class BoundingBox
- def initialize(min_lon, min_lat, max_lon, max_lat)
- @bbox = [min_lon.to_f, min_lat.to_f, max_lon.to_f, max_lat.to_f]
- end
-
- def self.from_s(s)
- BoundingBox.new(*s.split(/,/))
- end
-
- def min_lon
- @bbox[0]
- end
-
- def min_lon=(min_lon)
- @bbox[0] = min_lon
- end
-
- def min_lat
- @bbox[1]
- end
-
- def min_lat=(min_lat)
- @bbox[1] = min_lat
- end
+ attr_reader :min_lon, :min_lat, :max_lon, :max_lat
- def max_lon
- @bbox[2]
- end
-
- def max_lon=(max_lon)
- @bbox[2] = max_lon
- end
+private
+ LON_LIMIT = 180.0
+ LAT_LIMIT = 90.0
+ SCALED_LON_LIMIT = LON_LIMIT * GeoRecord::SCALE
+ SCALED_LAT_LIMIT = LAT_LIMIT * GeoRecord::SCALE
- def max_lat
- @bbox[3]
+public
+ def initialize(min_lon, min_lat, max_lon, max_lat)
+ @min_lon = min_lon.to_f unless min_lon.nil?
+ @min_lat = min_lat.to_f unless min_lat.nil?
+ @max_lon = max_lon.to_f unless max_lon.nil?
+ @max_lat = max_lat.to_f unless max_lat.nil?
end
- def max_lat=(max_lat)
- @bbox[3] = max_lat
+ def self.from_s(s)
+ if s.count(',') == 3
+ BoundingBox.new(*s.split(/,/))
+ else
+ nil
+ end
+ end
+
+ def self.from_bbox_params(params)
+ if params[:bbox] and params[:bbox].count(',') == 3
+ bbox_array = params[:bbox].split(',')
+ end
+ from_bbox_array(bbox_array)
+ end
+
+ def self.from_lon_lat_params(params)
+ if params[:minlon] and params[:minlat] and params[:maxlon] and params[:maxlat]
+ bbox_array = [params[:minlon], params[:minlat], params[:maxlon], params[:maxlat]]
+ end
+ from_bbox_array(bbox_array)
+ end
+
+ def expand!(bbox, margin = 0)
+ update!(bbox) unless complete?
+ # only try to expand the bbox if there is a value for every coordinate
+ # which there will be from the previous line as long as array does not contain a nil
+ if bbox.complete?
+ @min_lon = [-SCALED_LON_LIMIT,
+ bbox.min_lon + margin * (min_lon - max_lon)].max if bbox.min_lon < min_lon
+ @min_lat = [-SCALED_LAT_LIMIT,
+ bbox.min_lat + margin * (min_lat - max_lat)].max if bbox.min_lat < min_lat
+ @max_lon = [+SCALED_LON_LIMIT,
+ bbox.max_lon + margin * (max_lon - min_lon)].min if bbox.max_lon > max_lon
+ @max_lat = [+SCALED_LAT_LIMIT,
+ bbox.max_lat + margin * (max_lat - min_lat)].min if bbox.max_lat > max_lat
+ end
+ self
+ end
+
+ def check_boundaries
+ # check the bbox is sane
+ if min_lon > max_lon
+ raise OSM::APIBadBoundingBox.new(
+ "The minimum longitude must be less than the maximum longitude, but it wasn't")
+ end
+ if min_lat > max_lat
+ raise OSM::APIBadBoundingBox.new(
+ "The minimum latitude must be less than the maximum latitude, but it wasn't")
+ end
+ if min_lon < -LON_LIMIT || min_lat < -LAT_LIMIT || max_lon > +LON_LIMIT || max_lat > +LAT_LIMIT
+ raise OSM::APIBadBoundingBox.new("The latitudes must be between #{-LAT_LIMIT} and #{LAT_LIMIT}," +
+ " and longitudes between #{-LON_LIMIT} and #{LON_LIMIT}")
+ end
+ self
+ end
+
+ def check_size
+ # check the bbox isn't too large
+ if area > MAX_REQUEST_AREA
+ raise OSM::APIBadBoundingBox.new("The maximum bbox size is " + MAX_REQUEST_AREA.to_s +
+ ", and your request was too large. Either request a smaller area, or use planet.osm")
+ end
+ self
+ end
+
+ ##
+ # returns area of the bbox as a rough comparative quantity
+ def area
+ if complete?
