OpenStreetMap

pnorman has commented on the following diary entries

Post When Comment
OpenStreetMap Carto Complexity about 2 years ago

In addition to Mapbox Streets there are also other styles that use preprocessing. Like OpenTopoMap

I hadn't counted those lines, but there's only about 50 there. And of those, only about 10 lines seem to be ones you should run, the rest are a SQL statement that doesn't seem to do anything.

CartoDB basemaps also use some preprocessing, but not trigger-based like Mapbox streets.

3k lines of preprocessing triggers and other SQL is, in my experience, unique.

In fact you could say through the coastlines all styles make some use of external data preprocessing that is based on additional code

None of them are maintaining their own coastline code, except perhaps to import coastlines into PostgreSQL. I think I counted it where they're doing that but shouldn't have, because I didn't count osm-carto get-shapfiles.sh which is also probably longer than other styles.

Quite a lot of the code complexity in osm-carto is there to work around limitations of the capabilities of the software used

All the styles use PostgreSQL, PostGIS, and Mapnik. I don't think any of them are making any assumptions about versions, unless they happen to create databases and use the CREATE EXTENSION syntax. I guess some of the CartoCSS styles would also work with Mapserver and magnacarto instead of Mapnik and carto, but no one is targeting that.

many styles use external non-osm data which often essentially means externalizing processing complexity

With the possible exception of CartoDB, they're not editing the external sources. If they don't have to edit them, it doesn't add to the maintenance burden.

Quantifying HOT participation inequality: it's complicated. about 2 years ago

I think referring to the workload spread as "unfair" is misleading. "Inequality", although probably correct from a statistics point of view, is also a word that is associated with discrimination.

I'm not surprised to see power-law distributions. When I looked at overall contributor stats, changeset size, API reply size and several other measures, I saw power laws coming up.

Use Grass&Green and enhance the data classification over 2 years ago

So, it's basically an editor that just shows you only features with some natural and similar tags?

It's interesting to call forest grass-covered, since neither natural=wood or landuse=forest implies the presence of grass.

Improving the OSM Map - why don't we? [11] over 2 years ago

Neighborhood has a formal administrative meaning.

The place tags are for geographic places, not administrative divisions. Sometimes these are the same, sometimes not. For example, a town nearby, Langley, is composed of part of the City of Langley and Township of Langley, which are both administratively cities. A mistake that sometimes happens in the US is to call any incorporated area a place=city.

If we wanted to avoid using British English in tags, we could encode all tags as arbitrary numbers or strings. Except, to someone not working in English, that's already what we do, because they should see a translation for the presets.

Harry Wood admin abuse. Do we need him as admin at wiki??? over 2 years ago

I truly believe that my edits were slowly improving content and they are supported

With repeated requests to permanently ban you after your 3 month ban expired, this is clearly not the view of many others.

Postigs question - find out the unnecessary points that exist on the map over 2 years ago

Doing a way simplification with a threshold of 0 is unlikely yield any practical speed improvements.

It takes about one to two days to import the planet with osm2pgsql, assuming reasonable hardware. The node parsing stage takes about 15 minutes. It's unlikely to speed up multipolygon-related computations, the slowest part of the import. It won't speed up clustering or rendering table index creation.

My guess is that there would be no detectable speed increase.

How many days or weeks does it take to upload the whole planet via Osmosis ? over 2 years ago

What area did you use for testing your command, and how long did it take?

Did you load in either the linestring or bbox columns?

What speed drives do you have?

exit_to vs destination (USA) over 2 years ago

What would be interesting is counts of exit_to without destination and destination without exit_to.

But harder to query.

What do maps mean to us? over 2 years ago

To see what people would map themselves, we can look at how mapping has progressed in OSM, and how mapping progresses as a new area puts itself on the map without distortions from imports or organized non-local mapping.

From this, we can see residential areas (landuse=residential) and comprehensive building coverage are some of the lowest priorities, but these are regularly the main focus of humanitarian mapping.

New road style for the Default map style - highway=path is evil over 2 years ago

There is one sensible way of dealing with highway=path, and that's to use Lua processing (available in osm2pgsql as well as other tools such as OSRM and tilemaker)

I wouldn't rule out dealing with it in SQL. It might even be sane, compared to doing z_order in SQL and some of the other constructs.

Osm2pgsql 0.87.4 release over 2 years ago

Just to note, this message was a couple weeks late in getting up.

San Francisco data imports, anyone? over 2 years ago

City and County would like to leverage OSM excellence, yet OSM licensing restrictions make it not feasible for us to use these OSM shapes as our own public reference set

Just to clarify, it is city and county licensing policy and would likely impact any foreseeable license.

New road style for the Default map style - the first version over 2 years ago

Is switching from blue motorways necessary? I realize that blue doesn't cleanly fit into a yellow orange red scheme, but it's unfortunate to lose a color which currently doesn't conflict.

It might be worth looking at http://colorbrewer2.org/?type=sequential&scheme=YlOrRd&n=5 and other options, though blue fits more naturally at the end of a YlOrBr scheme.

San Francisco data imports, anyone? over 2 years ago

California needs a lot of import attention. But the attention it needs is not more imports, it's cleanup of existing imports, particularly landuse imports.

Post scriptum to "long time - no edit" over 2 years ago

Having looked at other projects, our conversion and retention rates are reasonable. That doesn't mean we shouldn't strive to improve it, after all, many of the accounts belong to people who have shown some interest in OSM, but it's a fact of life that people sign up for online accounts then disappear.

Is it the moment for OpenStreetMap? over 2 years ago

Mateusz, it is now. With the new CT, everyone agrees to further relicensing without individual agreements.

Yes - and no. It depends on the license. In the case of a switch to public domain, I estimated at one point that >20% of data would need to be removed - basically most non-US imports. There are additional complications with PD, but they're not worth going into since the chances of a license change removing ~10x the data that was removed in the original license change are approximately zero.

In the case of a switch to an attribution license or different share-alike license, it depends what license. There are many attribution licenses used by third-party sources, and I expect some of them are incompatible with licenses we might consider moving to.

Thirdly, third-party ODbL-licensed data can be imported or used as an external source. This data would need to be removed with any change to the license.

What the CTs mean is that everyone has agreed to a license change process for their contributions.

Nepal, OSM License, and the NGA over 2 years ago

if they're modifying OSM data, rendering in into a produced work (e.g. a map) and publicly distributing produced work they have to make the modified database available*. Looking at the NGA atlases they appear to be layering OSM data with other data, not modifying OSM data. There are some minor attribution problems where they've mangled the OpenStreetMap name slightly and haven't provided license information or a link to it.

The same is probably the case with the Sochi maps, but I'm less sure without comparing geometries.

Using ODbL data within a company or government and not releasing anything publicly is allowed by the license. The share-alike obligations only come into play if something is released publicly.

  • Or other similar options under ODbL 4.6
_ almost 3 years ago

Any update on the source for the initial edit from Andgol? It obviously wasn't the link given, since that spells it differently.

February release delayed almost 3 years ago

It would also help if you were a user of Oracle's list of Root Certificate Authorities if you ask them when they intend to join and use the CA/Browser forum - the industry association for CAs and users, or use the Mozilla ca-certificates component, used by multiple vendors.

Japan, why are you so beautiful? almost 3 years ago

When did you ship Eric off to North Korea? ;)

enf