Proposed features/Area-steps

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Area-relation
Status: Draft (under way)
Proposed by: Warin61
Tagging: type=area
Applies to: relation
Definition: a relation to connect pedestrian areas/ways by a step area.
Rendered as: similar to pedestrian area, use the difference between the pedestrian way and step way as an example?
Drafted on: Warin61 (talk) 23:23, 4 March 2015 (UTC)
RFC start: *
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 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

Sydney Opera House Steps -wide stairs http://www.openstreetmap.org/relation/4645750

Portugal, Lisbon, Queluz_National_Palace - inconsistent width http://www.openstreetmap.org/relation/4648262

Palacio Queluz Robillion4.JPG

http://en.wikipedia.org/wiki/Queluz_National_Palace

Reasoning

Large buildings may have a large expanse of steps at their entrance. Pedestrian areas may be linked to another pedestrian area by a large expanse of steps. Steps may have differing width from top to bottom.

These are all better tagged and rendered in a style similar to pedestrian areas

Unfortunately the use of a simple area tag (e.g. highway=area) does not identify the direction of the steps nor may it be routeable? See the tagging group for discussion on this.

Tags for the relation


Roles for the way members

  • role=lower for the lower way.
  • role=upper for the upper way.
  • optionally one or two ways with role=lateral.

This gives the direction of the steps and substitutes for the incline=up/down tag of normal steps tagged by a way.

requirements for the ways

The upper and lower ways should have the same number of nodes and point more or less in the same direction (do not have an inverse direction). They should be parallel, unless there is a different number of steps from one side to the other, or the stairs distort from top to bottom.

The upper and lower ways may have the tag tactile_paving=yes/(no)/incorrect if there is a paving on both ends of the steps that can be found with a blind person's stick.

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

The lateral ways may have the step_count=numberofsteps and/or handrail=yes/(no) tag/s for additional information.

Tags on the relation

required


optionally

  • source=* to state the source of the information.
  • step_count=23 If not consistent across the width of the steps, use the average count?
  • surface=* to sate the surface used e.g. concrete.
  • handrail=yes/no the 'steepness' of the steps in %.
  • width=* to define the width of the steps (where consistent) in metres.
  • incline=23 the 'steepness' of the steps in %.


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

  1. the proposed area-steps are completely compatible with the current data model, especially if you draw an additional way tagged as steps along the center-line of the area .