Consider that every major map provider does this (Japanese train lines, and sometimes icons like that stylized katakana "te" for post offices). Also highway shields. Although OSM-carto is not supposed to be consumed by end-users, it often is; moreover it could be serve as an example on how to implement that (in order to encourage other OSM rendering style authors to do so).
Michał _______________________________________________ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
