punti_lungo_linea.py

"""
***************************************************************************
    punti_lungo_linea.py
    ---------------------
    Version              : 1.0
    Date                 : 28/10/2022
    Copyright            : (C) 2022 by Andrea Giudiceandrea
    Email                : andreaerdna at libero dot it
***************************************************************************
*                                                                         *
*   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     *
*   any later version.                                                    *
*                                                                         *
***************************************************************************
"""


def punti_lungo_linea(lista_distanze):

    layer = iface.activeLayer()
    if not layer: return

    selected_features = layer.selectedFeatures()
    if not len(selected_features) > 0: return

    geometria_linea = selected_features[0].geometry()
    lunghezza_linea = geometria_linea.length()

    punti = []
    for dist in lista_distanze:
        if 0 <= dist <= lunghezza_linea:
            punti.append([dist, geometria_linea.interpolate(dist)])
    if not len(punti) > 0: return

    features = []
    for dist, punto in punti:
        feat = QgsFeature()
        feat.setGeometry(punto)
        feat.setAttributes([dist])
        features.append(feat)

    uri = "Point?crs={}&field=dist:double".format(layer.sourceCrs().authid())
    virt_layer = QgsVectorLayer(uri, "Punti lungo la linea", "memory")
    virt_layer.dataProvider().addFeatures(features)
    virt_layer.updateExtents()
    QgsProject.instance().addMapLayer(virt_layer)
    iface.setActiveLayer(layer)