From 3e8ce840c70ee00925210b96738696d1dc445f8f Mon Sep 17 00:00:00 2001
From: Rutger Broekhoff
Date: Tue, 8 Sep 2026 01:36:38 +0200
Subject: UTM projection

---
 server/src/datex2.cpp | 62 ++++++++++++++++++++++++++++++++++++++-------------
 1 file changed, 47 insertions(+), 15 deletions(-)

(limited to 'server/src/datex2.cpp')

diff --git a/server/src/datex2.cpp b/server/src/datex2.cpp
index 4c8000b..70c5f94 100644
--- a/server/src/datex2.cpp
+++ b/server/src/datex2.cpp
@@ -51,32 +51,41 @@ auto loader::add_location_from_xml(
     }
     auto const pos_list_str =
         std::string_view{loc_gml_xml.child_value("loc:posList")};
-    // lat1 long1 lat2 long2 ... lat(n-1) long(n-1) latn longn
+    // lat1 lon1 lat2 lon2 ... lat(n-1) lon(n-1) latn lonn
 
-    auto ls = std::make_shared<geo::linestring>();
+    auto ls = std::make_shared<geo::utm::zonable_wgs84_linestring>();
 
     auto lat_set = false;
     auto lat = 0.0;
-    for (auto const lat_or_long_str : std::views::split(pos_list_str, " "sv))
+    for (auto const lat_or_lon_str : std::views::split(pos_list_str, " "sv))
     {
-      auto mlat_or_long = util::parse_double(std::string_view{lat_or_long_str});
-      if (!mlat_or_long)
+      auto mlat_or_lon = util::parse_double(std::string_view{lat_or_lon_str});
+      if (!mlat_or_lon)
       {
         warnings_.insert(
             std::format(
                 "failed to parse coordinate {:?}",
-                std::string_view{lat_or_long_str}));
+                std::string_view{lat_or_lon_str}));
         return;
       }
 
       if (!lat_set)
       {
-        lat = *mlat_or_long;
+        lat = *mlat_or_lon;
         lat_set = true;
       }
       else
       {
-        bgeo::append(*ls, geo::point{*mlat_or_long, lat});
+        auto mp = geo::utm::zonable_wgs84_point::from(
+            geo::wgs84::normalized_point{geo::wgs84::from_lat_lon(
+                lat, *mlat_or_lon)});
+        if (!mp)
+          warnings_.insert(
+              std::format(
+                  "point ({}, {}) outside of UTM range; ignoring it", lat,
+                  *mlat_or_lon));
+        else
+          bgeo::append(*ls, *mp);
         lat = 0;
         lat_set = false;
       }
@@ -110,11 +119,24 @@ auto loader::add_location_from_xml(
     // maar heeft het UML-model van DATEX II v3 het over ETRS 89:
     //   https://docs.datex2.eu/_static/data/v3.7/umlmodel/html/EARoot/EA3/EA3/EA5/EA676.htm
 
-    auto const coords_etrs89 = geo::point{*mlon, *mlat};
-    auto coords_wgs84 = geo::point{};
+    auto const coords_etrs89 = geo::wgs84::point{*mlon, *mlat};
+    auto coords_wgs84 = geo::wgs84::point{};
     etrs89_to_wgs84_.forward(coords_etrs89, coords_wgs84);
 
-    rc.relevant_points.push_back(coords_wgs84);
+    auto mp = geo::utm::zonable_wgs84_point::from(
+        geo::wgs84::normalized_point{coords_wgs84});
+    if (!mp)
+    {
+      warnings_.insert(
+          std::format(
+              "(ETRS89) point ({}, {}) outside of UTM range after "
+              "transformation to WGS 84; ignoring it",
+              *mlat, *mlon));
+    }
+    else
+    {
+      rc.relevant_points.push_back(*mp);
+    }
   }
   else
   {
@@ -347,13 +369,23 @@ auto loader::load_situation_publication(std::string const& filename)
                 // het over ETRS 89:
                 //   https://docs.datex2.eu/_static/data/v3.7/umlmodel/html/EARoot/EA3/EA3/EA5/EA676.htm
 
-                auto const coords_etrs89 = geo::point{*mlon, *mlat};
-                auto coords_wgs84 = geo::point{};
+                auto const coords_etrs89 = geo::wgs84::point{*mlon, *mlat};
+                auto coords_wgs84 = geo::wgs84::point{};
                 etrs89_to_wgs84_.forward(coords_etrs89, coords_wgs84);
 
-                if (!sit->location)
+                auto mp = geo::utm::zonable_wgs84_point::from(
+                    geo::wgs84::normalized_point{coords_wgs84});
+                if (!mp)
+                {
+                  warnings_.insert(
+                      std::format(
+                          "(ETRS89) point ({}, {}) outside of UTM range after "
+                          "transformation to WGS 84; ignoring it",
+                          *mlat, *mlon));
+                }
+                else if (!sit->location)
                 {
-                  sit->location = coords_wgs84;
+                  sit->location = *mp;
                 }
               }
             }
-- 
cgit v1.3