Re: [Tagging] Tagging of topographic areas with a name

2013-08-23 Thread Yuri D'Elia
On 08/19/2013 11:51 PM, Masi Master wrote:
 This is a bit away from the new valley  mountain discus, but has a
 connection to the first mail.
 Tagging should be thought-out with possible examples, if we don't want
 to change the tagging or live with a bad tagging.

Another example I had just yesterday was a lake called Seebergsee in
the alps.

The lake itself is comprised of a very small persistent lake which is
well delimited, and a marsh which is filled with water during 1/3 of the
year as the snow melts.

Independently of the tagging (which is well delimited in this case), the
name refers to the lake _and_ the marsh.

Maybe there's some waterway relation magic for this specific case, but
I'd rather use some consistent topological naming of areas also for
these cases.



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Re: [Tagging] Tagging of topographic areas with a name

2013-08-19 Thread Martin Koppenhoefer


Il giorno 18/ago/2013, alle ore 15:54, Yuri D'Elia 
wav...@users.sourceforge.net ha scritto:

 Just for clarity, I was really hoping to find an already-established
 tagging scheme for these features (named topological areas, valleys),
 and bringing up the schemes I found in several other places rather than
 trying to overcomplicate things.


what is already there is mostly in the natural namespace or sometimes tagged as 
place=locality (mostly on nodes). Our data model (scale, db) is not suited very 
well for topographic areas (there are usually more low scale). A better 
solution would IMHO be to have multilingual shape files for this kind of data 
and mix them at render time

cheers,
Martin
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Re: [Tagging] Tagging of topographic areas with a name

2013-08-19 Thread Martin Koppenhoefer


Il giorno 18/ago/2013, alle ore 17:29, Craig Wallace craig...@fastmail.fm ha 
scritto:

 This is already done for ridges, with natural=ridge. 
 http://wiki.openstreetmap.org/wiki/Tag:natural%3Dridge
 It is used a bit. Not sure if any renderers show it.


ridges are linear


 
 I think something similar could be used for valleys.


-1, valleys are areas


 
 It won't really work for mountain ranges, as they are often not linear.


could they be relations with summits and ridges?


cheers,
Martin
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Re: [Tagging] Tagging of topographic areas with a name

2013-08-19 Thread Martin Koppenhoefer


Il giorno 18/ago/2013, alle ore 17:54, Christian Müller cmu...@gmx.de ha 
scritto:

 The term boundary does not make any implication on it's width.


it has no width at all, it is a line



  A boundary may be defined on a nanometer, meter or kilometer scale.


what doesn't say anything about a width, but tells you the grade of detail to 
expect


  Even political boundaries are in reality many meters wide, e.g. to defend 
 them.  Think of the historical inner german border for example.


The Berlin Wall (the 2 walls and the space in between) was entirely on eastern 
German territory and wasn't the actual boundary (which was a few meters before 
the actual wall)


cheers,
Martin
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Re: [Tagging] Tagging of topographic areas with a name

2013-08-19 Thread Christian Müller
Il giorno 18/ago/2013, alle ore 17:54, Christian Müller cmu...@gmx.de ha 
scritto:
 The term boundary does not make any implication on it's width.
 it has no width at all, it is a line

-1.  It may be _represented_ by a line, as declared by an entity.  Even though 
the boundaries of territories may be declared using lines, you have to keep in 
mind that this is an abstraction.  Often these lines just represent the center 
of a _buffer_ around a core area. 

A line of zero width is an abstraction for a boundary.  Again, the term 
boundary does not make any implication on it's width.  It may be represented by 
a line with zero width, but may just as well be by an area with constant or 
variing width as you walk around the core area to be defined.

Of course, if you use an (buffer) area for definition, you may very well start 
to realize the recursive nature in trying to define a boundary - as you wonder 
about how to represent the boundary of the buffer area.  Should it be a line of 
zero width or, again, be a buffer area? [..]

This especially holds true for natural regions that originally might just have 
been declared by a mere description in a natural language.  However you will 
find examples of this in other fields - take Bohr's model of the atom.  The 
probability for an electron to reside in one shell won't change abruptly on the 
shells boundary abstracted by a sphere's surface of zero width.  These shells 
are zones.

Back to our matter of _topographic areas_ you will find a note about the 
abstract nature of boundaries elsewhere, e.g. in the article
  http://en.wikipedia.org/wiki/Boundaries_in_landscape_history

If you focus on the last part of the second sentence, quote
  the boundary can often be seen by differences in land use on either side.

you may find that the concept of natural boundaries is about finding similar 
features on one of two adjacent sides, separating them from similar-found 
features on the other.  So a boundary separates one side from the other, or 
connects one side to the other, depending on the glass being half empty or half 
full.

The criteria taken into account when grouping similar features to form 
undivided areas and the precision of measurement together determine how sharp 
or fuzzy this boundary between areas will be.  To simplify the fact that in 
practice you will never find a zero width boundary you could also substitute: A 
boundary is an area between areas.

When institutions define natural regions you will sometimes see this reflected 
in coined terms such as boundary zone.  These are crippling a sharp, 
mathematically used, zero width expressed boundary into what effectively is an 
area boundary, since it's not feasible to narrow down a natural area, i.e. zone 
to a point where a zero-width line abstraction comes to mind naturally.


 Even political boundaries are in reality many meters wide, e.g. to defend 
 them. Think of the historical inner german border for example.
 The Berlin Wall (the 2 walls and the space in between) was entirely on 
 eastern German territory and
 wasn't the actual boundary (which was a few meters before the actual wall)

It all depends on what exactly you refer to.  In day-to-day life you should not 
find too many people that think of a zero width line abstraction when talking 
about this histo-political boundary.  It may have been at the time it was 
declared, but there are other people having more insight on this.  And it may 
have been a bad example, yes.


Greetings

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Re: [Tagging] Tagging of topographic areas with a name

2013-08-19 Thread Bryce Nesbitt
On Sun, Aug 18, 2013 at 8:17 AM, Volker Schmidt vosc...@gmail.com wrote:

 At the risk that this is mapping for the renderer, but what
 Wolfgang proposes is exactly how it is done on traditional paper maps. It
 gives you the possibility to label some loosely defined entity, by creating
 some labelling along a non visible way. However, there is a serious
 complication in this, which consists in the fact that you would have to
 assign some kind of importance to the label to allow the renderer to
 decide at which zoom levels to show the labelling and with what kind  of
 visibility.


