diff options
| -rw-r--r-- | plugin.rb | 72 |
1 files changed, 68 insertions, 4 deletions
@@ -2,16 +2,80 @@ # version: 0.1 # authors: Marcin Rataj -# whitelist raw iframes +# whitelist raw iframes posted by users register_asset('javascripts/iframe_whitelist.js', :server_side) class Onebox::Engine::OpenStreetMapOnebox include Onebox::Engine - # oneboxing canonical links into iframes - matches_regexp(/^https?:\/\/(?:www\.)?(?:openstreetmap\.org\/\?mlat)\/.+$/) + # current embed defaults from openstreetmap.org + @@width = 425 + @@height = 350 + @@tile_size = 256 + + + # enable oneboxing permalinks (http://wiki.openstreetmap.org/wiki/Permalink) into iframes + matches_regexp(/^https?:\/\/(?:www\.)openstreetmap\.org/) def to_html - "<iframe src='#{@url}' style='border: 0' width='100%' height='350' frameborder='0' scrolling='no'></iframe>" + if match = @url.match(/#map=([\d\.]+)\/([\d\.]+)\/([\d\.]+)/) + zoom, lat, lon = match.captures + iframe_url = "//www.openstreetmap.org/export/embed.html?bbox=#{get_bbox(lat.to_f, lon.to_f, zoom.to_i)}" + + if marker = @url.match(/mlat=([\d\.]+).+mlon=([\d\.]+)/) + mlat, mlon = marker.captures + iframe_url = "#{iframe_url}&marker=#{mlat}%2C#{mlon}" + end + + "<iframe src='#{iframe_url}' style='border: 0' width='#{@@width.to_i}' height='#{@@height.to_i}' frameborder='0' scrolling='no'></iframe>" + else + #"NOPE" #@url + @url + end + end + + private + + # http://wiki.openstreetmap.org/wiki/Slippy_map_tilenames#Lon..2Flat._to_tile_numbers_3 + # note: it is slightly modified as fractional part is not discarded (http://goo.gl/oNtQ5g) + def get_tile_number(lat_deg, lng_deg, zoom) + lat_rad = lat_deg/180 * Math::PI + n = 2.0 ** zoom + x = (lng_deg + 180.0) / 360.0 * n + y = (1.0 - Math::log(Math::tan(lat_rad) + (1 / Math::cos(lat_rad))) / Math::PI) / 2.0 * n + if !y.infinite?.nil? + y = x + end + + [x, y] end + + # http://wiki.openstreetmap.org/wiki/Slippy_map_tilenames#Tile_numbers_to_lon..2Flat._3 + def get_lat_lng_for_number(xtile, ytile, zoom) + n = 2.0 ** zoom + lon_deg = xtile / n * 360.0 - 180.0 + lat_rad = Math::atan(Math::sinh(Math::PI * (1 - 2 * ytile / n))) + lat_deg = 180.0 * (lat_rad / Math::PI) + + [lat_deg, lon_deg] + end + + # http://wiki.openstreetmap.org/wiki/Slippy_map_tilenames#Lon..2Flat._to_bbox + def get_bbox(lat, lon, zoom) + + xtile, ytile = get_tile_number(lat, lon, zoom) + + xtile_s = (xtile * @@tile_size - @@width/2.0) / @@tile_size + ytile_s = (ytile * @@tile_size - @@height/2.0) / @@tile_size + xtile_e = (xtile * @@tile_size + @@width/2.0) / @@tile_size + ytile_e = (ytile * @@tile_size + @@height/2.0) / @@tile_size + + lat_s, lon_s = get_lat_lng_for_number(xtile_s, ytile_s, zoom) + lat_e, lon_e = get_lat_lng_for_number(xtile_e, ytile_e, zoom) + + "#{lon_s}%2C#{lat_s}%2C#{lon_e}%2C#{lat_e}" + end + end + +# vim:ts=2:sw=2:et: |