Postprocessing

Martin's postprocessing pipeline can transform tiles on the fly, before they are served.

Currently configurable:

convert_to_mlt - encoder settings for MVT->MLT conversion (triggered by Accept: application/vnd.maplibre-tile). See the MVT/MLT conversion guide.
convert_to_mvt - enables MLT->MVT conversion (triggered by Accept: application/x-protobuf on an MLT source). Currently only supports auto.
convert_to_hillshade - bakes a hillshade from a source serving Mapzen normal tiles. Unlike the two above, this is settable per source only, since it describes what a source serves rather than a server-wide policy.
convert_to_contour - traces contour lines from a source serving Mapzen Terrarium elevation tiles, and serves them as MVT. Settable per source only, for the same reason. See the contour guide.

The two conversion keys can be set globally, per source type, or per source. The most specific level that sets either key decides both, and levels are never merged.

convert_to_mlt:
  tessellate: true

mbtiles:
  sources:
    roads:
      path: /data/roads.mbtiles

pmtiles:
  convert_to_mlt:
    allow_fsst: false
  sources:
    basemap:
      path: /data/basemap.pmtiles
    legacy:
      path: /data/legacy.pmtiles
      convert_to_mlt: disabled
    archive:
      path: /data/archive.pmtiles
      convert_to_mvt: auto