Openstreetmap-carto: Add rendering for historic=fort

[fqdb]

Seeing as rendering for castles is already proposed, please also add support for historic=fort.

Made a possible design for an icon as well, needs some polishing of course, anyone is free to use it if they feel the need to contribute.
fort.pdf

[kocio-pl]

I'm not sure what this icon means, so this could be tweaked, but we need 14x14 px SVG (pixel aligned) version anyway.

[kocio-pl]

This tag has 2888 uses and a wiki page:

https://wiki.openstreetmap.org/wiki/Tag%3Ahistoric%3Dfort

[kocio-pl]

What about Osmic icon design:

https://github.com/gmgeo/osmic/blob/master/tourism/fort-14.svg

Another idea would be to draw a shape of "half star", resembling the typical shape of the fort from the aerial view.

[Tomasz-W]

I though about this: http://1.bp.blogspot.com/-_xfoktodFMY/UJksjLQlDRI/AAAAAAAAAJs/EPObvzNgtsQ/s1600/VaubanPlan.jpg

Give me feedback is there a need to make an icon project with this shape.

[kocio-pl]

Something like this could work, but it might be hard at 14 px.

[Tomasz-W]

I've tried also rectangle-shaped and pentagon-shaped fort outline, but it actually didn't work. For example, five-armed shape
http://www.syler.com/SiegeWarfare/basicconcepts/imgs4BasicConcepts/StarFort01.jpg
in 14x14 gives just simple star:

[StyXman]

I made this icon for my style:

https://github.com/StyXman/elevation/blob/master/osm-carto/symbols/local/fort.svg

Do whatever you want with it, OSM gets any permisison from me :)

[kocio-pl]

Thanks. 😄 How would it look like with 14 px?

@Tomasz-W Have you tried something like this?:
https://wiki.openstreetmap.org/wiki/File:Castle_fortress.png

It wouldn't look like a simple star because the inner part is empty and the shape is stretched.

[Tomasz-W]

@kocio-pl:
(Osmic)
(@StyXman )
(@StyXman without inner part)
(star shape without inner part)

[kocio-pl]

Thanks for testing them! 3 looks quite promising for me, but it's based on rectangle instead of pentagon. Could you test pentagon with similar features?

[Tomasz-W]

I've made corner elements a little bit bigger, but it's still not working for me:

14x14:

If someone wants to tune it up, here is the Gist: https://gist.github.com/Tomasz-W/615d2766d2b7e9c4295cd11cb998c8de

[kocio-pl]

Maybe with a thin line on top instead of top feature would be better? It would be isosceles trapezoid then instead of pentagon.

[Tomasz-W]

@kocio-pl Did you mean this?

14x14:

[kocio-pl]

Yes, with thinner line on the top (to show the side where the fort connects with the city for example). It looks quite good, but I'm thinking also about other variations:

• 1 thin line on top and 4 thick walls on the bottom (instead of 3 thick walls)
• the same (3 or 4 thick walls), but with with thick elements (small thick rectangles) in the middle of thick walls (instead of on nodes/vertexes)

I hope this is more or less clear... 😃

[Tomasz-W]

I'm not sure if I understand it correctly, so I'm uploading both versions (trapezoid and pentagram) on Gist. Please tune it up on your own hand.
https://gist.github.com/Tomasz-W/0458d47f40b74c06b81888ba696cc6f1

[kocio-pl]

I think this is even better than the last one and would fit the rest of castle/palace icons (see https://github.com/gravitystorm/openstreetmap-carto/issues/744#issuecomment-362857595). Original Osmic fort icon also fits them of course, but is less readable at 14 px.
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[kocio-pl]

@Tomasz-W Thanks for your design ideas, it helped me a lot to have a reference.