The Future of Areas/Relation alternatives to Multipolygons

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Alternatives to Multipolygons

Currently the multipolygon is the only way to define an area besides the simple closed way flagged as area=yes. It would be nice to have another type of area definition for some cases, where explicit polygons are confusing and not representing reality in a nice way.

1. Area relation

Proposal

Usecases

  • riverbank. Dividing the river area in arbitrary pieces like we do it now makes no sense
  • linear highway-areas (street areas) (the same argument as for rivers, plus it is potentially error attracting to have orthogonal division (wrong connections))
  • area steps

How it would be done

An alternative method to define areas would be to have two ways (or continuous groups of ways), normally somehow parallel, but even an intersection of one with the other would not harm, and then interpolate the area between them (virtually connect the endpoints but don't require the mapper to do this). Maybe for crossings it would be needed to do this interpolation also on more than two way groups (e.g. four ordered way groups). (Note: way group here means one or more ways directly attached and continuous, not self-intersecting).)

Routing

This area type defines the area as routable, i.e. even if the ways are not connected routing software should assume that you can change from one way to the other.