intersectionlineoverlapping-featurespolygon-creationqgis
I want to create new polygons from the intersecting polygon and polylines shown in the images below. At the output, I need to get four polygons representing the polygons shown in the top image after the polylines are overlaid onto the main polygon.
Any thoughts on how I can do this, please?
The toolbox is the logical place to start, but I believe you may be better suited to going with the editing tools.
There's a post here saying how you can do it in ArcGIS ten using "Topology": http://forums.arcgis.com/threads/48073-Split-polygon-with-line-doesn-t-work
Alternately, you can probably "cheat". Use the "buffer" tool to create a one-sided buffer around the polylines. If you choose the correct side (either left or right, just experiment), and make the buffer of a thousand miles say, you'll then be able to clip erase by this new buffer and the only bit of the polygon remaining will be on the other side of the line.
You can use Layer > Add delimited text layer
For more about this, you can read: Visualising WKT geometry string in QGIS
Best Answer
Use the "Split with lines" geoalgorithm.
Before:
After:
Afterwards the application of the "Remove null geometries" and "Delete duplicate geometries" geoalgorithms is recommended.