Packages
geo
3.3.0
4.1.0
4.0.1
4.0.0
3.6.0
3.5.1
3.5.0
3.4.3
3.4.2
3.4.1
3.4.0
3.3.8
3.3.7
3.3.5
3.3.4
3.3.3
3.3.2
3.3.1
3.3.0
3.2.0
3.1.0
3.0.0
2.1.0
2.0.0
1.5.0
1.4.1
1.4.0
1.3.1
1.3.0
1.2.1
1.2.0
1.1.2
1.1.1
1.1.0
1.0.6
1.0.5
1.0.4
1.0.3
1.0.2
1.0.1
1.0.0
0.18.0
0.17.0
0.16.1
0.16.0
0.15.2
0.15.1
0.15.0
0.14.0
0.13.0
0.12.0
0.11.2
0.11.1
0.11.0
0.10.1
0.10.0
0.9.3
0.9.2
0.9.1
0.9.0
0.8.0
0.7.2
0.7.1
0.6.1
0.5.1
Encodes and decodes WKB, WKT, and GeoJSON formats.
Current section
Files
Jump to
Current section
Files
lib/geo/wkt/encoder.ex
defmodule Geo.WKT.Encoder do
@moduledoc false
alias Geo.{
Point,
PointZ,
PointM,
PointZM,
LineString,
LineStringZ,
Polygon,
PolygonZ,
MultiPoint,
MultiPointZ,
MultiLineString,
MultiLineStringZ,
MultiPolygon,
MultiPolygonZ,
GeometryCollection
}
@doc """
Takes a Geometry and returns a WKT string
"""
@spec encode(Geo.geometry()) :: {:ok, binary} | {:error, Exception.t()}
def encode(geom) do
{:ok, encode!(geom)}
rescue
exception ->
{:error, exception}
end
@doc """
Takes a Geometry and returns a WKT string
"""
@spec encode!(Geo.geometry()) :: binary
def encode!(geom) do
get_srid_binary(geom.srid) <> do_encode(geom)
end
defp do_encode(%Point{coordinates: {x, y}}) do
"POINT(#{x} #{y})"
end
defp do_encode(%PointZ{coordinates: {x, y, z}}) do
"POINT Z(#{x} #{y} #{z})"
end
defp do_encode(%PointM{coordinates: {x, y, m}}) do
"POINT M(#{x} #{y} #{m})"
end
defp do_encode(%PointZM{coordinates: {x, y, z, m}}) do
"POINT ZM(#{x} #{y} #{z} #{m})"
end
defp do_encode(%LineString{coordinates: coordinates}) do
coordinate_string = create_line_string_str(coordinates)
"LINESTRING#{coordinate_string}"
end
defp do_encode(%LineStringZ{coordinates: coordinates}) do
coordinate_string = create_line_string_str(coordinates)
"LINESTRINGZ#{coordinate_string}"
end
defp do_encode(%Polygon{coordinates: coordinates}) do
coordinate_string = create_polygon_str(coordinates)
"POLYGON#{coordinate_string}"
end
defp do_encode(%PolygonZ{coordinates: coordinates}) do
coordinate_string = create_polygon_str(coordinates)
"POLYGON#{coordinate_string}"
end
defp do_encode(%MultiPoint{coordinates: coordinates}) do
coordinate_string = create_line_string_str(coordinates)
"MULTIPOINT#{coordinate_string}"
end
defp do_encode(%MultiPointZ{coordinates: coordinates}) do
coordinate_string = create_line_string_str(coordinates)
"MULTIPOINTZ#{coordinate_string}"
end
defp do_encode(%MultiLineString{coordinates: coordinates}) do
coordinate_string = create_polygon_str(coordinates)
"MULTILINESTRING#{coordinate_string}"
end
defp do_encode(%MultiLineStringZ{coordinates: coordinates}) do
coordinate_string = create_polygon_str(coordinates)
"MULTILINESTRINGZ#{coordinate_string}"
end
defp do_encode(%MultiPolygon{coordinates: coordinates}) do
coordinate_string = create_multi_polygon_str(coordinates)
"MULTIPOLYGON#{coordinate_string}"
end
defp do_encode(%MultiPolygonZ{coordinates: coordinates}) do
coordinate_string = create_multi_polygon_str(coordinates)
"MULTIPOLYGONZ#{coordinate_string}"
end
defp do_encode(%GeometryCollection{geometries: geometries}) do
geom_str = Enum.map(geometries, &do_encode(&1)) |> Enum.join(",")
"GEOMETRYCOLLECTION(#{geom_str})"
end
defp create_line_string_str(coordinates) do
coordinate_str =
coordinates
|> Enum.map(&create_coord_str(&1))
|> Enum.join(",")
"(#{coordinate_str})"
end
defp create_polygon_str(coordinates) do
coordinate_str =
coordinates
|> Enum.map(&create_line_string_str(&1))
|> Enum.join(",")
"(#{coordinate_str})"
end
defp create_multi_polygon_str(coordinates) do
coordinate_str =
coordinates
|> Enum.map(&create_polygon_str(&1))
|> Enum.join(",")
"(#{coordinate_str})"
end
defp create_coord_str({x, y}), do: "#{x} #{y}"
defp create_coord_str({x, y, z}), do: "#{x} #{y} #{z}"
defp get_srid_binary(nil), do: ""
defp get_srid_binary(0), do: ""
defp get_srid_binary(srid), do: "SRID=#{srid};"
end