[talk-au] Edits in and around Mt Barker, SA

bluemm1975-osm at yahoo.com bluemm1975-osm at yahoo.com
Tue Oct 21 05:22:20 BST 2008

Hi Kim,

----- Original Message ----
> From: Kim Hawtin <kim.hawtin at adelaide.edu.au>
> To: Talk-au at openstreetmap.org
> Sent: Tuesday, 21 October, 2008 11:33:25 AM
> Subject: [talk-au] Edits in and around Mt Barker, SA
> Mornen all,
> I've been busy uploading traces and mapping around Mt Barker
> and Littlehampton a bit lately. I have a couple of questions
> I was hoping folks could clear up;
> - Are the rail and road under passes right? I have set them as
>   tunnels, because it makes more sense than the freeway being a
>   bridge, how ever what do other folks use?

Use a tunnel if it is one, or a bridge if that is what is there. I'm sure there are some weird hybrid examples, but if it is a culvit for streams/drains, I use a tunnel. If I'm not sure what is there, I leave it with the ways overlapping without any bridge/tunnel tags (I think the validator in JOSM warns about it), so I or someone else can fix it when visiting it next.

> - I've put in a few round'a'bouts ... they are messy critters.
>   is it the right thing to draw them out with little link roads
>   or should they be put up as where the roads intersect with
>   the joining node and tag that node as a round about?
>   especially larger ones, like the end of Gawler street near the
>   bus interchange?

Bane of my existence!! The OSM wiki says you should only draw the connecting ways as split (which form triangle islands) if it is a large roundabout. A normal suburban roundabout should just be a circle (I use 8 corners) with the 4 ways connected. Merkaartor has a roundabout tool where you click a crossing, select the diameter of the roundabout and it creates a circle with the ways cropped off to it (JOSM might have something similar). Some people mapping Melbourne use mini-roundabout's to save time, but it's only for mini UK style ones with a tiny white painted circle in the middle of the intersection. I'd personally like the junction=roundabout tag to apply to a node, with a eg. junction:width=5m tag, so renderers could draw the circle road & inner island all by themselves without lots of extra effort.

Looking at your B37 & Alexandrina & Flaxley Rd roundabout, you don't need oneway=yes(it's implied), clockwise(just draw it in a clockwise direction), ref(roundabout's don't inherit route numbers, it's for when roundabout's have specific ref numbers [in Europe I think]). The incoming split lanes for B37 should be primary (as it's still the road, not a link, just split into oneway's), as the north ones are, but the south ones are primary_link. Conversely, the East & West split's should be secondary. Split's should have the same tags as the road it splits from, but split's add oneway=yes. Only *_link's and roundabout's don't have ref's or names (except when specifically signposted, UK has examples of this).
The Alexandrina Rd & Fletcher St one is missing the junction=roundabout circle for the roundabout, and missing oneway=yes tags for the split ways.

> - I have been seeing lots of roads and other objects get a blue
>   halo ... there seems to be an attribute against each of these
>   that I didn't mark up, but by my reading, isn't supported by
>   the renderer? especially "ref" and "street" ...

They are "relations" to tie different ways together to form logically-connected ways, eg. routes. They are relatively new to OSM and I haven't played with them much, but others have added them in my area. The only strange thing I can see is that the motorway_link for the B37 & M1 are added to the relations, which I believe is wrong because they are on/offramps, not the actual freeway that the route follows.

> - My edits seem to be taking around two weeks to hit the OSM
>   normal map ... isn't this normally happening weekly?

The main map grabs data on Wednesdays UK time, and then spends a day or two creating new tiles for the map, therefore if you updated OSM on Wednesday our time, it could be a week & a bit before the updates appear. And if you browser (or ISP) has the map tiles cached, you might need to Ctrl+F5 to force a reload from the tile server. Miss match of old & new tiles usually means a caching issue.

> cheers,
> Kim

Tags suggestions
Looking at Mt Barker township, you've done a fantastic job. I noticed a few tagging schemes different to mine:-
* Lots of the area's don't need area=yes, like parking/schools/landuse etc.
* Parking/school doesn't need a separate POI node in the middle, the renderers are now smart enough to stick an icon in the middle.
* Landuse doesn't need to be bounded by streets (cookie cutter'ed), just draw around the outside of the area (landuse is always rendered at the bottom, so no need for layer=-1, which is only used if you can "walk under" something). That should save you tonne's of effort :)
* Similarly, the pitch & parking in the recreation_ground don't need layer=1 (as you can't walk under the parking!!)
* There's streets in the East that are only source=survey, no highway=* tags. If not sure what type of street it is, use the new highway=road tag (basically means, "unknown class").
* I think the highway=traffic_signals on B37 next to Cornerstone College should include crossing=traffic_signals (or just crossing=pelican), as it appears to be a pedestrian crossing, see http://wiki.openstreetmap.org/index.php/Key:crossing.
Also, I'm not sure if you have used the Yahoo layer, but Mt Barker has good coverage down to z17.

It's my personal crusade, but since I don't have a GPS, I've been adding source=yahoo to the ways I've traced (or source=landsat for country regions without high zoom Yahoo imagery). I see a lot of source=survey tags, but the OSM "mavens" on Talk mailing list think survey implies professional surveyed equipment, and prefer source=gps. I see a few source:name=survey tags, which is what I do when I go out for a ride and write down street/POI names in a notepad. Maybe source:name=notepad would be better, but source:name=survey is more popular. Ideally all names have a source:name=photo with a Geotagged photo uploaded to OSM for proof of street signs, but until I get a GPS, there's not much point taking photo's.

Cheers, BlueMM

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