QGIS/python/plugins/sextante/algs/PointsLayerFromTable.py

# -*- 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.                                   *
*                                                                         *
***************************************************************************
"""
from sextante.parameters.ParameterTable import ParameterTable
from sextante.parameters.ParameterTableField import ParameterTableField

__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 sextante.core.GeoAlgorithm import GeoAlgorithm
from PyQt4.QtCore import *
from PyQt4.QtGui import *
from qgis.core import *
from sextante.core.QGisLayers import QGisLayers
from sextante.outputs.OutputVector import OutputVector

class PointsLayerFromTable(GeoAlgorithm):

    INPUT = "INPUT"
    XFIELD = "XFIELD"
    YFIELD = "YFIELD"
    OUTPUT = "OUTPUT"

    #===========================================================================
    # def getIcon(self):
    #    return QtGui.QIcon(os.path.dirname(__file__) + "/../images/toolbox.png")
    #===========================================================================

    def processAlgorithm(self, progress):
        source = self.getParameterValue(self.INPUT)
        vlayer = QGisLayers.getObjectFromUri(source)
        output = self.getOutputFromName(self.OUTPUT)
        vprovider = vlayer.dataProvider()
        fields = vprovider.fields()
        writer = output.getVectorWriter(fields, QGis.WKBPoint, self.crs)
        xfieldindex = vlayer.fieldNameIndex(self.getParameterValue(self.XFIELD))
        yfieldindex = vlayer.fieldNameIndex(self.getParameterValue(self.YFIELD))

        outFeat = QgsFeature()
        nElement = 0
        features = QGisLayers.features(vlayer)
        nFeat = len(features)
        for feature in features:
            nElement += 1
            progress.setPercentage((nElement*100)/nFeat)
            attrs = feature.attributes()
            try:
                x =  float(attrs[xfieldindex].toString())
                y =  float(attrs[yfieldindex].toString())
            except:
                continue
            pt = QgsPoint(x, y)
            outFeat.setGeometry(QgsGeometry.fromPoint(pt))
            outFeat.setAttributes(attrs)
            writer.addFeature(outFeat)

        del writer


    def defineCharacteristics(self):
        self.name = "Points layer from table"
        self.group = "Vector creation tools"
        self.addParameter(ParameterTable(self.INPUT, "Input layer"))
        self.addParameter(ParameterTableField(self.XFIELD, "X field", self.INPUT, ParameterTableField.DATA_TYPE_NUMBER))
        self.addParameter(ParameterTableField(self.YFIELD, "Y field", self.INPUT, ParameterTableField.DATA_TYPE_NUMBER))
        self.addOutput(OutputVector(self.OUTPUT, "Output layer"))