From: Anton Khorev <tony29@yandex.ru>
Date: Fri, 16 Aug 2024 07:45:54 +0000 (+0300)
Subject: Change zoom precision function
X-Git-Tag: live~310^2
X-Git-Url: https://git.openstreetmap.org./rails.git/commitdiff_plain/1951ed2eb8af93d71e4d10ce0ede81d3ee2090bd?hp=9b2db63a957a325d16e3989f08c483bd88f1993e

Change zoom precision function

This changes the number of fractional digits to log10(pixels / degrees) with pixels = 2**(8 + zoom) and degrees = 180.
---

diff --git a/app/assets/javascripts/osm.js.erb b/app/assets/javascripts/osm.js.erb
index e429f4479..e08528f84 100644
--- a/app/assets/javascripts/osm.js.erb
+++ b/app/assets/javascripts/osm.js.erb
@@ -204,7 +204,9 @@ OSM = {
   },
 
   zoomPrecision: function(zoom) {
-    return Math.max(0, Math.ceil(Math.log(zoom) / Math.LN2));
+    var pixels = Math.pow(2, 8 + zoom);
+    var degrees = 180;
+    return Math.ceil(Math.log10(pixels / degrees));
   },
 
   locationCookie: function(map) {