Merge pull request #1629 from joto/fix-proj6-projection

lonvia · web-flow · commit 02d7d7de0973 · 2022-02-01T15:05:38.000+01:00
Fix reprojection when using Proj version 6 and above
diff --git a/src/reprojection-generic-proj6.cpp b/src/reprojection-generic-proj6.cpp
@@ -15,22 +15,10 @@ class generic_reprojection_t : public reprojection
 {
 public:
     explicit generic_reprojection_t(int srs)
-    : m_target_srs(srs), m_context(proj_context_create())
-    {
-        assert(m_context);
-
-        m_transformation = create_transformation(PROJ_LATLONG, srs);
-
-        m_transformation.reset(proj_normalize_for_visualization(
-            m_context.get(), m_transformation.get()));
-
-        if (!m_transformation) {
-            throw std::runtime_error{
-                "Invalid projection '{}': {}"_format(srs, errormsg())};
-        }
-
-        m_transformation_tile = create_transformation(PROJ_SPHERE_MERC, srs);
-    }
+    : m_target_srs(srs), m_context(proj_context_create()),
+      m_transformation(create_transformation(PROJ_LATLONG, srs)),
+      m_transformation_tile(create_transformation(srs, PROJ_SPHERE_MERC))
+    {}
 
     osmium::geom::Coordinates reproject(osmium::Location loc) const override
     {
@@ -71,6 +59,8 @@ class generic_reprojection_t : public reprojection
     std::unique_ptr<PJ, pj_deleter_t> create_transformation(int from,
                                                             int to) const
     {
+        assert(m_context);
+
         std::string const source = "epsg:{}"_format(from);
         std::string const target = "epsg:{}"_format(to);
 
@@ -82,7 +72,17 @@ class generic_reprojection_t : public reprojection
                 "Invalid projection from {} to {}: {}"_format(from, to,
                                                               errormsg())};
         }
-        return trans;
+
+        std::unique_ptr<PJ, pj_deleter_t> trans_vis{
+            proj_normalize_for_visualization(m_context.get(), trans.get())};
+
+        if (!trans_vis) {
+            throw std::runtime_error{
+                "Invalid projection from {} to {}: {}"_format(from, to,
+                                                              errormsg())};
+        }
+
+        return trans_vis;
     }
 
     osmium::geom::Coordinates transform(PJ *transformation,
@@ -92,8 +92,8 @@ class generic_reprojection_t : public reprojection
         PJ_COORD c_in;
         c_in.lpzt.z = 0.0;
         c_in.lpzt.t = HUGE_VAL;
-        c_in.lpzt.lam = osmium::geom::deg_to_rad(coords.x);
-        c_in.lpzt.phi = osmium::geom::deg_to_rad(coords.y);
+        c_in.lpzt.lam = coords.x;
+        c_in.lpzt.phi = coords.y;
 
         auto const c_out = proj_trans(transformation, PJ_FWD, c_in);
 
diff --git a/tests/test-reprojection.cpp b/tests/test-reprojection.cpp
@@ -9,6 +9,7 @@
 
 #include <catch.hpp>
 
+#include "config.h"
 #include "reprojection.hpp"
 
 TEST_CASE("projection 4326", "[NoDB]")
@@ -48,18 +49,18 @@ TEST_CASE("projection 3857", "[NoDB]")
 }
 
 #ifdef HAVE_GENERIC_PROJ
-TEST_CASE("projection 5520", "[NoDB]")
+TEST_CASE("projection 5651", "[NoDB]")
 {
     osmium::Location const loc{10.0, 53.0};
-    int const srs = 5520; // DHDN / 3-degree Gauss-Kruger zone 1
+    int const srs = 5651; // ETRS89 / UTM zone 31N (N-zE)
 
     auto const reprojection = reprojection::create_projection(srs);
     REQUIRE(reprojection->target_srs() == srs);
     REQUIRE_FALSE(reprojection->target_latlon());
 
     auto const c = reprojection->reproject(loc);
-    REQUIRE(c.x == Approx(1969644.93));
-    REQUIRE(c.y == Approx(5897146.04));
+    REQUIRE(c.x == Approx(31969448.78));
+    REQUIRE(c.y == Approx(5895222.39));
 
     auto const ct = reprojection->target_to_tile(c);
     REQUIRE(ct.x == Approx(1113194.91));
