[OSM-talk] [BOT] [RFC]: water surfaces

[Christoph Hormann]

On Tuesday 22 March 2016, Frank Villaro-Dixon wrote:
>
> # Why ?
> Well, OSM has a quite exhaustive lakes/water surfaces database, but
> it's a complete pain to work on because:
> 	* Some non closed ways have a natural=water or a water=* tag,
> 	which makes no sense and is forbidden.
> 	* Attributes (natural, water, name, intermittent) are in the
> 	relation and in the way itself, which is anti normal form (and not
> logical).
>
> # First goal:
> First goal is quite simple. The idea is to work only on relations
> which have a natural=water .  Then, it will:
> 	* Delete natural=water from all the ways if they are NOT closed or
> 	ring 0.
> 	* delete the corresponding water=x IF the relation has the same
> 	tag

This is not going to work ('work' in the sense of turning incorrect 
information into correct information with some reasonable degree of 
reliability).

Mappers frequently map things in ambiguous ways or change existing 
mapping in ways that make it ambiguous and it is hard to decide from 
the data alone how to interpret such mapping.  A bot will not be any 
better in doing that than a human mapper and you would destroy any 
chance of actually determining the original intent of the mapper with 
such edits.

-- 
Christoph Hormann
http://www.imagico.de/