Geojson

DESCRIPTION

@@ -1,7 +1,7 @@
 Package: geojsonsf
 Type: Package
 Title: GeoJSON to Simple Feature Converter
-Version: 0.3.0003
+Version: 0.3.0004
 Authors@R: c(
     person("David", "Cooley", ,"[email protected]", role = c("aut", "cre"))
     )

NAMESPACE

@@ -6,8 +6,12 @@ S3method(geojson_sf,default)
 S3method(geojson_sfc,character)
 S3method(geojson_sfc,connection)
 S3method(geojson_sfc,default)
+S3method(sf_geojson,sf)
+S3method(sf_geojson,sfc)
+S3method(sf_geojson,sfg)
 export(geojson_sf)
 export(geojson_sfc)
 export(geojson_wkt)
+export(sf_geojson)
 importFrom(Rcpp,sourceCpp)
 useDynLib(geojsonsf, .registration = TRUE)

R/RcppExports.R

@@ -21,3 +21,7 @@ rcpp_read_sf_file <- function(file) {
     .Call(`_geojsonsf_rcpp_read_sf_file`, file)
 }
 
+rcpp_sf_to_geojson <- function(sf, atomise) {
+    .Call(`_geojsonsf_rcpp_sf_to_geojson`, sf, atomise)
+}
+

R/geojson_sf.R

@@ -88,6 +88,36 @@ geojson_sf.connection <- function(geojson) geojson_sf(read_url(geojson))
 #' @export
 geojson_sf.default <- function(geojson) rcpp_geojson_to_sf(geojson)
 
+
+## TODO:
+## - atomise - logical?
+## -- Return a JSON array of objects
+## -- Return an R Vector of objects?
+
+#' sf to GeoJSON
+#'
+#' Converts `sf`, `sfc` and `sfg` objects to GeoJSON
+#'
+#' @param sf simple feature object
+#' @param atomise logical
+#'
+#' @export
+sf_geojson <- function(sf, atomise = FALSE) UseMethod("sf_geojson")
+
+#' @export
+sf_geojson.sf <- function(sf, atomise) rcpp_sf_to_geojson(sf, atomise)
+
+#' @export
+sf_geojson.sfc <- function(sf, atomise) rcpp_sf_to_geojson(sf, atomise)
+
+#' @export
+sf_geojson.sfg <- function(sf, atomise) rcpp_sf_to_geojson(sf, atomise)
+
+sf_geojson.default <- function(sf, atomise) stop("Expected an sf object")
+
+
+
+
 is_url <- function(geojson) grepl("^https?://", geojson, useBytes=TRUE)
 
