Get a Relation as a Centroid "Point"

[BenOnTrack]

Node and (multipolygon) ways can easily be written into a "centroid" point using the LayerAscentroid function.

I'm curious if that is supposed to work on relation too ?

For instance, I'd like to cover such "object" into a single point -> https://www.openstreetmap.org/relation/10621048

So I'm calling the same function under the relation_function() (while making sure that it's been catched prior via the relation_scan_function().

function relation_function()
  if Find("boundary")=="protected_area" then
    LayerAsCentroid("national_park")
  end
end

it seems to be working (I do manage to see 2 new POI on my map) but to the expense of 30mb increase (for 2 relations -> I'm printing the ID each time my function is called and confirm only 2 relations are processed) !

Am I doing anything wrong ?

[SomeoneElseOSM]

https://www.openstreetmap.org/relation/10621048 is a valid multipolygon, so I'd expect it to work. I use LayerAscentroid extensively and haven't noticed problems with it. For example, https://map.atownsend.org.uk/vector/index.html#13.29/54.20748/-1.38897 is a multipolygon relation; the National Parks at https://map.atownsend.org.uk/vector/index.html#7.84/54.192/-1.9 are boundary relations.

One thing that I did notice (alas can't remember where) was that if you ask Tilemaker to write an area geometry for something that's not quite a valid area, it'll have a go - I added a bunch of IsClosed() checks to make sure I was not processing things that weren't really areas. Not sure on the impact of LayerAscentroid though.

[systemed]

Any relation whose type is multipolygon or boundary is in fact handled by way_function rather than relation_function. So you should be able just to include this in your way_function without relation-specific code.

[BenOnTrack]

Thank you guys! I confirm it's working.