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