 read_url <- function(con) {

R/scratch.R

@@ -0,0 +1,129 @@
+## sf to GeoJSON
+
+## stream the data.frame, row by row.
+##
+
+# js <- '{"type" : "Point", "coordinates" : [0, 0]}'
+# sf <- geojson_sf(js)
+# sf
+# sf_geojson(sf)
+#
+# js <- '{"type" : "MultiPoint", "coordinates" : [ [0, 0], [1, 1] ]}'
+# sf <- geojson_sf(js)
+# sf
+# sf_geojson(sf)
+#
+# js <- '{"type" : "MultiLineString", "coordinates" : [ [ [0, 0], [1, 1] ] ]}'
+# sf <- geojson_sf(js)
+# sf
+# sf_geojson(sf)
+#
+# js <- '{"type" : "Polygon", "coordinates" : [ [ [0, 0], [1, 1] ] ]}'
+# sf <- geojson_sf(js)
+# sf
+# sf_geojson(sf)
+#
+# js <- '[{"type" : "Polygon", "coordinates" : [ [ [0, 0], [1, 1] ] ]},
+# {"type" : "MultiLineString", "coordinates" : [ [ [0, 0], [1, 1] ], [[3,3],[4,4]] ]}]'
+# sf <- geojson_sf(js)
+# sf
+# sf_geojson(sf)
+
+# js <- '{
+#   "type": "GeometryCollection", "geometries": [
+#     {"type": "Point", "coordinates": [100.0, 0.0]},
+#     {"type": "LineString", "coordinates": [[101.0, 0.0], [102.0, 1.0]]},
+#     {"type" : "MultiPoint", "coordinates" : [[0,0], [1,1], [2,2]]}
+#   ]}'
+# sf <- geojson_sf(js)
+# j <- sf_geojson(sf)
+#
+# j
+# gsub(" |\\n|\\r","",js)
+
+
+# js <- '[{"type" : "Polygon", "coordinates" : [ [ [0, 0], [1, 1] ] ]},
+# {"type" : "MultiLineString", "coordinates" : [ [ [0, 0], [1, 1] ] ]},
+# {
+#   "type": "GeometryCollection", "geometries": [
+#     {"type": "Point", "coordinates": [100.0, 0.0]},
+#     {"type": "LineString", "coordinates": [[101.0, 0.0], [102.0, 1.0]]},
+#     {"type" : "MultiPoint", "coordinates" : [[0,0], [1,1], [2,2]]}
+#   ]}
+# ]'
+# sf <- geojson_sf(js)
+# sf
+# sf_geojson(sf)
+
+# js <- '[
+# {
+#   "type": "Feature",
+#   "properties" : {},
+#   "geometry": {
+#   "type": "Polygon",
+#   "coordinates": [[
+# 	  [-10.0, -10.0],
+#   	[10.0, -10.0],
+#   	[10.0, 10.0],
+#   	[-10.0, -10.0]]]
+#   }
+# },
+# {
+# 	"type": "Feature",
+# 	"properties" : { "id" : 1, "foo" : false, "bar" : "world" },
+# 	"geometry": {
+# 	"type": "MultiPolygon",
+# 	"coordinates": [
+# 	[[[180.0, 40.0], [180.0, 50.0], [170.0, 50.0],
+# 	[170.0, 40.0], [180.0, 40.0]]],
+# 	[[[-170.0, 40.0], [-170.0, 50.0], [-180.0, 50.0],
+# 	[-180.0, 40.0], [-170.0, 40.0]]]]
+# 	}
+# }
+# ]'
+# sf <- geojson_sf(js)
+# sf_geojson(sf)
+# geojson_sf( sf_geojson(sf) )
+
+
+
+# js <- '{"type":"MultiPolygon","coordinates":[[[[0,0],[0,1],[1,1],[1,0],[0,0]]]]}'
+# sf_geojson(geojson_sf(js))
+
+# js <- '{
+#   "type":"MultiLineString",
+#   "coordinates":[
+#     [
+#       [0,0],[0,1],[1,1],[1,0],[0,0]
+#     ],
+#     [
+#       [2,2],[2,3],[3,3],[3,2],[2,2]
+#     ]
+#   ]
+# }'
+#
+# sf_geojson(geojson_sf(js))
+
+
+# js <- '{
+#   "type":"MultiPolygon",
+#   "coordinates":[
+#     [
+#       [
+#         [0,0],[0,1],[1,1],[1,0],[0,0]
+#       ],
+#       [
+#         [0.5,0.5],[0.5,0.75],[0.75,0.75],[0.75,0.5],[0.5,0.5]
+#       ]
+#     ],
+#     [
+#       [
+#         [2,2],[2,3],[3,3],[3,2],[2,2]
+#       ]
+#     ]
+#   ]
+# }'
+#
+# sf_geojson(geojson_sf(js), TRUE)
+
+

inst/include/geojson_wkt.h

@@ -3,18 +3,21 @@
 #define GEOJSON_WKT_H
 
 #include "rapidjson/document.h"
+using namespace rapidjson;
 
-void coordSeparateWKT(std::ostringstream& os, int i, int n);
+void coord_separator(std::ostringstream& os, int i, int n);
 
-void lineSeparateWKT(std::ostringstream& os, int i, int n);
+void line_separator_wkt(std::ostringstream& os, int i, int n);
 
-void polygonSeparateWKT(std::ostringstream& os, int i, int n);
+void object_separator(std::ostringstream& os);
 
-void addLonLatToWKTStream(std::ostringstream& os, float lon, float lat );
+void polygon_separate_wkt(std::ostringstream& os, int i, int n);
 
-void beginWKT(std::ostringstream& os, std::string& geom_type);
+void add_lonlat_to_wkt_stream(std::ostringstream& os, float lon, float lat );
 
-void endWKT(std::ostringstream& os, std::string& geom_type);
+void begin_wkt(std::ostringstream& os, std::string& geom_type);
+
+void end_wkt(std::ostringstream& os, std::string& geom_type);
 
 void point_to_wkt(std::ostringstream& os, const Value& coord_array);
 

