Proposal:Area-steps

Area-relation
Proposal status:	Abandoned (inactive)
Proposed by:	Warin61
Tagging:	type=area_steps
Applies to:	relation
Definition:	a relation to connect pedestrian areas/ways by a step area.
Statistics:
Rendered as:	similar to pedestrian area, use the difference between the pedestrian way and step way as an example?
Draft started:	2015-03-04
RFC start:	2019-03-29
Vote start:	*
Vote end:	*

Area-relation|Highway-steps

A large area of steps or where the upper and lower steps are significantly different from one another it may be better to map them as an area rather than a way. If they were tagged as a simple area it would not be possible to determine which is the top and which the bottom. Thus a relation is used.

A relation type=area_steps is a linear connection between two ways which defines an area between them. Generally areas are considered routable, i.e. an area-relation defines a linear connection between two, and more (contiguous), ways.

Example uses

Location	Wikipedia article	OSM	F4 Demo	OSMBuildings	Comments	Picture
Palace of Queluz, steps in Lisbon, Portugal	Palace of Queluz	Link	Link	Link	Inconsistent width, non rectangular.
Parque da Indepedência stairways, in São Paulo, Brazil	Parque da Independência	Link	Nil	Nil	Inconsistent width, non rectangular.
Theatro Municipal front stairway, in São Paulo, Brazil	Theatro Municipal	Link	Nil	Nil
Monumento à Independência surrounding stairways, in São Paulo, Brazil	Monument to the Independence of Brazil	Link	Nil	Nil	Inconsistent width, non rectangular and flows around the corners.
Sydney Opera House monumental steps, in Australia	Sydney Opera House	Link	Nil	Nil	Large rectangular area.
Sydney Town Hall / St Andrews Cathedral steps, in Australia		Link	Nil	Nil	Inconsistent number of steps, lower way is inclined.

Reasoning

This presents a way of mapping the details of steps that are not adequately represented by a simple rectangle, for example where all the sides are curved.

Competing scheme

The tag area:highway=steps has been proposed. This does not seem to provide for;

• upper/lower ways that may not be straight lines and could be inclined

• laterals that may not be straight lines

• differing number of steps from side to side

• handrails

See https://wiki.openstreetmap.org/wiki/Proposed_features/Street_area#Tagging

Mapping

As a guide, the minimum width of the step area should be greater than 5 m .. if less than 5 m consider using a simple way as the area may be too small.

Create a relation with the tags

• type=area_steps
• highway=steps

The step_count=* should be on the lateral ways, not on the relation, this provides for steps that are unequal in number across the area.

Upper and lower ways

Create 2 ways, one for the upper part of the steps, another for the lower. They should have the same number of nodes and have the same direction. Tag each way with highway=footway

Include each way in the relation with the roles;

• role=lower for the lower way.
• role=upper for the upper way.

The upper and lower ways may have the tag tactile_paving=* if there is a paving on both ends of the steps that can be found with a blind person's stick.

If the number of steps vary from one side to the other then the upper and/or lower ways may have an incline, indicate this using the tag incline=*, if only one is inclined then the other can be tagged incline=0. This should provide for any 3D mapping requirements.

The laterals or sides

Create 2 ways that connect the upper and lower ways. They should have the same number of nodes and have the same direction. Ideally they should point, or have a direction that points, upwards. Tag each way with highway=steps.

Include each way in the relation with the role lateral.

The lateral ways may have the step_count=* and/or handrail=* tag/s for additional information.

Where handrail exist inside the area, split the area so that laterals exist where the hand rails are.

Optionally

• surface=* to state the surface used e.g. concrete, or simply paved or unpaved.
• name=* to state the name of the steps.
• operator=* to state the operator of the steps.

• incline=* on the laterals. At present there is no other way to represent the steepness of the steps.

Default values

wheelchair=no is a default tag for this steps area relation.

Rendering / Display in Editors

The relation, as for any type=area, is rendered as an area above landuse and below linear ways. This relation should display similar to a pedestrian area with the distinction between the two using a similar method to that of their respective ways.

Consistency with current data model

The tags of highway=footway/highway=steps on the outer ways follows similar practice on pedestrian areas that allow routers that are not compatible with areas to use them despite this incomparability.

Having the same number of nodes on opposing ways aids renders in modelling any pattern they care to use.

The proposed area-steps is compatible with the current data model.

Discussions

Preferably on the tagging list, otherwise on the discussion page..