Inverting y coordinate

2018-05-08 16:54:53 +02:00 · 2018-05-08 16:54:53 +02:00 · 3fba8a3091
commit 3fba8a3091
parent fafd4a364e
1 changed files with 1 additions and 0 deletions
--- a/src/pg/sql/45_observatory_mvt.sql
+++ b/src/pg/sql/45_observatory_mvt.sql
@ -3,6 +3,7 @@ RETURNS NUMERIC[] AS $$
 import math
 def tile2lnglat(z, x, y):
    n = 2.0 ** z
+    y = (1 << z) - y - 1

    lon = x / n * 360.0 - 180.0
    lat_rad = math.atan(math.sinh(math.pi * (1 - 2 * y / n)))