inst/include/sf_geojson.h

@@ -0,0 +1,30 @@
+#ifndef SFGEOJSON_H
+#define SFGEOJSON_H
+
+#include <Rcpp.h>
+using namespace Rcpp;
+
+
+//void add_geometrycollection_to_stream(std::ostringstream& os, Rcpp::List& gc);
+
+void begin_geojson_geometry(Rcpp::String& geojson, std::string& geom_type);
+
+void begin_geojson_geometry(Rcpp::String& geojson, Rcpp::List& sfc, std::string& geom_type);
+
+void end_geojson_geometry(Rcpp::String& geojson, std::string& geom_type);
+
+void add_lonlat_to_stream(Rcpp::String& geojson, Rcpp::NumericVector& points);
+
+void fetch_coordinates(Rcpp::String& geojson, Rcpp::List& sfc, int& object_counter);
+
+void coord_separator(Rcpp::String& geojson, int i, int n);
+
+void line_separator_geojson(Rcpp::String& geojson, int i, int n);
+
+void polygon_separator_geojson(Rcpp::String& geojson, int i, int n);
+
+void write_geometry(Rcpp::List& sfg, Rcpp::String& geojson);
+
+void make_gc_type(Rcpp::String& geojson, Rcpp::List& sfg, std::string& geom_type, Rcpp::CharacterVector& cls);
+
+#endif

src/RcppExports.cpp

@@ -61,13 +61,26 @@ BEGIN_RCPP
     return rcpp_result_gen;
 END_RCPP
 }
+// rcpp_sf_to_geojson
+Rcpp::StringVector rcpp_sf_to_geojson(Rcpp::List sf, bool atomise);
+RcppExport SEXP _geojsonsf_rcpp_sf_to_geojson(SEXP sfSEXP, SEXP atomiseSEXP) {
+BEGIN_RCPP
+    Rcpp::RObject rcpp_result_gen;
+    Rcpp::RNGScope rcpp_rngScope_gen;
+    Rcpp::traits::input_parameter< Rcpp::List >::type sf(sfSEXP);
+    Rcpp::traits::input_parameter< bool >::type atomise(atomiseSEXP);
+    rcpp_result_gen = Rcpp::wrap(rcpp_sf_to_geojson(sf, atomise));
+    return rcpp_result_gen;
+END_RCPP
+}
 
 static const R_CallMethodDef CallEntries[] = {
     {"_geojsonsf_rcpp_geojson_to_sfc", (DL_FUNC) &_geojsonsf_rcpp_geojson_to_sfc, 1},
     {"_geojsonsf_rcpp_geojson_to_sf", (DL_FUNC) &_geojsonsf_rcpp_geojson_to_sf, 1},
     {"_geojsonsf_rcpp_geojson_to_wkt", (DL_FUNC) &_geojsonsf_rcpp_geojson_to_wkt, 1},
     {"_geojsonsf_rcpp_read_sfc_file", (DL_FUNC) &_geojsonsf_rcpp_read_sfc_file, 1},
     {"_geojsonsf_rcpp_read_sf_file", (DL_FUNC) &_geojsonsf_rcpp_read_sf_file, 1},
+    {"_geojsonsf_rcpp_sf_to_geojson", (DL_FUNC) &_geojsonsf_rcpp_sf_to_geojson, 2},
     {NULL, NULL, 0}
 };
 

src/geojson_to_wkt.cpp

@@ -26,9 +26,10 @@ void parse_geometry_object_wkt(Rcpp::List& sfc,
   const Value& coord_array = geometry["coordinates"];
   geometry_types.insert(geom_type);
 
-  std::ostringstream os;
-  Rcpp::StringVector wkt;
-  beginWKT(os, geom_type);
+	std::ostringstream os;
+	Rcpp::StringVector wkt;
+	begin_wkt(os, geom_type);
+
 
   if (geom_type == "Point") {
     point_to_wkt(os, coord_array);
@@ -52,7 +53,7 @@ void parse_geometry_object_wkt(Rcpp::List& sfc,
     Rcpp::stop("unknown sfg type");
   }
 
-  endWKT(os, geom_type);
+	end_wkt(os, geom_type);
 
   wkt = os.str();
   transform(geom_type.begin(), geom_type.end(), geom_type.begin(), ::toupper);
@@ -65,6 +66,7 @@ void parse_geometry_object_wkt(Rcpp::List& sfc,
 Rcpp::List parse_geometry_collection_object_wkt(const Value& val,
                                             std::set< std::string >& geometry_types,
                                             int& wkt_objects) {
+
   std::string geom_type;
 
   validate_geometries(val, wkt_objects);
@@ -88,7 +90,7 @@ Rcpp::List parse_geometry_collection_object_wkt(const Value& val,
   for (i = 0; i < n; i++) {
     std::string g = geom_collection[i];
     os << g;
-    coordSeparateWKT(os, i, n);
+    coord_separator(os, i, n);
   }
   os << ")";