6

I am trying to create a closed LineString made of a number of CircularSrings, but have got stuck. I cannot see how to add the geometry from both strings.

This is what I have so far. QGIS version 3.4.2

from qgis.PyQt.QtCore import QVariant

vl = QgsVectorLayer("LineString", "temp", "memory")


pr = vl.dataProvider()
pr.addAttributes([QgsField("name", QVariant.String)])
vl.updateFields() 
cString1 = QgsCircularString.fromTwoPointsAndCenter(QgsPoint(306580,167317),QgsPoint(306680,167317),QgsPoint(306680,167217))
cString2 = QgsCircularString.fromTwoPointsAndCenter(QgsPoint(306680,167317),QgsPoint(306580,167317),QgsPoint(306680,167417))


geom_cString1 = QgsGeometry(cString1)
geom_cString2 = QgsGeometry(cString2)
f = QgsFeature()
f.setGeometry(geom_cString1)
f.setAttributes(["One"])
pr.addFeature(f)
vl.updateExtents() 
QgsProject.instance().addMapLayer(vl)
Taras
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Tilson
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1 Answers1

5

Static collectGeometry method of QgsGeometry class performs what you need.

...
geom_cString1=QgsGeometry(cString1)
geom_cString2=QgsGeometry(cString2)

geom = QgsGeometry().collectGeometry([geom_cString1, geom_cString2])


f = QgsFeature()
f.setGeometry(geom)
...

The closed ring in the image is one LineString geometry.

enter image description here

Kadir Şahbaz
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