
                 if (!HasSingleColour)
                     throw new InvalidOperationException("Attempted to read single colour from multi-colour ColourInfo.");
@@ -81,7 +81,7 @@ private SRGBColour singleColour
             }
         }
 
-        public SRGBColour Interpolate(Vector2 interp) => SRGBColour.FromVector(
+        public readonly SRGBColour Interpolate(Vector2 interp) => SRGBColour.FromVector(
             (1 - interp.Y) * ((1 - interp.X) * TopLeft.ToVector() + interp.X * TopRight.ToVector()) +
             interp.Y * ((1 - interp.X) * BottomLeft.ToVector() + interp.X * BottomRight.ToVector()));
 
@@ -128,7 +128,7 @@ public void ApplyChild(ColourInfo childColour, Quad interp)
         /// </summary>
         /// <param name="alpha">The alpha parameter to multiply the alpha values of all vertices with.</param>
         /// <returns>The new ColourInfo.</returns>
-        public ColourInfo MultiplyAlpha(float alpha)
+        public readonly ColourInfo MultiplyAlpha(float alpha)
         {
             if (alpha == 1.0)
                 return this;
@@ -148,7 +148,7 @@ public ColourInfo MultiplyAlpha(float alpha)
             return result;
         }
 
-        public bool Equals(ColourInfo other)
+        public readonly bool Equals(ColourInfo other)
         {
             if (!HasSingleColour)
             {
@@ -165,12 +165,12 @@ public bool Equals(ColourInfo other)
             return other.HasSingleColour && TopLeft.Equals(other.TopLeft);
         }
 
-        public bool Equals(SRGBColour other) => HasSingleColour && TopLeft.Equals(other);
+        public readonly bool Equals(SRGBColour other) => HasSingleColour && TopLeft.Equals(other);
 
         /// <summary>
         /// The average colour of all corners.
         /// </summary>
-        public SRGBColour AverageColour
+        public readonly SRGBColour AverageColour
         {
             get
             {
@@ -185,7 +185,7 @@ public SRGBColour AverageColour
         /// <summary>
         /// The maximum alpha value of all four corners.
         /// </summary>
-        public float MaxAlpha
+        public readonly float MaxAlpha
         {
             get
             {
@@ -201,7 +201,7 @@ public float MaxAlpha
         /// <summary>
         /// The minimum alpha value of all four corners.
         /// </summary>
-        public float MinAlpha
+        public readonly float MinAlpha
         {
             get
             {
@@ -214,7 +214,7 @@ public float MinAlpha
             }
         }
 
-        public override string ToString() => HasSingleColour ? $@"{TopLeft} (Single)" : $@"{TopLeft}, {TopRight}, {BottomLeft}, {BottomRight}";
+        public override readonly string ToString() => HasSingleColour ? $@"{TopLeft} (Single)" : $@"{TopLeft}, {TopRight}, {BottomLeft}, {BottomRight}";
 
         public static implicit operator ColourInfo(SRGBColour colour) => SingleColour(colour);
         public static implicit operator SRGBColour(ColourInfo colour) => colour.singleColour;

osu.Framework/Graphics/Colour/SRGBColour.cs

@@ -56,7 +56,7 @@ public struct SRGBColour : IEquatable<SRGBColour>
                 first.Linear.A + second.Linear.A),
         };
 
-        public Vector4 ToVector() => new Vector4(Linear.R, Linear.G, Linear.B, Linear.A);
+        public readonly Vector4 ToVector() => new Vector4(Linear.R, Linear.G, Linear.B, Linear.A);
         public static SRGBColour FromVector(Vector4 v) => new SRGBColour { Linear = new Color4(v.X, v.Y, v.Z, v.W) };
 
         /// <summary>
@@ -65,7 +65,7 @@ public struct SRGBColour : IEquatable<SRGBColour>
         /// <param name="alpha">The alpha factor to multiply with.</param>
         public void MultiplyAlpha(float alpha) => Linear.A *= alpha;
 
-        public bool Equals(SRGBColour other) => Linear.Equals(other.Linear);
-        public override string ToString() => Linear.ToString();
+        public readonly bool Equals(SRGBColour other) => Linear.Equals(other.Linear);
+        public override readonly string ToString() => Linear.ToString();
     }
 }

osu.Framework/Graphics/Containers/Container.cs

@@ -449,9 +449,9 @@ internal Enumerator(Container<T> container)
 
             public void Reset() => currentIndex = -1;
 
-            public T Current => container[currentIndex];
+            public readonly T Current => container[currentIndex];
 
-            object IEnumerator.Current => Current;
+            readonly object IEnumerator.Current => Current;
 
             public void Dispose()
             {

osu.Framework/Graphics/Containers/LifetimeManagementContainer.cs

@@ -395,6 +395,6 @@ public LifetimeBoundaryCrossedEvent(Drawable child, LifetimeBoundaryKind kind, L
             Direction = direction;
         }
 
