[Talk-GB] traffic island mapping / harmful detail?

[Mike Baggaley]

I am extremely unhappy with the way a couple of members have railroaded their views and propagated these into updates on the "Land use and areas of natural land" and " How to map landuse" pages under " GB discussion on the mapping of Land Use & Land Cover" as if there has been a detailed discussion and an agreement reached. I certainly have not agreed with these views.

The comments below have been presented as if they are facts, but they seem to me to be personal views.

>1. Any stationary, physical entity can be mapped. How much detail is 
>mapped is up to the individual contributor.
This is largely true, however, the implication is also that the mapper can do this however they like. For the original point on traffic islands, I am strongly in favour of not separating carriageways where there is just a small traffic island for crossing purposes. There is a perfectly good tag that indicates that there is an island in the centre of the road. Splitting the highway does not provide any more information and makes the map confused.

>2. Landuse boundaries should not be attached to highways. The highway=* 
>tag represents the infinitesimally narrow centreline of the road. No 
>width is implied. Each renderer decides how to represent its width, or 
>use the width=* sub-tag.
In my view, the highway=* tag does not represent the centre of the road, it represents the complete highway. I accept that where fences are drawn then some landuse areas such as farmland may be better drawn up to the fence, (using common nodes with the fence). However, some of the landuse values are for non-physical things and so the edge is entirely arbitrary. For example if one side of the road is retail and the other side is residential, I consider it to be much better to align them both with the highway. This is very similar to boundaries - if a county boundary runs along a road, we do not say that the road is in neither county and draw boundary lines on both sides of the road. It is even more nonsensical to draw two landuse=residential areas, one on each side of a road with a gap between them. Quite clearly, if both sides of a road are residential areas then the area taken up by the road is also part of a residential area.

>The problem: A field boundary with a barrier=gate tag. When the boundary 
>is attached to a highway that gate also appears to be on the highway. An 
>obvious difficulty for routers.
Quite obviously the gate should be placed where it is sited (which is never on a junction). This is nothing to do with whether the landuse goes up to the highway.

Regards,
Mike