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Idea: community map like openstreetmap.community

Open neteler opened this issue 5 years ago • 15 comments

Just came across this site: https://openstreetmap.community/

Pretty nice idea as it shows you what's available in your region, for example Southern America:

image

Might be nice to do this for GRASS GIS as well.

neteler avatar May 28 '20 20:05 neteler

Might be nice to do this for GRASS GIS as well.

I like the idea of the map but I don't think that "community map" is the more appropriate since we have not many communities as OSM, probably an user map could be more useful.

We could add a geojson file ad user can add them self doing PR (also editing the file online).

I can work on it if you like the idea

lucadelu avatar May 28 '20 21:05 lucadelu

I really like the idea of having a user map in the website :)

veroandreo avatar May 29 '20 13:05 veroandreo

I started to work on it. Following a preview

community_map

I would like to improve the map with:

  • [x] a layer of companies/universities/etc contributing GRASS GIS
  • [x] show contributors to GRASS, this could be done with a new layer or with adding a new attribute field to user.geojson, do you have any preference?

lucadelu avatar Jun 07 '20 13:06 lucadelu

will this be a separate page or a widget in the side panel of About/Community, for example?

veroandreo avatar Jun 07 '20 20:06 veroandreo

separate page

lucadelu avatar Jun 07 '20 21:06 lucadelu

One more thing. Given that CRS are so relevant for GRASS users, is it possible to use a different projection than that one? Greenland and Antarctica look so big and Africa so small...

An equal area projection like Mollweide, Hammer, Goode homolosine, among others, would look much better in my opinion

veroandreo avatar Jun 08 '20 23:06 veroandreo

I think your proposal does not fit properly with a web map. The used project is the OpenLayers default one, this is a projection developed by google specifically for web map.

However if we want to change projection we need to find a base layer with the chosen projection because OSM is provided only in Google projection.

lucadelu avatar Jun 09 '20 13:06 lucadelu

I think your proposal does not fit properly with a web map. The used project is the OpenLayers default one, this is a projection developed by google specifically for web map.

However if we want to change projection we need to find a base layer with the chosen projection because OSM is provided only in Google projection.

Should be possible to reproject: https://openlayers.org/en/master/examples/reprojection.html.

mlennert avatar Jun 09 '20 13:06 mlennert

I think your proposal does not fit properly with a web map. The used project is the OpenLayers default one, this is a projection developed by google specifically for web map.

This doesn't necessarily make it a good projection ;-)

However if we want to change projection we need to find a base layer with the chosen projection because OSM is provided only in Google projection.

Ok, I see the point. It might be something like

  • https://openlayers.org/en/latest/examples/sphere-mollweide.html
  • https://epsg.io/8857

Of course it's fine to address that in a separate PR.

neteler avatar Jun 09 '20 13:06 neteler

Should be possible to reproject: https://openlayers.org/en/master/examples/reprojection.html.

yes, did you see the result when you choose Mollweide in the View projection? For my point of view is really ugly

lucadelu avatar Jun 09 '20 14:06 lucadelu

it looks like Mollweide

image

veroandreo avatar Jun 09 '20 14:06 veroandreo

it looks like Mollweide

image

in the central World it is fine, but in the corner no

mollwaide

probably with a base layer provided in Mollweide projection the corners could be better

lucadelu avatar Jun 09 '20 14:06 lucadelu

Should be possible to reproject: https://openlayers.org/en/master/examples/reprojection.html.

yes, did you see the result when you choose Mollweide in the View projection? For my point of view is really ugly

;-) Question of aesthetics, I guess. But these aesthetics are unfortunately strongly influenced by the classroom Mercator maps we grew up with...

Also watch out, on that page, you cannot zoom out to the entire world view. Does this look ugly to you, too: https://en.wikipedia.org/wiki/Mollweide_projection#/media/File:Mollweide_projection_SW.jpg ?

You can go through some of the 'world' projections in QGIS and see what pleases you most, but IMHO it should be some equal area one.

mlennert avatar Jun 09 '20 14:06 mlennert

Here are some others (overlapping with some of Markus' suggestions): https://en.wikipedia.org/wiki/Equal_Earth_projection https://en.wikipedia.org/wiki/Gall%E2%80%93Peters_projection https://en.wikipedia.org/wiki/Strebe_1995_projection https://en.wikipedia.org/wiki/Eckert_II_projection

but the earth being round, you will never have a beautiful rendering everywhere. And I don't think we have to many users that would register at the poles ;-)

mlennert avatar Jun 09 '20 14:06 mlennert

Maybe the Gall-Peters could work since it is squared, need to test.

However my main concern is to have a beautiful map, not the most correct. We have plain of projection system and each system has it use, most of your proposal works really well for paper but less for web (for my point of view, and yes probably I'm influenced by Mercator too). If we find a beautiful tile server (or WMS service) of worldwide OSM data of one of above projection systems I will try with any of them ;-)

So, right now I will not work on this topic, please discuss in another ticket when community map will be merged in master

lucadelu avatar Jun 09 '20 20:06 lucadelu