def testTrueNorth(self):
""" test calculating bearing to true north"""
# short circuit - already a geographic crs
crs = QgsCoordinateReferenceSystem.fromEpsgId(4326)
transformContext = QgsCoordinateTransformContext()
self.assertEqual(QgsBearingUtils.bearingTrueNorth(crs, transformContext, QgsPointXY(0, 0)), 0)
self.assertEqual(QgsBearingUtils.bearingTrueNorth(crs, transformContext, QgsPointXY(44, 0)), 0)
self.assertEqual(QgsBearingUtils.bearingTrueNorth(crs, transformContext, QgsPointXY(44, -43)), 0)
self.assertEqual(QgsBearingUtils.bearingTrueNorth(crs, transformContext, QgsPointXY(44, 43)), 0)
self.assertEqual(QgsBearingUtils.bearingTrueNorth(crs, transformContext, QgsPointXY(44, 200)), 0)
self.assertEqual(QgsBearingUtils.bearingTrueNorth(crs, transformContext, QgsPointXY(44, -200)), 0)
# no short circuit
crs = QgsCoordinateReferenceSystem.fromEpsgId(3111)
self.assertAlmostEqual(QgsBearingUtils.bearingTrueNorth(crs, transformContext, QgsPointXY(2508807, 2423425)), 0.06, 2)
# try a south-up crs
crs = QgsCoordinateReferenceSystem.fromEpsgId(2053)
self.assertAlmostEqual(QgsBearingUtils.bearingTrueNorth(crs, transformContext, QgsPointXY(29, -27.55)), -180.0, 1)
# try a north pole crs
crs = QgsCoordinateReferenceSystem.fromEpsgId(3575)
self.assertAlmostEqual(QgsBearingUtils.bearingTrueNorth(crs, transformContext, QgsPointXY(-780770, 652329)), 129.9, 1)
self.assertAlmostEqual(QgsBearingUtils.bearingTrueNorth(crs, transformContext, QgsPointXY(513480, 873173)), -149.5, 1)
def testTrueNorth(self):
""" test calculating bearing to true north"""
# short circuit - already a geographic crs
crs = QgsCoordinateReferenceSystem.fromEpsgId(4326)
self.assertEqual(QgsBearingUtils.bearingTrueNorth(crs, QgsPoint(0, 0)), 0)
self.assertEqual(QgsBearingUtils.bearingTrueNorth(crs, QgsPoint(44, 0)), 0)
self.assertEqual(QgsBearingUtils.bearingTrueNorth(crs, QgsPoint(44, -43)), 0)
self.assertEqual(QgsBearingUtils.bearingTrueNorth(crs, QgsPoint(44, 43)), 0)
self.assertEqual(QgsBearingUtils.bearingTrueNorth(crs, QgsPoint(44, 200)), 0)
self.assertEqual(QgsBearingUtils.bearingTrueNorth(crs, QgsPoint(44, -200)), 0)
# no short circuit
crs = QgsCoordinateReferenceSystem.fromEpsgId(3111)
self.assertAlmostEqual(QgsBearingUtils.bearingTrueNorth(crs, QgsPoint(2508807, 2423425)), 0.06, 2)
# try a south-up crs
crs = QgsCoordinateReferenceSystem.fromEpsgId(2053)
self.assertAlmostEqual(QgsBearingUtils.bearingTrueNorth(crs, QgsPoint(29, -27.55)), -180.0, 1)
# try a north pole crs
crs = QgsCoordinateReferenceSystem.fromEpsgId(3575)
self.assertAlmostEqual(QgsBearingUtils.bearingTrueNorth(crs, QgsPoint(-780770, 652329)), 129.9, 1)
self.assertAlmostEqual(QgsBearingUtils.bearingTrueNorth(crs, QgsPoint(513480, 873173)), -149.5, 1)
def paint(self, painter, xxx, xxx2):
"""Paint north arrow on painter"""
if self.svg.isValid():
pos = self.set_position(self.corner,
painter.device().width(),
painter.device().height())
rotation = QgsBearingUtils.bearingTrueNorth(
self.canvas.mapSettings().destinationCrs(),
self.canvas.mapSettings().transformContext(),
self.canvas.extent().center())
rotation += self.canvas.rotation()
painter.save()
painter.rotate(-rotation) # To translate correctly
painter.translate(pos.x(), pos.y())
painter.rotate(
rotation
) # To rotate north arrow along with canvas, always pointing north
# do the drawing, and draw a smooth north arrow even when rotated
rectangle = QRectF(-self.size.width() / 2, -self.size.height() / 2,
self.size.width(), self.size.height())
self.svg.render(painter, rectangle)
painter.restore()