Qneat3Utilities.py

# -*- coding: utf-8 -*-
"""
***************************************************************************
    Qneat3Utilities.py
    ---------------------
    
    Date                 : January 2018
    Copyright            : (C) 2018 by Clemens Raffler
    Email                : clemens dot raffler 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 qgis.core import QgsWkbTypes, QgsMessageLog, QgsVectorLayer, QgsFeature, QgsGeometry, QgsFields, QgsField, QgsFeatureRequest

from qgis.PyQt.QtCore import QVariant
from QNEAT3.Qneat3Exceptions import Qneat3GeometryException

def AssignAnalysisCrs(vlayer):
    logPanel("Setting analysis CRS")
    AnalysisCrs = vlayer.crs()
    return AnalysisCrs

def logPanel(message):
    QgsMessageLog.logMessage(message, "QNEAT3")
    
def isGeometryType(vlayer, type_obj):
    geom_type = vlayer.geometryType()
    if geom_type == type_obj:
        return True
    else:
        return False

def buildQgsVectorLayer(string_geomtype, string_layername, crs, feature_list, list_qgsfield):
    
    #create new vector layer from self.crs
    vector_layer = QgsVectorLayer(string_geomtype, string_layername, "memory")
    
    #set crs from class
    vector_layer.setCrs(crs)
    
    #set fields
    provider = vector_layer.dataProvider()
    provider.addAttributes(list_qgsfield) #[QgsField('fid',QVariant.Int),QgsField("origin_point_id", QVariant.Double),QgsField("iso", QVariant.Int)]
    vector_layer.updateFields()
    
    #fill layer with geom and attrs
    vector_layer.startEditing()
    for feat in feature_list:
        vector_layer.addFeature(feat, True)
    vector_layer.commitChanges()

    return vector_layer

def getFeatureFromPointParameter(qgs_point_xy):     
    feature = QgsFeature()
    fields = QgsFields()
    fields.append(QgsField('point_id', QVariant.String, '', 254, 0))
    feature.setFields(fields)
    feature.setGeometry(QgsGeometry.fromPointXY(qgs_point_xy))
    feature['point_id']="Start Point"
    return feature

def getFeaturesFromQgsIterable(qgs_feature_storage):#qgs_feature_storage can be any vectorLayer/QgsProcessingParameterFeatureSource/etc
    fRequest = QgsFeatureRequest().setFilterFids(qgs_feature_storage.allFeatureIds())
    return qgs_feature_storage.getFeatures(fRequest)

def mergeFeaturesFromQgsIterable(qgs_feature_storage_list):
    result_feature_list = []
    for qgs_feature_storage in qgs_feature_storage_list:
        fRequest = QgsFeatureRequest().setFilterFids(qgs_feature_storage.allFeatureIds())
        result_feature_list.extend(qgs_feature_storage.getFeatures(fRequest))
    return result_feature_list
        
        
def getFieldIndexFromQgsProcessingFeatureSource(feature_source, field_name):
    if field_name != "":
        return feature_source.fields().lookupField(field_name)
    else:
        return -1
    
def getListOfPoints(qgs_feature_storage): #qgs_feature_storage can be any vectorLayer/QgsProcessingParameterFeatureSource/etc
    given_geom_type = qgs_feature_storage.wkbType() #GetStringRepresentation of WKB Type

    if given_geom_type == QgsWkbTypes().Point:
        qgsfeatureiterator = getFeaturesFromQgsIterable(qgs_feature_storage)
        return [f.geometry().asPoint() for f in qgsfeatureiterator]
    else:
        raise Qneat3GeometryException(given_geom_type, QgsWkbTypes().Point)
        
def getFieldDatatype(qgs_feature_storage, fieldname):
    fields_list = qgs_feature_storage.fields()
    qvariant_type = fields_list.field(fieldname).type()
    return qvariant_type

def getFieldDatatypeFromPythontype(pythonvar):
    if isinstance(pythonvar, str):
        return QVariant.String
    elif isinstance(pythonvar, int):
        return QVariant.Int
    elif isinstance(pythonvar, float):
        return QVariant.Double
    else: 
        return QVariant.String