Move Swiss transform functions to the .js file

examples/wms-custom-proj.js

@@ -9,6 +9,7 @@ goog.require('ol.proj.Projection');
 goog.require('ol.source.TileWMS');
 
 
+
 var projection = new ol.proj.Projection({
   code: 'EPSG:21781',
   // The extent is used to determine zoom level 0. Recommended values for a
@@ -17,8 +18,6 @@ var projection = new ol.proj.Projection({
   units: 'm'
 });
 ol.proj.addProjection(projection);
-// WGStoCHx, WGStoCHy, CHtoWGSlng and CHtoWGSlat are defined in a script block
-// in the html.
 ol.proj.addCoordinateTransforms('EPSG:4326', projection,
     function(coordinate) {
       return [
@@ -86,3 +85,155 @@ var map = new ol.Map({
     zoom: 2
   })
 });
+
+
+
+/*
+ * Swiss projection transform functions downloaded from
+ * http://www.swisstopo.admin.ch/internet/swisstopo/en/home/products/software/products/skripts.html
+ */
+
+// Convert WGS lat/long (° dec) to CH y
+function WGStoCHy(lat, lng) {
+
+  // Converts degrees dec to sex
+  lat = DECtoSEX(lat);
+  lng = DECtoSEX(lng);
+
+  // Converts degrees to seconds (sex)
+  lat = DEGtoSEC(lat);
+  lng = DEGtoSEC(lng);
+
+  // Axiliary values (% Bern)
+  var lat_aux = (lat - 169028.66) / 10000;
+  var lng_aux = (lng - 26782.5) / 10000;
+
+  // Process Y
+  var y = 600072.37 +
+      211455.93 * lng_aux -
+      10938.51 * lng_aux * lat_aux -
+      0.36 * lng_aux * Math.pow(lat_aux, 2) -
+      44.54 * Math.pow(lng_aux, 3);
+
+  return y;
+}
+
+// Convert WGS lat/long (° dec) to CH x
+function WGStoCHx(lat, lng) {
+
+  // Converts degrees dec to sex
+  lat = DECtoSEX(lat);
+  lng = DECtoSEX(lng);
+
+  // Converts degrees to seconds (sex)
+  lat = DEGtoSEC(lat);
+  lng = DEGtoSEC(lng);
+
+  // Axiliary values (% Bern)
+  var lat_aux = (lat - 169028.66) / 10000;
+  var lng_aux = (lng - 26782.5) / 10000;
+
+  // Process X
+  var x = 200147.07 +
+      308807.95 * lat_aux +
+      3745.25 * Math.pow(lng_aux, 2) +
+      76.63 * Math.pow(lat_aux, 2) -
+      194.56 * Math.pow(lng_aux, 2) * lat_aux +
+      119.79 * Math.pow(lat_aux, 3);
+
+  return x;
+
+}
+
+
+// Convert CH y/x to WGS lat
+function CHtoWGSlat(y, x) {
+
+  // Converts militar to civil and  to unit = 1000km
+  // Axiliary values (% Bern)
+  var y_aux = (y - 600000) / 1000000;
+  var x_aux = (x - 200000) / 1000000;
+
+  // Process lat
+  var lat = 16.9023892 +
+      3.238272 * x_aux -
+      0.270978 * Math.pow(y_aux, 2) -
+      0.002528 * Math.pow(x_aux, 2) -
+      0.0447 * Math.pow(y_aux, 2) * x_aux -
+      0.0140 * Math.pow(x_aux, 3);
+
+  // Unit 10000" to 1 " and converts seconds to degrees (dec)
+  lat = lat * 100 / 36;
+
+  return lat;
+
+}
+
+// Convert CH y/x to WGS long
+function CHtoWGSlng(y, x) {
+
+  // Converts militar to civil and  to unit = 1000km
+  // Axiliary values (% Bern)
+  var y_aux = (y - 600000) / 1000000;
+  var x_aux = (x - 200000) / 1000000;
+
+  // Process long
+  var lng = 2.6779094 +
+      4.728982 * y_aux +
+      0.791484 * y_aux * x_aux +
+      0.1306 * y_aux * Math.pow(x_aux, 2) -
+      0.0436 * Math.pow(y_aux, 3);
+
+  // Unit 10000" to 1 " and converts seconds to degrees (dec)
+  lng = lng * 100 / 36;
+
+  return lng;
+
+}
+
+
+// Convert SEX DMS angle to DEC
+function SEXtoDEC(angle) {
+
+  // Extract DMS
+  var deg = parseInt(angle, 10);
+  var min = parseInt((angle - deg) * 100, 10);
+  var sec = (((angle - deg) * 100) - min) * 100;
+
+  // Result in degrees sex (dd.mmss)
+  return deg + (sec / 60 + min) / 60;
+
+}
+
+// Convert DEC angle to SEX DMS
+function DECtoSEX(angle) {
+
+  // Extract DMS
+  var deg = parseInt(angle, 10);
+  var min = parseInt((angle - deg) * 60, 10);
+  var sec = (((angle - deg) * 60) - min) * 60;
+
+  // Result in degrees sex (dd.mmss)
+  return deg + min / 100 + sec / 10000;
+
+}
+
+// Convert Degrees angle to seconds
+function DEGtoSEC(angle) {
+
+  // Extract DMS
+  var deg = parseInt(angle, 10);
+  var min = parseInt((angle - deg) * 100, 10);
+  var sec = (((angle - deg) * 100) - min) * 100;
+
+  // Avoid rounding problems with seconds=0
+  var parts = String(angle).split('.');
+  if (parts.length == 2 && parts[1].length == 2) {
+    min = Number(parts[1]);
+    sec = 0;
+  }
+
+  // Result in degrees sex (dd.mmss)
+  return sec + min * 60 + deg * 3600;
+
+}