Use QgsAbstractGeometry methods for QgsGeometry::area results

Use the QgsAbstractGeometry method, so that consistent results are obtained across the API and an exact length is used for curved geometries (instead of the length of the segmentized curves)
qgis · Nov 2, 2021 · d787754 · d787754
1 parent 4b7dff6
commit d787754
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Showing 2 changed files with 12 additions and 14 deletions.
diff --git a/src/core/geometry/qgsgeometry.cpp b/src/core/geometry/qgsgeometry.cpp
@@ -1889,21 +1889,8 @@ double QgsGeometry::area() const
   {
     return -1.0;
   }
-  QgsGeos g( d->geometry.get() );
-
-#if 0
-  //debug: compare geos area with calculation in QGIS
-  double geosArea = g.area();
-  double qgisArea = 0;
-  QgsSurface *surface = qgsgeometry_cast<QgsSurface *>( d->geometry );
-  if ( surface )
-  {
-    qgisArea = surface->area();
-  }
-#endif
 
-  mLastError.clear();
-  return g.area( &mLastError );
+  return d->geometry->area();
 }
 
 double QgsGeometry::length() const

diff --git a/tests/src/python/test_qgsgeometry.py b/tests/src/python/test_qgsgeometry.py
@@ -931,18 +931,29 @@ def testReferenceGeometry(self):
                 result = geom.constGet().area()
                 self.assertAlmostEqual(result, exp, 5,
                                        "Area {}: mismatch Expected:\n{}\nGot:\n{}\n".format(i + 1, exp, result))
+                result = geom.area()
+                self.assertAlmostEqual(result, exp, 5,
+                                       "Length {}: mismatch Expected:\n{}\nGot:\n{}\n".format(i + 1, exp, result))
 
                 # test length calculation
                 exp = float(row['length'])
                 result = geom.constGet().length()
                 self.assertAlmostEqual(result, exp, 5,
                                        "Length {}: mismatch Expected:\n{}\nGot:\n{}\n".format(i + 1, exp, result))
+                if geom.type() != QgsWkbTypes.PolygonGeometry:
+                    result = geom.length()
+                    self.assertAlmostEqual(result, exp, 5,
+                                           "Length {}: mismatch Expected:\n{}\nGot:\n{}\n".format(i + 1, exp, result))
 
                 # test perimeter calculation
                 exp = float(row['perimeter'])
                 result = geom.constGet().perimeter()
                 self.assertAlmostEqual(result, exp, 5,
                                        "Perimeter {}: mismatch Expected:\n{}\nGot:\n{}\n".format(i + 1, exp, result))
+                if geom.type() == QgsWkbTypes.PolygonGeometry:
+                    result = geom.length()
+                    self.assertAlmostEqual(result, exp, 5,
+                                           "Length {}: mismatch Expected:\n{}\nGot:\n{}\n".format(i + 1, exp, result))
 
     def testCollection(self):
         g = QgsGeometry.fromWkt('MultiLineString EMPTY')