Байкал больше не coastline

Так вернуть coastline, или байкал без него оставить? :slight_smile:
Добавить его заново дело 5 минут.

Я за возвращение.

Ну автору правки-то напишите сначала. Может быть он прав.

Он не прав хотя бы потому, что совершил масштабные изменения не посоветовавшись с локальным сообществом.

http://www.openstreetmap.org/browse/changeset/14784583 завтра снова(точнее у меня уже сегодня( придётся восстанавливать coastline на Рыбинском.

Написал, пригласил сюда.

Hello everybody. I am sorry I am only able to write in english (or german if your prefer. :slight_smile: )
Since Ivan Komarov asked me to discuss some of my edits here I think he won’t mind me quoting his message:

Sorry if my edits raised concerns. I do all of them to my best knowledge.

As I wrote on my verbose changeset comments like here I did enhance or add objects from aerial imagery, (I also didn’t see the sense of multiple multipolygones containing one polygon) and - what obviously raised your concerns - removed what is in my opinion redundant tagging. I don’t think it is neither needed nor wanted to have both a multipolygon of the waterbody and its islands plus natural=coastline on all the features. So I removed the one which imho is more likely to fail/more difficult to fix.
For example this island of Lake Baikal doesn’t show up since the coastline shapefile was last updated October 13th and (afaik) since then fails to build without error to have another go at updating it.

I hope I answered your questions.

Feel free to do what you think you have to do.

PS: Maybe it is of interest I created in 2009 Lake Nasser with ~8140 km shore, did not use the coastline tag on it and afaik it never had problems to show up.

malenki, thanks a lot for presenting your position! I am translating your answer to others:
Привожу перевод.

Я за то, чтобы осталось что-то одно - или coastline или natural=water.

Я за coastline для всех озёр площадью от пяти тысяч км²: Каспия, Байкала, Ладоги и Онеги, а также приграничных озёр от тысячи км², вроде Чудско-Псковского или Ханка. Разумеется, coastline и water взаимоисключающи.

В принципе, не имею ничего против того, чтобы сделать костлайнами все озёра от тысячи квадратных километров (список, их 10 штук).

А может кто-то внятно объяснить зачем нам нужен coastline на внутренних водах?

(Could someone explain why we need coastline on internal water areas?)

Затем же зачем вообще был придуман coastline - оптимизация алгоритмов. Гигантсткие мультиполигоны ворочаются слишком медленно.

Some summary,

According to Sergey Astakhov natural=coastline is needed to process large objects during export to different map formats, while huge multipolygons requires a lot of time to process.

Multipolygons itself needed to keep grouping of OSM objects.

Zverik requests to keep natural=coastline for all internal waters larger than 5000 km2 (4 for Russia: Caspian Sea, Baikal, Ladoga and Onega) or even for all larger than 1000 km2 (10 for Russia).

As far as we see, there is no defined edge in OSM wiki or else for setting natural=coastline other from “The Great lakes, and other very large bodies of freshwater, are treated as being sea even though they are actually freshwater, and tagged as coastline.”

So, our community mostly for returning of natural=coastline.

Some summary,

Tagging stuff for the purpose of faster export sounds to me like tagging for the renderer/exporter.

You can also put the names, Wikipedia-Links and stuff directly to the shore tagged with coastline. After all meanwhile we have tools to map work easily on such big objects (e.g. JOSM and Overpass API).
For my understanding this also could be related to Relations are not Categories

As I said I don’t mind either using coastline or MPs with the tags needed. I am not the only one considering using both for the same objects as wrong. Additionally you have twice the work at fixing/maintaining

As said:

Who am I to tell people how to map stuff.

PS;for the record: for the Rybinsk Reservoir (my latest edit regarding coastlines): it exists since 2011.03.29. The first time coastlines were added was in 2013.01.14

I agree with this. In the era of high performance computers things should be made easy for humans to edit not for computers to process.

//Tagging stuff for the purpose of faster export sounds to me like tagging for the renderer/exporter.
Tagging is for at least someone can use the Map. Not just for fun, in write-only mode.

And in Russia there are a lot of users of osm-exports.

Когда мы увидим на 5 зуме Рыбинское вдхр?

This could be of interest to this topic, too: state of the osm coastline

это не в этой теме конечно, но я как-то пробовал, но возникли проблемы с выгрузками для навигаторов.

The 2016 Google maps have a more realistic shoreline for the north Caspian. OSM still shows a very old and outdated shoreline. I have begun adding dirt roads used by our offroad cycling group here in Atyrau KZ. We are also adding canals constructed at several locations in what OSM would call Caspian. There are conflicts with having a dirt road and canal that is inside the boundary of the Caspian.

Is there any way to reconcile the actual shoreline between OSM (very outdated) and the 2016 Google?

Cheers,

cactolith