[Tagging] Race track

[Anthony]

On Sun, Jan 31, 2010 at 11:15 AM, John Smith <deltafoxtrot256 at gmail.com>wrote:

> On 1 February 2010 02:10, Anthony <osm at inbox.org> wrote:
> > Maybe your implementation of micro mapping lanes doesn't have anything to
> do
> > with areas, but then, if so it probably doesn't work.  How do you
> represent
> > gore areas which have highly variable widths as anything but areas?  If
> > you've got a solution for it I'm all ears.
>
> Think railway tracks...
>

I think railway tracks have constant widths.  Otherwise the trains would
have a lot of problems.


> Why do you need to represent road way area so accurately to show the
> lane to be in to exit as depicted, I highly doubt that depiction used
> area information to display the lanes etc, it would have been
> estimations.
>

I don't understand the question.

> Areas are also by far the easiest way to indicate both widths and
> > connectivity.  In order to map
>
> Areas are of limited value besides showing where the road base
> occupies, and even then it won't be 100% accurate since we're not
> doing raster mapping.
>

Why is raster mapping more accurate?  I thought the point of vector graphics
was that they were *more* accurate.  Nothing is going to be 100% accurate,
of course.

Limited value besides...  Fine, at least you agree it is of some value.


> As for connectivity, highly doubtful, you can't indicate valid
> direction that traffic can go.
>

You can if you designate one way as left and one way as right.  I do not
mean for "area" to imply "single closed way".


> >
> http://mytechnews.info/b/wp-content/uploads/2009/02/nuvi-lane-assistance.jpg
> > you need to represent the two lanes on the right and the three on the
> left
> > as separate ways.  But you also need to show that it is possible to route
> > between them (although with extra caution - i.e. a solid white line).
>
> Again, think railway tracks... how do railway tracks merge and split?
>

Not like roadways.  Trains can only drive along tracks.  Those tracks are a
fixed distance apart.  It's nothing like a highway.

> but if you want to avoid a lot of complicated work you have to map the
> > *sides* of the (sets of) lanes, not the *middle* of them.
>
> Or using some kind of cascade method from ways so you can use the
> existing way tags to flow down into lanes...
>

I'll stick with the specific solution I've already worked out, rather than
"some kind of cascade method".
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