(Feature Request) add map renderer about trekme HOT 8 CLOSED

TrekMe already has a built-in feature for downloading tiles for an offline usage.
If you go to Create a map > OpenStreetMap, you select your area and all tiles are downloaded.
Do you mean that it would be nice to import .osm files and create a map from it?
If so, that feature would be accessible from the main menu > Import a map

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When trying to import a map from a .osm file, it's giving me a blank screen with a download F.A.B in the bottom right corner, so while that feature may work in other cases it's not what I'm looking for.

I'm talking about making a rendering system in the app, so that you need only load a .osm file, not import it.

Rendering the OSM instead of displaying pre-rendered tiles would reduce storage usage and would leave options open for routing and navigation in the future.

Finally, rendering the OSM data on the device lets you allow the user to have any LOD they want, without having separate datasets for it, keeping the same data size and effectively unlocking the zoom limits. Like how vector fonts are more useful than raster fonts when doing graphic design.

I'm fairly sure using a VectorDrawable would work great, when feeding in the right data.

I've been out of practise with android for quite some time now, but if you want me to I may be able to create an example activity once I get some downtime to show you what I mean?

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Better yet, you could let someone else do all the work and use https://github.com/mapsforge/mapsforge

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Well, I developed a library for rendering maps: https://github.com/peterLaurence/MapView
TrekMe uses that library.
It might be possible to directly render from an .osm file. Do you know how graphic data is stored in there? Is is tile-based, vector data?

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Attached at the bottom is an excerpt from the OpenStreetMap Wiki.
It seems to be an XML schema, so loading it and manipulating it should be relatively easy.
If I were to do it, I'd probably project the points (as they are coordinates) and then render it like a vector image, using the tags (e.g. <tag k="highway" v="crossing"> to decide colouring and how zoomed in you have to be to render it.
If you want to re-use your existing code you could add a function which renders the OSM data to tiles as they're being loaded by MapView, letting you re-use the same bounding, zooming and chunking code.
Should you not want to do all of this, you can use the library I mentioned earlier that will handle it for you, and stores the data in a binary intermediate.

<?xml version="1.0" encoding="UTF-8"?>
<osm version="0.6" generator="CGImap 0.0.2">
 <bounds minlat="54.0889580" minlon="12.2487570" maxlat="54.0913900" maxlon="12.2524800"/>
 <node id="298884269" lat="54.0901746" lon="12.2482632" user="SvenHRO" uid="46882" visible="true" version="1" changeset="676636" timestamp="2008-09-21T21:37:45Z"/>
 <node id="261728686" lat="54.0906309" lon="12.2441924" user="PikoWinter" uid="36744" visible="true" version="1" changeset="323878" timestamp="2008-05-03T13:39:23Z"/>
 <node id="1831881213" version="1" changeset="12370172" lat="54.0900666" lon="12.2539381" user="lafkor" uid="75625" visible="true" timestamp="2012-07-20T09:43:19Z">
  <tag k="name" v="Neu Broderstorf"/>
  <tag k="traffic_sign" v="city_limit"/>
 </node>
 ...
 <node id="298884272" lat="54.0901447" lon="12.2516513" user="SvenHRO" uid="46882" visible="true" version="1" changeset="676636" timestamp="2008-09-21T21:37:45Z"/>
 <way id="26659127" user="Masch" uid="55988" visible="true" version="5" changeset="4142606" timestamp="2010-03-16T11:47:08Z">
  <nd ref="292403538"/>
  <nd ref="298884289"/>
  ...
  <nd ref="261728686"/>
  <tag k="highway" v="unclassified"/>
  <tag k="name" v="Pastower Straße"/>
 </way>
 <relation id="56688" user="kmvar" uid="56190" visible="true" version="28" changeset="6947637" timestamp="2011-01-12T14:23:49Z">
  <member type="node" ref="294942404" role=""/>
  ...
  <member type="node" ref="364933006" role=""/>
  <member type="way" ref="4579143" role=""/>
  ...
  <member type="node" ref="249673494" role=""/>
  <tag k="name" v="Küstenbus Linie 123"/>
  <tag k="network" v="VVW"/>
  <tag k="operator" v="Regionalverkehr Küste"/>
  <tag k="ref" v="123"/>
  <tag k="route" v="bus"/>
  <tag k="type" v="route"/>
 </relation>
 ...
</osm>

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Alright. Ideally, that could be transformed so that it could be read as vector tiles, like that. Using a custom renderer (using a third party library), that could work using MapView.
Do you know if there's a way to turn a big single .osm file into a stream of vector tiles?

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This looks interesting:
https://dev.to/camptocamp-geo/creating-vector-tiles-from-openstreetmap-with-baremaps-jln

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