A traditional paper mapper makes visibility decisions, which automated
agents have more trouble with.
For example:  imagine three ridges, all named, all about the same length.
Which should show at low zoom?
A cartographer might know that the local residents refer to the third ridge
most often, and that it is somehow more important.

An automated agent could try: but the data is likely outside of OSM.
 Should it google for the name and count the hits?
Send an email to nearby mappers?
---

Some manual tweaking of the importance has wide applicability in OSM,
despite the obvious disagreements on the exact rankings/
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Re: [Tagging] Tagging of topographic areas with a name

2013-08-19 Thread Masi Master

Am 17.08.2013, 17:13 Uhr, schrieb fly lowfligh...@googlemail.com:


On 16.08.2013 19:05, Masi Master wrote:

The problem is, that multipolygon don't work in 2 cases:
- The areas touch each other.
- The areas are multipolygons. A multipolygon as a member in a other
multipolygon is not allowed.

Either we allowed this, or we need any relation which collect these
things...


You can always split the ways and use the parts tagged with outer/inner


I thought about a lake, which has some parts with a own name.
If we need an additional multipolygon for the whole lake, first we had to  
cut off the island twice (in the lake and the sub-lake), and second we can  
not tag both lakes with natural water, because we don't want to add more  
water to the database than exists.


So in my eyes, we need both (upper) features for multipolygons. It prevent  
errors if an island is not cut off twice by multipolygon:inner. And the  
whole lake can be combined by the sub-lakes, without the natural=water tag.


This is a bit away from the new valley  mountain discus, but has a  
connection to the first mail.
Tagging should be thought-out with possible examples, if we don't want to  
change the tagging or live with a bad tagging.


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Re: [Tagging] Tagging of topographic areas with a name

2013-08-18 Thread Yuri D'Elia
On 08/17/2013 05:47 PM, Wolfgang Zenker wrote:
 * fly lowfligh...@googlemail.com [130817 17:13]:
 On 16.08.2013 19:05, Masi Master wrote:
 Hmm, I'm not sure that boundary is the right tag. Isn't it a border, and
 not an area?
 
 Boundaries describe an area but you are right that they are not really
 boundaries, especially if the border lines are not clearly defined
 [..]
 
 I'm under the impression this discussion is leading to ever more complicated
 ideas, due to the problem that the features we want to name on the map
 are not really clearly defined areas.

Just for clarity, I was really hoping to find an already-established
tagging scheme for these features (named topological areas, valleys),
and bringing up the schemes I found in several other places rather than
trying to overcomplicate things.

While I agree that rendering should follow tagging, I also go by the
idea that as long as the scheme is consistent, one could switch to an
improved one later quickly enough.

Also, the people involved with rendering should have a pretty decent
overview of how the tags are actually used, corner cases and the
limitations involved. This is as important as tagging itself IMHO (I was
rendering navteq data in the past, so I value a lot input from software
implementations).

I'm not sure if this list is followed by people involved with
styling/rendering OSM data itself? (please tell me if some other list
might be more appropriate).



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Re: [Tagging] Tagging of topographic areas with a name

2013-08-18 Thread Volker Schmidt
At the risk that this is mapping for the renderer, but what
Wolfgang proposes is exactly how it is done on traditional paper maps. It
gives you the possibility to label some loosely defined entity, by creating
some labelling along a non visible way.
However, there is a serious complication in this, which consists in the
fact that you would have to assign some kind of importance to the label
to allow the renderer to decide at which zoom levels to show the labelling
and with what kind  of visibility. So, if we want to go this way, the thing
is not quite as simple. We would need to define something like the
equivalent of admin_level, may be an importance_level.
Just my 2 cents - I admit this is not thought through in any way, but ...


On 17 August 2013 17:47, Wolfgang Zenker wolfg...@lyxys.ka.sub.org wrote:

 Hi,

 * fly lowfligh...@googlemail.com [130817 17:13]:
  On 16.08.2013 19:05, Masi Master wrote:
  Hmm, I'm not sure that boundary is the right tag. Isn't it a border, and
  not an area?

  Boundaries describe an area but you are right that they are not really
  boundaries, especially if the border lines are not clearly defined
  [..]

 I'm under the impression this discussion is leading to ever more
 complicated
 ideas, due to the problem that the features we want to name on the map
 are not really clearly defined areas.

 Maybe we should try a completely different approach. We could draw
 a way along the approximate center line of the feature and tag it
 with name=*, topo_feature=mountain_range|ridge|valley|...
 A renderer that wants to display the name should draw it along that
 way with the length of the way giving a hint about the size of the
 feature.

 Wolfgang

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Re: [Tagging] Tagging of topographic areas with a name

2013-08-18 Thread Craig Wallace

On 2013-08-17 16:47, Wolfgang Zenker wrote:


Maybe we should try a completely different approach. We could draw
a way along the approximate center line of the feature and tag it
with name=*, topo_feature=mountain_range|ridge|valley|...
A renderer that wants to display the name should draw it along that
way with the length of the way giving a hint about the size of the
feature.


This is already done for ridges, with natural=ridge. 
http://wiki.openstreetmap.org/wiki/Tag:natural%3Dridge

It is used a bit. Not sure if any renderers show it.

I think something similar could be used for valleys.

It won't really work for mountain ranges, as they are often not linear.

Craig

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Re: [Tagging] Tagging of topographic areas with a name

2013-08-17 Thread fly
On 16.08.2013 19:05, Masi Master wrote:
 Hmm, I'm not sure that boundary is the right tag. Isn't it a border, and
 not an area?

Boundaries describe an area but you are right that they are not really
boundaries, especially if the border lines are not clearly defined

 The problem is, that multipolygon don't work in 2 cases:
 - The areas touch each other.
 - The areas are multipolygons. A multipolygon as a member in a other
 multipolygon is not allowed.
 
 Either we allowed this, or we need any relation which collect these
 things...

You can always split the ways and use the parts tagged with outer/inner

 (What the renderer do, is not primary. If we find a good tagging, the
 renderer should follow the tagging, not backwards.)

Forget the renderer but think about all software. It is probably easier
to use an established system with one more subtag than clone the system
and use a new type and at least admin_centre would be useful.

Cu fly



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Re: [Tagging] Tagging of topographic areas with a name

2013-08-17 Thread Wolfgang Zenker
Hi,

* fly lowfligh...@googlemail.com [130817 17:13]:
 On 16.08.2013 19:05, Masi Master wrote:
 Hmm, I'm not sure that boundary is the right tag. Isn't it a border, and
 not an area?

