// mapnik #include #include // boost #include "hello_featureset.hpp" hello_featureset::hello_featureset(mapnik::box2d const& box, std::string const& encoding) : box_(box), feature_id_(1), tr_(new mapnik::transcoder(encoding)), ctx_(std::make_shared()) { // add known field names to attributes schema ctx_->push("key"); } hello_featureset::~hello_featureset() { } mapnik::feature_ptr hello_featureset::next() { if (feature_id_ == 1) { // create a new feature mapnik::feature_ptr feature(mapnik::feature_factory::create(ctx_,feature_id_)); // increment the count ++feature_id_; // create an attribute pair of key:value feature->put("key",tr_->transcode("hello world point!")); // take the center of the bbox that was used to query // to dynamically generate a fake point mapnik::coord2d center = box_.center(); // create a new point geometry feature->set_geometry(mapnik::geometry::point(center.x,center.y)); // return the feature! return feature; } else if (feature_id_ == 2) { // create a second feature mapnik::feature_ptr feature(mapnik::feature_factory::create(ctx_,feature_id_)); // increment the count ++feature_id_; // create an attribute pair of key:value feature->put("key",tr_->transcode("hello world line!")); // take the outer ring of the bbox that was used to query // to dynamically generate a fake line mapnik::geometry::line_string line; line.reserve(4); line.add_coord(box_.minx(),box_.maxy()); line.add_coord(box_.maxx(),box_.maxy()); line.add_coord(box_.maxx(),box_.miny()); line.add_coord(box_.minx(),box_.miny()); feature->set_geometry(std::move(line)); return feature; } // otherwise return an empty feature return mapnik::feature_ptr(); }