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

[Ben Robbins]

>where to you stop with the detail,

I personally would stop when the feature doesnt in anyway help a person to 
navigate.  So anything tempory or too common, or too tiny.  E.G. a mud 
puddle is tempory, the individual bars that make a cattle grid are too 
common, and stones are too tiny.   But then others may wish to map more, and 
I don't intend to stop them, just because thats not what I'm doing.

>why aren't we plotting the actual edges of each road.

Because there is common sizes. and its not limiting people from doing other 
things.

>The accuracy of the map, being as it is based in the most part on GPS 
>tracks, is not good enough to warrent the capture of details such as Cattle 
>Grids and Gates as anything other than nodes unless they are bigger than 
>the margin of error in their placement on the map.

The placement of these feature relative to reality is less inportant than 
getting them relative to the rest of the map.  The larger features are then 
close to reality.  In urban areas with small gps's the signal may not be 
strong enough to acuratly places a gate/style etc.  but in the open 
countryside areas with a larger gps (picks up weeker signals)  The placement 
of a gate is pretty acurate.  If I cross the same style many times, the 
lines of crumbs are usually extreamly close, and convert to about a range of 
1 meter in reality.  They are definatly not displaced by 8 to 10 meters, but 
rather 1 or less (unless in woodland or the obvious week signal areas.  On 
the map they are then acurate to less than a meter, relative to everything 
else, as I reference photos and allignments/angles of things.  (with almost 
no additional hasel).

Given the limitations on the accuracy of the OSM data, storing CattleGrids 
and
Gates as nodes is quite appropriate.

I definatly disagree.  A node can be placed only as acurately as 2 segments, 
but just doesnt hold the same information.   If its ture that this data is 
so far out its just misinforming the people that read the map, then nodes 
should be removed as well as segments, and just gates/border and eveything 
small alltogether.

>node:railway=viaduct

I don't use this tag.  I never tag viaduct for just the reasons you said. 
Its just a large bridge, wich the map makes clear by the size of the bridge. 
  I tag the bridge ends, and then landuse none beneth the railway/road that 
crosses it.  (it can be seen in this example)  
http://i57.photobucket.com/albums/g226/ben_robbins_/DoubleBridge-1.png



Ben

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