OpenSnowMap.org - blog

I was requested by a few people to use opensnowmap.org tiles on their website.

Now you can find them on:

• Bayern Atlas - Bayern Geoportal
• Labonnepiste.com

To do the same, it's easy: you just have to tell me so, and use a proper referrer and user-agent. Of course you need to acknowledge OpenStreetMap according to this page, and OpenSnowMap.org CC-BY-SA. This is important to tell me before, so that I can check if the server load is ok and warn you about any change.

This only concerns the tiles without hillshading and contour-lines: I'm afraid the load would be to big otherwise.

Of course, if you made any serious revenue thanks to those tiles, maybe you are kind enough to help me and share a part of the Opensnowmap server costs.

It's nice to have the largest ski map worldwide at hand with OpenstreetMap. Now with a few mapping efforts, some really useful services could arise from this data. Not only in putting more pistes on the map (there is still plenty to map !) but also in organizing them by ski resorts with site=piste relations.

Ski resorts pistes, and pistes length

Now on Opensnowmap, you get some usefull statistics on a particular ski resort.

Some resorts seems to be rather well mapped:

While for others ...

There is no ski pistes, just two buildings there.

There is plenty of thing that are not yet mapped in OpenStreetMap. However, I hope these stats will give a good incentive to completely map ski resorts, why not by the operator ?

These stats are obtained by checking the members of site=piste relations.

How-to

A few controls have been recently added to complete the piste list view on Opensnowmap.

To obtain the list view, use one of these buttons to

• list all pistes in the viewport
  

• select a piste by clicking on the map
  

• search a piste by name
  

On the list view, you can:

• List all pistes of a particular ski resort
  

• View the elevation profile of a piste
  

• Get more info about the resort or piste, including a link to OSM browser
  

A few things happened since Christmas. The server had some issues when updating the pistes daily: the (small) disks were full. I took the opportunity to change the server and hosting. All is runnning normally now, and the new server is big enough to handle the relief and contour lines data on the same machine than ski pistes. This means that Opensnowmap now runs with two servers able to serve the same content from two distinct hosting companies. The second one is cheap and slow, but make a descent job as a fallback server.

But that's behind the scene, what's really new ? Here it is :

* Single overlay

The pistes, Modis 8-days snow-cover, hillshading and contour lines are now rendered as a single layer: 3x less tiles to download for a map view. I am sure your browser will like it.

Piste-only layer is still available for third-party websites (be kind enough to ask me before using tiles).

* Search-results - Elevation profile

There is now a feedback on the map when you place the mouse pointer over a piste name in the search-result box.

On the pistes list, a small icon also allows you to get the elevation profile for a single way or single route. This will also show you the route on the map, with an arrow at the beginning to show the followed direction.

Future improvment will be made to improve the interaction between the map and the ski pistes list on the left.

* Sleigh pistes

Long time overdue, sleigh pistes are rendered violet with a sleigh icon. Actually this is not clear if piste:type=sleigh means dogs, horses or camels or whatever, so I choose a sleigh as an icon.

* Czech translation has been updated.

Other languages would benefit from your help, too !

Some Opensnowmap.org services now rely on a smarter pistes search API than previously. It's not replacing a Xapi or Overpass API, but is oriented toward a webservice that allows one to find what people usually calls a 'ski piste'.

On Opensnowmap, there is less redundant search results when searching a piste by its name. It's the same for pistes information and route description when you click on the map. Also, the search function is now a bit tolerant to typos.

A piste API ?

Well, it's a big word for a python CGI making requests to a slightly modified pgsnapshot database.

Simplify search results

What happens if you search for a piste named 'Pauvre Conche' in openstreetmap data? You have 4 alpine pistes results: two easy ways, and two intermediate one. The new API then check if these ways touch each other, and if they share the same tags. If it is the case, they are concatenated. These give only two 'pistes' the blue one and the red one for 'Pauvre conche'.

