Le portail francophone de la géomatique

from qgis.core import QgsProcessing
from qgis.core import QgsProcessingAlgorithm
from qgis.core import QgsProcessingMultiStepFeedback
from qgis.core import QgsProcessingParameterVectorLayer
from qgis.core import QgsProcessingParameterFeatureSink
import processing


class TransformerCoucheVecteur(QgsProcessingAlgorithm):

    def initAlgorithm(self, config=None):
        self.addParameter(QgsProcessingParameterVectorLayer('couchevecteur', 'couche vecteur', types=[QgsProcessing.TypeVectorAnyGeometry], defaultValue=None))
        self.addParameter(QgsProcessingParameterFeatureSink('Tampon', 'tampon', type=QgsProcessing.TypeVectorPolygon, createByDefault=True, defaultValue=None))

    def processAlgorithm(self, parameters, context, model_feedback):
        # Use a multi-step feedback, so that individual child algorithm progress reports are adjusted for the
        # overall progress through the model
        feedback = QgsProcessingMultiStepFeedback(1, model_feedback)
        results = {}
        outputs = {}

        # Tampon
        alg_params = {
            'DISSOLVE': True,
            'DISTANCE': 4,
            'END_CAP_STYLE': 0,
            'INPUT': parameters['couchevecteur'],
            'JOIN_STYLE': 1,
            'MITER_LIMIT': 1,
            'SEGMENTS': 1,
            'OUTPUT': parameters['Tampon']
        }
        outputs['Tampon'] = processing.run('native:buffer', alg_params, context=context, feedback=feedback, is_child_algorithm=True)
        results['Tampon'] = outputs['Tampon']['OUTPUT']
        return results

    def name(self):
        return 'transformer couche vecteur'

    def displayName(self):
        return 'transformer couche vecteur'

    def group(self):
        return ''

    def groupId(self):
        return ''

    def createInstance(self):
        return TransformerCoucheVecteur()