 Boundaries describe an area but you are right that they are not really
 boundaries, especially if the border lines are not clearly defined
 [..]

I'm under the impression this discussion is leading to ever more complicated
ideas, due to the problem that the features we want to name on the map
are not really clearly defined areas.

Maybe we should try a completely different approach. We could draw
a way along the approximate center line of the feature and tag it
with name=*, topo_feature=mountain_range|ridge|valley|...
A renderer that wants to display the name should draw it along that
way with the length of the way giving a hint about the size of the
feature.

Wolfgang

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Re: [Tagging] Tagging of topographic areas with a name

2013-08-17 Thread Pieren
On Sat, Aug 17, 2013 at 5:47 PM, Wolfgang Zenker
wolfg...@lyxys.ka.sub.org wrote:

 I'm under the impression this discussion is leading to ever more complicated
 ideas, due to the problem that the features we want to name on the map
 are not really clearly defined areas.
+1

 Maybe we should try a completely different approach. We could draw
 a way along the approximate center line of the feature

or we could simply admit that OSM project is currently unable to map
such big features with fuzzy borders...

Pieren

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Re: [Tagging] Tagging of topographic areas with a name

2013-08-17 Thread Martin Koppenhoefer
2013/8/17 Pieren pier...@gmail.com

  Maybe we should try a completely different approach. We could draw
  a way along the approximate center line of the feature

 or we could simply admit that OSM project is currently unable to map
 such big features with fuzzy borders...



+1, a way is surely not a good representation.

cheers,
Martin
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Re: [Tagging] Tagging of topographic areas with a name

2013-08-13 Thread Phil! Gold
* Friedrich Volkmann b...@volki.at [2013-08-09 07:28 +0200]:
 I also dislike the suggested special member roles: The positioning
 of the label depends on the font size, the free space, the map
 section and zoom level etc. and should therefore be determined by
 the renderer.

I tend to think of label nodes as hints for the renderer that provide it
with information it cannot derive on its own.  The canonical example, I
think, is a town where it makes sense to place the label over the town
center, which residents of the place can usually identify easily, but
which may not necessarily match the geometric center (or centroid) of the
town's border.

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Re: [Tagging] Tagging of topographic areas with a name

2013-08-13 Thread Bryce Nesbitt
On Tue, Aug 13, 2013 at 11:15 AM, Phil! Gold phi...@pobox.com wrote:

 I tend to think of label nodes as hints for the renderer that provide it
 with information it cannot derive on its own.  The canonical example, I
 think, is a town where it makes sense to place the label over the town
 center, which residents of the place can usually identify easily, but
 which may not necessarily match the geometric center (or centroid) of the
 town's border.


+1

And a trickier example:  a camp complex with four buildings, all with a
name=.
At lower zoom levels which building's name should show?  The rendering
needs a hint to know what name=Camp Office is of broader interest than
name=Maintenance Shed.
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Re: [Tagging] Tagging of topographic areas with a name

2013-08-12 Thread Yuri D'Elia
On 08/08/2013 11:54 PM, Martin Koppenhoefer wrote:
 I guess in this case I can simply re-use the geometry in a new relation
 with the proper valley name with type=multipolygon, place=region,
 region:type=valley?
 
 I'd use type=multipolygon natural=valley

I'm still not satisfied with type=multipolygon:

http://wiki.openstreetmap.org/wiki/Multipolygon#Detailed_tagging

specifically:

* The relation has tags:
  Use the relation tagging. Ignore anything on the ways.

However, this is not what should happen for a lake group where each lake
name is independent (ie, the group is just a topological feature). And,
as I said before, unnamed lakes should not inherit the name of the group.

After re-reading the whole thread, I tend to agree with fly more, as a
boundary type seem to be much more appropriate:

type=boundary
boundary=topologic
natural=water
name=lake group name

the boundary relation has the advantage of not requiring a fake polygon
(as opposed to place=locality).

I have two examples of type=multipolygon which I introduced:

http://www.openstreetmap.org/browse/relation/3126464
http://www.openstreetmap.org/browse/relation/3126459

whole type=multipolygon relation simply broke the rendering (but
renderers here seem to be compliant).



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Re: [Tagging] Tagging of topographic areas with a name

2013-08-10 Thread fly
On 09.08.2013 07:34, Friedrich Volkmann wrote:
 On 08.08.2013 21:15, fly wrote:
 On 08.08.2013 01:24, Pieren wrote:
 I really hate type=collection. One of the worst idea in OSM. All
 relations are collections.

 +100

 Especially, if you read: Relations are not meant to be used as
 collections
 
 It is interesting that you agree by +100 although your reason is the
 negation of Pieren's reason.

Not at all but the meaning is different:

* All relations are some kind of collection caused by design.
* You should not use a relation to simply collect/group some objects
together. This means I do not need a relation for all German Autobahns
or all bus lines in a city or even all valleys of a mountain group. Even
site-relations should only be used if it does not work without it
(several non-connected areas).

Another reason I am against this collection is that you might not always
have the same borders with the subgroup (valleys). You will need to
create a new (sub)-relation to get only part of it into your collection.

Please use boundaries and not multipolygons !

cu
fly


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Re: [Tagging] Tagging of topographic areas with a name

2013-08-10 Thread Martin Koppenhoefer


Il giorno 10/ago/2013, alle ore 18:17, fly lowfligh...@googlemail.com ha 
scritto:

 Please use boundaries and not multipolygons !


for valleys?? 
boundaries are linear objects (generally delimiting areas), multipolygons are 
areas

cheers,
Martin
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Re: [Tagging] Tagging of topographic areas with a name

2013-08-08 Thread Friedrich Volkmann

On 08.08.2013 01:24, Pieren wrote:

On Wed, Aug 7, 2013 at 10:19 PM, Friedrich Volkmannb...@volki.at  wrote:

It should rather be a type=collection relation.


I really hate type=collection. One of the worst idea in OSM. All
relations are collections.


At least it is semantically correct, while type=site relations are often 
used for features on multiple sites.


You can think of type=collection as an abbreviation of 
type=bare_and_general_collection. All other relations have special members 
(e.g. inner/outer in multipolygons) or at least special meanings (type=route).


type=cluster has also been suggested. I would be ok with it, but it would 
require a proposal to make it more popular.


