i’m new to OSM coming after over 10 years in Wikimapia, Can you help me with something regarding Sydney.
when you search for Sydney you get this object (13766899) but the polygon is in another object which is Sydney (5750005) (as label). is there’s a way to merge these two into one?
i spent a lot of time Fixing Sydney boundary to make it match Metro area set by ABS (excluding Central coast) but then i noticed when you search for Sydney you get one place with the name and the polygon is somewhere else. Unlike in Melbourne it’s all in one object.
Because the node is a member of the relation, they are linked and can be interpreted as different geographic representations (one being an area, one being a point) of the one place=city object, and so they are already “merged”.
The place=city Sydney extend like many things can be subjective, so best to discuss it within the community before making extensive changes, indeed your changes made 30 minutes ago are significant changes and should be discussed.
Personally I don’t think they should match ABS data for the sake of it, anyone who want’s that exact definition can fetch it from ABS, rather we should be aiming for the geographical extent of the Sydney area. Your changes made it look like
The reason was old area included places like Katoomba but not places like Wilton and Appin which are main growth areas for Sydney, i might be wrong but i think Sydney should be represented by it’s Metroplitan boundaries which Include Wollondilly shire, Blue mountains and Hawkesbury shire. In Melbourne the Metropolitan area boundaries were used not the SUA unlike in Sydney, Happy for whoever to revert my changes if Majority don’t agree. OSM seems very complicated i guess i’ll stay in Wikimapia. cheers.
In my personal opinion, it would be best to use either the Urban Centres and Localities boundary or Significant Urban Area boundary. The problem is that the GCCSA boundary is a bit too large - especially considering it encompasses a lot of undeveloped land.
Sorry for the mess i created. i wanted to help, i just found it strange that Melbourne and Brissy used GCCSA boundaries while in Sydney SUA was used. please feel free to reverse what i did, i’m not familiar with reversing sets in OSM. cheers.
What is this “metropolitan boundary” you’re referring to? Are you classifying each LGA as “metropolitan” and then just going by the extent of the “metropolitan” LGAs?
LGAs are administrative boundaries, which we map as boundary=administrative distinct from urban places like cities which we map as place=city, indeed the place=city for Sydney has no formal/administrative definition.
It’s a fair point to raise, and it’s good to discuss it first. The way I see, place=city represents the urban area, and as urban growth and sprawl expands outwards it swallows up towns that were once not part of Sydney, into part of Sydney.
If we want to have the boundaries of cities in OSM then we have at least two requirements:
A consistent definition of what a city boundary is. Global is a hopeless case, at least across Australia wold be ideal, and failing that at least across a state.
well 4-5 hours of work down the drain but it is what it is, at least when you search for Sydney now the boundaries also show automatically. i will mention this for the last time, It is strange why in Melbourne and Brisbane GCCSA boundaries were used but in Sydney SUA boundaries were used. Areas like Appin and Wilton which are major growth areas are not included with Sydney but Katoomba up the mountains is! make it make sense.!
If you’re making a fairly significant change like this, and going to spend a bit of time on the edit, it’s best to consult other mappers for feedback on your plan first.
It ensures you’re on the right track and it might even raise things you hadn’t thought of that could improve the changes. Even if it’s all positive feedback in support of the change, then that gives you community backing and more protection from your changes being immediately rolled back.
How the Australian city boundaries should be mapped is a good question, and we currently don’t have much documented in the Australian Tagging Guidelines, so I’d encourage if you feel it should be done a particular way then make your arguments for it
No matter what we do, different use cases will prefer different representations. I think it’s not a terrible idea to consider having a few different representations based on different criteria, we might only have one place=city relation, but we could have something like experimental:abc:place=city for alternative relations…
