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Please help, our community has been vastly improving the data on OpenStreetMap for a number of weeks now video "Carse of Gowrie Community Resilience Mapping Group". Our aim was to import this into QGIS so that we do more with this data in terms of analysis, visualisation, etc. We have encountered a major problem however! Data entered into OSM (Potlatch 2) as lines or polygons; for example, households, parks, paths and roads; when exported as OSM XML data and imported into QGIS...they are showing up as a series of nodes (points) instead! An example of this can be illustrated here: screenshots. Furthermore, data download services such as GeoFabrik.de do not seem to contain these new features that we have added...even though they are rendered on OpenStreetMap.org; so this is not really an alternative solution either. Please help us. I feel this problem could have serious connotations for community's ability to create updated and themed spatial data layers from OSM data. |
The question has been closed for the following reason "Problem is outdated. This question and answer referred to the old OSM Plugin for QGIS versions 1.x. QGIS has used a different way to access OSM data from 2.0 upwards. Problem is unlikely to be encountered in the future." by SK53 15 Dec '14, 15:27
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I have checked the data thoroughly and found that it is due to the 64 bit problem. see here http://wiki.openstreetmap.org/wiki/64-bit_Identifiers . Quantum GIS OpenStreetMap plugin has not been updated yet. You will have to use other methods. Indeed, and this bug was already noted on the plugin's wiki page. I have now added this info to the main QGIS page, too.
(30 Mar '13, 15:48)
aseerel4c26 ♦
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It is said that, the solution will be released with QGIS 2.0, seriously waiting for that.
(30 Mar '13, 16:03)
amritkarma
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"It is said" where? I've posted a fat ugly note on this page about the problem: http://wiki.openstreetmap.org/wiki/QGIS_OSM_Plugin If anyone knows more about a fix, add some details on there.
(13 Apr '13, 19:54)
Harry Wood
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I have successfully replicated your problem using data for the area you show in your images. I have tried the following: a) Export direct using the OSM export tag; b) downloading the area using the (old) QGIS plugin; and c) downloading the area using JOSM. In each case the buildings around here only show up as nodes not polygons. I checked that the XML for one of these buildings was well-formed in my JOSM extract, it was. Therefore I selected all ways with the building tag in JOSM and copied these to a separate layer and saved this as another OSM XML file. This file displays as expected in QGIS: all the building polygons are present. I also, for comparison, loaded another XML file sitting on my desktop which contains several 1000 building polygons. I noticed no problems with this. However in doing further research your problem is certainly this : http://gis.stackexchange.com/questions/52764/qgis-openstreetmap-plugin-misbehaviour. The QGIS plugin is old and does not cope with 64-bit identifiers. The reason why I could read a copied layer in with JOSM is that this will have new identifiers well below the 64-bit limit. This does provide a potential short-term workaround, BUT be very careful not to upload such data back to OSM. 1
Further to this I note that you have 15 solitary nodes some of which have key names with spaces e.g., "Stobie 1783" and "1860 name". I strongly suspect that this is your problem! I would recommend NOT starting a tag name with a number AND always using '_' or ':' to separate elements in the tag name.
(30 Mar '13, 14:58)
SK53 ♦
how do we copy only selected objects to new layer, i didn't find such option?
(08 Apr '13, 18:02)
amritkarma
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I have been playing with qgis recently too. The OSM plugin gave me nothing but trouble. The best way I found to go was to set up a postgre database, and use osm2pgsql to load in the data to that DB and then add it as a postgis layer in qgis. For small extracts the osm2pgsql loading happens almost instantly and each time you run it it will just overwrite the existing data in the DB so you can load, do some work, then reload in a new area very easily. Detailed instructions are here (you need a couple minor tweaks for the new postgre 9.1 but nothing too serious) under the section 'Through postgis'. http://hub.qgis.org/projects/quantum-gis/wiki/Using_OpenStreetMap_data 1
Andrew, you might like to move this to the follow-up question I just created from Paul Georgie's comment.
(30 Mar '13, 16:36)
SK53 ♦
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"Lines and polygons" consist of nodes in the OSM data representation (see wiki page about "elements"). The exported XML (example) contains nodes and ways. Probably you are missing to import/visualize the ways (again: see our data elements) into QGIS. Our wiki page on "QGIS" lists several help/tutorials to work with OSM data in QGIS. 1
Thank you for responding so quickly. Is there a specific step here that I am missing? One the export .osm file has been downloaded, I use the OSM plug in to import into QGIS ('Load OSM from file'); I de-select 'Use custom renderer' and click OK. Where in this process would I import and visualise the ways? The exported XML example file you provide is working fine, however the XML data coming from our community area is not...as the XML data is made mostly of the points (nodes) that should in fact be getting stored as lines and polygons (example). How can I ensure that the ways between these nodes are imported?
(30 Mar '13, 13:43)
paulgeorgie
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