Dit voorstel heb ik in diskussie gebracht op de tagging list, als vervolg op de diskussie hier over tree_row: https://forum.openstreetmap.org/viewtopic.php?id=61887
Het voorstel gaat niet meer specifiek over tree_row maar over spacing=* als algemeen bruikbare dimensiekenmerk vgl lengte, breedte, hoogte, diepte, elevatie. Daarom even een nieuw onderwerp gestart.
Kommentaar is welkom!
*Feature Proposal - RFC - key:spacing=
**
https://wiki.openstreetmap.org/wiki/Proposed_features/Key:spacing%3D*
According to Proposal Process:
Please discuss each proposed feature on its own discussion page.
Proposed feauture is a new key:spacing=* to indicate estimated average spacing (or it’s counterpart: density), of objects along a way or on an area.
The key is proposed as part of a rendering proposal for natural=tree_row, but it’s easy to see how it can be applied to any case where objects are more or less grouped or arranged together with a kind of regularity. In that respect spacing=* is a general purpose dimension tag like height, width, length and ele.
However, the proposed usage is explicitly non-exact: think of the spacing of trees in a tree_row or in a forest, or a barrier consisting of lengths of fence between poles. These objects are often described verbally as “very dense”, “a tree every 10 feet” or “widely spaced, about 50 meters apart”.
So the goal is to give an indication of the spatial distribution along the way or over the area, rather than an exact measurement of distances between separate actual objects. If exact positions are required for all or some of the trees in a row, these trees should be individually mapped and tagged as natural=tree. (The individual nodes may be attached to the tree_row way, which provides an easy method for aligning tree nodes within a row, but you need to tag them separately.)
That way you don’t need to worry about the dimension or shape of single objects, or that in fact some are 9 m apart and others are 11 m apart. Measurement is simple: take a sample length of the way divided by the number of sections (= #objects minus one). For people who think exact: picture a grid where every point is N m apart from it’s neighbours, then objects are placed on or near the grid points.
Tagging
spacing=N where N is average space between points representing objects (e.g. average heart-to-heart distance between trees)
units are in m unless otherwise specified (N u).
Use with natural=tree_row, natural=wood, landuse=forest, landuse=orchard, natural=scrub, barrier=hedge, or any other way or surface with more or less regularly spaced objects.
Note that the key gives spacing for the whole way or area. It is not an attribute of the objects themselves and does not imply exact placement of the objects.
Applies to
linear ways representing a loosely or densely spaced row of objects, exemplified by a tree_row. Other examples: a row of bollards, a row of stepping stones to cross a waterway, a row of street lights.
areas representing a surface loosely or densely covered with objects, exemplified by a forest or an orchard.
