From d9bc05ee3210c336814698cb541b632661931125 Mon Sep 17 00:00:00 2001
From: Evan Hemsley <2342303+ehemsley@users.noreply.github.com>
Date: Sun, 29 Dec 2019 21:09:28 -0800
Subject: [PATCH] remove linq methods from AABB calculation

---
 Bonk/AABB.cs                   | 36 ++++++++++++++++++++++++++++------
 Bonk/BroadPhase/SpatialHash.cs |  4 ----
 2 files changed, 30 insertions(+), 10 deletions(-)

diff --git a/Bonk/AABB.cs b/Bonk/AABB.cs
index b525cd3..0ecbfdd 100644
--- a/Bonk/AABB.cs
+++ b/Bonk/AABB.cs
@@ -1,6 +1,5 @@
 using System;
 using System.Collections.Generic;
-using System.Linq;
 using System.Numerics;
 using MoonTools.Core.Structs;
 
@@ -21,14 +20,39 @@ namespace MoonTools.Core.Bonk
 
         public static AABB FromTransformedVertices(IEnumerable<Position2D> vertices, Transform2D transform)
         {
-            var TransformedVertices = vertices.Select(vertex => Vector2.Transform(vertex, transform.TransformMatrix));
+            float minX = float.MaxValue;
+            float minY = float.MaxValue;
+            float maxX = float.MinValue;
+            float maxY = float.MinValue;
+
+            foreach (var vertex in vertices)
+            {
+                var transformedVertex = Vector2.Transform(vertex, transform.TransformMatrix);
+
+                if (transformedVertex.X < minX)
+                {
+                    minX = transformedVertex.X;
+                }
+                if (transformedVertex.Y < minY)
+                {
+                    minY = transformedVertex.Y;
+                }
+                if (transformedVertex.X > maxX)
+                {
+                    maxX = transformedVertex.X;
+                }
+                if (transformedVertex.Y > maxY)
+                {
+                    maxY = transformedVertex.Y;
+                }
+            }
 
             return new AABB
             {
-                MinX = TransformedVertices.Min(vertex => vertex.X),
-                MinY = TransformedVertices.Min(vertex => vertex.Y),
-                MaxX = TransformedVertices.Max(vertex => vertex.X),
-                MaxY = TransformedVertices.Max(vertex => vertex.Y)
+                MinX = minX,
+                MinY = minY,
+                MaxX = maxX,
+                MaxY = maxY
             };
         }
 
diff --git a/Bonk/BroadPhase/SpatialHash.cs b/Bonk/BroadPhase/SpatialHash.cs
index 9e5b953..05f0099 100644
--- a/Bonk/BroadPhase/SpatialHash.cs
+++ b/Bonk/BroadPhase/SpatialHash.cs
@@ -33,8 +33,6 @@ namespace MoonTools.Core.Bonk
         /// <param name="transform2D"></param>
         public void Insert(T id, IShape2D shape, Transform2D transform2D)
         {
-            if (shape == null) { throw new ArgumentNullException(nameof(shape)); }
-
             var box = shape.AABB(transform2D);
             var minHash = Hash(box.MinX, box.MinY);
             var maxHash = Hash(box.MaxX, box.MaxY);
@@ -64,8 +62,6 @@ namespace MoonTools.Core.Bonk
         /// </summary>
         public IEnumerable<(T, IShape2D, Transform2D)> Retrieve(T id, IShape2D shape, Transform2D transform2D)
         {
-            if (shape == null) { throw new ArgumentNullException(paramName: nameof(shape)); }
-
             AABB box = shape.AABB(transform2D);
             var minHash = Hash(box.MinX, box.MinY);
             var maxHash = Hash(box.MaxX, box.MaxY);