def postProcessLayer(self, layer, context, feedback):
_ = feedback, context
layer.setLabelsEnabled(True)
pal = QgsPalLayerSettings()
# Expression combinant les nom d'habitat et du faciès
pal.fieldName = "|| ' - ' || ".join(self.fields)
pal.isExpression = True
# Mais ce label est trop long
# utilisation du faciès pour le label
# et du nom pour le rendu
pal.fieldName = self.fields[1]
pal.isExpression = False
pal.labelPerPart = True
pal.placement = QgsPalLayerSettings.OverPoint
txt_buff = QgsTextBufferSettings()
txt_buff.setEnabled(True)
txt_format = pal.format()
txt_format.setBuffer(txt_buff)
pal.setFormat(txt_format)
layer.setLabeling(QgsVectorLayerSimpleLabeling(pal))
renderer = layer.renderer()
symbol = renderer.symbol()
symbol.setSize(6)
# Symbologie à partir du champs nom de l'habitat
index = layer.fields().indexOf(self.fields[0])
values = layer.uniqueValues(index)
color = QgsRandomColorRamp()
color.setTotalColorCount(len(values))
categories = []
for i, value in enumerate(values):
symbol = QgsSymbol.defaultSymbol(QgsWkbTypes.PointGeometry)
symbol.setColor(color.color(i))
symbol.setSize(5)
category = QgsRendererCategory(value, symbol, value)
categories.append(category)
renderer = QgsCategorizedSymbolRenderer(self.fields[0], categories)
layer.setRenderer(renderer)
layer.triggerRepaint()
def set_style(self):
""" Set the categorized style using random color. """
index = self.output_layer.fields().indexOf('nom')
values = self.output_layer.uniqueValues(index)
color = QgsRandomColorRamp()
color.setTotalColorCount(len(values))
categories = []
for i, value in enumerate(values):
symbol = QgsSymbol.defaultSymbol(QgsWkbTypes.PolygonGeometry)
symbol.setColor(color.color(i))
category = QgsRendererCategory(value, symbol, value)
categories.append(category)
renderer = QgsCategorizedSymbolRenderer('nom', categories)
self.output_layer.setRenderer(renderer)
def _test(is_sidecar):
QgsProject.instance().removeAllMapLayers()
tmp_dir = QTemporaryDir()
shutil.copy(os.path.join(os.path.dirname(
__file__), 'data', 'raster-palette.tif'), tmp_dir.path())
rat_path = os.path.join(
tmp_dir.path(), 'raster-palette.tif' + ('.vat.dbf' if is_sidecar else '.aux.xml'))
self.assertFalse(os.path.exists(rat_path))
raster_layer = QgsRasterLayer(os.path.join(tmp_dir.path(), 'raster-palette.tif'), 'rat_test', 'gdal')
QgsProject.instance().addMapLayer(raster_layer)
self.assertTrue(raster_layer.isValid())
self.assertFalse(can_create_rat(raster_layer))
self.assertFalse(has_rat(raster_layer))
band = 1
# Set renderer
ramp = QgsRandomColorRamp()
renderer = QgsPalettedRasterRenderer(
raster_layer.dataProvider(), 1, QgsPalettedRasterRenderer.classDataFromRaster(raster_layer.dataProvider(), band, ramp))
raster_layer.setRenderer(renderer)
self.assertTrue(can_create_rat(raster_layer))
rat = create_rat_from_raster(raster_layer, is_sidecar, rat_path)
self.assertTrue(rat.isValid())
self.assertEqual(rat.data['Count'], [78, 176, 52])
self.assertEqual(rat.data['Value'], [
2.257495271713565, 7.037407804695962, 270.4551067154352])
self.assertEqual(rat.data['A'], [255, 255, 255])
self.assertNotEqual(rat.data['R'], [0, 0, 0])
self.assertTrue(rat.save(band))
self.assertTrue(os.path.exists(rat_path))
QgsProject.instance().removeMapLayers([raster_layer.id()])
del (raster_layer)
self.assertTrue(os.path.exists(rat_path))
QgsApplication.processEvents()
# Reload and check
raster_layer = QgsRasterLayer(os.path.join(
tmp_dir.path(), 'raster-palette.tif'), 'rat_test', 'gdal')
self.assertTrue(raster_layer.isValid())
self.assertFalse(can_create_rat(raster_layer))
self.assertTrue(has_rat(raster_layer), rat_path)
os.unlink(rat_path)
def raster_apply_unique_value_renderer(raster_layer,
band_num=1,
n_decimals=0,
color_ramp='',
invert=False):
"""
Apply a random colour to each each unique value for a raster band.
In some case the unique values are floating, n_decimals allows these to be rounded for display
Args:
raster_layer (QgsRasterLayer): input raster layer
band_num (int): the band number used to determine unique values
n_decimals (int): number of decimals to round values to
invert (bool) : Invert the color ramp before applying - Not implemented
"""
qgsStyles = QgsStyle().defaultStyle()
# check to see if the colour ramp is installed
if color_ramp != '' and color_ramp not in qgsStyles.colorRampNames():
raise ValueError(
'PAT symbology does not exist. See user manual for install instructions'
)
if color_ramp == '':
ramp = QgsRandomColorRamp()
else:
# get an existing color ramp
ramp = qgsStyles.colorRamp(color_ramp)
