- if gpx.actual_points > 0
- max_lat = Tracepoint.maximum('latitude', :conditions => ['gpx_id = ?', id])
- min_lat = Tracepoint.minimum('latitude', :conditions => ['gpx_id = ?', id])
- max_lon = Tracepoint.maximum('longitude', :conditions => ['gpx_id = ?', id])
- min_lon = Tracepoint.minimum('longitude', :conditions => ['gpx_id = ?', id])
-
- 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
- self.large_picture = gpx.get_picture(min_lat, min_lon, max_lat, max_lon, gpx.actual_points)
- self.icon_picture = gpx.get_icon(min_lat, min_lon, max_lat, max_lon)
- self.size = gpx.actual_points
- self.inserted = true
- self.save!
+ f_lat = 0
+ f_lon = 0
+ first = true
+
+ # If there are any existing points for this trace then delete
+ # them - we check for existing points first to avoid locking
+ # the table in the common case where there aren't any.
+ if Tracepoint.exists?(['gpx_id = ?', self.id])
+ Tracepoint.delete_all(['gpx_id = ?', self.id])
+ end
+
+ gpx.points do |point|
+ if first
+ f_lat = point['latitude']
+ f_lon = point['longitude']
+ first = false