2024-11-29 15:38:02 +01:00

113 lines
3.4 KiB
Python

"""
***************************************************************************
Buffer.py
---------------------
Date : August 2012
Copyright : (C) 2012 by Victor Olaya
Email : volayaf at gmail dot com
***************************************************************************
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; either version 2 of the License, or *
* (at your option) any later version. *
* *
***************************************************************************
"""
__author__ = "Victor Olaya"
__date__ = "August 2012"
__copyright__ = "(C) 2012, Victor Olaya"
from qgis.core import Qgis, QgsFeature, QgsGeometry, QgsFeatureRequest, QgsFeatureSink
def buffering(
feedback,
context,
sink,
distance,
field,
useField,
source,
dissolve,
segments,
endCapStyle=1,
joinStyle=1,
miterLimit=2,
):
if useField:
field = source.fields().lookupField(field)
outFeat = QgsFeature()
current = 0
total = 100.0 / source.featureCount() if source.featureCount() else 0
# With dissolve
if dissolve:
attributes_to_fetch = []
if useField:
attributes_to_fetch.append(field)
features = source.getFeatures(
QgsFeatureRequest().setSubsetOfAttributes(attributes_to_fetch)
)
buffered_geometries = []
for inFeat in features:
if feedback.isCanceled():
break
attrs = inFeat.attributes()
if useField:
value = attrs[field]
else:
value = distance
inGeom = inFeat.geometry()
buffered_geometries.append(
inGeom.buffer(
float(value),
segments,
Qgis.EndCapStyle(endCapStyle),
Qgis.JoinStyle(joinStyle),
miterLimit,
)
)
current += 1
feedback.setProgress(int(current * total))
final_geometry = QgsGeometry.unaryUnion(buffered_geometries)
outFeat.setGeometry(final_geometry)
outFeat.setAttributes(attrs)
sink.addFeature(outFeat, QgsFeatureSink.Flag.FastInsert)
else:
features = source.getFeatures()
# Without dissolve
for inFeat in features:
if feedback.isCanceled():
break
attrs = inFeat.attributes()
if useField:
value = attrs[field]
else:
value = distance
inGeom = inFeat.geometry()
outFeat = QgsFeature()
outGeom = inGeom.buffer(
float(value),
segments,
Qgis.EndCapStyle(endCapStyle),
Qgis.JoinStyle(joinStyle),
miterLimit,
)
outFeat.setGeometry(outGeom)
outFeat.setAttributes(attrs)
sink.addFeature(outFeat, QgsFeatureSink.Flag.FastInsert)
current += 1
feedback.setProgress(int(current * total))