I'm not sure if this is possible but would save me hours of work.

I have a layer which consists of polylines. Most of those polylines bound areas; houses, roads, etc.

Currently I am required to colour each of those areas to define what they represent in the real world. My current technique is drawing a region in a new layer; as you can guess this takes a lot of time, especially for complicated areas.

Is there a feature in QGIS whereby I can create a new region on a layer by selecting a point within the bounded area and it creates the region shape?


I have tried converting the whole layer of polylines to regions but the results were not as desired, there are some lines that are not bound to an area (partial fences, walls etc) so the results look odd.

It would be something similar to 'hatching' in an CAD program, to fill the area bound by lines. Only I want to do this to create the region.

  • You want to convert polylines to regions? – Nathan W Jul 31 '13 at 10:59
  • No I tried that with the whole layer but the results were not as desired. – gN87 Jul 31 '13 at 11:29
  • 1
    Why might need a picture of what you have and what you need. – Nathan W Jul 31 '13 at 11:29
  • You can't really create a region from a a non closed polyline. – Nathan W Jul 31 '13 at 11:35

Have you tried the Polygonizer plugin (http://www.gis-support.pl/polygonizer/) to convert a polyline layer to a polygon layer? I've found that it works better than the Lines to Polygons tool built-in to QGIS. If the fast, new method in Polygonizer fails, try the old, slow method but be prepared to give it time. Non-closed polylines will still not produce polygons, however. Where there are open polylines are at the edges of the layer, I draw a bounding box around the layer to close them off first.

  • Many thanks blackthorn. That works 95% of the way I need it to, and will probably save me days of work. – gN87 Aug 1 '13 at 9:49

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