[OSM-talk] Turn restrictions ambiguity

[marcus.wolschon at googlemail.com]

On Thu, 23 Apr 2009 23:49:54 +0100, Matt Amos <zerebubuth at gmail.com> wrote:
> On Thu, Apr 23, 2009 at 9:16 PM, David Earl <david at frankieandshadow.com>
> wrote:
>> If one were to refer to nodes on the two ways instead of the way itself,
>> it would remove the ambiguity wouldn't it? Albeit more complicated for
>> the consumer to work out, in that it would have to decide which way the
>> two nodes were on.
> 
> an alternative is to use the implicit direction of each way where
> there is ambiguity, as is done for oneway. this would mean all
> combinations can be uniquely resolved without way splitting or
> explicit reference to nodes. it is also forward-compatible with the
> existing scheme.

So something like
type="restriction"
restriction="no_left_turn"
X in role="from_reverse"
Y in role="to_forward"
Z1 in role="via"
Z2 in role="via"
Z3 in role="via"

?
Does not look more user-friendly to me then.

type="restriction"
restriction="no_left_turn"
X in role="from"
Y in role="to"
Z1 in role="via"
Z2 in role="via"
Z3 in role="via"


> it would seem that the most user-friendly way of presenting this would
> be built-in editor support*, e.g: by drawing an arrow from one way to
> the other showing the disallowed route, rather than expecting users to
> "parse" the relation themselves.

Well, sure.
But as with all the other people asking for special support in editors,
routers,
renderers, ... for any features besides basic editing... You have the
source.
Feel free to write it.


Marcus