# generate a list of unique values and their colours.
uniq_classes = QgsPalettedRasterRenderer.classDataFromRaster(
raster_layer.dataProvider(), band_num, ramp)
# Create the renderer
renderer = QgsPalettedRasterRenderer(raster_layer.dataProvider(), band_num,
uniq_classes)
# assign the renderer to the raster layer:
raster_layer.setRenderer(renderer)
# refresh
raster_layer.triggerRepaint()
def testQgsRandomColorRampV2(self):
# test random colors
r = QgsRandomColorRamp()
self.assertEqual(r.type(), 'randomcolors')
self.assertEqual(r.count(), -1) # no color count
self.assertEqual(r.value(0), 0) # all values should be 0
self.assertEqual(r.value(1), 0)
# test non-pregenerated colors. All should be valid
for i in range(10000):
c = r.color(0)
self.assertTrue(c.isValid())
# test creating from properties
# QgsRandomColorRamp has no properties for now, but test to ensure no crash
props = r.properties() # NOQA
# test cloning ramp
cloned = r.clone()
self.assertEqual(cloned.type(), 'randomcolors')
# test with pregenerated colors
for i in range(10000):
r.setTotalColorCount(10)
for j in range(10):
c = r.color(j * 0.1)
self.assertTrue(c.isValid())
def rat_classify(raster_layer, band, rat, criteria, ramp=None, feedback=QgsRasterBlockFeedback()) -> list:
"""Classify a raster.
Note: cannot use a custom shader function QgsColorRampShader subclass because it's lost in
the clone stage of the renderer.
:param raster_layer: the raster layer to classify
:type raster_layer: QgsRasterLayer
:param band: band number (1-based)
:type band: int
:param rat: the RAT data
:type rat: dict
:param criteria: key of the RAT to be used for labels
:type criteria: str
:param ramp: optional color ramp, defaults to QgsRandomColorRamp()
:type ramp: QgsColorRamp, optional
:param feedback: QGIS feedback object, defaults to QgsRasterBlockFeedback()
:type feedback: QgsRasterBlockFeedback, optional
:return: unique row indexes for legend items (1-based)
:rtype: list
"""
has_color = rat.has_color
labels = rat.data[criteria]
label_colors = {}
unique_indexes = []
# QGIS >= 3.18 for first element label
if Qgis.QGIS_VERSION_INT >= 31800:
base_legend_row_index = 1
else:
base_legend_row_index = 0
if rat.thematic_type == gdal.GRTT_THEMATIC:
# Use paletted
rat_log('Using paletted renderer')
value_column_name = rat.field_name(gdal.GFU_MinMax)
values = rat.data[value_column_name]
is_integer = isinstance(values[0], int)
if ramp is None:
ramp = QgsRandomColorRamp()
classes = QgsPalettedRasterRenderer.classDataFromRaster(
raster_layer.dataProvider(), band, ramp, feedback)
row_index = base_legend_row_index
for klass in classes:
value = int(klass.value) if is_integer else klass.value
try:
index = values.index(value)
except ValueError: # NODATA
rat_log(
f'Value {value} not found in RAT, assuming NODATA', Qgis.Warning)
data_provider = raster_layer.dataProvider()
if not data_provider.userNoDataValuesContains(band, value):
nodata = data_provider.userNoDataValues(band)
nodata_value = QgsRasterRange(value, value)
nodata.append(nodata_value)
data_provider.setUserNoDataValue(band, nodata)
continue
klass.label = str(labels[index])
if klass.label not in label_colors:
unique_indexes.append(row_index)
if has_color:
label_colors[klass.label] = rat.data[RAT_COLOR_HEADER_NAME][index]
else:
label_colors[klass.label] = klass.color
klass.color = label_colors[klass.label]
row_index += 1
renderer = QgsPalettedRasterRenderer(
raster_layer.dataProvider(), band, classes)
else: # ranges
rat_log('Using singleband pseudocolor renderer')
min_value_column = rat.field_name(gdal.GFU_Min)
max_value_column = rat.field_name(gdal.GFU_Max)
# Collect unique values and colors from criteria
row_index = base_legend_row_index
unique_labels = []
for index in range(len(labels)):
label = labels[index]
if label not in unique_labels:
unique_labels.append(label)
unique_indexes.append(row_index)
# Collect color
if has_color:
label_colors[label] = rat.data[RAT_COLOR_HEADER_NAME][index]
row_index += 1
# Assign colors from random ramp
if not has_color:
ramp = QgsRandomColorRamp()
ramp.setTotalColorCount(len(unique_labels))
i = 0
for index in unique_indexes:
label_colors[labels[index]] = ramp.color(ramp.value(i))
i += 1
# Create values for the ramp
# Collect colors for all classes
colors = []
for label in labels:
colors.append(label_colors[label])
ramp = QgsPresetSchemeColorRamp(colors)
minValue = min(rat.data[min_value_column])
maxValue = max(rat.data[max_value_column])
assert minValue < maxValue, "Min Value must be lower than Max Value"
shader = QgsRasterShader(minValue, maxValue)
colorRampShaderFcn = QgsColorRampShader(
minValue, maxValue, ramp)
colorRampShaderFcn.setClip(True)
colorRampShaderFcn.setColorRampType(QgsColorRampShader.Discrete)
items = []
row = 0
for label in labels:
items.append(QgsColorRampShader.ColorRampItem(
rat.data[max_value_column][row], label_colors[label], label))
row += 1
colorRampShaderFcn.setColorRampItemList(items)
try: # for older QGIS
colorRampShaderFcn.legendSettings().setUseContinuousLegend(False)
except AttributeError:
rat_log(
'QgsColorRampShader.legendSettings().setUseContinuousLegend() is not supported on ths QGIS version.', Qgis.Warning)
shader.setRasterShaderFunction(colorRampShaderFcn)
renderer = QgsSingleBandPseudoColorRenderer(
raster_layer.dataProvider(), band, shader)
raster_layer.setRenderer(renderer)
raster_layer.triggerRepaint()
return unique_indexes
