Elk- Waterways: Grasshopper Breakpoint

Hey, I have a following problem: I´ve downloaded following OSM datta (though QGIS) and t´put it through grasshopper to draw curves (with the help of Elk2). All of the other components seem to work, but the one I need the most: the Water Ways is retuning only NULLs. Also when it stops computing it says:
Grasshoper breakpoint:
one of the supplied items could not be converted
Parameter type: GH_point
Supplied type: GH_string

____so how can I achieve the conversion? or what is going wrong?
I attach all the files!..except for the OSM which cant be uploaded here …
WeTransfer link for the OSM: https://we.tl/7o521hJEd4

elk|690x350immendingen_map.gh (15.1 KB)

Hi, the problem might be on the type definition inside the component, or of the source of the .osm file, it has happend to me in respect to some Highway points, it seems that some times the (.osm) databases dont follow the OSM file format, so when the component does the query, receive information that doesn’t correspond to the type necesary, or some data is in slightly different format, so it is not recognize by Elk2.

Did you download the .osm from OpenStreetMap, or…?
You have try to download the file from the OpenStreetMap website?

Thank you for the answer!
If I download it directly from https://www.openstreetmap.org/export#map=14/48.1203/8.3840 it works, but you can only download small patches of the map. Thats why I downloaded it through QGIS, where you can download bigger portions of OSM data. Or would you know about other source where you can download the OSM giving him the exact coordinates?

The problem is with the Api, Im pretty sure that Qgis uses the Overpass.Api, so the format of the osm.file from Qgis is different from the format of the file in the website, (it’s because of the file size). Have you try other websites like:


In https://www.openstreetmap.org/export, you can see a panel(left), if you scroll down the panel, you can see a list with 4 different ways of accessing the data of openstreetmap: Overpass, PlanetOSM, Geofabrik, Others.

There are also other OSM plugins for Qgis

Haven’t had any problems with this one:

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It also seems that it depends on the size of the OSM. I even tried two data sets from the same source - one being MB, the other around 9. With the bigger file I again got the Grasshopper breakpoint :frowning: WIth geofabrik (I took for instance Liechtenstein, to keep it small: 55MB), but it had exactly the same problem, so I´m starting to think it´s really depending on the file size. Still - all the other components work, it´s just the Water ways causing the problem!

Yes, I see that on larger datasets. There must be something wrong with the ELK components as I can find all elements in the osm file. When you use the GenericOSM component and you plug in waterway in the K input, you will get rivers out. Putting Natural in K and Water in V doesn’t provide output - even though you will find such entries in the osm file. I’ll check with Gismo when I get a chance…

Had once the same problem, when I wanted to input a big city. I think there are just too much informations for elk to calculate. Asked in the osm forum and they told me to filter the files, to get it smaller. There are plenty of informations you won’t need. Download the files -> convert -> filter. But I can’t tell you how to do it, I asked a geography student from my university :smiley: