Ruby on GeoTools で境界ボックスフィルタ
geotools.rb の Geo::Reader に境界ボックスフィルタを実装しました。
Geo::Reader#foreach の第二引数 options に、{:bbox => [136, 35, 137, 36]} のように境界ボックスを指定します。境界ボックスは要素数４の配列で、[xmin, ymin, xmax, ymax] の順番で記述してください。
現時点で options に使えるキーとその値をまとめると、以下のようになります。
| キー | 値 |
| :sjis_workaround | true のとき、Shift_JIS の主題属性を (UTF-8)文字列として戻すようにします。 |
| :whitelist | Ruby レベルまで取り出す属性名を配列として渡します。例 {:whitelist => ['exs]} |
| :bbox | 取り出すデータの空間範囲を、[xmin, ymin, xmax, ymax] という配列で]指定します。例 {:bbox => [136 35 137 36]} |
利用
以下のようなコードで、本エントリの画像のように、Shapefile の一部分を別の Shapefile に切り出すことができます。
require 'geotools' src = '../transl_1_1.shp' xmin = 136 ymin = 35 xmax = 137 ymax = 36 Geo::Writer::open('bbox_box.shp') do |w| w.write(Geo::bbox2polygon([xmin, ymin, xmax, ymax])) end Geo::Writer::open('bbox.shp') do |w| Geo::Reader::foreach(src, {:whitelist => [], :bbox => [xmin, ymin, xmax, ymax]}) do |geom, attrs| w.write(geom) end end
境界にかかるデータも、特にはみ出し部分を取り除いたりすることなく、そのまま含まれます。
geotools.rb
現時点での geotools.rb の内容は、以下の通りです。境界ボックスフィルタを実装したほか、Geo::bbox2polygon などの、比較的自明なメソッドを追加したりしています。
# this code is under development and subject to major change. require 'iconv' module Geo # Geo::Tools module, to include nesessary classes from Geotools module Tools QUALIFIED_NAMES = %w{java.lang.System java.lang.String java.lang.Integer java.lang.Double java.lang.Long java.io.File java.util.HashMap org.geotools.data.shapefile.ShapefileDataStore org.geotools.feature.AttributeTypeFactory org.geotools.feature.FeatureTypeBuilder org.geotools.feature.type.GeometricAttributeType com.vividsolutions.jts.io.WKTReader org.geotools.referencing.crs.EPSGCRSAuthorityFactory org.geotools.referencing.operation.DefaultCoordinateOperationFactory org.geotools.geometry.DirectPosition2D org.geotools.data.vpf.file.VPFFile org.geotools.data.vpf.VPFLibrary org.geotools.gce.geotiff.GeoTiffWriter org.geotools.gce.geotiff.GeoTiffWriteParams org.geotools.coverage.grid.GridCoverageFactory com.vividsolutions.jts.geom.Envelope org.geotools.geometry.Envelope2D org.geotools.factory.Hints org.geotools.geometry.jts.JTS org.geotools.filter.text.cql2.CQL} begin require 'rjb' QUALIFIED_NAMES.each do |qn| sn = qn.split('.').last module_eval "#{sn} = Rjb::import('#{qn}')" end IMPLEMENTATION = 'rjb' rescue LoadError require 'java' QUALIFIED_NAMES.each do |qn| include_class qn end IMPLEMENTATION = 'java' end end # Geo module variables @@wkt_reader = nil @@epsg_crs_authority_factory = nil # Geo module 'good-wrapper' / 'Grossklasstum' classes class Reader if Tools::IMPLEMENTATION == 'java' print "DEBUG: jruby mode\n" def iterate while(@iter.hasNext) feat = @iter.next attrs = {} @attr_names.each do |attr_name| attrs[attr_name] = feat.getAttribute(attr_name) end yield feat.getDefaultGeometry, attrs end end else begin Rjb::primitive_conversion = true print "DEBUG: rjb primitive_conversion mode\n" def iterate while(@iter.hasNext) feat = @iter.next attrs = {} @attr_names.each do |attr_name| attr = feat.getAttribute(attr_name) if attr.respond_to?