point_datasource.cpp

// This class implements a simple way of displaying point-based data in Mapnik
// (It has yet to be tested as Mapnik r729's memory_featureset is commented out now.)
//
class point_datasource : public mapnik::memory_datasource {
public:
	point_datasource() : feat_id(0) {}
	void add_point(double x, double y, const char* key, const char* value);
	int type() const { return mapnik::datasource::Raster; }

private:
	int feat_id;
};

void point_datasource::add_point(double x, double y, 
				 const char* key, const char* value)
{
	using namespace mapnik;
	feature_ptr feature(feature_factory::create(feat_id++));
	geometry2d * pt = new point_impl;
	pt->move_to(x,y);
	feature->add_geometry(pt);
	transcoder tr("utf-8");
	(*feature)[key] = tr.transcode(value);
	this->push(feature);
}