[Math] Add ToString override for Color/Color32;

[Rendering] Fix a bug with ShaderHandle reference checking;
[Serialization] Add GuidHasher Equality support;

Author: LittleCodingFox

Engine/Staple.Core/Math/Color.cs

@@ -142,6 +142,11 @@ public override readonly bool Equals(object obj)
         return false;
     }
 
+    public override string ToString()
+    {
+        return $"({r}, {g}, {b}, {a})";
+    }
+
     /// <summary>
     /// Mixes two colors
     /// </summary>

Engine/Staple.Core/Math/Color32.cs

@@ -146,6 +146,11 @@ public override readonly bool Equals(object obj)
         return false;
     }
 
+    public override string ToString()
+    {
+        return $"({r}, {g}, {b}, {a})";
+    }
+
     /// <summary>
     /// Mixes two colors
     /// </summary>

Engine/Staple.Core/Rendering/Shader/ShaderHandle.cs

@@ -7,16 +7,16 @@ namespace Staple.Internal;
 /// Direct access to a shader uniform, used for caching.
 /// </summary>
 /// <param name="uniform">The uniform to store</param>
-public readonly struct ShaderHandle(object owner, Shader.UniformInfo uniform)
+public readonly struct ShaderHandle(IGuidAsset owner, Shader.UniformInfo uniform)
 {
     internal readonly Shader.UniformInfo uniform = uniform;
     internal readonly WeakReference<object> owner = new(owner);
 
-    internal bool TryGetUniform(object owner, out Shader.UniformInfo uniform)
+    internal bool TryGetUniform(IGuidAsset owner, out Shader.UniformInfo uniform)
     {
         if(IsValid &&
             this.owner.TryGetTarget(out var actualOwner) &&
-            ReferenceEquals(actualOwner, owner))
+            ((IGuidAsset)actualOwner).Guid.GuidHash == owner.Guid.GuidHash)
         {
             uniform = this.uniform;
 

Engine/Staple.Core/Serialization/Asset/GuidHasher.cs

@@ -1,9 +1,12 @@
-namespace Staple;
+using System;
+using System.Diagnostics.CodeAnalysis;
+
+namespace Staple;
 
 /// <summary>
 /// Manages a Guid Hash for faster Guid comparisons
 /// </summary>
-public class GuidHasher
+public class GuidHasher : IEquatable<GuidHasher>
 {
     private string guid;
 
@@ -21,6 +24,31 @@ public string Guid
         }
     }
 
+    public static bool operator==(GuidHasher lhs, GuidHasher rhs)
+    {
+        return lhs.GuidHash == rhs.GuidHash;
+    }
+
+    public static bool operator !=(GuidHasher lhs, GuidHasher rhs)
+    {
+        return lhs.GuidHash != rhs.GuidHash;
+    }
+
+    public override bool Equals(object obj)
+    {
+        return obj is GuidHasher hasher && this == hasher;
+    }
+
+    public bool Equals(GuidHasher other)
+    {
+        return this == other;
+    }
+
+    public override int GetHashCode()
+    {
+        return HashCode.Combine(Guid, GuidHash);
+    }
+
     public override string ToString()
     {
         return guid;