geovctrs_extcpp.R

Rcpp::sourceCpp(
  code = '
  #include "geovctrs/geos-operator.hpp"
  
  // [[Rcpp::depends(geovctrs)]]
  
  class BufferOp: public UnaryGeometryOperator {
    GEOSGeometry* operateNext(GEOSContextHandle_t context, GEOSGeometry* geometry, size_t i) {
      // width, segments per quandrant
      return GEOSBuffer_r(context, geometry, 2, 30);
    }
  };
    
  // [[Rcpp::export]]
  SEXP buffer2(SEXP data, SEXP ptype) {
    BufferOp op;
    op.initProvider(data);
    op.initExporter(ptype);
    return op.operate();
  }
  '
)

buffer2(geovctrs::geo_wkt("POINT (30 10)"), geovctrs::geo_wkt())