From 0349931f0f4a31b7552b7a0c4165fcbb912b3598 Mon Sep 17 00:00:00 2001
From: Sven Czarnian <devel@svcz.de>
Date: Tue, 25 Oct 2022 14:32:18 +0200
Subject: [PATCH] add a function to project coordinates

---
 src/math/wgs84.ts | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/src/math/wgs84.ts b/src/math/wgs84.ts
index 505c8e1..99d9fd5 100644
--- a/src/math/wgs84.ts
+++ b/src/math/wgs84.ts
@@ -23,4 +23,31 @@ export class WGS84 {
 
     return 2 * EarthRadius * Math.asin(Math.sqrt(a));
   }
+
+  /// @brief Projects coordinate based on the distance and bearing
+  /// @param coordinate The root coordinate
+  /// @param distance The distance in metres
+  /// @param bearing The bearing in degree
+  static project(
+    coordinate: { lat: number; lon: number },
+    distance: number,
+    bearing: number,
+  ): { lat: number; lon: number } {
+    const lat0 = Angle.deg2rad(coordinate.lat);
+    const lon0 = Angle.deg2rad(coordinate.lon);
+    const radians = Angle.deg2rad(bearing);
+
+    const lat1 = Math.asin(
+      Math.sin(lat0) * Math.cos(distance / EarthRadius) +
+        Math.cos(lat0) * Math.sin(distance / EarthRadius) * Math.cos(radians),
+    );
+    const lon1 =
+      lon0 +
+      Math.atan2(
+        Math.sin(radians) * Math.sin(distance / EarthRadius) * Math.cos(lat0),
+        Math.cos(distance / EarthRadius) - Math.sin(lat0) * Math.sin(lat1),
+      );
+
+    return { lat: Angle.rad2deg(lat1), lon: Angle.rad2deg(lon1) };
+  }
 }