From 9afb35449b066fdef6b4af3b63e30e7f4eb4c5cf Mon Sep 17 00:00:00 2001
From: Tom Hughes <tom@compton.nu>
Date: Tue, 18 Sep 2007 23:29:47 +0000
Subject: [PATCH] Change the gps_points table to store latitude and longitude
 values to seven decimal places to given a worse case precision of about 1cm.

---
 app/models/trace.rb                | 8 ++++----
 app/models/tracepoint.rb           | 8 ++++----
 db/functions/quadtile.c            | 2 +-
 db/migrate/005_tile_tracepoints.rb | 2 +-
 lib/osm.rb                         | 8 ++++----
 5 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/app/models/trace.rb b/app/models/trace.rb
index a2bebf1dd..4cac233c2 100644
--- a/app/models/trace.rb
+++ b/app/models/trace.rb
@@ -204,10 +204,10 @@ class Trace < ActiveRecord::Base
         max_lon = Tracepoint.maximum('longitude', :conditions => ['gpx_id = ?', id])
         min_lon = Tracepoint.minimum('longitude', :conditions => ['gpx_id = ?', id])
 
-        max_lat = max_lat.to_f / 1000000
-        min_lat = min_lat.to_f / 1000000
-        max_lon = max_lon.to_f / 1000000
-        min_lon = min_lon.to_f / 1000000
+        max_lat = max_lat.to_f / 10000000
+        min_lat = min_lat.to_f / 10000000
+        max_lon = max_lon.to_f / 10000000
+        min_lon = min_lon.to_f / 10000000
 
         self.latitude = f_lat
         self.longitude = f_lon
diff --git a/app/models/tracepoint.rb b/app/models/tracepoint.rb
index e48a2748d..e0fcfbd97 100644
--- a/app/models/tracepoint.rb
+++ b/app/models/tracepoint.rb
@@ -22,19 +22,19 @@ class Tracepoint < ActiveRecord::Base
   end
 
   def lat=(l)
-    self.latitude = (l * 1000000).round
+    self.latitude = (l * 10000000).round
   end
 
   def lng=(l)
-    self.longitude = (l * 1000000).round
+    self.longitude = (l * 10000000).round
   end
 
   def lat
-    return self.latitude.to_f / 1000000
+    return self.latitude.to_f / 10000000
   end
 
   def lon
-    return self.longitude.to_f / 1000000
+    return self.longitude.to_f / 10000000
   end
 
   def to_xml_node
diff --git a/db/functions/quadtile.c b/db/functions/quadtile.c
index c0eb1ec3a..d60189245 100644
--- a/db/functions/quadtile.c
+++ b/db/functions/quadtile.c
@@ -27,5 +27,5 @@ long long tile_for_point(UDF_INIT *initid, UDF_ARGS *args, char *is_null, char *
    long long lat = *(long long *)args->args[0];
    long long lon = *(long long *)args->args[1];
 
-   return xy2tile(lon2x(lon / 1000000.0), lat2y(lat / 1000000.0));
+   return xy2tile(lon2x(lon / 10000000.0), lat2y(lat / 10000000.0));
 }
diff --git a/db/migrate/005_tile_tracepoints.rb b/db/migrate/005_tile_tracepoints.rb
index 246f9b7b4..c0e6d8a61 100644
--- a/db/migrate/005_tile_tracepoints.rb
+++ b/db/migrate/005_tile_tracepoints.rb
@@ -4,7 +4,7 @@ class TileTracepoints < ActiveRecord::Migration
     add_index "gps_points", ["tile"], :name => "points_tile_idx"
     remove_index "gps_points", :name => "points_idx"
 
-    Tracepoint.update_all("tile = tile_for_point(latitude, longitude)")
+    Tracepoint.update_all("latitude = latitude * 10, longitude = longitude * 10, tile = tile_for_point(latitude * 10, longitude * 10)")
   end
 
   def self.down
diff --git a/lib/osm.rb b/lib/osm.rb
index 300d9fa7a..45c506e2e 100644
--- a/lib/osm.rb
+++ b/lib/osm.rb
@@ -414,10 +414,10 @@ module OSM
   # Return an SQL fragment to select a given area of the globe
   def self.sql_for_area(minlat, minlon, maxlat, maxlon, prefix = nil)
     tilesql = QuadTile.sql_for_area(minlat, minlon, maxlat, maxlon, prefix)
-    minlat = (minlat * 1000000).round
-    minlon = (minlon * 1000000).round
-    maxlat = (maxlat * 1000000).round
-    maxlon = (maxlon * 1000000).round
+    minlat = (minlat * 10000000).round
+    minlon = (minlon * 10000000).round
+    maxlat = (maxlat * 10000000).round
+    maxlon = (maxlon * 10000000).round
 
     return "#{tilesql} AND #{prefix}latitude BETWEEN #{minlat} AND #{maxlat} AND #{prefix}longitude BETWEEN #{minlon} AND #{maxlon}"
   end
-- 
2.39.5