('_invoke') # java.lang.String を変換 attr = attr.toString if attr.getClass == Geo::Tools::String end # 今のところ、これで遅くなっている attrs[attr_name] = attr end yield feat.getDefaultGeometry, attrs end end rescue NoMethodError print "DEBUG: rjb conventional mode\n" def iterate while(@iter.hasNext) feat = @iter.next attrs = {} @attr_names.each do |attr_name| attr = feat.getAttribute(attr_name) if attr.getClass.equals(Tools::Integer) attr = attr.intValue elsif attr.getClass.equals(Tools::Double) attr = attr.doubleValue elsif attr.getClass.equals(Tools::String) if @sjis_workaround attr = Iconv.conv('UTF-8', 'Shift_JIS', attr.getBytes('iso-8859-1')) else attr = attr.toString end elsif attr.getClass.equals(Tools::Long) attr = attr.longValue end attrs[attr_name] = attr end yield feat.getDefaultGeometry, attrs end end end end # keys for options: :sjis_workaround (boolean), :whitelist (array) # :bbox (array [xmin, ymin, xmax, ymax]) def Reader::foreach(shapefile, options = {}) r = Reader.new(shapefile, options) r.iterate do |geom, attrs| yield geom, attrs end r.close end def initialize(shapefile, options = {}) @sjis_workaround = options[:sjis_workaround] @sjis_workaround = false if @sjis_workaround == nil if(Tools::IMPLEMENTATION == 'java' && @sjis_workaround) raise "sjis_workaround for JRuby is not implemented." end store = Tools::ShapefileDataStore.new(Tools::File.new(shapefile).toURL) if options.has_key?(:bbox) b = options[:bbox] f = Geo::Tools::CQL::toFilter("BBOX(the_geom, #{b[0]}, #{b[1]}, #{b[2]}, #{b[3]})") # TODO: NONE and ALL are warned to be already initialized constants [Rjb] @iter = store.getFeatureSource.getFeatures(f).features else @iter = store.getFeatureSource.getFeatures.features end feat_type = store.getFeatureSource.getSchema if options[:whitelist] == nil @attr_names = [] feat_type.getAttributeCount.times do |i| name = feat_type.getAttributeType(i).getName @attr_names << name unless name == 'the_geom' end else @attr_names = options[:whitelist] #TODO: whitelist checking necessary? end end def close @iter.close end end class Writer def Writer::open(shapefile) w = Writer.new(shapefile) yield w w.close end def initialize(shapefile) @shapefile = shapefile @writer = nil @first = true end def setup(geom, attrs) attrs.delete('the_geom') ftb = Tools::FeatureTypeBuilder.newInstance(@shapefile) attrs.each do |key, value| if value.methods.include?('_classname') attr_class = value.getClass elsif value.class == String attr_class = Tools::String elsif value.class == Fixnum attr_class = Tools::Integer elsif value.class == Float attr_class = Tools::Double else raise "attribute #{key} has unrecognizable class #{value.class}" end ftb.addType(Tools::AttributeTypeFactory.newAttributeType(key, attr_class)) end if geom.class == String geom = import_wkt_geometry(geom) end ftb.setDefaultGeometry(Tools::GeometricAttributeType.new('the_geom', geom.getClass, true, nil, nil, nil)) ft = ftb.getFeatureType store = Tools::ShapefileDataStore.new(Tools::File.new(@shapefile).toURL) store.createSchema(ft) @writer = store.getFeatureWriter(@shapefile, store.getFeatureSource(@shapefile).getTransaction) @first = false end private :setup def write(geom, attrs = {}) setup(geom, attrs) if @first feat = @writer.next if geom.class == String geom = import_wkt_geometry(geom) end feat.setDefaultGeometry(geom) attrs.each do |key, value| feat.setAttribute(key, value) end @writer.write end def close @writer.close unless @writer == nil end end class Transform def initialize(src_crs, dst_crs) cof = Geo::Tools::DefaultCoordinateOperationFactory.new @co = cof.createOperation(src_crs, dst_crs) @mt = @co.getMathTransform end def transform(x, y) # z? r = Geo::Tools::DirectPosition2D.new @mt.transform(Geo::Tools::DirectPosition2D.new(x, y), r) return r.x, r.y end def transform(geom) Geo::Tools::JTS::transform(geom, @mt) end ## TODO: accessor to @mt or @co end # create GridCoverage of buf which just fits bbox def Geo::create_grid_coverage(buf, crs, bbox) Geo::Tools::System::setProperty('com.apple.eawt.CocoaComponent.CompatibilityMode', 'false') f = Tools::GridCoverageFactory.new n_pix_x = buf[0].size n_pix_y = buf.size env = Tools::Envelope2D.new(crs, bbox[0] - (bbox[2] - bbox[0]) / n_pix_x / 2, bbox[1] + (bbox[3] - bbox[1]) / n_pix_y / 2, bbox[2] - bbox[0], bbox[3] - bbox[1]) if Tools::IMPLEMENTATION == 'java' f.create('', buf.to_java(:float), env) else f._invoke('create', 'Ljava.lang.CharSequence;[[FLorg.opengis.geometry.Envelope;', '', buf, env) end end def Geo::write_grid_coverage(coverage, filename) w = Tools::GeoTiffWriter.new(Tools::File.new(filename)) # p = Tools::GeoTiffWriteParams.new # p.setCompressionMode(Tools::GeoTiffWriteParams.MODE_EXPLICIT) # p.setCompressionType('LZW') # p.setCompressionQuality(0.75) # format = w.getFormat ### -> rt.java problem: no sun.jdbc.odbc.ee.DataSource for Mac OS X ### so, no compression for GeoTiff file # params = format.getWriteParameters # params.parameter( # format.GEOTOOLS_WRITE_PARAMS.getName.toString).setValue(p) # w.write(coverage, params.values.toArray) w.write(coverage, nil) end # Geo module convenient methods def Geo::import_wkt_geometry(wkt) @@wkt_reader = Geo::Tools::WKTReader.new if @@wkt_reader == nil @@wkt_reader.read(wkt) end def Geo::import_epsg_crs(epsg_code) @@epsg_crs_authority_factory = Geo::Tools::EPSGCRSAuthorityFactory.new if @@epsg_crs_authority_factory == nil if epsg_code.class == Fixnum return @@epsg_crs_authority_factory.createCoordinateReferenceSystem("EPSG:#{epsg_code}") elsif epsg_code.class == String return @@epsg_crs_authority_factory.createCoordinateReferenceSystem(epsg_code) else raise "Geo::import_epsg_crs: can not handle epsg_code = #{epsg_code}" end end def Geo::bbox2polygon(b) Geo::import_wkt_geometry("POLYGON ((#{b[0]} #{b[1]}, #{b[2]} #{b[1]}, #{b[2]} #{b[3]}, #{b[0]} #{b[3]}, #{b[0]} #{b[1]}))") end def dms2dec(d, m, s) d + m / 60.0 + s / 3600.0 end def dec2dms(dec) #TODO raise "not implemented." end end # ad hoc tests if __FILE__ == $0 ## TODO: better separate tests as unit tests. start_time = Time.now Geo::Writer.open('test.shp') do |w| Geo::Reader.foreach('transl_1_1.shp', {:whitelist => ['exs', 'soc'], :bbox => [135, 35, 136, 36]}) do |geom, attrs| #print "#{attrs.inspect}\n" w.write(geom, attrs) end end print "#{Time.now - start_time} sec.\n" exit # ここから下は別の話題 ix = Geo::import_epsg_crs(2451) # EPSG:2451 - 平面直角座標系 IX 系 wgs84 = Geo::import_epsg_crs(4326) # EPSG:4326 - WGS84 t = Geo::Transform.new(ix, wgs84) # IX 系から WGS84 への座標変換器 t_inv = Geo::Transform.new(wgs84, ix) # WGS84 から IX 系への座標変換器 pt = t.transform(0, 0) # IX 系の原点を WGS84 に座標変換 pt_inv = t_inv.transform(pt[0], pt[1]) # その点を IX 系に戻す。元に戻るか? print "IX origin is #{pt.inspect} in WGS84\n" print "#{pt_inv.inspect} must be (0, 0)\n" end
TODO
Rjb 版で :bbox 指定をすると、Geo::Tools::CQL::toFilter を実行するところで、「NONE と ALL はすでに初期化された定数である」という警告が出ます：
$ ruby bbox.rb DEBUG: rjb primitive_conversion mode /opt/local/lib/ruby/site_ruby/1.8/i686-darwin8.9.1/geotools.rb:108: warning: already initialized constant NONE /opt/local/lib/ruby/site_ruby/1.8/i686-darwin8.9.1/geotools.rb:108: warning: already initialized constant ALL
JRuby ではこの警告は出ません。この原因はあとで調べるかもしれませんし、この警告を表示しないようにする姑息な手段を講じたりするかもしれません。
