Buildings from ways and multipolygons are loaded in table `osm_building_polygon`. But a table for `osm_building_multipolygon` is also loaded, the content is not used except to ensure an `osm_id` is from a multipolygon. To check if the object is from a multipolygon we have only to check if `osm_id` is negative. It is the counter part of e0c8ece375/layers/building/building.sql (L89)
I checked the objects are the same after this change.
Minor code cleanup:
SQL already returns NULL in the "WHEN" condition
if it is not matched by any of the cases.
Co-authored-by: Eva Jelinkova <evka.jelinkova@gmail.com>
* Add better support for 3d buildings
Change key from "levels" to "building:levels" as the "levels" key is non-standard and sees much less use than "building:levels"
* Fix typo in sql definition and missing render_min_height
* Add render_height and min_height to building.yaml
* Simplify the render, switch numeric to int.
Assume min_height cannot be negative. There are a few examples in overpass, but can't show below ground anyways in mapbox (https://github.com/mapbox/mapbox-gl-js/issues/3456). Also don't attempt to fix min_height>height
* Remove colour as it is not currently used
