38 lines
1.6 KiB
PL/PgSQL
38 lines
1.6 KiB
PL/PgSQL
CREATE OR REPLACE FUNCTION layer_city(bbox geometry, zoom_level int, pixel_width numeric)
|
|
RETURNS TABLE(osm_id bigint, geometry geometry, name text, name_en text, class city_class, "rank" int) AS $$
|
|
SELECT osm_id, geometry, name, COALESCE(NULLIF(name_en, ''), name) AS name_en, place AS class, "rank"
|
|
FROM osm_city_point
|
|
WHERE geometry && bbox
|
|
AND ((zoom_level = 2 AND "rank" = 1)
|
|
OR (zoom_level BETWEEN 3 AND 7 AND "rank" <= zoom_level)
|
|
)
|
|
UNION ALL
|
|
SELECT osm_id, geometry, name,
|
|
COALESCE(NULLIF(name_en, ''), name) AS name_en,
|
|
place AS class,
|
|
COALESCE("rank", gridrank + 10)
|
|
FROM (
|
|
SELECT osm_id, geometry, name, name_en, place, "rank",
|
|
row_number() OVER (
|
|
PARTITION BY LabelGrid(geometry, 128 * pixel_width)
|
|
ORDER BY "rank" ASC NULLS LAST,
|
|
place ASC NULLS LAST,
|
|
population DESC NULLS LAST,
|
|
length(name) ASC
|
|
)::int AS gridrank
|
|
FROM osm_city_point
|
|
WHERE geometry && bbox
|
|
AND ((zoom_level = 8 AND place <= 'town'::city_class)
|
|
OR (zoom_level BETWEEN 9 AND 10 AND place <= 'village'::city_class)
|
|
OR (zoom_level BETWEEN 11 AND 13 AND place <= 'suburb'::city_class)
|
|
OR (zoom_level >= 14)
|
|
)
|
|
) AS ranked_places
|
|
WHERE (zoom_level = 8 AND (gridrank <= 4 OR "rank" IS NOT NULL))
|
|
OR (zoom_level = 9 AND (gridrank <= 8 OR "rank" IS NOT NULL))
|
|
OR (zoom_level = 10 AND (gridrank <= 12 OR "rank" IS NOT NULL))
|
|
OR (zoom_level BETWEEN 11 AND 12 AND (gridrank <= 14 OR "rank" IS NOT NULL))
|
|
OR (zoom_level >= 13)
|
|
ORDER BY "rank" ASC;
|
|
$$ LANGUAGE SQL IMMUTABLE;
|