def test_reference_scale(self):
"""
Test rendering a layer with a reference scale set
"""
layer = QgsVectorLayer(os.path.join(TEST_DATA_DIR, 'lines.shp'), 'Lines', 'ogr')
self.assertTrue(layer.isValid())
sym1 = QgsLineSymbol.createSimple({'line_color': '#4dbf6f', 'line_width': 4, 'line_width_unit': "points"})
renderer = QgsSingleSymbolRenderer(sym1)
layer.setRenderer(renderer)
mapsettings = QgsMapSettings()
mapsettings.setDestinationCrs(layer.crs())
mapsettings.setOutputSize(QSize(400, 400))
mapsettings.setOutputDpi(96)
mapsettings.setExtent(layer.extent())
mapsettings.setLayers([layer])
self.assertAlmostEqual(mapsettings.scale(), 22738556, -5)
# Setup rendering check
renderchecker = QgsMultiRenderChecker()
renderchecker.setMapSettings(mapsettings)
renderchecker.setControlPathPrefix('vectorlayerrenderer')
renderchecker.setControlName('expected_reference_scale_not_set')
result = renderchecker.runTest('expected_reference_scale_not_set')
self.report += renderchecker.report()
self.assertTrue(result)
# Set the reference scale as half the map scale -- the lines should be double as wide
# as their preset width
renderer.setReferenceScale(22738556 * 2)
renderchecker = QgsMultiRenderChecker()
renderchecker.setMapSettings(mapsettings)
renderchecker.setControlPathPrefix('vectorlayerrenderer')
renderchecker.setControlName('expected_reference_scale_double')
result = renderchecker.runTest('expected_reference_scale_double')
self.report += renderchecker.report()
self.assertTrue(result)
# Set the reference scale as double the map scale -- the lines should be half as wide
# as their preset width
renderer.setReferenceScale(22738556 / 2)
renderchecker = QgsMultiRenderChecker()
renderchecker.setMapSettings(mapsettings)
renderchecker.setControlPathPrefix('vectorlayerrenderer')
renderchecker.setControlName('expected_reference_scale_half')
result = renderchecker.runTest('expected_reference_scale_half')
self.report += renderchecker.report()
self.assertTrue(result)
