retarget to .net standard 2.0

Bonk/Bonk.csproj

@@ -1,7 +1,7 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <Version>5.0.1</Version>
-    <TargetFramework>netstandard2.1</TargetFramework>
+    <TargetFramework>netstandard2.0</TargetFramework>
     <Description>.NET Core High Performance Collision Detection</Description>
     <PackageId>MoonTools.Core.Bonk</PackageId>
     <RootNamespace>MoonTools.Core.Bonk</RootNamespace>
@@ -19,8 +19,9 @@
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
-    <PackageReference Include="MoonTools.Core.Structs" Version="2.0.0" />
+    <PackageReference Include="MoonTools.Core.Structs" Version="2.1.0"/>
-    <PackageReference Include="morelinq" Version="3.2.0" />
     <PackageReference Include="System.Collections.Immutable" Version="1.6.0"/>
+    <PackageReference Include="System.Numerics.Vectors" Version="4.5.0"/>
+    <PackageReference Include="Microsoft.Bcl.HashCode" Version="1.1.0"/>
   </ItemGroup>
 </Project>

Bonk/Shapes/Polygon.cs

@@ -4,7 +4,6 @@ using System.Collections.Generic;
 using System.Collections.Immutable;
 using System.Numerics;
 using MoonTools.Core.Structs;
-using MoreLinq;
 
 namespace MoonTools.Core.Bonk
 {
@@ -33,7 +32,19 @@ namespace MoonTools.Core.Bonk
 
         public Vector2 Support(Vector2 direction, Transform2D transform)
         {
-            return Vertices.Select(vertex => Vector2.Transform(vertex, transform.TransformMatrix)).MaxBy(transformed => Vector2.Dot(transformed, direction)).First();
+            var maxDotProduct = float.NegativeInfinity;
+            var maxVertex = vertices[0].ToVector2();
+            foreach (var vertex in Vertices)
+            {
+                var transformed = Vector2.Transform(vertex, transform.TransformMatrix);
+                var dot = Vector2.Dot(transformed, direction);
+                if (dot > maxDotProduct)
+                {
+                    maxVertex = transformed;
+                    maxDotProduct = dot;
+                }
+            }
+            return maxVertex;
         }
 
         public AABB AABB(Transform2D Transform2D)

Bonk/Shapes/Rectangle.cs

@@ -3,7 +3,6 @@ using System.Collections.Generic;
 using System.Linq;
 using System.Numerics;
 using MoonTools.Core.Structs;
-using MoreLinq;
 
 namespace MoonTools.Core.Bonk
 {
@@ -38,7 +37,19 @@ namespace MoonTools.Core.Bonk
 
         public Vector2 Support(Vector2 direction, Transform2D transform)
         {
-            return Vertices.Select(vertex => Vector2.Transform(vertex, transform.TransformMatrix)).MaxBy(transformed => Vector2.Dot(transformed, direction)).First();
+            var maxDotProduct = float.NegativeInfinity;
+            var maxVertex = new Vector2(MinX, MinY);
+            foreach (var vertex in Vertices)
+            {
+                var transformed = Vector2.Transform(vertex, transform.TransformMatrix);
+                var dot = Vector2.Dot(transformed, direction);
+                if (dot > maxDotProduct)
+                {
+                    maxVertex = transformed;
+                    maxDotProduct = dot;
+                }
+            }
+            return maxVertex;
         }
 
         public AABB AABB(Transform2D Transform2D)

Bonk/Shapes/Simplex.cs

@@ -2,7 +2,6 @@ using System.Linq;
 using System.Collections.Generic;
 using System.Numerics;
 using MoonTools.Core.Structs;
-using MoreLinq;
 using System;
 
 namespace MoonTools.Core.Bonk
@@ -62,14 +61,21 @@ namespace MoonTools.Core.Bonk
             return Bonk.AABB.FromTransformedVertices(Vertices, transform);
         }
 
-        public Vector2 Support(Vector2 direction)
-        {
-            return Vertices.MaxBy(vertex => Vector2.Dot(vertex, direction)).First();
-        }
-
         public Vector2 Support(Vector2 direction, Transform2D transform)
         {
-            return Vector2.Transform(Support(direction), transform.TransformMatrix);
+            var maxDotProduct = float.NegativeInfinity;
+            var maxVertex = a;
+            foreach (var vertex in Vertices)
+            {
+                var transformed = Vector2.Transform(vertex, transform.TransformMatrix);
+                var dot = Vector2.Dot(transformed, direction);
+                if (dot > maxDotProduct)
+                {
+                    maxVertex = transformed;
+                    maxDotProduct = dot;
+                }
+            }
+            return maxVertex;
         }
 
         public override bool Equals(object obj)