huge gaps in z12, visually missing streets

[dieterdreist]

Expected behavior

consistent map browsing experience

Actual behavior

misleading voids because of missing minor roads in z12

Links and screenshots illustrating the problem

https://www.openstreetmap.org/#map=12/41.8970/12.4837

[matkoniecz]

Can you mark areas where this is a problem?

[matthijsmelissen]

I don't think these voids are misleading, as these are areas where you cannot get by car. I think car navigation is more important than showing the city structure at that zoom level.

[dieterdreist]

sent from a phone

On 25. Oct 2018, at 22:56, Matthijs Melissen notifications@github.com wrote:

I don't think these voids are misleading, as these are areas where you cannot get by car. I think car navigation is more important than showing the city structure at that zoom level

then it should look again very different and you should render specific restrictions, you cannot go on the visible roads nearby either, unless you are a resident or otherwise authorized (limited traffic zone). The whole center is restricted.

https://romamobilita.it/it/servizi/ztl/ztl-centro-storico

[matkoniecz]

@dieterdreist Can you mark areas where this is a problem? I am unsure what parts of rendering are problematic (I can guess but I prefer to be sure before spending time describing my reasoning for this particular rendering decisions).

[dieterdreist]

Here you go:

[Adamant36]

I hate that. Northern California has the same problem at Z7.

[matkoniecz]

I hate that. Northern California has the same problem at Z7.

Can you give an example of affected location?

[matkoniecz]

In case of z12 I made assumed that

• landuse=residential is passable for pedestrians
• landuse=residential is passable for local vehicle traffic

I also wanted to avoid problem of showing too much data that is not only not giving more information but rather obscures it - see https://www.openstreetmap.org/user/Mateusz%20Konieczny/diary/34957 for this problem in the old map style.

At the same time I considered desirable to show major roads.

So in the end I decided to rely on landuse tagging at z12 to show that area is passable for local traffic and pedestrians and do not show minor roads there. It is possible to show minor roads at this zoom level but it makes impossible to distinguish structure of roads of a higher range.

Note that areas you marked are exactly areas without landuse tagging.

Note that I considered "landuse is no longer completely obscured by roads at z12 and similar" as not a problem.

Also, showing minor roads at z12 would make impossible to keep them from forming blob where individual roads are not distinguishable in cities, even for people with perfect monitors and without any eyesight problems.

---

To summarize: it works as expected, with tradeoffs as expected - road network is visible in cities, missing landuse is visible and leads to worse rendering (what, given that one of this map style goals is to give feedback to mappers I considered as acceptable and maybe even desirable).

So: it works like expected but different priorities would lead to different rendering, after mapping missing landuse problem will disappear.

[dieterdreist]

Am Fr., 26. Okt. 2018 um 10:48 Uhr schrieb Mateusz Konieczny < notifications@github.com>:

In case of z12 I made assumed that

• landuse=residential is passable for pedestrians
• landuse=residential is passable for local vehicle traffic

IMHO landuse does not have implications on accessibility by foot or vehicle, at least not "residential" landuse and as it is often used (including roads). If it were only used in a detailed mapping way, landuse=residential/commercial/retail/industrial etc. would not contain public roads and residential landuse could probably be seen as likely accessible only to residents (in most cases), although there are also "semi-public" areas in many urban contexts, where ownership is private but accessibility is permissive.

What bothers me with current z12 rendering is that it hides pedestrian roads, which are roads just as are residential roads, with the exception that general vehicle traffic is excluded. Not showing them here misrepresents the urban structure.

The other problem is the absence of buildings, which at this zoom level are already essential in many areas to better understand the space.

[matkoniecz]

IMHO landuse does not have implications on accessibility by foot or vehicle, at least not "residential" landuse and as it is often used

I fully agree. But I assume that areas of landuse=residential/commercial/retail large enough to be noticeable at z12 are passable for local residents.

What bothers me with current z12 rendering is that it hides pedestrian roads

I am pretty sure that it was already reported and discussed.

The other problem is the absence of buildings, which at this zoom level are already essential in many areas to better understand the space.

buildings at this zoom level are noise and useful only in cases where landuse is not mapped

[mboeringa]

The other problem is the absence of buildings, which at this zoom level are already essential in many areas to better understand the space.

buildings at this zoom level are noise and useful only in cases where landuse is not mapped

I have to agree with @matkoniecz here, Z12 is something like a 1:100k-1:200k scale map. Showing individual buildings at that scale is nearly impossible, and will certainly not add a lot besides ultra dense clutter. Almost all official topographic maps start showing individual buildings only from scale 1:50k downwards, and even at that 1:50k scale, usually in generalized form for dense urban areas like a city center. Only 1:25k scale maps generally show mostly individual buildings or building blocks (city centers).

Buildings at Z12 is stretching it...

[kocio-pl]

I also think that z12 should not show every possible street type - it's enough to know what type of area is here to not make a high frequency noise, just to see a road backbone.

[matthijsmelissen]

As there seems to be no support for this proposal, I'm going to close this issue.

[dieterdreist]

sent from a phone

On 26. Oct 2018, at 17:20, Matthijs Melissen notifications@github.com wrote:

As there seems to be no support for this proposal

there was no clear proposal, there was a clear description of a problem: densely used and mapped places which looked fine for years and only recently appear “empty” which is a misrepresentation for the center of Rome.

