class CentroidDecorator(QgsMapCanvasItem):
"""
Decorates centroids of features with population statistics
"""
def __init__(self, canvas: QgsMapCanvas, electorate_layer: QgsVectorLayer,
meshblock_layer: QgsVectorLayer, task: str):
"""
Constructor
:param canvas: map canvas
:param electorate_layer: electorates layer
:param meshblock_layer: meshblocks layer
:param task: current task
"""
super().__init__(canvas)
self.canvas = canvas
self.electorate_layer = electorate_layer
self.meshblock_layer = meshblock_layer
self.task = task
self.text_format = QgsTextFormat()
# self.text_format.shadow().setEnabled(True)
self.text_format.background().setEnabled(True)
self.text_format.background().setSize(QSizeF(1, 0))
self.text_format.background().setOffset(QPointF(0, -0.7))
self.text_format.background().setRadii(QSizeF(1, 1))
self.image = None
def redraw(self):
"""
Forces a redraw of the cached image
"""
self.image = None
def paint(self, painter, option, widget): # pylint: disable=missing-docstring, unused-argument, too-many-locals
if self.image is not None:
painter.drawImage(0, 0, self.image)
return
image_size = self.canvas.mapSettings().outputSize()
self.image = QImage(image_size.width(), image_size.height(),
QImage.Format_ARGB32)
self.image.fill(0)
image_painter = QPainter(self.image)
render_context = QgsRenderContext.fromQPainter(image_painter)
image_painter.setRenderHint(QPainter.Antialiasing, True)
rect = self.canvas.mapSettings().visibleExtent()
request = QgsFeatureRequest()
request.setFilterRect(rect)
request.setFilterExpression(
QgsExpression.createFieldEqualityExpression('type', self.task))
for f in self.electorate_layer.getFeatures(request):
# pole, dist = f.geometry().clipped(rect).poleOfInaccessibility(rect.width() / 30)
pixel = self.toCanvasCoordinates(
f.geometry().clipped(rect).centroid().asPoint())
calc = QgsAggregateCalculator(self.meshblock_layer)
calc.setFilter('staged_electorate={}'.format(f['electorate_id']))
estimated_pop, ok = calc.calculate(QgsAggregateCalculator.Sum,
'offline_pop_{}'.format(
self.task.lower())) # pylint: disable=unused-variable
text_string = [
'{}'.format(f['name']), '{}'.format(int(estimated_pop))
]
QgsTextRenderer().drawText(QPointF(pixel.x(), pixel.y()), 0,
QgsTextRenderer.AlignCenter,
text_string, render_context,
self.text_format)
image_painter.end()
painter.drawImage(0, 0, self.image)
class CentroidDecorator(QgsMapCanvasItem):
"""
Decorates centroids of features with population statistics
"""
def __init__(self, canvas: QgsMapCanvas, electorate_layer: QgsVectorLayer,
meshblock_layer: QgsVectorLayer, task: str, quota: int):
"""
Constructor
:param canvas: map canvas
:param electorate_layer: electorates layer
:param meshblock_layer: meshblocks layer
:param task: current task
:param quota: target quota
"""
super().__init__(canvas)
self.canvas = canvas
self.electorate_layer = electorate_layer
self.meshblock_layer = meshblock_layer
self.task = task
self.text_format = QgsTextFormat()
# self.text_format.shadow().setEnabled(True)
self.text_format.background().setEnabled(True)
self.text_format.background().setSize(QSizeF(1, 0))
self.text_format.background().setOffset(QPointF(0, -0.7))
self.text_format.background().setRadii(QSizeF(1, 1))
self.image = None
self.quota = quota
self.original_populations = {}
self.new_populations = {}
def redraw(self, handler):
"""
Forces a redraw of the cached image
"""
self.image = None
if not self.original_populations:
# first run, get initial estimates
request = QgsFeatureRequest()
request.setFilterExpression(QgsExpression.createFieldEqualityExpression('type', self.task))
request.setFlags(QgsFeatureRequest.NoGeometry)
for f in self.electorate_layer.getFeatures(request):
estimated_pop = f.attribute(handler.stats_nz_pop_field_index)
if estimated_pop is None or estimated_pop == NULL:
# otherwise just use existing estimated pop as starting point
estimated_pop = f.attribute(handler.estimated_pop_idx)
self.original_populations[f.id()] = estimated_pop
# step 1: get all electorate features corresponding to affected electorates
electorate_features = {f[handler.electorate_layer_field]: f for f in
handler.get_affected_districts(
[handler.electorate_layer_field, handler.stats_nz_pop_field, 'estimated_pop'],
needs_geometry=False)}
self.new_populations = {}
for district in handler.pending_affected_districts.keys(): # pylint: disable=consider-iterating-dictionary
# use stats nz pop as initial estimate, if available
estimated_pop = electorate_features[district].attribute(handler.stats_nz_pop_field_index)
if estimated_pop is None or estimated_pop == NULL:
# otherwise just use existing estimated pop as starting point
estimated_pop = electorate_features[district].attribute(handler.estimated_pop_idx)
# add new bits
estimated_pop = handler.grow_population_with_added_meshblocks(district, estimated_pop)
# minus lost bits
estimated_pop = handler.shrink_population_by_removed_meshblocks(district, estimated_pop)
self.new_populations[electorate_features[district].id()] = estimated_pop
def paint(self, painter, option, widget): # pylint: disable=missing-docstring, unused-argument, too-many-locals
if self.image is not None:
painter.drawImage(0, 0, self.image)
return
image_size = self.canvas.mapSettings().outputSize()
self.image = QImage(image_size.width(), image_size.height(), QImage.Format_ARGB32)
self.image.fill(0)
image_painter = QPainter(self.image)
render_context = QgsRenderContext.fromQPainter(image_painter)
image_painter.setRenderHint(QPainter.Antialiasing, True)
rect = self.canvas.mapSettings().visibleExtent()
request = QgsFeatureRequest()
request.setFilterRect(rect)
request.setFilterExpression(QgsExpression.createFieldEqualityExpression('type', self.task))
for f in self.electorate_layer.getFeatures(request):
# pole, dist = f.geometry().clipped(rect).poleOfInaccessibility(rect.width() / 30)
pixel = self.toCanvasCoordinates(f.geometry().clipped(rect).centroid().asPoint())
estimated_pop = self.new_populations[f.id()] if f.id() in self.new_populations else \
self.original_populations[f.id()]
variance = LinzElectoralDistrictRegistry.get_variation_from_quota_percent(self.quota, estimated_pop)
text_string = ['{}'.format(f['name']),
'{}'.format(int(estimated_pop)),
'{}{}%'.format('+' if variance > 0 else '', variance)]
QgsTextRenderer().drawText(QPointF(pixel.x(), pixel.y()), 0, QgsTextRenderer.AlignCenter,
text_string, render_context, self.text_format)
image_painter.end()
painter.drawImage(0, 0, self.image)