--
Friedrich K. Volkmann   http://www.volki.at/
Adr.: Davidgasse 76-80/14/10, 1100 Wien, Austria

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Re: [Tagging] Tagging of topographic areas with a name

2013-08-08 Thread Yuri D'Elia
On 08/07/2013 10:19 PM, Friedrich Volkmann wrote:
 On 06.08.2013 15:51, Yuri D'Elia wrote:
 http://www.openstreetmap.org/#map=14/45.2466/6.0866

 which has been tagged with a multipoligon relation.
 Unfortunately, the relation has some problems:

 - not rendered anywhere?
 
 This is a super-relation, with other relations as members. This is not
 allowed for multipolygon relations. It should rather be a
 type=collection relation. This is how water areas such as riverbanks use
 to be joined, and I use collection relations for sets of rocks etc. too.
 Don't expect dumb renderers like Mapnik to render superrelations, though.

Very good explaination.

 It seems to me that the closest tagging scheme might be a loose area
 with place=locality. Would that be a good idea?
 
 That depends on what the name belongs to. If it's the name of a lake,
 forest, or other physical feature, place=* would be just wrong.

After reading all the replies, it seems that if a group of lakes has a
name, I would probably use either a multipolygon (if feasible) or a
super-relation, with the appropriate natural tag.

Though for places without actual physical attributes, place=location
sounds reasonable.

It also looks like that the ThunderForest maps are correctly rendering
the place=location tag:

  http://www.opencyclemap.org/?zoom=11lat=46.5215lon=11.37205layers=000B

I will now convert this group to a super-relation.

My issue with normal multipolygons is also that smaller, unnamed lakes
inherit the name of the relation, which is incorrect.

 These proposals are somewhat obsolete, as natural=* has widely been
 accepted as the key for all geomorphological features. See
 http://wiki.openstreetmap.org/wiki/Key:natural, group 3. A valley is
 just the complement of a ridge or arete. Just draw a line along the
 valley and tag it with natural=valley.

I still have doubts about this. For the valley I'm speaking about the
whole region, which is an area.

By looking at your next pointer (about mountain_range), it looks like I
can follow the same scheme and use region_type=valley as a subtype.

 Similarly, we have areas for entire mountain groups, which are
 fundamental for a topographic map in the alps. Again, the boundaries of
 such areas are not so important, but it's mostly used as an indication
 for the name placement.
 
 natural=mountain_range is already in use for the Alps. The mountain
 groups within the Eastern Alps are tagged place=region, see the members
 of relation 2113486.

This has been incredibly helpful!

I assume this is the data that is being used to render the topographic
map at dianacht.de? (http://geo.dianacht.de/topo/)



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Re: [Tagging] Tagging of topographic areas with a name

2013-08-08 Thread Martin Koppenhoefer


Il giorno 08/ago/2013, alle ore 17:47, Yuri D'Elia 
wav...@users.sourceforge.net ha scritto:

 Though for places without actual physical attributes, place=location
 sounds reasonable.


thing is that place=locality is very generic, you don't get additional 
information what the name refers to, especially if tagged on a node

cheers,
Martin
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Re: [Tagging] Tagging of topographic areas with a name

2013-08-08 Thread Yuri D'Elia
On 08/08/2013 07:15 PM, Martin Koppenhoefer wrote:
 Though for places without actual physical attributes, place=location
 sounds reasonable.
 
 thing is that place=locality is very generic, you don't get additional 
 information what the name refers to, especially if tagged on a node

Understood.



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Re: [Tagging] Tagging of topographic areas with a name

2013-08-08 Thread Yuri D'Elia
On 08/08/2013 08:56 AM, Friedrich Volkmann wrote:
 On 08.08.2013 01:24, Pieren wrote:
 On Wed, Aug 7, 2013 at 10:19 PM, Friedrich
 Volkmannb...@volki.at  wrote:
 It should rather be a type=collection relation.

 I really hate type=collection. One of the worst idea in OSM. All
 relations are collections.
 
 At least it is semantically correct, while type=site relations are often
 used for features on multiple sites.
 
 You can think of type=collection as an abbreviation of
 type=bare_and_general_collection. All other relations have special
 members (e.g. inner/outer in multipolygons) or at least special meanings
 (type=route).
 
 type=cluster has also been suggested. I would be ok with it, but it
 would require a proposal to make it more popular.
 

What about type=site with the appropriate natural tag?

https://wiki.openstreetmap.org/wiki/Relations/Proposed/Site

I was just looking at the wiki, and type=collection seems to be pretty
frowned upon.



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Re: [Tagging] Tagging of topographic areas with a name

2013-08-08 Thread Yuri D'Elia
On 08/07/2013 10:19 PM, Friedrich Volkmann wrote:
 Similarly, we have areas for entire mountain groups, which are
 fundamental for a topographic map in the alps. Again, the boundaries of
 such areas are not so important, but it's mostly used as an indication
 for the name placement.
 
 natural=mountain_range is already in use for the Alps. The mountain
 groups within the Eastern Alps are tagged place=region, see the members
 of relation 2113486.

So, I was looking about using place=region for valleys.

At least for the valleys I was looking into, it seems that Italy already
has a boundary=administrative multipolygon for most of them, although
in rare cases some natural features are more detailed than the
administrative boundary.

Let's take this for example:

http://www.openstreetmap.org/browse/relation/47143

where the administrative boundary matches exactly with the actual valley.

I guess in this case I can simply re-use the geometry in a new relation
with the proper valley name with type=multipolygon, place=region,
region:type=valley?



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Re: [Tagging] Tagging of topographic areas with a name

2013-08-08 Thread fly
On 08.08.2013 01:24, Pieren wrote:
 On Wed, Aug 7, 2013 at 10:19 PM, Friedrich Volkmann b...@volki.at wrote:
 It should rather be a type=collection relation.
 
 I really hate type=collection. One of the worst idea in OSM. All
 relations are collections.

+100

Especially, if you read: Relations are not meant to be used as collections

cu
fly

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Re: [Tagging] Tagging of topographic areas with a name

2013-08-08 Thread fly
On 06.08.2013 19:25, Yuri D'Elia wrote:

 The message from fly, about about boundary=topologic/geographic though
 would solve nicely valleys, mountain groups _and_ other topographic
 features under a single umbrella, and it's quite easy to achieve.
 
 to fly: Is this some form of official proposal?

As official as this mailing list. I will not have the time nor power to
make it an proposal but you are welcome to take my idea.

Using boundaries has a lot of advantages as there are already well
establish super-relations and labels to describe the capital of the area
if existing.

cu
fly


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Re: [Tagging] Tagging of topographic areas with a name

2013-08-08 Thread Martin Koppenhoefer


Il giorno 08/ago/2013, alle ore 20:45, Yuri D'Elia 
wav...@users.sourceforge.net ha scritto:

 I guess in this case I can simply re-use the geometry in a new relation
 with the proper valley name with type=multipolygon, place=region,
 region:type=valley?


