def fetch_values_from_layer(self): # pylint: disable=too-many-locals, too-many-branches, too-many-statements
"""
(Re)fetches plot values from the source layer.
"""
# Note: we keep things nice and efficient and only iterate a single time over the layer!
if not self.context_generator:
context = QgsExpressionContext()
context.appendScopes(
QgsExpressionContextUtils.globalProjectLayerScopes(
self.source_layer))
else:
context = self.context_generator.createExpressionContext()
# add a new scope corresponding to the source layer -- this will potentially overwrite any other
# layer scopes which may be present in the context (e.g. from atlas layers), but we need to ensure
# that source layer fields and attributes are present in the context
context.appendScope(
self.source_layer.createExpressionContextScope())
self.settings.data_defined_properties.prepare(context)
self.fetch_layout_properties(context)
def add_source_field_or_expression(field_or_expression):
field_index = self.source_layer.fields().lookupField(
field_or_expression)
if field_index == -1:
expression = QgsExpression(field_or_expression)
if not expression.hasParserError():
expression.prepare(context)
return expression, expression.needsGeometry(
), expression.referencedColumns()
return None, False, {field_or_expression}
x_expression, x_needs_geom, x_attrs = add_source_field_or_expression(self.settings.properties['x_name']) if \
self.settings.properties[
'x_name'] else (None, False, set())
y_expression, y_needs_geom, y_attrs = add_source_field_or_expression(self.settings.properties['y_name']) if \
self.settings.properties[
'y_name'] else (None, False, set())
z_expression, z_needs_geom, z_attrs = add_source_field_or_expression(self.settings.properties['z_name']) if \
self.settings.properties[
'z_name'] else (None, False, set())
additional_info_expression, additional_needs_geom, additional_attrs = add_source_field_or_expression(
self.settings.layout['additional_info_expression']
) if self.settings.layout['additional_info_expression'] else (None,
False,
set())
attrs = set().union(
self.settings.data_defined_properties.referencedFields(), x_attrs,
y_attrs, z_attrs, additional_attrs)
request = QgsFeatureRequest()
if self.settings.data_defined_properties.property(
PlotSettings.PROPERTY_FILTER).isActive():
expression = self.settings.data_defined_properties.property(
PlotSettings.PROPERTY_FILTER).asExpression()
request.setFilterExpression(expression)
request.setExpressionContext(context)
request.setSubsetOfAttributes(attrs, self.source_layer.fields())
if not x_needs_geom and not y_needs_geom and not z_needs_geom and not additional_needs_geom and not self.settings.data_defined_properties.hasActiveProperties(
):
request.setFlags(QgsFeatureRequest.NoGeometry)
visible_geom_engine = None
if self.visible_features_only and self.visible_region is not None:
ct = QgsCoordinateTransform(
self.visible_region.crs(), self.source_layer.crs(),
QgsProject.instance().transformContext())
try:
rect = ct.transformBoundingBox(self.visible_region)
request.setFilterRect(rect)
except QgsCsException:
pass
elif self.visible_features_only and self.polygon_filter is not None:
ct = QgsCoordinateTransform(
self.polygon_filter.crs(), self.source_layer.crs(),
QgsProject.instance().transformContext())
try:
rect = ct.transformBoundingBox(
self.polygon_filter.geometry.boundingBox())
request.setFilterRect(rect)
g = self.polygon_filter.geometry
g.transform(ct)
visible_geom_engine = QgsGeometry.createGeometryEngine(
g.constGet())
visible_geom_engine.prepareGeometry()
except QgsCsException:
pass
if self.selected_features_only:
it = self.source_layer.getSelectedFeatures(request)
else:
it = self.source_layer.getFeatures(request)
