Fix determination of geodesic line when first segment is small and co…

…ordinates are reprojected
qgis · Jan 16, 2019 · 1248bea · 1248bea
1 parent 4e6a730
commit 1248bea
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Showing 2 changed files with 6 additions and 2 deletions.
diff --git a/src/core/qgsdistancearea.cpp b/src/core/qgsdistancearea.cpp
@@ -700,8 +700,8 @@ QVector< QVector<QgsPointXY> > QgsDistanceArea::geodesicLine( const QgsPointXY &
   QVector< QgsPointXY > currentPart;
   currentPart << p1;
   double d = interval;
-  double prevLon = p1.x();
-  double prevLat = p1.y();
+  double prevLon = pp1.x();
+  double prevLat = pp1.y();
   bool lastRun = false;
   double t = 0;
   while ( true )

diff --git a/tests/src/python/test_qgsdistancearea.py b/tests/src/python/test_qgsdistancearea.py
@@ -791,6 +791,10 @@ def testGeodesicLine(self):
                                                             1000000, True))
         self.assertEqual(g.asWkt(0),
                          'MultiLineString ((-13536427 14138932, -16514348 11691516, -17948849 9406595, -18744235 7552985, -19255354 6014890, -19622372 4688888, -19909239 3505045, -20037508 2933522),(20037508 2933522, 19925702 2415579, 19712755 1385803, 19513769 388441, 19318507 -600065, 19117459 -1602293, 18899973 -2642347, 18651869 -3748726, 18351356 -4958346, 17960498 -6322823, 17404561 -7918366, 16514601 -9855937, 14851845 -12232940, 13760912 -13248201))')
+        g = QgsGeometry.fromMultiPolylineXY(da.geodesicLine(QgsPointXY(18933544, -5448034), QgsPointXY(-11638480, 3962206),
+                                                            1000000, True))
+        self.assertEqual(g.asWkt(0),
+                         'MultiLineString ((18933544 -5448034, 20037508 -4772933),(-20037508 -4772933, -20002064 -4748323, -19015781 -3988451, -18153035 -3204936, -17383137 -2416816, -16678635 -1632067, -16015884 -852355, -15374147 -76043, -14734258 699941, -14077193 1478790, -13382634 2262546, -12627598 3050380, -11785404 3835868, -11638480 3962206))')
 
     def testSplitGeometryAtAntimeridian(self):
         da = QgsDistanceArea()