Class: Feature

Inherits:
ActiveRecord::Base
  • Object
show all
Defined in:
lib/spatial_features/models/feature.rb

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.cache_derivatives(options = {}) ⇒ Object 



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# File 'lib/spatial_features/models/feature.rb', line 43

def self.cache_derivatives(options = {})
  options.reverse_merge! :lowres_simplification => 0.0001, :lowres_precision => 5

  update_all("geom        = ST_Transform(geog::geometry, 26910),
              geog_lowres = ST_SimplifyPreserveTopology(geog::geometry, #{options[:lowres_simplification]})"
              .squish)
  update_all("kml         = ST_AsKML(features.geog, 6),
              kml_lowres  = ST_AsKML(geog_lowres::geometry, #{options[:lowres_precision]})"
              .squish)
end

.invalid ⇒ Object 



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# File 'lib/spatial_features/models/feature.rb', line 30

def self.invalid
  select('features.*, ST_IsValidReason(geog::geometry) AS invalid_geometry_message').where.not('ST_IsValid(geog::geometry)')
end

.lines ⇒ Object 



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# File 'lib/spatial_features/models/feature.rb', line 22

def self.lines
  where(:feature_type => 'line')
end

.points ⇒ Object 



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# File 'lib/spatial_features/models/feature.rb', line 26

def self.points
  where(:feature_type => 'point')
end

.polygons ⇒ Object 



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# File 'lib/spatial_features/models/feature.rb', line 18

def self.polygons
  where(:feature_type => 'polygon')
end

.with_metadata(k, v) ⇒ Object 



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# File 'lib/spatial_features/models/feature.rb', line 10

def self.with_metadata(k, v)
  if k.present? && v.present?
    where('metadata->? = ?', k, v)
  else
    all
  end
end

Instance Method Details

#cache_derivatives(*args) ⇒ Object 



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# File 'lib/spatial_features/models/feature.rb', line 54

def cache_derivatives(*args)
  self.class.where(:id => self.id).cache_derivatives(*args)
end

#envelope(buffer_in_meters = 0) ⇒ Object 



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# File 'lib/spatial_features/models/feature.rb', line 34

def envelope(buffer_in_meters = 0)
  envelope_json = JSON.parse(self.class.select("ST_AsGeoJSON(ST_Envelope(ST_Buffer(features.geog, #{buffer_in_meters})::geometry)) AS result").where(:id => id).first.result)
  envelope_json = envelope_json["coordinates"].first

  raise "Can't calculate envelope for Feature #{self.id}" if envelope_json.blank?

  return envelope_json.values_at(0,2)
end

#kml(options = {}) ⇒ Object 



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# File 'lib/spatial_features/models/feature.rb', line 58

def kml(options = {})
  options[:lowres] ? kml_lowres : super()
end