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#1 2016-02-15 21:26:43

Registered: 2016-02-15
Posts: 0

Harbor app


Me and another guy are building a crossplatform app, with harbor information for sailors. We would really love to use Openseamap. But we are having troubles with getting it to work when you only have GPS signal. We were thinking about having inapp-downloads of tiles big enough to ensure you dont run out of map from sailing one day. But as far as i have been able to see the downloadable maps are outdated?

A 2 year old post suggests that we 2 choices: "to cache pre-rendered tiles or to dynamically render from a cached database". Is this still the case and is it possible to get any pointers on how to implement into a html/js project.

And I am not the best programmer, so I am sorry if I ask some stupid questions. (Luckily my buddy is more experienced smile )



#2 2016-02-16 08:11:27

From: Hull, UK
Registered: 2012-09-05
Posts: 194

Re: Harbor app

You can use OSM utilities, such as OverPass, to extract all objects with "seamark:type=harbour" and "seamark:type=anchorage" tags. See:

Malcolm Herring, Developer


#3 2016-05-11 05:55:00

Registered: 2012-09-25
Posts: 69

Re: Harbor app

Hi Christian,

I am not sure Malcolms tip is what you ask for?
I did understand, you want to have complete offline maps in your app. Which map file format are you using, if that is already defined?

Currently we are restarting the production of BSB/KAP file charts which we bundle into one chart bundle for a region each.
These downloads are a few hundred MB big, intended for download before going on board.




#4 2016-08-22 10:29:08

From: Bremen, Germany
Registered: 2012-09-05
Posts: 41

Re: Harbor app

Offline caching for huge amounts of data (bitmap data) is always a really hard tradeoff between lots and lots of data to download (and a server to bear that download-load) and freshness of the data.

With the iOS OpenSeaMap client I went with on the fly caching of what you have visited on the chart recently. I really was thinking hard about how to change this in the latest release one week ago, but since we still have bitmap data and no vector tiles yet, this is an approach where server-load and freshness of the data are both met. … 10783?mt=8

but I absolutely understand that a 100 percent offline map would be best. I like to be independent from any network too as soon as I leave the marina.

Nautical greetings from Bremen,

Developer of the OpenSeaMap app for iOS (iPhone, iPod & iPad)
OpenSeaMap app on the AppStore


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