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Is it possible to smooth or generalize a polygon in qgis? Ìs there a plugin available like the generalizer-plugin for lines? I could convert my polygons to lines, smooth them and convert them back to polygones. But this is not working for my polygons because of sveral reasons.

Any idea? Thanks!

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1 Answer 1

up vote 6 down vote accepted

you can use:

Vector menu -> Geometry tools -> Simplify Geometries



Beside this you can use Douglas-Peucker algorithm in postgis too, so you can use in postgis then adding postgis layer to qgis. you can find some info here about Simplify: Reduce the weight of a geometry.

SELECT simplify(the_geom,500) as simpgeom 
    FROM neighborhoods


i hope it helps you...

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That simplifies the lines, making them more jagged. Is there a way to smooth them(which I guess would have to interpolate some points)? –  Nate Wessel Dec 23 '12 at 17:13

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