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"Fix" QgsDistanceArea test on OSX

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Test has revealed that the current algorithm used for ellipsoidal
calculations is unstable when measuring small very areas (eg < 1m2)

For now, modify the test to use larger areas
This commit is contained in:
Nyall Dawson 2016-02-16 12:09:16 +11:00
parent f8d2091255
commit 2265eb90ec
3 changed files with 104 additions and 5 deletions

2
ci/travis/osx/script.sh

@ -1,2 +1,2 @@
ctest -V -E 'qgis_openstreetmaptest|qgis_wcsprovidertest|PyQgsServer|PyQgsDistanceArea' -S ./qgis-test-travis.ctest --output-on-failure
ctest -V -E 'qgis_openstreetmaptest|qgis_wcsprovidertest|PyQgsServer' -S ./qgis-test-travis.ctest --output-on-failure

94
tests/src/core/testqgsdistancearea.cpp

@ -41,6 +41,8 @@ class TestQgsDistanceArea: public QObject
void regression13601();
void collections();
void measureUnits();
void measureAreaAndUnits();
};
void TestQgsDistanceArea::initTestCase()
@ -250,6 +252,98 @@ void TestQgsDistanceArea::measureUnits()
QVERIFY( qgsDoubleNear( result, 2328.0988253106957, 0.001 ) );
}
void TestQgsDistanceArea::measureAreaAndUnits()
{
QgsDistanceArea da;
da.setSourceCrs( 3452 );
da.setEllipsoidalMode( false );
da.setEllipsoid( "NONE" );
QgsCoordinateReferenceSystem daCRS;
daCRS.createFromSrsId( da.sourceCrsId() );
QgsPolyline ring;
ring << QgsPoint( 0, 0 )
<< QgsPoint( 1, 0 )
<< QgsPoint( 1, 1 )
<< QgsPoint( 2, 1 )
<< QgsPoint( 2, 2 )
<< QgsPoint( 0, 2 )
<< QgsPoint( 0, 0 );
QgsPolygon poly;
poly << ring;
QScopedPointer< QgsGeometry > polygon( QgsGeometry::fromPolygon( poly ) );
// We check both the measured area AND the units, in case the logic regarding
// ellipsoids and units changes in future
double area = da.measureArea( polygon.data() );
QgsUnitTypes::AreaUnit units = da.areaUnits();
QgsDebugMsg( QString( "measured %1 in %2" ).arg( area ).arg( QgsUnitTypes::toString( units ) ) );
QVERIFY(( qgsDoubleNear( area, 3.0, 0.00000001 ) && units == QgsUnitTypes::SquareDegrees )
|| ( qgsDoubleNear( area, 37176087091.5, 0.1 ) && units == QgsUnitTypes::SquareMeters ) );
da.setEllipsoid( "WGS84" );
area = da.measureArea( polygon.data() );
units = da.areaUnits();
QgsDebugMsg( QString( "measured %1 in %2" ).arg( area ).arg( QgsUnitTypes::toString( units ) ) );
QVERIFY(( qgsDoubleNear( area, 3.0, 0.00000001 ) && units == QgsUnitTypes::SquareDegrees )
|| ( qgsDoubleNear( area, 37176087091.5, 0.1 ) && units == QgsUnitTypes::SquareMeters ) );
da.setEllipsoidalMode( true );
area = da.measureArea( polygon.data() );
units = da.areaUnits();
QgsDebugMsg( QString( "measured %1 in %2" ).arg( area ).arg( QgsUnitTypes::toString( units ) ) );
// should always be in Meters Squared
QVERIFY( qgsDoubleNear( area, 37416879192.9, 0.1 ) );
QCOMPARE( units, QgsUnitTypes::SquareMeters );
// test converting the resultant area
area = da.convertAreaMeasurement( area, QgsUnitTypes::SquareMiles );
QVERIFY( qgsDoubleNear( area, 14446.7378, 0.001 ) );
// now try with a source CRS which is in feet
ring.clear();
ring << QgsPoint( 1850000, 4423000 )
<< QgsPoint( 1851000, 4423000 )
<< QgsPoint( 1851000, 4424000 )
<< QgsPoint( 1852000, 4424000 )
<< QgsPoint( 1852000, 4425000 )
<< QgsPoint( 1851000, 4425000 )
<< QgsPoint( 1850000, 4423000 );
poly.clear();
poly << ring;
polygon.reset( QgsGeometry::fromPolygon( poly ) );
da.setSourceCrs( 27469 );
da.setEllipsoidalMode( false );
// measurement should be in square feet
area = da.measureArea( polygon.data() );
units = da.areaUnits();
QgsDebugMsg( QString( "measured %1 in %2" ).arg( area ).arg( QgsUnitTypes::toString( units ) ) );
QVERIFY( qgsDoubleNear( area, 2000000, 0.001 ) );
QCOMPARE( units, QgsUnitTypes::SquareFeet );
// test converting the resultant area
area = da.convertAreaMeasurement( area, QgsUnitTypes::SquareYards );
QVERIFY( qgsDoubleNear( area, 222222.2222, 0.001 ) );
da.setEllipsoidalMode( true );
// now should be in Square Meters again
area = da.measureArea( polygon.data() );
units = da.areaUnits();
QgsDebugMsg( QString( "measured %1 in %2" ).arg( area ).arg( QgsUnitTypes::toString( units ) ) );
QVERIFY( qgsDoubleNear( area, 184149.37309564, 0.00001 ) );
QCOMPARE( units, QgsUnitTypes::SquareMeters );
// test converting the resultant area
area = da.convertAreaMeasurement( area, QgsUnitTypes::SquareYards );
QgsDebugMsg( QString( "measured %1 in sq yrds" ).arg( area ) );
QVERIFY( qgsDoubleNear( area, 220240.8172549, 0.00001 ) );
}
QTEST_MAIN( TestQgsDistanceArea )
#include "testqgsdistancearea.moc"