I'd use type=multipolygon natural=valley

cheers,
Martin
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Re: [Tagging] Tagging of topographic areas with a name

2013-08-08 Thread Friedrich Volkmann

On 08.08.2013 19:39, Yuri D'Elia wrote:

At least it is semantically correct, while type=site relations are often
used for features on multiple sites.

[...]

What about type=site with the appropriate natural tag?

https://wiki.openstreetmap.org/wiki/Relations/Proposed/Site


See my paragraph that I quoted on top. Now in more detail: The proposal says:
If all the elements contained within an area (the perimeter) belong to the 
site, and no elements of the site exist outside the area, then it is 
inappropriate to use this relation.
That means that the relation should only be used for elements in differing 
locations, i.e. NOT on one site. It is absurd to call that a site relation.


I also dislike the suggested special member roles: The positioning of the 
label depends on the font size, the free space, the map section and zoom 
level etc. and should therefore be determined by the renderer. The perimeter 
is implied by the other members. The entrance is implied by the entrance=* 
node(s) on the perimeter.


All in all, I see nothing good in the type=site proposal.


I was just looking at the wiki, and type=collection seems to be pretty
frowned upon.


I don't know about the frowning. If you just look at pros and cons, you will 
prefer type=collection over type=site.


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Re: [Tagging] Tagging of topographic areas with a name

2013-08-08 Thread Friedrich Volkmann

On 08.08.2013 21:15, fly wrote:

On 08.08.2013 01:24, Pieren wrote:

I really hate type=collection. One of the worst idea in OSM. All
relations are collections.


+100

Especially, if you read: Relations are not meant to be used as collections


It is interesting that you agree by +100 although your reason is the 
negation of Pieren's reason.


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Re: [Tagging] Tagging of topographic areas with a name

2013-08-07 Thread Eugene Alvin Villar
On Tue, Aug 6, 2013 at 11:19 PM, fly lowfligh...@googlemail.com wrote:

 On 06.08.2013 16:27, Yuri D'Elia wrote:
   Fortunately, the boundaries of the area are not important in themselves.
  Nobody renders valley or mountain group borders. But we *do* use such
  boundaries for name placement.

 I think the best would be to invent a new boundary type.

 boundary=topologic or geographic
 topologic/geographic=valley/cordillera/mountain_range/region

 and some ranking for the categories

 As the borders are often not that clear and also not that important they
 should not be rendered and do not have to be that exact but for
 rendering names like in [1] we need them.


This solution can also apply to bodies of water that are not whole lakes or
rivers. We currently (I think) do not tag the extent (even if fuzzy) of
seas, bays, inlets, coves, fjords, and the like.

The International Hydrographic Organization has published a document
delimiting the oceans and major seas of the world: Limits of Oceans 
Seas, Special Publication No. 23. Smaller bodies of water may be delimited
by national governments.

The natural=coastline can be used to build up area relations of the
proposed type=topologic/geography and extra ways can be used elsewhere.
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Re: [Tagging] Tagging of topographic areas with a name

2013-08-07 Thread Martin Koppenhoefer


Il giorno 07/ago/2013, alle ore 10:00, Eugene Alvin Villar sea...@gmail.com 
ha scritto:

 This solution can also apply to bodies of water that are not whole lakes or 
 rivers. We currently (I think) do not tag the extent (even if fuzzy) of seas, 
 bays, inlets, coves, fjords, and the like.


don't know about the rest, but there are 3 natural=bay in the db 
http://taginfo.openstreetmap.org/search?q=natural%3Dbay

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Re: [Tagging] Tagging of topographic areas with a name

2013-08-07 Thread Geir Ove Myhr
On Wed, Aug 7, 2013 at 10:42 AM, Martin Koppenhoefer
dieterdre...@gmail.com wrote:
 Il giorno 07/ago/2013, alle ore 10:00, Eugene Alvin Villar
 sea...@gmail.com ha scritto:

  We currently (I think) do not tag the ***extent*** (even if fuzzy) of
  seas, bays, inlets, coves, fjords, and the like.

 don't know about the rest, but there are 3 natural=bay in the db
 http://taginfo.openstreetmap.org/search?q=natural%3Dbay

... and 29000 of them are nodes, i.e. no extent.

http://taginfo.openstreetmap.org/tags/natural=bay

Geir Ove

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Re: [Tagging] Tagging of topographic areas with a name

2013-08-07 Thread Janko Mihelić
The best way I can think of for drawing oceans, is to put a tag on all
natural=coastline ways that are bordering it. Something like
ocean:name:en=Atlantic ocean.

Janko
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Re: [Tagging] Tagging of topographic areas with a name

2013-08-07 Thread Martin Koppenhoefer
2013/8/7 Janko Mihelić jan...@gmail.com

 The best way I can think of for drawing oceans, is to put a tag on all
 natural=coastline ways that are bordering it. Something like
 ocean:name:en=Atlantic ocean.



If you look closely onto this you'll see that there are not only the oceans
but a whole hierarchy of  names seas and oceans and parts of them, so there
is not only one name per coastline but a lot of them. Dependent on the
scale of your map you'll emphasize different ones and omit others.

Cheers,
Martin
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Re: [Tagging] Tagging of topographic areas with a name

2013-08-07 Thread Janko Mihelić
2013/8/7 Martin Koppenhoefer dieterdre...@gmail.com



 If you look closely onto this you'll see that there are not only the
 oceans but a whole hierarchy of  names seas and oceans and parts of them,
 so there is not only one name per coastline but a lot of them. Dependent on
 the scale of your map you'll emphasize different ones and omit others.


+1

That's why I chose ocean, because I'm sure there's only one on each
coastline. There can be more than one bay or sea, like the Mediterranean
and the Adriatic sea. Relations are not possible, there's too much ways, so
the only thing I can think of are tags like
sea_level_1:name:en=Mediterranean sea, sea_level_2:name:en=Adriatic sea.

Janko
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Re: [Tagging] Tagging of topographic areas with a name

2013-08-07 Thread Friedrich Volkmann

On 06.08.2013 15:51, Yuri D'Elia wrote:

http://www.openstreetmap.org/#map=14/45.2466/6.0866

which has been tagged with a multipoligon relation.
Unfortunately, the relation has some problems:

- not rendered anywhere?


