[talk-au] secondary_link

[Darrin Smith]

On Mon, 10 Mar 2008 15:07:02 +1030
Jack Burton <jack at saosce.com.au> wrote:

> > I've found roads of secondary, tertiary and residential categories
> > that effectively have _link level turn lanes in addition to central
> > turning lanes. In the case of tertiary and residential I've just
> > using the normal tags for all of them (and having to put the name
> > of the road in on every case to shut up the validator & map lint)
> > although I might have snuck a tertiary_link or two in around the
> > place to be honest :)
> 
> Hmm, good point. I don't think just adding secondary_links into the
> dataset alone will solve the problem though.

I didn't do it completely off the top of my head, I did think "I wonder
if secondary_link and tertiary_link will work?" so I threw in a couple
of them, waited for information freeway to update, saw secondary_link
DID work and tertiary_link didn't so I just assumed someone hadn't
updated Map Features and it was a workable option. As for the using
them in the wrong place well that's been made clearer to me now and
I've cleaned up nearly all those issues near me now anyway.

> Having thought about it a bit now, I think secondary_link and probably
> tertiary_link as well should be made valid values for the highway tag.
> But we should probably introduce this as a proposed feature on the
> wiki for a while before actually using them, hopefully getting at
> least the main renderers to recognise them first.

Guess the validity of this depends on exactly how those roads are
defined. Which is of course issue of that other thread ;)

> I'm not sold on _link derivatives for highway=residential or
> highway=unclassified though. If these have central turning lanes, they
> should probably be upgraded to highway=tertiary anyway. 

I never suggested these and there's a number of roads where it's
unreasonable to make them any higher (there's a number of them around
the Elizabeth area for example, big wide roads that go nowhere).
But if we eliminate the issue of me getting those crossovers done it
largely goes away anyway :)

> Where
> residential roads have slip lanes, they often have addresses on them
> (cf. slip lanes on more major roads), so would need to verify which
> street at the junction those addresses belong to (quick look at street
> numbers for continuity should do the trick), then name the slip lane
> accordingly.
> 
> As an alternative for use with highway=unclassified &
> highway=residential, would tagging the slip lanes and/or central
> turning lanes as highway=service be suitable?

Ah now you are talking about 'turn left anytime with care' type lanes
where the "_link" option kind of fits, my thoughts were once I realised
anything < secondary wouldn't work with _link and given they're
generally pretty rare just label them as the existing road type with
name.

-- 

=b