# Some plot types don't draw individual glyphs for each feature, but aggregate them instead.
# In that case it doesn't make sense to evaluate expressions for settings like marker size or color for each
# feature. Instead, the evaluation should be executed only once for these settings.
aggregating = self.settings.plot_type in ['box', 'histogram']
executed = False
xx = []
yy = []
zz = []
additional_hover_text = []
marker_sizes = []
colors = []
stroke_colors = []
stroke_widths = []
for f in it:
if visible_geom_engine and not visible_geom_engine.intersects(
f.geometry().constGet()):
continue
self.settings.feature_ids.append(f.id())
context.setFeature(f)
x = None
if x_expression:
x = x_expression.evaluate(context)
if x == NULL or x is None:
continue
elif self.settings.properties['x_name']:
x = f[self.settings.properties['x_name']]
if x == NULL or x is None:
continue
y = None
if y_expression:
y = y_expression.evaluate(context)
if y == NULL or y is None:
continue
elif self.settings.properties['y_name']:
y = f[self.settings.properties['y_name']]
if y == NULL or y is None:
continue
z = None
if z_expression:
z = z_expression.evaluate(context)
if z == NULL or z is None:
continue
elif self.settings.properties['z_name']:
z = f[self.settings.properties['z_name']]
if z == NULL or z is None:
continue
if additional_info_expression:
additional_hover_text.append(
additional_info_expression.evaluate(context))
elif self.settings.layout['additional_info_expression']:
additional_hover_text.append(
f[self.settings.layout['additional_info_expression']])
if x is not None:
xx.append(x)
if y is not None:
yy.append(y)
if z is not None:
zz.append(z)
if self.settings.data_defined_properties.isActive(
PlotSettings.PROPERTY_MARKER_SIZE):
default_value = self.settings.properties['marker_size']
context.setOriginalValueVariable(default_value)
value, _ = self.settings.data_defined_properties.valueAsDouble(
PlotSettings.PROPERTY_MARKER_SIZE, context, default_value)
marker_sizes.append(value)
if self.settings.data_defined_properties.isActive(
PlotSettings.PROPERTY_STROKE_WIDTH):
default_value = self.settings.properties['marker_width']
context.setOriginalValueVariable(default_value)
value, _ = self.settings.data_defined_properties.valueAsDouble(
PlotSettings.PROPERTY_STROKE_WIDTH, context, default_value)
stroke_widths.append(value)
if self.settings.data_defined_properties.isActive(
PlotSettings.PROPERTY_COLOR) and (not aggregating
or not executed):
default_value = QColor(self.settings.properties['in_color'])
value, conversion_success = self.settings.data_defined_properties.valueAsColor(
PlotSettings.PROPERTY_COLOR, context, default_value)
if conversion_success:
# We were given a valid color specification, use that color
colors.append(value.name())
else:
try:
# Attempt to interpret the value as a list of color specifications
value_list = self.settings.data_defined_properties.value(
PlotSettings.PROPERTY_COLOR, context)
color_list = [
QgsSymbolLayerUtils.decodeColor(item).name()
for item in value_list
]
colors.extend(color_list)
except TypeError:
# Not a list of color specifications, use the default color instead
colors.append(default_value.name())
if self.settings.data_defined_properties.isActive(
PlotSettings.PROPERTY_STROKE_COLOR) and (not aggregating
or not executed):
default_value = QColor(self.settings.properties['out_color'])
value, conversion_success = self.settings.data_defined_properties.valueAsColor(
PlotSettings.PROPERTY_STROKE_COLOR, context, default_value)
if conversion_success:
# We were given a valid color specification, use that color
stroke_colors.append(value.name())
else:
try:
# Attempt to interpret the value as a list of color specifications
value_list = self.settings.data_defined_properties.value(
PlotSettings.PROPERTY_STROKE_COLOR, context)
color_list = [
QgsSymbolLayerUtils.decodeColor(item).name()
for item in value_list
]
stroke_colors.extend(color_list)
except TypeError:
# Not a list of color specifications, use the default color instead
stroke_colors.append(default_value.name())
executed = True
self.settings.additional_hover_text = additional_hover_text
self.settings.x = xx
self.settings.y = yy
self.settings.z = zz
if marker_sizes:
self.settings.data_defined_marker_sizes = marker_sizes
if colors:
self.settings.data_defined_colors = colors
if stroke_colors:
self.settings.data_defined_stroke_colors = stroke_colors
if stroke_widths:
self.settings.data_defined_stroke_widths = stroke_widths
def fetch_values_from_layer(self): # pylint: disable=too-many-locals, too-many-branches, too-many-statements
"""
(Re)fetches plot values from the source layer.
"""