This is a super-relation, with other relations as members. This is not 
allowed for multipolygon relations. It should rather be a type=collection 
relation. This is how water areas such as riverbanks use to be joined, and I 
use collection relations for sets of rocks etc. too. Don't expect dumb 
renderers like Mapnik to render superrelations, though.



It seems to me that the closest tagging scheme might be a loose area
with place=locality. Would that be a good idea?


That depends on what the name belongs to. If it's the name of a lake, 
forest, or other physical feature, place=* would be just wrong.



I saw several proposed tags in the wiki:

http://wiki.openstreetmap.org/wiki/Relations/Proposed/Region
http://wiki.openstreetmap.org/wiki/Proposed_features/Valley

but not really an official tagging scheme. Valley names are very
important features for a topographic map.


These proposals are somewhat obsolete, as natural=* has widely been accepted 
as the key for all geomorphological features. See 
http://wiki.openstreetmap.org/wiki/Key:natural, group 3. A valley is just 
the complement of a ridge or arete. Just draw a line along the valley and 
tag it with natural=valley.



Similarly, we have areas for entire mountain groups, which are
fundamental for a topographic map in the alps. Again, the boundaries of
such areas are not so important, but it's mostly used as an indication
for the name placement.


natural=mountain_range is already in use for the Alps. The mountain groups 
within the Eastern Alps are tagged place=region, see the members of relation 
2113486.


--
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Adr.: Davidgasse 76-80/14/10, 1100 Wien, Austria

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Re: [Tagging] Tagging of topographic areas with a name

2013-08-07 Thread Pieren
On Wed, Aug 7, 2013 at 10:19 PM, Friedrich Volkmann b...@volki.at wrote:
 It should rather be a type=collection relation.

I really hate type=collection. One of the worst idea in OSM. All
relations are collections.

Pieren

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[Tagging] Tagging of topographic areas with a name

2013-08-06 Thread Yuri D'Elia
Hi everyone.

I'm in the alps, and I've been mapping some areas in the region.
I have two questions regarding tagging where I couldn't find a decent
consensus on the wiki.

There are many areas in the region that go by a specific name. I have
two cases where a group of lakes (as a whole) is known by a name, but
then each single lake has also his own lake.

I found an existing example in France, Les 7 Eaux:

http://www.openstreetmap.org/#map=14/45.2466/6.0866

which has been tagged with a multipoligon relation.
Unfortunately, the relation has some problems:

- not rendered anywhere? I would expect that when the scale is high
enough, and there's no place to render the lake names, the name of the
relation is shown. But it's not. On the contrary, unnamed lakes simply
take the name of the relation.

- sometimes I not only have lakes, but I might have other features
inside that area, that are logically part of the same known spot. Is a
relation still a good idea in that case?

It seems to me that the closest tagging scheme might be a loose area
with place=locality. Would that be a good idea?

I did a test, here:

http://www.openstreetmap.org/#map=15/46.4696/10.7590

but again, no renderers seem to pick up this important information (the
name - the boundary itself is not important!), which would be especially
important for a topographic and landscape map.

A related question is the name of the valleys.
I saw several proposed tags in the wiki:

http://wiki.openstreetmap.org/wiki/Relations/Proposed/Region
http://wiki.openstreetmap.org/wiki/Proposed_features/Valley

but not really an official tagging scheme. Valley names are very
important features for a topographic map.

Similarly, we have areas for entire mountain groups, which are
fundamental for a topographic map in the alps. Again, the boundaries of
such areas are not so important, but it's mostly used as an indication
for the name placement.

Thanks!


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Re: [Tagging] Tagging of topographic areas with a name

2013-08-06 Thread Janko Mihelić
2013/8/6 Yuri D'Elia wav...@users.sourceforge.net


 Similarly, we have areas for entire mountain groups, which are
 fundamental for a topographic map in the alps. Again, the boundaries of
 such areas are not so important, but it's mostly used as an indication
 for the name placement.


I don't know about the others, but I've been thinking about this one, and
there's a simple solution. Drawing a big polygon around the whole mountain
is not very effective. There are no clear boundaries for a mountain. But
what we can do is put a tag like mountain=* on all natural=peak nodes.
Maybe even on alpine_huts and other features. That way some software could
find arbitrary boundaries using that data and SRTM data.

Maybe valleys can be solved in the same way.

Janko
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Re: [Tagging] Tagging of topographic areas with a name

2013-08-06 Thread Yuri D'Elia
On 08/06/2013 04:14 PM, Janko Mihelić wrote:
 2013/8/6 Yuri D'Elia wav...@users.sourceforge.net
 Similarly, we have areas for entire mountain groups, which are
 fundamental for a topographic map in the alps. Again, the boundaries of
 such areas are not so important, but it's mostly used as an indication
 for the name placement.

 I don't know about the others, but I've been thinking about this one, and
 there's a simple solution. Drawing a big polygon around the whole mountain
 is not very effective. There are no clear boundaries for a mountain. But
 what we can do is put a tag like mountain=* on all natural=peak nodes.
 Maybe even on alpine_huts and other features. That way some software could
 find arbitrary boundaries using that data and SRTM data.
 
 Maybe valleys can be solved in the same way.

Might still be problematic. A forest, sometime lakes, rivers for sure
and many other big polygons will cross the boundary of the mountain group.

It's kind of unfortunate, because a mountain group will span across
italian regions and include parts of several valleys. Of course,
likewise, valleys have the same problem. It's not a hierarchical
information either.

It's really a topographical information, and I feel like tagging objects
within or using relations might be really problematic. Just imagine what
kind of spotty tagging would you have for big mountain groups. Huts
and peaks would definitely not be enough for a decent boundary.

But also drawing big areas is kind of ugly :(.

Fortunately, the boundaries of the area are not important in themselves.
Nobody renders valley or mountain group borders. But we *do* use such
boundaries for name placement.

I'm thorn.



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Re: [Tagging] Tagging of topographic areas with a name

2013-08-06 Thread Janko Mihelić
2013/8/6 Yuri D'Elia wav...@users.sourceforge.net


 Might still be problematic. A forest, sometime lakes, rivers for sure
 and many other big polygons will cross the boundary of the mountain group.


I wouldn't tag rivers or forests with those tags, just nodes or little
ways. Tagging everything within the mountain with that tag would create
lots of data that could be considered garbage. But if you only tag peaks
and alpine_huts, maybe it could be manageable.



 It's kind of unfortunate, because a mountain group will span across
 italian regions and include parts of several valleys. Of course,
 likewise, valleys have the same problem. It's not a hierarchical
 information either.