+ (max_lon - min_lon) * (max_lat - min_lat)
+ else
+ 0
+ end
+ end
+
+ def complete?
+ not to_a.include?(nil)
end
def centre_lon
- (@bbox[0] + @bbox[2]) / 2.0
+ (min_lon + max_lon) / 2.0
end
def centre_lat
- (@bbox[1] + @bbox[3]) / 2.0
+ (min_lat + max_lat) / 2.0
end
def width
- @bbox[2] - @bbox[0]
+ max_lon - min_lon
end
def height
- @bbox[3] - @bbox[1]
+ max_lat - min_lat
end
def slippy_width(zoom)
min = min_lat * Math::PI / 180.0
max = max_lat * Math::PI / 180.0
- Math.log((Math.tan(max) + 1.0 / Math.cos(max)) / (Math.tan(min) + 1.0 / Math.cos(min))) * 128.0 * 2.0 ** zoom / Math::PI
+ Math.log((Math.tan(max) + 1.0 / Math.cos(max)) /
+ (Math.tan(min) + 1.0 / Math.cos(min))) *
+ (128.0 * 2.0 ** zoom / Math::PI)
+ end
+
+ # there are two forms used for bounds with and without an underscore,
+ # cater for both forms eg minlon and min_lon
+ def add_bounds_to(hash, underscore = "")
+ hash["min#{underscore}lat"] = min_lat.to_s
+ hash["min#{underscore}lon"] = min_lon.to_s
+ hash["max#{underscore}lat"] = max_lat.to_s
+ hash["max#{underscore}lon"] = max_lon.to_s
+ hash
+ end
+
+ def to_scaled
+ BoundingBox.new((min_lon * GeoRecord::SCALE),
+ (min_lat * GeoRecord::SCALE),
+ (max_lon * GeoRecord::SCALE),
+ (max_lat * GeoRecord::SCALE))
+ end
+
+ def to_unscaled
+ BoundingBox.new((min_lon / GeoRecord::SCALE),
+ (min_lat / GeoRecord::SCALE),
+ (max_lon / GeoRecord::SCALE),
+ (max_lat / GeoRecord::SCALE))
+ end
+
+ def to_a
+ [min_lon, min_lat, max_lon, max_lat]
end
def to_s
- return @bbox.join(",")
+ "#{min_lon},#{min_lat},#{max_lon},#{max_lat}"
+ end
+
+ private
+ def self.from_bbox_array(bbox_array)
+ unless bbox_array
+ raise OSM::APIBadUserInput.new(
+ "The parameter bbox is required, and must be of the form min_lon,min_lat,max_lon,max_lat")
+ end
+ # Take an array of length 4, create a bounding box with min_lon, min_lat, max_lon and
+ # max_lat within their respective boundaries.
+ min_lon = [[bbox_array[0].to_f, -LON_LIMIT].max, +LON_LIMIT].min
+ min_lat = [[bbox_array[1].to_f, -LAT_LIMIT].max, +LAT_LIMIT].min
+ max_lon = [[bbox_array[2].to_f, +LON_LIMIT].min, -LON_LIMIT].max
+ max_lat = [[bbox_array[3].to_f, +LAT_LIMIT].min, -LAT_LIMIT].max
+ BoundingBox.new(min_lon, min_lat, max_lon, max_lat)
+ end
+
+ def update!(bbox)
+ # ensure that bbox has no nils in it. if there are any
+ # nils, just use the bounding box update to write over them.
+ @min_lon = bbox.min_lon if min_lon.nil?
+ @min_lat = bbox.min_lat if min_lat.nil?
+ @max_lon = bbox.max_lon if max_lon.nil?
+ @max_lat = bbox.max_lat if max_lat.nil?
end
end