Also, some pistes are mapped as ways, other as relations. There is even some people that map the pistes as both way and relation, both with the same name. Now the list of result can be filtered to remove the ways if they belong to a relation. This means that the piste 'Le Vourbey' can be found as a single result, omitting the way 'Chemin de coupe le Vourbey' part of the relation 'Le Vourbey'. However, if you use the routing feature of Opensnowmap, then the results will emphasize the way tags, but still show you that the way belong to a relation.

This will hopefully gives a user what he or she is looking for: a ski piste, not ways or relations.

Typos

This is easy: Postgres provides the module pg_trgm that does a pretty decent job.

Performance

Some burden in filtering the results have also been moved from the client (your browser) to the server. Also, geometries are sent as encoded polylines instead of wkt to reduce bandwidth consumption. Nevertheless, some filtering process can be long, so the API restrains itself to process only 50 OSM elements (ways and relations, before filtering) per request to ensure a reasonable response time. So you won't be able to find all the piste named 'Loipe' on Opensnowmap.org website. If needed you can add &limit=false to the query.

C'est parti ! Ma première sortie hier m'a permis d'ajuster La Mathiez Sarrazin, sur le massif de la Haute-Joux. Une premiére boucle assez tranquille que j'ai mappé 'novice', puis une deuxième un peu plus vallonée ou 'easy', le tout avec un bon damage suites aux premières neiges conséquentes. La relation mappée en vert est un peu spéciale avec des passages communs à l'aller et au retour.

Ce domaine qui part de Vaux et va jusqu'à Cerniébaud est vraiment sympa, j'espère bien en compléter le mapping d'ici la fin de cet hiver. Et si quelqu'un complète avant moi, tant mieux !

Opensnowmap.org is now available in a mobile-friendly version.

mobile version

The main navigation features have been integrated in this version.However, you won't find the elevation profile and micro-routing functions. First, because it's complicated, and then, because I did not find any example showing me this could make sense on a mobile screen.

The mobile version benefits from a 'my location' icon that will re-center the map on your location at a few second interval unless deactivated by the same icon. Hopefully, because I figured out that HTML5 geolocation implementation among browser and device seems a bit tricky unless you found the various settings allowing it. So, sorry in advance if you are welcomed by an alert popup: I hope this will help you to find whats wrong.

Technically, the server should redirect you on the proper version based on user-agent. You can then change to the desktop or mobile version from the menu. Your choice will be remembered in a cookie along with your langage preference (including Catalan users, thanks to Joan !).

This has been tested on various Android browsers, but I'm glad to receive feedback fom users on iOS,Windows phone or else.

Yves

The routing function have been improved. Now the start and end points are the closest point on the closest piste. Sound logical, but it wasn't the case before.

This now means that you can take a lift at mid-slope, on Opensnowmap.org website, at least !

For those that did not knew the multi-modal (winter sports only) routing and pistes info capabilities of Opensnowmap.org, click on the the hand icon in the menu bar, zoom down to your favorite resort, and click on the pistes.

Note: Routing on Opensnowmap.org still rely on Pyroute. I had a test recently with Pgrouting 2.0.0 RC1, but did not end up with something worth it yet. I did not gave up yet.

Us and Canadian downhill pistes are now rendered with a local coloring scheme: green / blue / black diamond.

The contour lines database is suspended till further notice for an upgrade (SRTM V4.1 from CGIAR, a bit of smoothing for ASTER data in northem areas).

Les courbes de niveaux seront à nouveau disponibles après une mise à jour (SRTM V4.1 grâce à CGIAR, les données ASTER seront également adoucies pour les régions nordiques).

Yves

First of all, thanks a lot to all bugs / feature request reporters !

The map:

• Downhill pistes are now renderd as area (area=yes) see
• Names on downhill pistes
• Resorts are now renderd from zoom 8 see
• The lifts icons are now the head up see
• Fix sled and skating icons placement

Website:

• Move blog to new address blog.opensnowmap.org
• Refresh interactive mode button design
• Lot of translation fixes
• Remove forum. It's been hacked :(

Data:

• Move Osmand off-line (vector) map generation to the new server
• Update Osmand-ski