Merge branch 'fix_force_lhr-rhr_268' into 'master'

ForceOrderPoints: fix interior ring order Closes #268 See merge request sfcgal/SFCGAL!324
Oslandia · Jul 12, 2024 · 543674d · 543674d
2 parents 81fdf79 + c2dcf4c
commit 543674d
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Showing 2 changed files with 47 additions and 10 deletions.
diff --git a/src/detail/transform/ForceOrderPoints.cpp b/src/detail/transform/ForceOrderPoints.cpp
@@ -62,18 +62,12 @@ ForceOrderPoints::visit(Polygon &p)
       }
     }
 
+    const bool isCCWO{algorithm::isCounterClockWiseOriented(ext)};
     for (size_t i = 0; i < p.numInteriorRings(); ++i) {
-      LineString inter = p.interiorRingN(i);
+      LineString &inter = p.interiorRingN(i);
 
-      if (algorithm::isCounterClockWiseOriented(inter)) {
-        // interior ring is pointing up, reverse
-        if (_orientCCW) {
-          inter.reverse();
-        }
-      } else {
-        if (!_orientCCW) {
-          inter.reverse();
-        }
+      if (algorithm::isCounterClockWiseOriented(inter) == isCCWO) {
+        inter.reverse();
       }
     }
 

diff --git a/test/unit/SFCGAL/capi/sfcgal_cTest.cpp b/test/unit/SFCGAL/capi/sfcgal_cTest.cpp
@@ -171,4 +171,47 @@ BOOST_AUTO_TEST_CASE(testLineSubstring)
 
   BOOST_CHECK(sfcgal_geometry_covers_3d(ls, g2.get()));
 }
+
+BOOST_AUTO_TEST_CASE(testForceRHR)
+{
+  sfcgal_set_error_handlers(printf, on_error);
+
+  std::string strGeom{"POLYGON((0 0,0 5,5 5,5 0,0 0),(1 1,2 1,2 2,1 2,1 1))"};
+
+  std::unique_ptr<Geometry> const geom(io::readWkt(strGeom));
+
+  sfcgal_geometry_t *rhr = sfcgal_geometry_force_rhr(geom.get());
+  // retrieve wkb from C api
+  char  *wkbApi;
+  size_t wkbLen;
+  sfcgal_geometry_as_text_decim(rhr, 0, &wkbApi, &wkbLen);
+  std::string strApi(wkbApi, wkbLen);
+
+  // check
+  BOOST_CHECK_EQUAL(strGeom, strApi);
+  delete[] wkbApi;
+}
+
+BOOST_AUTO_TEST_CASE(testForceLHR)
+{
+  sfcgal_set_error_handlers(printf, on_error);
+
+  std::string strGeom{"POLYGON((0 0,0 5,5 5,5 0,0 0),(1 1,2 1,2 2,1 2,1 1))"};
+  std::string expectedGeom{
+      "POLYGON((0 0,5 0,5 5,0 5,0 0),(1 1,1 2,2 2,2 1,1 1))"};
+
+  std::unique_ptr<Geometry> const geom(io::readWkt(strGeom));
+
+  sfcgal_geometry_t *lhr = sfcgal_geometry_force_lhr(geom.get());
+  // retrieve wkb from C api
+  char  *wkbApi;
+  size_t wkbLen;
+  sfcgal_geometry_as_text_decim(lhr, 0, &wkbApi, &wkbLen);
+  std::string strApi(wkbApi, wkbLen);
+
+  // check
+  BOOST_CHECK_EQUAL(expectedGeom, strApi);
+  delete[] wkbApi;
+}
+
 BOOST_AUTO_TEST_SUITE_END()