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I work with QGIS and I tried to convert polygon into point. I need points all over the perimeter of the polygon. I saw several answers like:

Problems converting polygon to point

but I didn't see an answer.

Community
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newGIS
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    Could you please edit your question and add what you tried and what error messages (if any) you received? Have you tried using the SAGA tool Convert polygon/line vertices to points from the Processing Toolbox? – Joseph Jan 14 '15 at 10:31
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    You should also specify if you want a single (center) point or all corner points of the polygon. – AndreJ Jan 14 '15 at 11:45

1 Answers1

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In QGIS to convert a polygon into a point you would use the Polygon Centroids tool.

This is found under Vector>Geometry Tools>Centroids...

This will also preserve attributes and puts the point in the geometric centroid of the polygon.

Edit:

For points around the perimeter, you will want, as mentioned, Vector>Geometry Tools>Extract Nodes... This will also preserve attributes.

A few things to note that might be useful. If you want more dense points you can use the: Vector>Geometry Tools>Densify Geometries...

The number of vertices to add is how many nodes will be added to each segment. So a box with 4 nodes to begin with, and densified by 4 will contain 20 nodes, 4 added to each side (segment).

Also after run, each of the Extracted Nodes will be their own geometry, so running the: Vector>Geometry Tools>Singleparts to multipart... Using some unique id in the original polygons, to create a multipart point.

HeikkiVesanto
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