[OSM-talk] The Return of the Highway tags and other junk

[Ben Robbins]

Niko:

I agree with you post in general.

Adaption by incorrect tagging is not the best way to go I have now come to 
think.

Guy:

>I have to agree with Andy and Dirk here, as you could by not staying with 
>the agreed tagging structures find that work hard work is destroyed either 
>by someone indadvertantly deleating it as they updated the map or by an 
>automated filter purging the dataset of unreognised tags.

In that case, I shall stay doing it as segments, as I have done this many 
hundreds of times (est. 500).  The area I edit currently has knowbody else 
for about 40 miles, So confrontation is yet to be a consern.   Ideally I 
would like it never to be.   The reason here for staying with nodes seems to 
be cause its easier, not cause its better.  That doesnt stand up to any 
scutany I'm affirad.

>I also agree with Dirk that we are mapping the the planet so that it can be 
>navigated

Yes, I agree mostly, although actually we are making map data that can be 
used for anything, and how anybody wishes.

>not making a scale drawing so that we can recreate it.

A map is a to scale drawing.  If a person wants to recrete it in a 3d 
engine, then nothing should stop them.

>Coming back to gates and cattle grids, these cannot be represented by 
>anything else but a node if they are to be used by navigation software 
>reading the way as they exist as the intersection of two features such as a 
>fence crossing a road.

Yes I agree that the node has to be connected to the road, so that it can be 
read the by navagation softwere.  This doesnt mean the segments cannot also 
be there.  Its not just navagation softwere that will use maps.  People do 
to, and im shore theres other reasons.

>Thus if the fence crosses a road with a cattle grid and you make the cattle 
>grid the correct width and in the fence the road won't see it and vice 
>versa, either that or you ahve to have a single node at the crossing point 
>as you do now with four short segments radiating from it each with the tag 
>"cattle_grid=yes".

Yep.  As said in a previous message I tag the node that the road and gate 
conenct to so the softwear can pick it up.

>quickest and simplest method of recording and rendering it.

Its also quickest to make the M1 1 segment long, and have a straight line 
the entire way.  The quickest way has nothing to do with what is the best 
way.  Its quality not quantity here.   If 2 methods give the same outcome 
and 1 is quicker then thats different, but this is not an example of that.  
1 node gives less information than a segment, and is contradictory to 
reality and mapping in general.

The only time I would agree with your statment that styles fords and other 
obsticals should be tagged as nodes, is if they are a large feature and the 
name should appear sperately on the map, like the town name does to a town.

>When recording gates and cattle grids in features that run parallel to 
>roads you will obviously have to create a short track off the road and then 
>place the gate/grid node on that rather than on the road itself.

If you mean where roads split into a grid and gate, along gated roads, then 
the road needs to be split anyway, so I don't understand the problem with 
that.

I'm sorry, but I havn't heard 1 point that would make a node seem the 
logical thing to do.  I have been mapping these feautres for almost a year, 
and this is what Ive come to evaluate as the most succesfful method of 
recording data.  I would be interested to know the amount of research that 
has gone into debating the idea of sticking them as nodes.  I will stand 
corrected if proven wrong, but this really isn't gunna happen at the moment. 
  These points don't seem to stand up to much scrutany. In short If there 
isnt some rasional agreement, I will just ignore it.

Guy: For your second post check the 'Ben's bridge reply'.  There is probably 
faults with it that I would currently alter, but correct on finding, but in 
gerneral route finding should be able to find its way threw that combination 
I think.

Pictorial accuracy in maps is as inportant as the datas posible use for auto 
route finding.  Not everyone uses routefinders and maps togheter all the 
time.

Ben

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