 It's really a topographical information, and I feel like tagging objects
 within or using relations might be really problematic. Just imagine what
 kind of spotty tagging would you have for big mountain groups. Huts
 and peaks would definitely not be enough for a decent boundary.


I made this picture, maybe it clears my point:

http://i.imgur.com/CeFG2WO.png

A software would look for the lowest contour line (altitude) that is
between points with different mountain tags. I have a feeling it would
work, but I never tried it. Maybe some problems would arise.



 But also drawing big areas is kind of ugly :(.


Maybe the solution is a separate OSM database, used specifically for these
polygons.

Janko
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Re: [Tagging] Tagging of topographic areas with a name

2013-08-06 Thread fly
On 06.08.2013 16:27, Yuri D'Elia wrote:
 On 08/06/2013 04:14 PM, Janko Mihelić wrote:
 2013/8/6 Yuri D'Elia wav...@users.sourceforge.net
 Similarly, we have areas for entire mountain groups, which are
 fundamental for a topographic map in the alps. Again, the boundaries of
 such areas are not so important, but it's mostly used as an indication
 for the name placement.

Did you have a look the picture of the week [1] a few weeks ago ?

 I don't know about the others, but I've been thinking about this one, and
 there's a simple solution. Drawing a big polygon around the whole mountain
 is not very effective. There are no clear boundaries for a mountain. But
 what we can do is put a tag like mountain=* on all natural=peak nodes.
 Maybe even on alpine_huts and other features. That way some software could
 find arbitrary boundaries using that data and SRTM data.

No this will not work. We need some sort of area and probably more than
one tag, plus a hut might be in a valley, a mountain subsubgroup, a
mountain subgroup and a mountain group and still in an extra region

 Maybe valleys can be solved in the same way.
 
 Might still be problematic. A forest, sometime lakes, rivers for sure
 and many other big polygons will cross the boundary of the mountain group.
 
 It's kind of unfortunate, because a mountain group will span across
 italian regions and include parts of several valleys. Of course,
 likewise, valleys have the same problem. It's not a hierarchical
 information either.
 
 It's really a topographical information, and I feel like tagging objects
 within or using relations might be really problematic. Just imagine what
 kind of spotty tagging would you have for big mountain groups. Huts
 and peaks would definitely not be enough for a decent boundary.
 
 But also drawing big areas is kind of ugly :(.

Still I think it is the only way to go

 Fortunately, the boundaries of the area are not important in themselves.
 Nobody renders valley or mountain group borders. But we *do* use such
 boundaries for name placement.

I think the best would be to invent a new boundary type.

boundary=topologic or geographic
topologic/geographic=valley/cordillera/mountain_range/region

and some ranking for the categories

As the borders are often not that clear and also not that important they
should not be rendered and do not have to be that exact but for
rendering names like in [1] we need them.

My 2 cents
fly

-
[1]
https://wiki.openstreetmap.org/wiki/File:Maxbe-stubaier-beschriftung_en.png

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Re: [Tagging] Tagging of topographic areas with a name

2013-08-06 Thread Yuri D'Elia
On 08/06/2013 04:27 PM, Yuri D'Elia wrote:
 Might still be problematic. A forest, sometime lakes, rivers for sure
 and many other big polygons will cross the boundary of the mountain group.
 
 It's kind of unfortunate, because a mountain group will span across
 italian regions and include parts of several valleys. Of course,
 likewise, valleys have the same problem. It's not a hierarchical
 information either.
 
 It's really a topographical information, and I feel like tagging objects
 within or using relations might be really problematic. Just imagine what
 kind of spotty tagging would you have for big mountain groups. Huts
 and peaks would definitely not be enough for a decent boundary.
 
 But also drawing big areas is kind of ugly :(.
 
 Fortunately, the boundaries of the area are not important in themselves.
 Nobody renders valley or mountain group borders. But we *do* use such
 boundaries for name placement.
 
 I'm thorn.

I'm attaching a crude osm file I edited quickly to demonstrate the problem.

Valleys usually end exactly at the mountain ridges. Valleys also end at
the border of a mountain region or at the border of another valley.
Between valleys, the border is purely arbitrary (it's mostly determined
by geographic properties).

In the alps I would expect a mosaic which is essentially totally filled
with valleys. A relation would be great to re-use existing geometry, but
some new boundary type will also be needed to mark the end where's no
additional geometry can be reused.

I also created two (inexact) mountain groups. Mountain groups actually
form a complimentary mosaic, as you see in the file. A mountain group
would start at the middle of a valley (which I didn't do in the example,
but you get the point) and end at another one. The only exception might
be where you have very large valleys, like the Val D'Adige, where the
group doesn't start in the middle exactly (but doing so wouldn't exactly
be wrong either). For mountain groups I do not see any existing
geometry that could be reused, except occasionally for the nodes where
the valleys cross. A new boundary type is definitely needed, and the
edges could be shared with a mountain group relation.

?xml version='1.0' encoding='UTF-8'?
osm version='0.6' upload='true' generator='JOSM'
  node id='-385' action='modify' visible='true' lat='46.6430679777813' lon='11.052495557349316' /
  node id='-366' action='modify' visible='true' lat='46.49188168894685' lon='11.043871730621769' /
  node id='-347' action='modify' visible='true' lat='46.459302571583' lon='10.36979709656485' /
  node id='-345' action='modify' visible='true' lat='46.348707668264105' lon='10.364026723600112' /
  node id='-343' action='modify' visible='true' lat='46.31049752324693' lon='10.494821428967915' /
  node id='-341' action='modify' visible='true' lat='46.356644089129794' lon='10.727664750611696' /
  node id='-339' action='modify' visible='true' lat='46.42752467234013' lon='10.91235837302667' /
  node id='-337' action='modify' visible='true' lat='46.59815137198975' lon='11.092740082077869' /
  node id='-335' action='modify' visible='true' lat='46.601607818458966' lon='10.867083282707044' /
  node id='-333' action='modify' visible='true' lat='46.61197583489281' lon='10.763597361976476' /
  node id='-332' action='modify' visible='true' lat='46.60802634834044' lon='10.573873173970435' /
  node id='-321' action='modify' visible='true' lat='46.83957020991874' lon='10.644301092245405' /
  node id='-319' action='modify' visible='true' lat='46.805147933633975' lon='10.724790141702512' /
  node id='-317' action='modify' visible='true' lat='46.82088656606407' lon='10.826838757978491' /
  node id='-315' action='modify' visible='true' lat='46.930928039250446' lon='11.023030816030195' /
  node id='-313' action='modify' visible='true' lat='46.8955821746472' lon='11.125798084533468' /
  node id='-311' action='modify' visible='true' lat='46.81252599107442' lon='11.23718917976429' /
  node id='-308' action='modify' visible='true' lat='46.697313033657714' lon='11.088428168714096' /
  node id='-306' action='modify' visible='true' lat='46.67315605116175' lon='11.047464991758245' /
  node id='-304' action='modify' visible='true' lat='46.62678384457391' lon='10.862771369343271' /
  node id='-303' action='modify' visible='true' lat='46.641587804517854' lon='10.611243089789806' /
  node id='-223' action='modify' visible='true' lat='46.39911725379921' lon='10.983395899954589' /
  node id='-221' action='modify' visible='true' lat='46.4202488648184' lon='11.004914609498558' /
  node id='-219' action='modify' visible='true' lat='46.436595031792024' lon='10.971137954815664' /
  node id='-213' action='modify' visible='true' lat='46.644455683599396' lon='11.210808472618753' /
  node id='-211' action='modify' visible='true' lat='46.52888351182877' lon='11.30495191439448' /
  node id='-209' action='modify' visible='true' lat='46.476944108594104' lon='11.358850831441648' /
  node id='-207' action='modify' 