13
tests/src/python/test_qgsdistancearea.py

@ -270,30 +270,35 @@ class TestQgsDistanceArea(unittest.TestCase):
self.assertAlmostEqual(area, 14446.7378, delta=0.001)
# now try with a source CRS which is in feet
polygon = QgsGeometry.fromPolygon(
[[
QgsPoint(1850000, 4423000), QgsPoint(1851000, 4423000), QgsPoint(1851000, 4424000), QgsPoint(1852000, 4424000), QgsPoint(1852000, 4425000), QgsPoint(1851000, 4425000), QgsPoint(1850000, 4423000)
]]
)
da.setSourceCrs(27469)
da.setEllipsoidalMode(False)
# measurement should be in square feet
area = da.measureArea(polygon)
units = da.areaUnits()
print "measured {} in {}".format(area, QgsUnitTypes.toString(units))
self.assertAlmostEqual(area, 3.0, delta=0.000001)
self.assertAlmostEqual(area, 2000000, delta=0.001)
self.assertEqual(units, QgsUnitTypes.SquareFeet)
# test converting the resultant area
area = da.convertAreaMeasurement(area, QgsUnitTypes.SquareYards)
self.assertAlmostEqual(area, 0.333333, delta=0.001)
self.assertAlmostEqual(area, 222222.2222, delta=0.001)
da.setEllipsoidalMode(True)
# now should be in Square Meters again
area = da.measureArea(polygon)
units = da.areaUnits()
print "measured {} in {}".format(area, QgsUnitTypes.toString(units))
self.assertAlmostEqual(area, 0.256102704082, delta=0.000001)
self.assertAlmostEqual(area, 184149.37309564, delta=0.000001)
self.assertEqual(units, QgsUnitTypes.SquareMeters)
# test converting the resultant area
area = da.convertAreaMeasurement(area, QgsUnitTypes.SquareYards)
self.assertAlmostEqual(area, 0.30629, delta=0.0001)
self.assertAlmostEqual(area, 220240.8172549, delta=0.0001)
if __name__ == '__main__':
unittest.main()