QGIS/python/plugins/processing/algs/qgis/PointsLayerFromTable.py
2017-08-22 23:36:42 +10:00

142 lines
5.8 KiB
Python

# -*- coding: utf-8 -*-
"""
***************************************************************************
PointsLayerFromTable.py
---------------------
Date : January 2013
Copyright : (C) 2013 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 2013'
__copyright__ = '(C) 2013, Victor Olaya'
# This will get replaced with a git SHA1 when you do a git archive
__revision__ = '$Format:%H$'
from qgis.core import (QgsApplication,
QgsWkbTypes,
QgsPoint,
QgsFeatureRequest,
QgsGeometry,
QgsProcessing,
QgsProcessingParameterFeatureSink,
QgsProcessingParameterFeatureSource,
QgsProcessingParameterCrs,
QgsProcessingParameterField)
from processing.algs.qgis.QgisAlgorithm import QgisAlgorithm
class PointsLayerFromTable(QgisAlgorithm):
INPUT = 'INPUT'
XFIELD = 'XFIELD'
YFIELD = 'YFIELD'
ZFIELD = 'ZFIELD'
MFIELD = 'MFIELD'
OUTPUT = 'OUTPUT'
TARGET_CRS = 'TARGET_CRS'
def tags(self):
return self.tr('points,create,values,attributes').split(',')
def group(self):
return self.tr('Vector creation')
def __init__(self):
super().__init__()
def initAlgorithm(self, config=None):
self.addParameter(QgsProcessingParameterFeatureSource(self.INPUT, self.tr('Input layer'), types=[QgsProcessing.TypeVector]))
self.addParameter(QgsProcessingParameterField(self.XFIELD,
self.tr('X field'), parentLayerParameterName=self.INPUT, type=QgsProcessingParameterField.Any))
self.addParameter(QgsProcessingParameterField(self.YFIELD,
self.tr('Y field'), parentLayerParameterName=self.INPUT, type=QgsProcessingParameterField.Any))
self.addParameter(QgsProcessingParameterField(self.ZFIELD,
self.tr('Z field'), parentLayerParameterName=self.INPUT, type=QgsProcessingParameterField.Any, optional=True))
self.addParameter(QgsProcessingParameterField(self.MFIELD,
self.tr('M field'), parentLayerParameterName=self.INPUT, type=QgsProcessingParameterField.Any, optional=True))
self.addParameter(QgsProcessingParameterCrs(self.TARGET_CRS,
self.tr('Target CRS'), defaultValue='EPSG:4326'))
self.addParameter(QgsProcessingParameterFeatureSink(self.OUTPUT, self.tr('Points from table'), type=QgsProcessing.TypeVectorPoint))
def name(self):
return 'createpointslayerfromtable'
def displayName(self):
return self.tr('Create points layer from table')
def processAlgorithm(self, parameters, context, feedback):
source = self.parameterAsSource(parameters, self.INPUT, context)
fields = source.fields()
x_field_index = fields.lookupField(self.parameterAsString(parameters, self.XFIELD, context))
y_field_index = fields.lookupField(self.parameterAsString(parameters, self.YFIELD, context))
z_field_index = -1
if self.parameterAsString(parameters, self.ZFIELD, context):
z_field_index = fields.lookupField(self.parameterAsString(parameters, self.ZFIELD, context))
m_field_index = -1
if self.parameterAsString(parameters, self.MFIELD, context):
m_field_index = fields.lookupField(self.parameterAsString(parameters, self.MFIELD, context))
wkb_type = QgsWkbTypes.Point
if z_field_index >= 0:
wkb_type = QgsWkbTypes.addZ(wkb_type)
if m_field_index >= 0:
wkb_type = QgsWkbTypes.addM(wkb_type)
target_crs = self.parameterAsCrs(parameters, self.TARGET_CRS, context)
(sink, dest_id) = self.parameterAsSink(parameters, self.OUTPUT, context,
fields, wkb_type, target_crs)
request = QgsFeatureRequest().setFlags(QgsFeatureRequest.NoGeometry)
features = source.getFeatures()
total = 100.0 / source.featureCount() if source.featureCount() else 0
for current, feature in enumerate(features):
if feedback.isCanceled():
break
feedback.setProgress(int(current * total))
attrs = feature.attributes()
try:
x = float(attrs[x_field_index])
y = float(attrs[y_field_index])
point = QgsPoint(x, y)
if z_field_index >= 0:
try:
point.addZValue(float(attrs[z_field_index]))
except:
point.addZValue(0.0)
if m_field_index >= 0:
try:
point.addMValue(float(attrs[m_field_index]))
except:
point.addMValue(0.0)
feature.setGeometry(QgsGeometry(point))
except:
pass # no geometry
sink.addFeature(feature)
return {self.OUTPUT: dest_id}