Re: [Tagging] Tagging of topographic areas with a name

2013-08-06 Thread Martin Koppenhoefer
2013/8/6 Yuri D'Elia wav...@users.sourceforge.net

 On 08/06/2013 04:27 PM, Yuri D'Elia wrote:
  It's really a topographical information, and I feel like tagging objects
  within or using relations might be really problematic. Just imagine what
  kind of spotty tagging would you have for big mountain groups. Huts
  and peaks would definitely not be enough for a decent boundary.
 
  But also drawing big areas is kind of ugly :(.
 
  Fortunately, the boundaries of the area are not important in themselves.
  Nobody renders valley or mountain group borders. But we *do* use such
  boundaries for name placement.
 
  I'm thorn.

 I'm attaching a crude osm file I edited quickly to demonstrate the problem.

 Valleys usually end exactly at the mountain ridges. Valleys also end at
 the border of a mountain region or at the border of another valley.



+1, valleys aren't too big usually and should be clearly defined, there is
already a proposal for ridges and it is also used: natural=ridge
http://taginfo.openstreetmap.org/search?q=natural%3Dridge

to define a valley it should be enough to add the adjacent ridges to an
area relation (type=area) and add tags like natural=valley, name=* ...
renderers could in the future connect the ridged to create an (implicit)
area (e.g. to put a text inside).

For other areas other data types might be more adequate:
Some years ago on the German ML there was this interesting idea to define
(fuzzy) areas (e.g. lower scale topographic regions like the European
Alps). You put existing objects (like nodes, ways or relations) into a
relation with the roles inside or outside and some algorithm would
calculate an area that includes all inside and excludes all outside
objects. You won't have to be very precise with this, as this kind of rough
information is only required on lower scales where some kilometers more or
less won't change anything, just a few nodes should suffice to define
something as huge as the Alps, and you could reuse (preferably simple and
stable like peak-nodes) existing geometry.



 In the alps I would expect a mosaic which is essentially totally filled
 with valleys.



+1


  A relation would be great to re-use existing geometry, but
 some new boundary type will also be needed to mark the end where's no
 additional geometry can be reused.



if you need explicit boundaries between 2 valleys (see above the area
relation which doesn't require to explicitly draw these, but allows to do
so if required (role=lateral).



 I also created two (inexact) mountain groups. Mountain groups actually
 form a complimentary mosaic, as you see in the file. A mountain group
 would start at the middle of a valley (which I didn't do in the example,
 but you get the point) and end at another one.



+1, usually you will have a river or stream there, as it is the locally
lowest point (i.e. the needed geometry is already there). An argument
against reusing rivers to define mountain groups is that they often add a
lot of complexity and you'd usually not need the borders of a mountain
group with the precision this allows for (adding relations augments
complexity and raises the barrier for other mappers to edit).

Cheers,
Martin

http://wiki.openstreetmap.org/wiki/Tag:natural%3Dridge
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Re: [Tagging] Tagging of topographic areas with a name

2013-08-06 Thread Yuri D'Elia
On 08/06/2013 07:04 PM, Martin Koppenhoefer wrote:
 For other areas other data types might be more adequate:
 Some years ago on the German ML there was this interesting idea to define
 (fuzzy) areas (e.g. lower scale topographic regions like the European
 Alps). You put existing objects (like nodes, ways or relations) into a
 relation with the roles inside or outside and some algorithm would
 calculate an area that includes all inside and excludes all outside
 objects. You won't have to be very precise with this, as this kind of rough
 information is only required on lower scales where some kilometers more or
 less won't change anything, just a few nodes should suffice to define
 something as huge as the Alps, and you could reuse (preferably simple and
 stable like peak-nodes) existing geometry.

The message from fly, about about boundary=topologic/geographic though
would solve nicely valleys, mountain groups _and_ other topographic
features under a single umbrella, and it's quite easy to achieve.

to fly: Is this some form of official proposal?

Calculating a concave hull from points, especially where you have nested
geometry is very messy process (I used to do it as a gis developer in
the past). I wouldn't really expect decent results even for name
placement.

 +1, usually you will have a river or stream there, as it is the locally
 lowest point (i.e. the needed geometry is already there). An argument
 against reusing rivers to define mountain groups is that they often add a
 lot of complexity and you'd usually not need the borders of a mountain
 group with the precision this allows for (adding relations augments
 complexity and raises the barrier for other mappers to edit).

Ridges can also be quite complex. Also, many times they end way before
the end of the end of the hill or do not exist at all (flat top
mountains). Just to say that the geometry might not always be there.

Also, is there a tagging scheme for the lowest point/depression of a
valley? (I was looking for it recently).



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Re: [Tagging] Tagging of topographic areas with a name

2013-08-06 Thread Martin Koppenhoefer
2013/8/6 Yuri D'Elia wav...@users.sourceforge.net

 Ridges can also be quite complex. Also, many times they end way before
 the end of the end of the hill or do not exist at all (flat top
 mountains).




good point



 Just to say that the geometry might not always be there.

 Also, is there a tagging scheme for the lowest point/depression of a
 valley? (I was looking for it recently).



waterway=river or stream

cheers,
Martin
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