From 0c3bf48d2c0b5fadef88f7af4d452ff160747d9e Mon Sep 17 00:00:00 2001
From: Syntriax <syntriax@gmail.com>
Date: Wed, 24 Jan 2024 12:31:53 +0300
Subject: [PATCH] feat: Vector2D.Orientation

---
 Engine.Core/Vector2D.cs | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/Engine.Core/Vector2D.cs b/Engine.Core/Vector2D.cs
index 336fd4e..3f8292f 100644
--- a/Engine.Core/Vector2D.cs
+++ b/Engine.Core/Vector2D.cs
@@ -49,6 +49,23 @@ public record Vector2D(float X, float Y)
     public static float Angle(Vector2D left, Vector2D right) => MathF.Acos(Dot(left, right) / (Length(left) * Length(right)));
     public static float Dot(Vector2D left, Vector2D right) => left.X * right.X + left.Y * right.Y;
 
+    /// <summary>
+    /// Finds the Orientation of 3 <see cref="Vector2D"/>s
+    /// </summary>
+    /// <returns>0 -> Collinear, 1 -> Clockwise, 2 -> Counterclockwise</returns>
+    public static int Orientation(Vector2D left, Vector2D middle, Vector2D right)
+    {
+        Vector2D leftToMiddle = left.FromTo(middle);
+        Vector2D middleToRight = middle.FromTo(right);
+
+        float value = leftToMiddle.Y * middleToRight.X -
+                    leftToMiddle.X * middleToRight.Y;
+
+        if (value > 0) return 1;
+        if (value < 0) return 2;
+        return 0;
+    }
+
     public static bool ApproximatelyEquals(Vector2D left, Vector2D right, float epsilon = float.Epsilon)
         => left.X.ApproximatelyEquals(right.X, epsilon) && left.Y.ApproximatelyEquals(right.Y, epsilon);