Potlatch 0.9a

[rails.git] / app / models / geo_record.rb

diff --git a/app/models/geo_record.rb b/app/models/geo_record.rb
index 12a2a643e259d5b1cccc3fabcaa49a5a64fcaf43..ddd029aec0f3db85b1b447928994eab5ac2824cc 100644 (file)
--- a/app/models/geo_record.rb
+++ b/app/models/geo_record.rb
@@ -1,6 +1,14 @@
 class GeoRecord < ActiveRecord::Base
   before_save :update_tile
 
+  # Is this node within -90 >= latitude >= 90 and -180 >= longitude >= 180
+  # * returns true/false
+  def in_world?
+    return false if self.lat < -90 or self.lat > 90
+    return false if self.lon < -180 or self.lon > 180
+    return true
+  end
+
   def self.find_by_area(minlat, minlon, maxlat, maxlon, options)
     self.with_scope(:find => {:conditions => OSM.sql_for_area(minlat, minlon, maxlat, maxlon)}) do
       return self.find(:all, options)
@@ -19,11 +27,30 @@ class GeoRecord < ActiveRecord::Base
     self.longitude = (l * 10000000).round
   end
 
+  # Return WGS84 latitude
   def lat
     return self.latitude.to_f / 10000000
   end
 
+  # Return WGS84 longitude
   def lon
     return self.longitude.to_f / 10000000
   end
+
+  # Potlatch projections
+  def lon_potlatch(baselong,masterscale)
+    (self.lon-baselong)*masterscale
+  end
+
+  def lat_potlatch(basey,masterscale)
+    -(lat2y(self.lat)-basey)*masterscale
+  end
+  
+  private
+  
+  def lat2y(a)
+    180/Math::PI * Math.log(Math.tan(Math::PI/4+a*(Math::PI/180)/2))
+  end
+
 end
+