-        public override string ToString() => $"({Child.ChildID}, {Kind}, {Direction})";
+        public override readonly string ToString() => $"({Child.ChildID}, {Kind}, {Direction})";
     }
 }

osu.Framework/Graphics/DrawColourInfo.cs

@@ -18,6 +18,6 @@ public DrawColourInfo(ColourInfo? colour = null, BlendingParameters? blending =
             Blending = blending ?? BlendingParameters.Inherit;
         }
 
-        public bool Equals(DrawColourInfo other) => Colour.Equals(other.Colour) && Blending.Equals(other.Blending);
+        public readonly bool Equals(DrawColourInfo other) => Colour.Equals(other.Colour) && Blending.Equals(other.Blending);
     }
 }

osu.Framework/Graphics/DrawInfo.cs

@@ -68,8 +68,8 @@ public void ApplyTransform(Vector2 translation, Vector2 scale, float rotation, V
             //MatrixExtensions.FastInvert(ref target.MatrixInverse);
         }
 
-        public bool Equals(DrawInfo other) => Matrix.Equals(other.Matrix);
+        public readonly bool Equals(DrawInfo other) => Matrix.Equals(other.Matrix);
 
-        public override string ToString() => $@"{GetType().ReadableName().Replace(@"DrawInfo", string.Empty)} DrawInfo";
+        public override readonly string ToString() => $@"{GetType().ReadableName().Replace(@"DrawInfo", string.Empty)} DrawInfo";
     }
 }

osu.Framework/Graphics/Effects/EdgeEffectParameters.cs

@@ -46,13 +46,13 @@ public struct EdgeEffectParameters : IEquatable<EdgeEffectParameters>
         /// </summary>
         public bool Hollow;
 
-        public bool Equals(EdgeEffectParameters other) =>
+        public readonly bool Equals(EdgeEffectParameters other) =>
             Colour.Equals(other.Colour) &&
             Offset == other.Offset &&
             Type == other.Type &&
             Roundness == other.Roundness &&
             Radius == other.Radius;
 
-        public override string ToString() => Type != EdgeEffectType.None ? $@"{Radius} {Type}EdgeEffect" : @"EdgeEffect (Disabled)";
+        public override readonly string ToString() => Type != EdgeEffectType.None ? $@"{Radius} {Type}EdgeEffect" : @"EdgeEffect (Disabled)";
     }
 }

osu.Framework/Graphics/MarginPadding.cs

@@ -43,7 +43,7 @@ public struct MarginPadding : IEquatable<MarginPadding>
         /// the absolute size of the space left empty from the right and left of the container if used as padding.
         /// Effectively <see cref="Right"/> + <see cref="Left"/>.
         /// </summary>
-        public float TotalHorizontal => Left + Right;
+        public readonly float TotalHorizontal => Left + Right;
 
         /// <summary>
         /// Sets the values of both <see cref="Left"/> and <see cref="Right"/> to the assigned value.
@@ -58,7 +58,7 @@ public float Horizontal
         /// the absolute size of the space left empty from the top and bottom of the container if used as padding.
         /// Effectively <see cref="Top"/> + <see cref="Bottom"/>.
         /// </summary>
-        public float TotalVertical => Top + Bottom;
+        public readonly float TotalVertical => Top + Bottom;
 
         /// <summary>
         /// Sets the values of both <see cref="Top"/> and <see cref="Bottom"/> to the assigned value.
@@ -71,7 +71,7 @@ public float Vertical
         /// <summary>
         /// Gets the total absolute size of the empty space horizontally (x coordinate) and vertically (y coordinate) around the <see cref="Drawable"/> or inside the container if used as padding.
         /// </summary>
-        public Vector2 Total => new Vector2(TotalHorizontal, TotalVertical);
+        public readonly Vector2 Total => new Vector2(TotalHorizontal, TotalVertical);
 
         /// <summary>
         /// Initializes all four sides (<see cref="Left"/>, <see cref="Right"/>, <see cref="Top"/> and <see cref="Bottom"/>) to the given value.
@@ -82,9 +82,9 @@ public MarginPadding(float allSides)
             Top = Left = Bottom = Right = allSides;
         }
 
-        public bool Equals(MarginPadding other) => Top == other.Top && Left == other.Left && Bottom == other.Bottom && Right == other.Right;
+        public readonly bool Equals(MarginPadding other) => Top == other.Top && Left == other.Left && Bottom == other.Bottom && Right == other.Right;
 
-        public override string ToString() => $@"({Top}, {Left}, {Bottom}, {Right})";
+        public override readonly string ToString() => $@"({Top}, {Left}, {Bottom}, {Right})";
 
         public static MarginPadding operator -(MarginPadding mp) =>
             new MarginPadding

osu.Framework/Graphics/OpenGL/GLWrapper.cs

@@ -851,7 +851,7 @@ public struct MaskingInfo : IEquatable<MaskingInfo>
         public bool Hollow;
         public float HollowCornerRadius;
 
