On 04/13/2013 12:52 PM, David Fisher wrote:
Anyway. My two cents, for what it's worth: I am strongly in favour of
mapping highways and railways differently (one way per separated piece
of tarmac for roads; one way per rail for railways). One form of
compromise, however, could be to treat specifically on-highway rail
systems with the "highway" protocol. Or, maybe for multi-rail
on-highway sections, map them as separate ways (cf Addiscombe Road
tramlink) and use a relation just to cover these sections? I realise
this is not ideal for cities with a large proportion of such sections,
but long-term it may be a way to maintain detail whilst limiting
complexity (since relations would not be needed for *every* section,
just shared sections).
This is actually pretty insightful, and lead me to the following thought:
Really my proposal is all about trams. The problems with level crossings
and bridges tricked me into thinking it was a general rail problem, but
really I think the core issue is with these special characteristics of
trams as compared to full-blown trains:
- They have a small form factor like a bus, and unlike a train. This
allows them to behave more like "normal" traffic, with the exception of
not being able to change lanes. For example, they can make tight turns
and can stop quickly when traffic conditions require it. (Trolley buses
are similar in that they are tethered to special infrastructure, but
they have a little more flexibility because of the trolley poles.)
- They usually participate as full members of the roadway... that is,
they often stop at the same traffic signals, the same stop signs, get
stuck in the same traffic queues. On the other hand, when full railways
interact with roads they generally get automatic priority, stopping all
other traffic that might otherwise be using the right of way.
- They often have boarding areas that are more like bus stops than
platforms, and depending on where in the roadway the track runs there
may not be any special boarding facilities at all.
Some of this applies to a lesser extent to light rail in some areas.
So with all of that said, I'm considering reigning in my proposal to
discuss trams only; would one-way-per-tramway but one-way-per-rail-track
be an acceptable compromise? Again I'm really only personally interested
in a comparable amount of detail as trolley_wire=yes, but if it will
help to convince I can again try to create a strawman detailed mapping
proposal.
There is still the problem with level crossings to deal with, but that's
minor and can be dealt with by a separate proposal (tramways don't
usually have level crossings in the same sense as railways anyway) and
otherwise the full detailed mapping of railways is harmless.
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