[Talk-GB] Vandalism in London

Lester Caine lester at lsces.co.uk
Sun Oct 5 08:49:35 UTC 2014

On 05/10/14 00:55, Frederik Ramm wrote:
> I can see both sides.
> If you want to delete something for a legitimate reason - meaning:
> because it just isn't there on the ground - then why should you care in
> how many relations it is - if it isn't there then it ought to be
> deleted, period, and you'll be thankful if the editor takes care of
> ensuring referential integrity of relations for you.

The fundamental problem here is this concept of 'delete' taking
priority. Something I've moaned about before. Yes there are legitimate
reasons why 'delete' may be an appropriate action, but it quite simply
currently there are no protections to prevent novice mappers using it as
an easy way of mapping. There SHOULD be at least a two stage step to
delete, and more important the historic aspects SHOULD still be
respected a little more. That a road has moved due to an improvement
scheme is an historic fact, and the old road's data is still valid and
while for some it's trash, for others of us it is still a valid element
in a view of the data at an earlier time. I still find the relations
area ill-conceived as maintaining integrity does require a lot more
manual work, and I think there is a lot of room for improvement when it
comes to things like routing data and maintaining closed boundaries?
That iD breaks things is a fact that needs to be addressed and perhaps
it's about time it's edits where they do delete anything relation based
should be ring fenced and require a second opinion before they can be
completed? But I think what is actually needed is a proper review of the
'micro/macro' mapping situation again. Where a 'way' exists that joins
to locations together is a macro element that may well consist of many
parallel and interlinked objects, which a relation tries to correlate?
But if there was a constraint on the relation saying that something is a
closed loop, such as a boundary, or a defined link between two points,
then when an element needed to maintain that constraint is deleted it
can be flagged better? If the break is due to some micro-mapping change
such as perhaps breaking a way to add a new speed limit, the API should
know that the extra new way needs to be added to the relation
automatically? If a section of the way is deleted and redrawn then there
should be a block on the deleted element being removed until the
'damage' is repaired. Something that JOSM at least tries to help with,
but iD ignores?

And if the deletion is due to a road improvement scheme the data should
simply be correctly marked with an end date rather than being deleted at
all, but keeping the correct historic view of the relation is something
that needs to be considered as well! It is in the change log but perhaps
not in the right format to be accessed easily in future? :(

Lester Caine - G8HFL
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