Add support for oneway:bicycle=-1

[PavLL]

I recently started flipping ways to adjust them to rendering footways on the right side of highway+path + segregated=yes. I've noticed however, that it's impossible to mark when the cycleway is on the right side AND oneway.

Example:
https://www.cyclosm.org/#map=20/51.13744/17.07193/cyclosm_live
https://www.openstreetmap.org/way/626720875#map=20/51.1373948/17.0718379&layers=Y

The simple solution is to have the oneway arrow point in the opposite direction when the tag oneway:bicycle=-1 oroneway=-1 is present.

[Phyks]

Hi,

Thanks for reporting this issue. First, let me emphasize that tagging for the renderer (here CyclOSM) should be avoided. Hence, as both tagging scheme are perfectly valid, I would not edit the tagging (nor leave a note) for the sole purpose of fixing the render in CyclOSM.

Then, I’m unsure about the proper tagging to use here, to properly the side of the cycleway. Given it is represented with tags on a shared (segregated) path, I’m not sure OSM tagging has a proper way to tag the side of the cycleway. On a normal road, it would be cycleway:left / cycleway:right.

One way is only conveying a notion of the direction of traffic, not on the side the way is on.

Best

[PavLL]

Hello!

It's not really tagging for the renderer as in lying for the renderer (by the definition) or using incorrect tags as this scheme is also correct and doesn't make any negative impact on routing or other renderers.

I haven't heard of any other renderers that display which side the cycleway and footway are on which made me choose mapping for this renderer since the result will be visible right away and that brings me to my next point.

There's currently no real consensus about tagging the placement of cycleways and footways on highway=path + segregated=yes. In the Netherlands it's often tagged as highway=cycleway + sidewalk=right/left which could probably be the way to go here by the look of the signs but since we don't have any accepted tagging schemes as of now (at least in Poland), I chose this tagging as it already represents something and this allows for easy semi-automatic edits for adjusting to a newer scheme in the future.

I just wanted to suggest adding this rendering feature since it would allow for my scheme to be rendered correctly and overall oneway:*=-1 is widely supported so I'm not really sure why CyclOSM doesn't, especially when there exists a tagging scheme for contraflow bicycle lanes cycleway:right=lane + cycleway:right:oneway=-1. It's really misleading when oneway=-1 is rendered the same way as oneway=yes.

Take care

[Phyks]

Ah ok got it. Thanks for the extra bits.

Relevant file for road rendering is https://github.com/cyclosm/cyclosm-cartocss-style/blob/master/roads.mss. We are only considering oneway_bicycle for bidirectional ways (or oneway:bicycle=no for OSM tagging).

The values are coming from this SQL file https://github.com/cyclosm/cyclosm-cartocss-style/blob/master/views.sql#L132 fetching from a regular osm2pgsql database. I guess the quickest edit would actually be to edit the sql file to do the « inverse tagging scheme » at sql time instead of editing OSM database.

[brainwad]

Here is another, simpler usecase for oneway:bicycle=-1. The way direction is downhill, but cycling is allowed only uphill. The way is oriented downhill presumably due to its role as part of the sled piste, so just reversing it would be disruptive.