OpenSeaMap - it it still alive?

The title says it all, but I’m hoping that maybe somebody here may have an idea. While the forum, site and tile server are all up, they level of activity is incredibly low (mainly new users). Also, changes made to the seamark:* elements aren’t being reflected on the map layer.

I’ve asked at the following places:

Most specifically, I’m interested in what tools they currently use to render tiles. I’ve forked and updated the JOSM Plugins in order to get them to work with Tirex, but the tiles being generated don’t match those from the official tile server (lighthouses, etc), so I have a feeling I’m busy patching osbolete tools (which while fun seems a little pointless).

I know there was a bit of a schism a while back with OpenNauticalChart but that appears less active.

Some questions I have:

  • Is the source for the tools available, or is it essentially closed (see my reponse to Mateusz_Konieczny)?
  • Does anyone know who is active in running the project?

Many thanks,

OpenSeaMap - OpenStreetMap Wiki links OpenSeaMap - the free nautical chart · GitHub

Sorry, I should have phrased that a lot better…

There is plenty of source code available on the GitHub for OpenSeaMap. The problem I’m having is that while there is plenty of source available for the front end, I can’t find any available for rendering the actual tiles.

For example, these repos sound promising, but…

  • alpha-seamark-docker but it’s just an nginx docker which serves tiles from a mounted volume.
  • osm-tileserver but it only does Mapnik rendering, plus the docker images won’t even build because it using tools and services that are deprecated
  • osm-tileserver, this effectivly links to the JOSM jrender code, but as I said originally, that doesn’t render the same results as the live site.

Here are 3 tiles (12/1979/1326), as you see they’re quite different:

Funnily enough, the jrender.jar program provided in pyrenderer does render tiles similar to the live ones, but that uses a compiled jar file, so it’s probably been built from a fork of the JOSM repo.

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AFAIK they currently have server issues (out of disk space) and are working it.

Generally, the SeaMap community seems to be much smaller than the rest, but there are some pretty active contributors.

@quantenschaum Thanks, funnily enough I just got a reply on the OpenSeaMap forums from Malcolm about this yesterday. So I’ve asked him a couple of follow up questions about rendering, etc.

I once had the use case of “create OpenSeaMap tiles on a tile server that has a standard OSM Carto PostGIS database”. All the existing rendering tools assumed that you have a local OSM file with the data. I then made a modified version of jrender that works off a database, - at the time I made it, its output was almost identical to standard OpenSeaMap tiles. I don’t know if this is still in use by anybody though.

So it turned out to be a case of RTFM (actually RTFSC).

I had being used to using an older version of the JRender executable which accepts any OSM file. The current master branch requires that the provided OSM file has a bounds element which is created in turn by the JSearch executable, and it was failing silently.

I had also refactored the code in order to get the JRenderSQL executable to work for my tile server that uses Tirex, and in doing so I copy-pasted the calculation for the distance of the mile, which caused the lighthouses not to be rendered corrected.

TLDR: It was me that screwed up. Apologies for casting any aspersions.

Hi Frederick. It’s cool to hear from the person that wrote that tool! I’ve made a few patches to it it in order to get it to build from the current master branch. I also made some changes like using the XmlDocument to generate the OSM file, rather than hand writing it, which improved the performance a bit and made it less error-prone.

I’m now using it on my personal tiler server, and [now that I’ve fixed my bugs] it’s working beautifully!

nice to hear about other people interested in openseamap project :wink:
I am myself trying to improved datas of seamarks by adding some
but i am facing few difficulties:

  • How is the process of updating seamarks charts ?
  • How long it take to apply modification?
  • where are the mapping object ↔ icons for the charts ?

Improvement possibilities:

  • add icons for gates
  • better icons for bridges

I tryied to add seamark objects for gate and bridge but so far there is no icons showed on the map

Would be really awesome to have a new layer here for nautical charts :

I am entering in the project but for now I am a bit lots ^^

There is not much at official IHO Geospatial Information Registry (search for lock/bridge).

Updating seamarks is the same as updating other OSM data. Use an editor like JOSM, download data, edit/add/remove, upload. You may want to use these presets GitHub - OpenNauticalChart/josm: Presets, styles & icons for our various JOSM tools.

Your modification is available im OSM data instantly after the changeset was uploaded.

You hav to distinguish between the database and other data derived from the data in the database. The OSM database is used to render map tiles, that can be viewed at It take some hours for changes to appear on this map, the tiles have to be rerendered after a change in the DB. The tiles at are the same as on the OSM map plus and additional transparent overlay containing seamarks. It also takes some hours for changes to appear on the map.

But there are other renderers/application that use OSM data. uses OSM data. The data is converted in their own dataformat OBF, these files are updated every month. They also provide their own map tiles at OsmAnd Map. And JOSM also renders OSM data, but how depends on the mapcss configured in the settings. You can also use QGIS to create your own maps like this (also enable “OsmAnd Nautical” layer in the upper right)

In general, there is no single definition of how objects in the OSM DB are rendered on the map. There are many different styles for different use cases. You edit just entries in a database and how they will look on a map depends on the renderer. The appearance of nautical charts on ONC is close to the INT1

Symbols for locks and gates can be found section F of the INT1, bridges with clearance heights/widths in section D.

Thanks for the input, just updated Template:Seamarks references en - OpenStreetMap Wiki
Hope this helps, Dirk