[OSM-talk] colour fills in osmarender

[Richard Fairhurst]

Tom wrote:

> In terms of UI, I think this is the way to go right now.  If people
> want to make a way containing only one segment, that shouldn't be a
> problem.  The interface should be geared to
> create/merge/manipulate/annotate ways, not segments.  I'd be
> interested to hear from Richard what his focus will be for his
> proposed Flash editor - will it work this way?

Yes, absolutely.

The Flash editor has just one drawing tool, for ways. You can't draw  
segments which aren't part of a way. Joe Punter won't actually need to  
know what a segment is. (For old segment support there'll eventually  
be an option to "convert these segments to a way", but it's not part  
of the core UI.)

>> How would a roundabout be defined?
>
> I would have thought that depends on whether the roundabout has a name
> or not, and precisely how the streets cross it.  Mostly, I would have
> thought that the loop itself would be a way, unless there is a clear
> cut case where one road obviously runs continuously over a roundabout,
> in which case the way-ness of that road should take priority and the
> roundabout should fill in the gaps with as many ways as are needed.

Yes, agreed. So roundabouts could be:

- defined as individual ways
- multiple 'ref' tags, one for each road that meets at the roundabout  
(e.g. ref=A361,ref=A44,ref=A3400 - this avoids the need to say "turn  
onto the A361" then "turn back onto the A44", because you simply  
prefer the ref you're already on)
- junction=roundabout
- oneway=clockwise|anticlockwise

> This will vary from roundabout to roundabout, someone might care to
> catalogue the potential configurations and find examples of each, but
> that someone probably isn't me (on email... I'd be happy to sketch it
> on a beer mat, such are my inclinations).

Ok. Elevated interchanges are no problem, they can just be dealt with  
by oneway sliproads and the like.

The most complicated, commonly-found same-level one I can think of is  
the donut (fixed-width character set required):

     _|_
___/___\___   (all on one level)
    \___/
      |

where there's a non-elevated route through the middle of the  
roundabout, controlled by traffic lights. (For any Oxford people, this  
is the sort they're putting in at the Headington Roundabout.)

Now, I don't actually see any reason why this can't be mappable by  
including the bit through the middle (the "jam"? - hmmm, sounds more  
and more like Headington) just as a normal way, without special  
roundabout tagging.

> Any serious roundabout should not be a point.  Mini roundabouts that
> people routinely drive across should probably be a point.

That's good, I was getting a bit frightened about how we were going to  
map the Magic Roundabout in Swindon.

(In general, FWIW, my personal preference would be to simplify the  
data model by eliminating segments... but I'm not really that bothered.)

cheers
Richard