From 2329eadae4d9f810b8f07574d9dc9d8d5a37a5e0 Mon Sep 17 00:00:00 2001
From: Sacha Ligthert <sacha@ligthert.net>
Date: Tue, 16 Jan 2024 22:31:18 +0100
Subject: [PATCH] Initial Commit -- JavaScript hilarity ensues from here.

---
 index.html | 89 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 89 insertions(+)
 create mode 100644 index.html
diff --git a/index.html b/index.html
new file mode 100644
index 0000000..f528b29
--- /dev/null
+++ b/index.html
@@ -0,0 +1,89 @@
+<!DOCTYPE html>
+<html>
+<head>
+<meta charset="utf-8" />
+<title>Honestly stolen from BlackSharkDen</title>
+<meta name="viewport" content="initial-scale=1,maximum-scale=1,user-scalable=no" />
+<script src="https://unpkg.com/maplibre-gl@2.4.0/dist/maplibre-gl.js"></script>
+<link href="https://unpkg.com/maplibre-gl@2.4.0/dist/maplibre-gl.css" rel="stylesheet" />
+<style>
+	body { margin: 0; padding: 0; }
+	#map { position: absolute; top: 0; bottom: 0; width: 100%; }
+
+#info {
+display: block;
+position: relative;
+margin: 0px auto;
+width: 50%;
+padding: 10px;
+border: none;
+border-radius: 3px;
+font-size: 12px;
+text-align: center;
+color: #222;
+background: #fff;
+}
+</style>
+</head>
+<body>
+<div id="map"></div>
+<pre id="info"></pre> 
+<script>
+var map = new maplibregl.Map({
+container: 'map',
+style: 'https://api.maptiler.com/maps/topo-v2/style.json?key=<replace-me>',
+center: [42, 42],
+zoom: 7
+});
+ 
+map.on('load', function () {
+
+
+});
+
+
+function MGRSString (Lat, Long) { 
+  //if (Lat < -80) return 'Too far South' ; if (Lat > 84) return 'Too far North' ;
+
+  var c = 1 + Math.floor ((Long+180)/6);
+  var e = c*6 - 183 ;
+  var k = Lat*Math.PI/180;
+  var l = Long*Math.PI/180;
+  var m = e*Math.PI/180;
+  var n = Math.cos (k);
+  var o = 0.006739496819936062*Math.pow (n,2);
+  var p = 40680631590769/(6356752.314*Math.sqrt(1 + o));
+  var q = Math.tan (k);
+  var r = q*q;
+  var s = (r*r*r) - Math.pow (q,6);
+  var t = l - m;
+  var u = 1.0 - r + o;
+  var v = 5.0 - r + 9*o + 4.0*(o*o);
+  var w = 5.0 - 18.0*r + (r*r) + 14.0*o - 58.0*r*o;
+  var x = 61.0 - 58.0*r + (r*r) + 270.0*o - 330.0*r*o;
+  var y = 61.0 - 479.0*r + 179.0*(r*r) - (r*r*r);
+  var z = 1385.0 - 3111.0*r + 543.0*(r*r) - (r*r*r);
+  var aa = p*n*t + (p/6.0*Math.pow (n,3)*u*Math.pow (t,3)) + (p/120.0*Math.pow (n,5)*w*Math.pow (t,5)) + (p/5040.0*Math.pow (n,7)*y*Math.pow (t,7));
+  var ab = 6367449.14570093*(k - (0.00251882794504*Math.sin (2*k)) + (0.00000264354112*Math.sin (4*k)) - (0.00000000345262*Math.sin (6*k)) + (0.000000000004892*Math.sin (8*k))) + (q/2.0*p*Math.pow (n,2)*Math.pow (t,2)) + (q/24.0*p*Math.pow (n,4)*v*Math.pow (t,4)) + (q/720.0*p*Math.pow (n,6)*x*Math.pow (t,6)) + (q/40320.0*p*Math.pow (n,8)*z*Math.pow (t,8));
+  aa = aa*0.9996 + 500000.0;
+  ab = ab*0.9996; if (ab < 0.0) ab += 10000000.0;
+  var ad = 'CDEFGHJKLMNPQRSTUVWXX'.charAt (Math.floor (Lat/8 + 10));
+  var ae = Math.floor (aa/100000);
+  var af = ['ABCDEFGH','JKLMNPQR','STUVWXYZ'][(c-1)%3].charAt (ae-1);
+  var ag = Math.floor (ab/100000)%20;
+  var ah = ['ABCDEFGHJKLMNPQRSTUV','FGHJKLMNPQRSTUVABCDE'][(c-1)%2].charAt (ag);
+  function pad (val) {if (val < 10) {val = '0000' + val} else if (val < 100) {val = '000' + val} else if (val < 1000) {val = '00' + val} else if (val < 10000) {val = '0' + val};return val};
+  aa = Math.floor (aa%100000); aa = pad (aa);
+  ab = Math.floor (ab%100000); ab = pad (ab);
+  return c + ad + ' ' + af + ah + ' ' + aa + ' ' + ab;
+};
+
+map.on('mousemove', function (e) {
+  var coordinate = e.lngLat.wrap();
+  document.getElementById('info').innerHTML = MGRSString(coordinate.lat, coordinate.lng);
+});
+
+</script>
+ 
+</body>
+</html>
