class GeoScript::Projection

Attributes

crs[RW]

Public Class Methods

new(proj) click to toggle source
# File lib/geoscript/projection.rb, line 10
def initialize(proj)
  if proj.kind_of? CoordinateReferenceSystem
    @crs = proj
  elsif proj.kind_of? GeoScript::Projection
    @crs = proj.crs
  elsif proj.kind_of? String
    @crs = CRS.decode proj
    
    if @crs.nil?
      @crs = CRS.parseWKT proj
      
      if @crs.nil?
        raise "Unable to determine projection from #{proj}"
      end
    end
  end
end
reproject(obj, from_crs, to_crs) click to toggle source
# File lib/geoscript/projection.rb, line 82
def self.reproject(obj, from_crs, to_crs)
  Projection.new(from_crs).transform obj, to_crs
end

Public Instance Methods

get_bounds() click to toggle source
# File lib/geoscript/projection.rb, line 36
def get_bounds
  env = CRS.get_envelope @crs
  if env
    min = env.get_minimum
    max = env.get_maximum
    GeoScript::Geom::Bounds.create min.first, min.last, max.first, max.last
  end
end
get_geobounds() click to toggle source
# File lib/geoscript/projection.rb, line 45
def get_geobounds
  box = CRS.get_geographic_bounding_box @crs
  if box
    GeoScript::Geom::Bounds.create box.west_bound_longitude, box.south_bound_latitude, box.east_bound_longitude, box.north_bound_latitude, 'epsg:4326'
  end
end
get_id() click to toggle source
# File lib/geoscript/projection.rb, line 28
def get_id
  CRS.lookup_identifier(@crs, true).to_s
end
get_wkt() click to toggle source
# File lib/geoscript/projection.rb, line 32
def get_wkt
  @crs.to_s
end
transform(obj, dest) click to toggle source
# File lib/geoscript/projection.rb, line 52
def transform(obj, dest)
  from_crs = @crs
  to_crs = Projection.new(dest).crs
  transform = CRS.find_math_transform(from_crs, to_crs)

  if obj.kind_of? Array
  else
    geometry_transform = GeometryCoordinateSequenceTransformer.new
    geometry_transform.math_transform = transform
    new_geom = geometry_transform.transform obj
    # not entirely comfortable with this
    case new_geom.class.to_s
    when 'Java::ComVividsolutionsJtsGeom::Point'
      GeoScript::Geom::Point.new new_geom
    when 'Java::ComVividsolutionsJtsGeom::Polygon'
      GeoScript::Geom::Polygon.new new_geom
    when 'Java::ComVividsolutionsJtsGeom::MultiPoint'
      GeoScript::Geom::MultiPoint.create new_geom
    when 'Java::ComVividsolutionsJtsGeom::MultiPolygon'
      GeoScript::Geom::MultiPolygon.create new_geom
    when 'Java::ComVividsolutionsJtsGeom::LineString'
      GeoScript::Geom::LineString.create new_geom
    when 'Java::ComVividsolutionsJtsGeom::MultiLineString'
      GeoScript::Geom::MultiLineString.create new_geom
    when 'Java::ComVividsolutionsJtsGeom::LinearRing'
      GeoScript::Geom::LinearRing.create new_geom
    end  
  end
end