Proposed features/specifying changes in laneconfiguration

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specifying changes in laneconfiguration
Status: Abandoned (inactive)
Proposed by: *
Tagging: [[Key:lane.<lanelabel>. connectsto|lane.<lanelabel>. connectsto]]=[[Tag:lane.<lanelabel>. connectsto=<way-id>.<lanelabel>|<way-id>.<lanelabel>]]
Rendered as: laneconfiguration should be shown


This feature is for specifying changes in laneconfiguration: 2,3, .. roads come together and the total number of lanes is reduced, a road changes from 3 lanes to 2 lanes, ...

Some questions:

  • What if a way that is referenced/connected to is deleted? This should be prohibited or the connection should be highlighted as broken or ... Can it be that a new way with the same way-id is created in the same place? So, the mapping should be deleted when the connectsto-way/lane(s) is deleted. Or, the deletion should be remembered and a warning should be given, if a new way with the same way-id and lanelabels is created again at the same place.

So, first be sure that have labelled all lanes that will NOT dissappear. A lane, that is not labelled will dissapear at the end of the way.

Next, create your "connectsto"-mappings. A lane that has no "connectsto"-mapping will dissappear also at the end of the way.

Add "lane.<lanelabel>.connectsto tags" for the lanes of the way for which configuration will change. Add the right values to the tag-keys. This means that for each tag, you have to specify the way-id and the lanelabel for the lane that the lane, that you're tagging, connects to. You may only specify way-id's and lanelabels that directly connect to the way-id and lane, that you're tagging/connecting from. In other words, the lanes have to be directly connected. All the specified labels have to exist!

If the way-id that is connected to (the value) contains lanes that aren't connected to from somewhere, then these are new lanes that start to exist from this point on. New lanes don't have to be only created on the sides of the road, the may also be started somewhere between the outerlanes!

A "connectsto"-tag can also contain multiple way-id/lane-items. The different way-id/lane-items are separated by commas. The different way-id/lane-couples have to be physically adjacent to eachother. This means that the lanes are shrinking on the innerside and the outerside to the number of lanes specified. This is not the same as the above case where lanes disappear! The difference is the way in which the lanes are merged. The shrinking happens on both sides of the adjacent lanes. For example:

     lane.lane1.connectsto = 45678987.lane1
     lane.lane2.connectsto = 45678987.lane1

Multiple lanes of the same road may specify the same way-id/lane-couple. This means that the road is enlarged on the innerside and the outerside to the (number of) lanes that is mentionned. The lanes that are connected from and those that are connected to, have to be physically adjacent. The connected from-lanes may not have multiple connected to-lanes in this case!

So, for example. A 3-lane-road that shrinks to 2 lanes. More specifically, one innerside-lane is deleted: (Remember: The lanes of a road are labelled from the outerside to the innerside of the road.)

tagging from-way: 
  lanes=lane1,lane2 
  lane.lane1.connectsto = 45678986.lane1
  lane.lane2.connectsto = 45678986.lane2
tagging to-way (way with way-id 45678986):
  lanes=lane1,lane2


I don't see the point in this. Why not just split a way in two and tag one half with "lanes=3" and the other half with "lanes=2". Even drivers on the outermost lane will need to know about upcoming lane changes on other lanes so they can expect an increase in merging traffic. Nickshanks 09:25, 24 March 2010 (UTC)