# Note: we keep things nice and efficient and only iterate a single time over the layer!
if not self.context_generator:
context = QgsExpressionContext()
context.appendScopes(
QgsExpressionContextUtils.globalProjectLayerScopes(
self.source_layer))
else:
context = self.context_generator.createExpressionContext()
self.settings.data_defined_properties.prepare(context)
def add_source_field_or_expression(field_or_expression):
field_index = self.source_layer.fields().lookupField(
field_or_expression)
if field_index == -1:
expression = QgsExpression(field_or_expression)
if not expression.hasParserError():
expression.prepare(context)
return expression, expression.needsGeometry(
), expression.referencedColumns()
return None, False, {field_or_expression}
x_expression, x_needs_geom, x_attrs = add_source_field_or_expression(self.settings.properties['x_name']) if \
self.settings.properties[
'x_name'] else (None, False, set())
y_expression, y_needs_geom, y_attrs = add_source_field_or_expression(self.settings.properties['y_name']) if \
self.settings.properties[
'y_name'] else (None, False, set())
z_expression, z_needs_geom, z_attrs = add_source_field_or_expression(self.settings.properties['z_name']) if \
self.settings.properties[
'z_name'] else (None, False, set())
additional_info_expression, additional_needs_geom, additional_attrs = add_source_field_or_expression(
self.settings.layout['additional_info_expression']
) if self.settings.layout['additional_info_expression'] else (None,
False,
set())
attrs = set().union(
self.settings.data_defined_properties.referencedFields(), x_attrs,
y_attrs, z_attrs, additional_attrs)
request = QgsFeatureRequest()
if self.settings.data_defined_properties.property(
PlotSettings.PROPERTY_FILTER).isActive():
expression = self.settings.data_defined_properties.property(
PlotSettings.PROPERTY_FILTER).asExpression()
request.setFilterExpression(expression)
request.setExpressionContext(context)
request.setSubsetOfAttributes(attrs, self.source_layer.fields())
if not x_needs_geom and not y_needs_geom and not z_needs_geom and not additional_needs_geom and not self.settings.data_defined_properties.hasActiveProperties(
):
request.setFlags(QgsFeatureRequest.NoGeometry)
visible_geom_engine = None
if self.visible_features_only and self.visible_region is not None:
ct = QgsCoordinateTransform(
self.visible_region.crs(), self.source_layer.crs(),
QgsProject.instance().transformContext())
try:
rect = ct.transformBoundingBox(self.visible_region)
request.setFilterRect(rect)
except QgsCsException:
pass
elif self.visible_features_only and self.polygon_filter is not None:
ct = QgsCoordinateTransform(
self.polygon_filter.crs(), self.source_layer.crs(),
QgsProject.instance().transformContext())
try:
rect = ct.transformBoundingBox(
self.polygon_filter.geometry.boundingBox())
request.setFilterRect(rect)
g = self.polygon_filter.geometry
g.transform(ct)
visible_geom_engine = QgsGeometry.createGeometryEngine(
g.constGet())
visible_geom_engine.prepareGeometry()
except QgsCsException:
pass
if self.selected_features_only:
it = self.source_layer.getSelectedFeatures(request)
else:
it = self.source_layer.getFeatures(request)
xx = []
yy = []
zz = []
additional_hover_text = []
marker_sizes = []
colors = []
stroke_colors = []
stroke_widths = []
for f in it:
if visible_geom_engine and not visible_geom_engine.intersects(
f.geometry().constGet()):
continue
self.settings.feature_ids.append(f.id())
context.setFeature(f)
x = None
if x_expression:
x = x_expression.evaluate(context)
if x == NULL or x is None:
continue
elif self.settings.properties['x_name']:
x = f[self.settings.properties['x_name']]
if x == NULL or x is None:
continue
y = None
if y_expression:
y = y_expression.evaluate(context)
if y == NULL or y is None:
continue
elif self.settings.properties['y_name']:
y = f[self.settings.properties['y_name']]
if y == NULL or y is None:
continue
z = None
if z_expression:
z = z_expression.evaluate(context)
if z == NULL or z is None:
continue
elif self.settings.properties['z_name']:
z = f[self.settings.properties['z_name']]
if z == NULL or z is None:
continue
if additional_info_expression:
additional_hover_text.append(
additional_info_expression.evaluate(context))
elif self.settings.layout['additional_info_expression']:
additional_hover_text.append(
f[self.settings.layout['additional_info_expression']])
if x is not None:
xx.append(x)
if y is not None:
yy.append(y)
if z is not None:
zz.append(z)
if self.settings.data_defined_properties.isActive(
PlotSettings.PROPERTY_MARKER_SIZE):
default_value = self.settings.properties['marker_size']
context.setOriginalValueVariable(default_value)
value, _ = self.settings.data_defined_properties.valueAsDouble(
PlotSettings.PROPERTY_MARKER_SIZE, context, default_value)
marker_sizes.append(value)
if self.settings.data_defined_properties.isActive(
PlotSettings.PROPERTY_STROKE_WIDTH):
default_value = self.settings.properties['marker_width']
context.setOriginalValueVariable(default_value)
value, _ = self.settings.data_defined_properties.valueAsDouble(
PlotSettings.PROPERTY_STROKE_WIDTH, context, default_value)
stroke_widths.append(value)
if self.settings.data_defined_properties.isActive(
PlotSettings.PROPERTY_COLOR):
default_value = QColor(self.settings.properties['in_color'])
value, _ = self.settings.data_defined_properties.valueAsColor(
PlotSettings.PROPERTY_COLOR, context, default_value)
colors.append(value.name())
if self.settings.data_defined_properties.isActive(
PlotSettings.PROPERTY_STROKE_COLOR):
default_value = QColor(self.settings.properties['out_color'])
value, _ = self.settings.data_defined_properties.valueAsColor(
PlotSettings.PROPERTY_STROKE_COLOR, context, default_value)
stroke_colors.append(value.name())
self.settings.additional_hover_text = additional_hover_text
self.settings.x = xx
self.settings.y = yy
self.settings.z = zz
if marker_sizes:
self.settings.data_defined_marker_sizes = marker_sizes
if colors:
self.settings.data_defined_colors = colors
if stroke_colors:
self.settings.data_defined_stroke_colors = stroke_colors
if stroke_widths:
self.settings.data_defined_stroke_widths = stroke_widths