-        public bool Equals(MaskingInfo other) =>
+        public readonly bool Equals(MaskingInfo other) =>
             ScreenSpaceAABB == other.ScreenSpaceAABB &&
             MaskingRect == other.MaskingRect &&
             ToMaskingSpace == other.ToMaskingSpace &&

osu.Framework/Graphics/OpenGL/Vertices/DepthWrappingVertex.cs

@@ -16,7 +16,7 @@ internal struct DepthWrappingVertex<TVertex> : IVertex, IEquatable<DepthWrapping
         [VertexMember(1, VertexAttribPointerType.Float)]
         public float BackbufferDrawDepth;
 
-        public bool Equals(DepthWrappingVertex<TVertex> other)
+        public readonly bool Equals(DepthWrappingVertex<TVertex> other)
             => Vertex.Equals(other.Vertex)
                && BackbufferDrawDepth.Equals(other.BackbufferDrawDepth);
     }

osu.Framework/Graphics/OpenGL/Vertices/ParticleVertex2D.cs

@@ -27,6 +27,6 @@ public struct ParticleVertex2D : IEquatable<ParticleVertex2D>, IVertex
         [VertexMember(2, VertexAttribPointerType.Float)]
         public Vector2 Direction;
 
-        public bool Equals(ParticleVertex2D other) => Position.Equals(other.Position) && TexturePosition.Equals(other.TexturePosition) && Colour.Equals(other.Colour) && Time.Equals(other.Time) && Direction.Equals(other.Direction);
+        public readonly bool Equals(ParticleVertex2D other) => Position.Equals(other.Position) && TexturePosition.Equals(other.TexturePosition) && Colour.Equals(other.Colour) && Time.Equals(other.Time) && Direction.Equals(other.Direction);
     }
 }

osu.Framework/Graphics/OpenGL/Vertices/TexturedVertex2D.cs

@@ -27,7 +27,7 @@ public struct TexturedVertex2D : IEquatable<TexturedVertex2D>, IVertex
         [VertexMember(2, VertexAttribPointerType.Float)]
         public Vector2 BlendRange;
 
-        public bool Equals(TexturedVertex2D other) =>
+        public readonly bool Equals(TexturedVertex2D other) =>
             Position.Equals(other.Position)
             && TexturePosition.Equals(other.TexturePosition)
             && Colour.Equals(other.Colour)

osu.Framework/Graphics/OpenGL/Vertices/TexturedVertex3D.cs

@@ -21,6 +21,6 @@ public struct TexturedVertex3D : IEquatable<TexturedVertex3D>, IVertex
         [VertexMember(2, VertexAttribPointerType.Float)]
         public Vector2 TexturePosition;
 
-        public bool Equals(TexturedVertex3D other) => Position.Equals(other.Position) && TexturePosition.Equals(other.TexturePosition) && Colour.Equals(other.Colour);
+        public readonly bool Equals(TexturedVertex3D other) => Position.Equals(other.Position) && TexturePosition.Equals(other.TexturePosition) && Colour.Equals(other.Colour);
     }
 }

osu.Framework/Graphics/OpenGL/Vertices/TimedTexturedVertex2D.cs

@@ -24,6 +24,6 @@ public struct TimedTexturedVertex2D : IEquatable<TimedTexturedVertex2D>, IVertex
         [VertexMember(1, VertexAttribPointerType.Float)]
         public float Time;
 
-        public bool Equals(TimedTexturedVertex2D other) => Position.Equals(other.Position) && TexturePosition.Equals(other.TexturePosition) && Colour.Equals(other.Colour) && Time.Equals(other.Time);
+        public readonly bool Equals(TimedTexturedVertex2D other) => Position.Equals(other.Position) && TexturePosition.Equals(other.TexturePosition) && Colour.Equals(other.Colour) && Time.Equals(other.Time);
     }
 }

osu.Framework/Graphics/OpenGL/Vertices/UncolouredVertex2D.cs

@@ -14,6 +14,6 @@ public struct UncolouredVertex2D : IEquatable<UncolouredVertex2D>, IVertex
         [VertexMember(2, VertexAttribPointerType.Float)]
         public Vector2 Position;
 
-        public bool Equals(UncolouredVertex2D other) => Position.Equals(other.Position);
+        public readonly bool Equals(UncolouredVertex2D other) => Position.Equals(other.Position);
     }
 }

osu.Framework/Graphics/OpenGL/Vertices/Vertex2D.cs

@@ -18,6 +18,6 @@ public struct Vertex2D : IEquatable<Vertex2D>, IVertex
         [VertexMember(4, VertexAttribPointerType.Float)]
         public Color4 Colour;
 
-        public bool Equals(Vertex2D other) => Position.Equals(other.Position) && Colour.Equals(other.Colour);
+        public readonly bool Equals(Vertex2D other) => Position.Equals(other.Position) && Colour.Equals(other.Colour);
     }
 }

osu.Framework/Graphics/Primitives/ProjectionRange.cs

@@ -10,7 +10,7 @@ namespace osu.Framework.Graphics.Primitives
     /// A structure that tells how "far" along an axis
     /// the projection of vertices onto the axis would be.
     /// </summary>
-    internal struct ProjectionRange
+    internal readonly struct ProjectionRange
     {
         /// <summary>
         /// The minimum projected value.