From ef94ddb89aa3b0882aa3c254b8601f8fb5a53e49 Mon Sep 17 00:00:00 2001
From: Thombrix <bruno.thomas-caruso@outlook.com>
Date: Sun, 26 Nov 2023 00:33:53 +0100
Subject: [PATCH] Added a math utility class to do distance and direction
 calculations between two lat lon coordinates

---
 backend-laravel/app/Utility/Math.php | 46 ++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)
 create mode 100644 backend-laravel/app/Utility/Math.php

diff --git a/backend-laravel/app/Utility/Math.php b/backend-laravel/app/Utility/Math.php
new file mode 100644
index 0000000..e670a37
--- /dev/null
+++ b/backend-laravel/app/Utility/Math.php
@@ -0,0 +1,46 @@
+<?php
+
+namespace App\Utility;
+
+class Math 
+{
+    public static $earthRadius = 6371;
+
+    public static function distance($lat1, $lon1, $lat2, $lon2)
+    {
+        $lat1 = deg2rad($lat1);
+        $lon1 = deg2rad($lon1);
+        $lat2 = deg2rad($lat2);
+        $lon2 = deg2rad($lon2);
+
+        $latDiff = $lat2 - $lat1;
+        $lonDiff = $lon2 - $lon1;
+
+        $a = sin($latDiff / 2) ** 2 + cos($lat1) * cos($lat2) * sin($lonDiff / 2) ** 2;
+        $c = 2 * atan2(sqrt($a), sqrt(1 - $a));
+
+        $distance = self::$earthRadius * $c;
+
+        return $distance;
+    }
+
+    public static function direction($lat1, $lon1, $lat2, $lon2)
+    {
+        $lat1 = deg2rad($lat1);
+        $lon1 = deg2rad($lon1);
+        $lat2 = deg2rad($lat2);
+        $lon2 = deg2rad($lon2); 
+        
+        $lonDiff = $lon2 - $lon1;
+        
+        $y = sin($lonDiff) * cos($lat2);
+        $x = cos($lat1) * sin($lat2) - sin($lat1) * cos($lat2) * cos($lonDiff);
+
+        $bearing = atan2($y, $x);
+        $bearing = rad2deg($bearing);
+
+        $bearing = ($bearing + 360) % 360;
+    
+        return $bearing;
+    }
+}
\ No newline at end of file