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

[Ben Robbins]

>I have several issues with the current tagging system, nevertheless I
>use it to the existing standard, because at the moment I cannot come up
>with something better.

I'm trying to have a debate on the creation of something better for a few 
tags (features/borders), and the creation of a new, none replacement tag, 
for other things.  My proposals are better to the extent that without doing 
this way somethings don't work at all, but Im shore there is better yet, and 
am awaiting suggesions.

>Nodes are mathematical points, segments are mathematical lines, so
>technically these are all incorrect. However there is some default space
>usage assumed, depending on the attributes of the node/segment/way.
>So if you tag a node "cattle grid" it should be clear that the cattle
>grid is a non-dimensional thing but something that will span the entire
>width of the road at that point and occupy some length of the road as
>well. The Method of data gathering of OSM is not accurate enough to
>warrant a mapped area for something as small as a cattle grid. Or a gate
>for that matter.

I ment that gates and cattlegrids are a line, so therefore a segment, as 
drawing them as very narrow rectangles is unessesery.

For acuracy of placement the reasons against adding it acuratly are no 
reason that drawing it as an adjecent line is better than drawing it as a 
node.  There both placed realtvie to gps data and notes.

Just as a building may be a node if it hasnt been acurately mapped yet, a 
cattlegrid may be a node, but I think it should when posible be moved up to 
a line.   Just as a street is ok without a name, but when the name is found 
it should be added.

>Remember that a map is always a simplified model of the world, you have
>to leave out insignificant information for example the exact dimensions
>of a cattle grid or gate, that only matters if it limits traffic, by
>means of maximum weight, width and/or height.

There are 3 reasons I add gates in this way, and there not so that the exact 
dimensions can be seen.

1) So that it is clear what gate you are looking for when walking.  It may 
be a footgate, or a double gate, or a gate adjacent to the direction your 
walking.
2) So that the gate can lie along the hedge.  If a gate is a node, then 2 
gates would be nodes? then why not make a short hedge a node, or a long 
hedge...when do long thin feature start becoming segments?
3) They render better with no more rules than a line colour and thickness.  
Cattle grids require a few layers of rendering but are still easy to render.

Leaving out the insignificant information is different to having a tag that 
stops the insignicant infomation being added.  What is insignificant is 
debateable.  But as you said, it only matter if it limits traffic.  If true 
then a gate and cattle grid do just this, as they decrease speed, and 
access.

Ben

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