[OSM-talk] The Highway tags and other junk strikes back

[guy at graviles-reynolds.org]

rQuoting Ben Robbins <ben_robbins_ at hotmail.com>:

> >Well having looked at the map on the osmarender layer, on JOSM and
> rendered
> >using osmarender with the standard tile at home feature files, I find not 
> >only does it not render pictorially,
> 
> As I said, many features dont render in the standard osmarender.
> 
> >but the information is not there for the navigation software to use i.e. 
> >where the various ways go under and over bridges, they are not aware of the
> 
> >existance of the bridges.
> 
> As I said, I have not checked over this bridge, Im shore there are faults. 
> 
> Please leave the out of the debate about what is the correct way to tag.  I
> 
> am not saying that it is.   The bridge tag isnt nessesery as there is no 
> height data for that bridge.  They are very high, and no maximum hiehgt 
> limit is stated.
> 
> >Again I would point out that features like gates, stiles, and cattle grids
> 
> >are nodes at the crossing point which when rendered will at the approprate
> 
> >zoom levels be represented by standard symbols.
> 
> Having symbols 'WILL' clog up the map.  Just having a slightly thickier 
> border line that renders along teh way tagged as a gate will not mess up the
> 
> map.

Maps are all symbols, else they would be pictures or photgraphs.

> 
> >Using your method creates a significant amount of data which adds little to
> 
> >the to the overall detail of the map, and in this instance fails to give 
> >the degree of detail that the standard tags give.
> 
> Nope.  A a gate with 1 node holds 2 bits of inforamtion.
> 
> 1) where it is rufly
> 2) that its a gate.
> 
> A gate with 3 nodes holds at least 7 bits of information
> 
> 1) where it is exaclty
> 2) how long it is
> 3) which way it faces
> 4) how it connects to what it connects to
> 5) what goes threw it
> 6) It allows the data for use in more areas outside of osm
> 7) The data needed to render it acuratly

You are neglecting the information that renders and navigation software can 
glean from the connecting segments and ways which will all give you 3, 4, 5, 
and 6. 7 is unnecessary as the renderer plots the width appropriate to the 
rendering of the way, however a width property tag can be used to hold the 
information if required.

> There is then no standard tag for the grades of track, so tracktype is 
> infintaly more full of inforamtion.
> 
> >Trying to achieve the pictorial represtation of bridge parapets using nodes
> 
> >and segments, is not the way to do it,
> 
> As I said, there is a lot of faults with it.  Please make note when I say 
> that that I mean I'm already awair of that and seeking suggestions, not un 
> helpful points that have already been observed.
> 
> >propose a symbol
> 
> Why, it renders fine as a set of parralell lines across the way.  Just 
> plonking a icon over where the gate ruffly is, is not comparable to rendered
> 
> a thicker line in the hedge where the gate is.
> 
> This is beggining to get really couter productive, and just wasting time.  
> 
> Please look at an OS  10,000 map, and you will note that borders are clearly
> 
> marked just as border are.  rivers as rivers are, roads as roads are.  Gaps
> 
> in the hedge are gaps in the hedge.  (many of which are smaller than a 
> gate).   Please don't state that its more acurate, becuase I am still just 
> talking about mapping everything relative to other features on the map.  Yet
> 
> it would seem when ever I make a point based on there method of working it 
> is seen as retarded, and using methods that are completly different to 
> theres are good.   Also methods suited to urban areas are good, and to rural
> 
> areas are not.  Well if I'm such a dum ass, can I request solutions as to 
> how to tag all these things?
> 
> There has been ownly a few really good points returned from the initial 
> email.  Mike Collinson's email for example.  Appart from that what has been
> 
> gained?  We have astablished what people want themselves, but not what 
> allows freedom to map from all different points of view.
> 
> Answer me this.
> 
> 1)  I have a track, its right of way is a footway how do I tag it.
> Answer: I can't.  the track data must go.
You tag it as a track, so that it renders as such and add a restriction tag 
indicating the it is permissive on foot.

> 2)  I have a border marked hedge.  There is a gate in it.  What is the 
> advanatage of leaveing 1 segment of the way as a hedge rarhter than calling
> 
> it a gate?
> answer: None.

When rendered the gate will not adjust its width to that of the way passing 
through it, and thus you have increased the data in the dataset for 
protentaily less rendered detail.


> 3) I drive along a track, and the track degrades to just mud, and I have to
> 
> turn around.  How do i tag this?
> annwer:  I can't.

You add a note tag and record the information and request an appropriate tag 
such as liable_flooding or laible_rutting, and when approved you update the 
node/segment and remove the note.

> 4) How do I add all that information about the bridge example?
> Anwser, I can't

you create a way the length of the viaduct with the following tags:

highway=track
foot=permissive
bridge=yes
layer=1

If the gates and cattle grids occur across way you add them to the nodes in the
way, if they are on side ways off the way then you add the ways off the main 
way just as you would a road junction and add nodes with the gate cattle grid 
tags to these connecting ways.

You note that this was an abandoned railway in a note tag and proposed an 
old_way tag, when this is approved you delete the note and add the 
old_way=abandoned_railway tag.

If you have a narrow guage railway adjacent to the track then you add a second 
way adjacent to the first, just as you would with a dual-carriage way. Whilst 
this is not pefect as it creates two adjacent bridges rather than a single 
bridge, it is the best that can be done until a method is found to join the two 
ways. On the other hand multideck bridges are easily solved by laying the ways 
on top of each other and giving them appropriate layer numbers

> 5) I'm walking threw a field looking for the footpath.  Like 99% of 
> footpaths in the country side in england there is no visual evendence of its
> 
> presence.  Would haiving a style marked on the map make it easier?.... and 
> therefore, If I no that the style is facing adjecent to me, I would be awair
> 
> that to spot it I should sway left/right so as to be able to pick it out 
> better.
> Answer, Yes

I have no idea what you mean by style, but when looking for something whilst 
navigating you use the symbols on the map which represent features you can see 
to triangulate your postion to find where you are and thus your relationship to 
the feature you are looking for. The fact that the map shows the footpath to be 
and unpaved mud track (which is what I assume you mean by style) is irrelevant 
if you cannot see it. If as is done arround here the farmer ploughs through the 
footpath then you make your best guess on the position of the path based on 
your best estimate from your triangulation.

> 6) Is it better to make quanty or qualtiy?
> well...we evedently disagree here.

It depends on what you mean by quantity and quality. If having lots of  data 
that descrides features in huge detail but using tags which will never get 
rendered is what you call quality then we do disagree.
> 
> I realy hope that andy's (backadders) new set of features will solve these 
> problems, cause discussion evedently does not.
> 
> If anyone has any way of inproving or allowing me to add this information, 
> other wise I do not wish to here there reasons why they persoanlly would not
> 
> add it.  I would be interested to here better* suggestions for the bridges 
> in particular.
> 
> *= better means better, not quicker.
> 
> The formular for making a tag that works is not:
> Easiest Way X most conveient for me = best tag.
> Its: Least Limiting x Least time consuming x Most widley usuably = best
> tag.
> 

The current bridge tag does its job well, apart from the adjacent ways in the 
same layer on the same bridge issue, it is the renderers which don't 
currently render bridges in a recgonisable fashion. It can be improved as can 
other ways with the addition of further property tags.


Guy