[OSM-dev] osm2pgsql Lua tag transformations

[nebulon42]

Hi,

I'm currently experimenting with Lua tag transformations when importing 
data with osm2pgsql and trying to remove members of type=route relations 
(public transport routes) that have the role platform from 
planet_osm_line. The problem I'm trying to avoid can be seen here: 
https://www.openstreetmap.org/#map=18/48.19117/16.34794&layers=T 
(platforms coloured like routes)

I thought that when I set membersuperseded = 1 for the corresponding 
relation members in filter_tags_relation_member this would work, but 
apparently it isn't.

Here is the relevant part of the function:

function filter_tags_relation_member (keyvalues, keyvaluemembers, roles, 
membercount)
    ...

    membersuperseded = {}
    for i = 1, membercount do
       membersuperseded[i] = 0
    end

    ...

   if (type == "route") then
     linestring = 1
     for i = 1,membercount do
       if (roles[i] == "platform") then
         membersuperseded[i] = 1
       end
     end
   end

   ...

end

What am I doing wrong? It is possible that I'm thinking in totally wrong 
directions, any hint is appreciated.

Best, nebulon42