editor-layer-index add (new) strava gps traces overlay

see https://www.reddit.com/r/openstreetmap/comments/7bcsw5/stravas_heatmap_got_updated_and_can_be_used_for/, https://medium.com/strava-engineering/the-global-heatmap-now-6x-hotter-23fc01d301de?_branch_match_id=456415818991382222

josm already has this layer: https://josm.openstreetmap.de/wiki/Maps#Stravacyclingandrunningheatmap

OSM wiki page: https://wiki.openstreetmap.org/wiki/Strava#Data_Permission_-_Allowed_for_tracing.21

fixes #294

related: https://github.com/strava/iD/commit/104ae9ded4b51ab1b919273db30f58f3e5a577f0

Nov 08 '17 09:11 tyrasd

I'd like to merge this as long as we can be confident that we really are allowed to use it in all of the OpenStreetMap editors for tracing.

👋 @drewrobb - we are big fans of the Strava heatmap!.. Can you let us know if there is a license that we can link the attribution text to? (see #323, #358 for some examples of what other companies have done).

Nov 08 '17 13:11 bhousel

There are no plans to change this permission. I'm checking to see if a more explicit license could be provided for you all, but it may take some time.

Nov 09 '17 02:11 drewrobb

Yeah, it's probably best for us to wait for a proper usage permission from @strava, especially given some ambiguous statements like https://github.com/openstreetmap/iD/issues/2716#issuecomment-121759915 vs. https://twitter.com/paulmach/status/764125822441533441 in the past.

Nov 12 '17 18:11 tyrasd

So did someone tried to contact Strava? I doubt that they will craft special license for us. But e.g., in Debian, it is perfectly fine, if we get a statement from [email protected] which state the same sentence as in https://wiki.openstreetmap.org/wiki/Strava#Data_Permission_-_Allowed_for_tracing.21 and when we save the email together with email's headers it can stand as a license.

Dec 11 '17 09:12 xsuchy

FYI I've contacted Strava on Nov 23 to allow their heatmap on https://www.freemap.sk/. So far without any response. (We actually have it there already if expert mode is enabled but I plan to remove it.)

Dec 11 '17 09:12 zdila

@zdila which email you wrote to? Some general or someone personally?

Dec 11 '17 09:12 xsuchy

@xsuchy [email protected]

Dec 11 '17 09:12 zdila

Hi all, Good news: we have internally approved this usage, and are just trying to get the exact license/statement sorted out.

Dec 18 '17 20:12 drewrobb

@drewrobb any news ?

Feb 22 '18 18:02 Marc-marc-marc

Strava changed the layer to a pixelated version for lower zoom levels if you are not a Strava user yourself. Does this change anything?

Mar 14 '18 10:03 Spanholz

@tyrasd don't get mad at me, please. There was an error from my part here :-/ The maximum zoom level is 11, although Strava gives a message saying "authentication is now required for data access beyond zoom level 12, please login to strava.com and then visit /auth"

For example, we can see https://heatmap-external-b.strava.com/tiles/both/bluered/11/750/1148.png but we can't see https://heatmap-external-c.strava.com/tiles/both/bluered/12/1505/2306.png

I am sorry for this mistake.

Mar 15 '18 19:03 naoliv

Ah, I believe zoom 12 is fine, because we're using the 256px version of the tiles: https://heatmap-external-c.strava.com/tiles/both/bluered/12/1505/2306.png?px=256

Mar 16 '18 07:03 tyrasd

@drewrobb I'd love to get the heatmap into the osm editors, what's the mood like inside Strava? Anything we can do?