[kocio-pl]

Lack of residential (or maybe some other?) landuse there is disturbing to me, not lack of individual small roads.

[dieterdreist]

not sure it is residential landuse,

there are other places with similar problems in the centers, e.g. https://www.openstreetmap.org/#map=12/31.6287/-7.9889

On 26. Oct 2018, at 23:27, kocio-pl notifications@github.com wrote:

Lack of residential (or maybe some other?) landuse there is disturbing to me, not lack of individual small roads.

— You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub, or mute the thread.

[jeisenbe]

At z12 all developed or urban languages are rendered the same (#d0d0d0), so retail/commercial/residential/industrial and now social amenities will all look like one urban area at z12 (and z11).

I imagine central Rome would have a mix of these urban land uses.

[matkoniecz]

there are other places with similar problems in the centers, e.g. https://www.openstreetmap.org/#map=12/31.6287/-7.9889

Can you mark problematic areas that are not missing landuse?

In Marrakesh I see one empty area - and it is large train station without mapped paths and roads through it so it shows it correctly as a gap.

[dieterdreist]

sent from a phone

On 27. Oct 2018, at 11:07, Mateusz Konieczny notifications@github.com wrote:

Can you mark problematic areas that are not missing landuse?

I don’t know about missing landuses, you seem to imply that every area of land should get a landuse in osm, but I don’t see the values for this. Tourism=museum already implies a museum landuse, for hospitals there is no landuse, nor is there for archaeological areas, parks, universities and schools, airports or for police stations and fire departments. For government buildings there is still discussion on the mailing lists. Can you explain where the absence of landuse=* tags means there are landuses missing?

[matkoniecz]

All areas marked in https://github.com/gravitystorm/openstreetmap-carto/issues/3479#issuecomment-433321407 are generally without landuse=residential or any other standard landuse=* and generally not covered by areas like tourism=museum or areas like hospital, park, university, school or others that you mentioned.

There may be small areas of landuse=* or other mentioned above but they cover less than 10% of this area.

[dieterdreist]

sent from a phone

On 28. Oct 2018, at 06:32, Mateusz Konieczny notifications@github.com wrote:

All areas marked in #3479 (comment) are generally without landuse=residential or any other standard landuse=* and generally not covered by areas like tourism=museum or areas like hospital, park, university, school or others that you mentioned.

not true, you should have checked this before making such a statement, it’s the opposite: they all have significant parts of museums, hospitals, historic sites, squares, universities and libraries.

Apart from this, landuse=residential is not appropriate in general for the Roman city centre, and other mappers have seen it the same until now.

[dieterdreist]

sent from a phone

On 28. Oct 2018, at 06:33, Mateusz Konieczny notifications@github.com wrote:

There may be small areas of landuse=* or other mentioned above but they cover less than 10% of this area.

there are 3 areas marked, of which 2 are entirely consisting of the mentioned features. For centres there is generally no appropriate landuse in OSM.

[matkoniecz]

I checked https://www.openstreetmap.org/#map=17/41.92762/12.46538 with https://overpass-turbo.eu/s/Dak

From what I see 10% is an underestimate but 100% is also an overestimate.

amenity=*, tourism=* areas are not rendered as built-up on z12, and it probably should be changed. This area, once mapped may be an useful test case (though it may be better to open a new issue for this specific problem as this one is mix of multiple problems, tradeoffs and different preferences).

[dieterdreist]

sent from a phone

On 28. Oct 2018, at 08:41, Mateusz Konieczny notifications@github.com wrote:

From what I see 10% is an underestimate but 100% is also an overestimate.

I see gaping holes in the center and believe it is a misrepresentation. Not showing military landuse any more at z12 also contributes to this effect.

[matkoniecz]

Only small military area are hidden at z12.

Showing them as built up areas would not work as many are rural or wild areas.

I see gaping holes in the center and believe it is a misrepresentation.

About 20% of area is mapped with tourism, leisure, amenity areas and not mapped with landuse areas (though I suspect that landuse=commercial may be suitable).

None of that is rendered as built up area on z12 leading to complete gap.

One large area fully covered by amenity/tourism/leisure areas, not covered by landuse is found my plan is to.

(1) ask tagging community whatever they sure sure that no landuse value is applicable, including landuse=commercial

(2) in case of confirmation - add rendering of built up area on z12 and similar for this areas

[dieterdreist]

sent from a phone

On 28. Oct 2018, at 10:59, Mateusz Konieczny notifications@github.com wrote:

About 20% of area is mapped with tourism, leisure, amenity areas and not mapped with landuse areas (though I suspect that landuse=commercial may be suitable).

it is a mix of commercial, retail, tourism/culture, residential and administrative that is typical for city centers, plus a lot of archaeological sites. Are theatres commercial landuse? Museums? Restaurants? Hotels?

[matkoniecz]

I think that most of them fit, due to significant implications I probably should confirm it on tagging mailing list.

[matkoniecz]

I posted message on tagging mailing list about ones that seem to be obviously landuse=commercial.

Cultural ones like archaeological sites and museums or theatres are a bit trickier and I will keep them for the next thread.

[jeisenbe]

Restaurants are retail, hotels are usually commercial, but they can be retail if the ground level has a restaurant and shop.

[matkoniecz]

@jeisenbe @others

Please, reply on a tagging mailing list.