Class: Contrek::Concurrent::GeoJsonStreamingMerger

Inherits:
StreamingMerger show all
Defined in:
lib/contrek/finder/concurrent/geo_json_streaming_merger.rb

Instance Attribute Summary

Attributes inherited from Merger

#tiles

Attributes included from Poolable

#number_of_threads

Attributes inherited from Finder

#maximum_width, #options

Instance Method Summary collapse

Methods inherited from StreamingMerger

#add_tile, #process_info

Methods inherited from VerticalMerger

#add_tile, #process_info, #transpose?

Methods inherited from Merger

#add_tile, #process_info

Methods included from Poolable

#enqueue!, #wait!

Methods inherited from Finder

#process_info, #transpose?

Constructor Details

#initialize(stream_to:, pixel_val:, options: {}) ⇒ GeoJsonStreamingMerger

Returns a new instance of GeoJsonStreamingMerger.



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# File 'lib/contrek/finder/concurrent/geo_json_streaming_merger.rb', line 6

def initialize(stream_to:, pixel_val:, options: {})
  @pixel_val = pixel_val
  super(stream_to:, options:)
end

Instance Method Details

#stream_raw_polygon(shape) ⇒ Object 



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# File 'lib/contrek/finder/concurrent/geo_json_streaming_merger.rb', line 20

def stream_raw_polygon(shape)
  if @first_feature
    @first_feature = false
  else
    @stream.write(",")
  end
  outer_ring = shape.outer_polyline.raw.map { |p| [p[:y], p[:x]] }
  outer_ring << outer_ring.first if outer_ring.first != outer_ring.last
  polygon_coordinates = [outer_ring]
  shape.inner_polylines.map(&:raw).each do |sequence|
    inner_ring = sequence.map { |p| [p[:y], p[:x]] }
    inner_ring << inner_ring.first if inner_ring.first != inner_ring.last
    polygon_coordinates << inner_ring
  end
  feature_hash = {
    type: "Feature",
    properties: {PixelVal: @pixel_val},
    geometry: {
      type: "Polygon",
      coordinates: polygon_coordinates
    }
  }
  @stream.write(JSON.generate(feature_hash))
end

#write_footer ⇒ Object 



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# File 'lib/contrek/finder/concurrent/geo_json_streaming_merger.rb', line 16

def write_footer
  @stream.write("]}")
end

#write_header ⇒ Object 



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# File 'lib/contrek/finder/concurrent/geo_json_streaming_merger.rb', line 11

def write_header
  @first_feature = true
  @stream.write("{\"type\":\"FeatureCollection\",\"features\":[")
end