featureset_ptr shape_datasource::features(const query& q) const
{
filter_in_box filter(q.get_bbox());
if (indexed_)
{
return featureset_ptr(new shape_index_featureset<filter_in_box>(filter,shape_name_,q.property_names()));
}
return featureset_ptr(new shape_featureset<filter_in_box>(filter,shape_name_,q.property_names(),file_length_));
}
featureset_ptr memory_datasource::features_at_point(coord2d const& pt) const
{
box2d<double> box = box2d<double>(pt.x, pt.y, pt.x, pt.y);
#ifdef MAPNIK_DEBUG
std::clog << "box=" << box << ", pt x=" << pt.x << ", y=" << pt.y << "\n";
#endif
return featureset_ptr(new memory_featureset(box,*this));
}
featureset_ptr Map::query_point(unsigned index, double x, double y) const
{
if (!current_extent_.valid())
{
throw std::runtime_error("query_point: map extent is not intialized, you need to set a valid extent before querying");
}
if (!current_extent_.intersects(x,y))
{
throw std::runtime_error("query_point: x,y coords do not intersect map extent");
}
if (index < layers_.size())
{
mapnik::layer const& layer = layers_[index];
mapnik::datasource_ptr ds = layer.datasource();
if (ds)
{
mapnik::projection dest(srs_);
mapnik::projection source(layer.srs());
proj_transform prj_trans(source,dest);
double z = 0;
if (!prj_trans.equal() && !prj_trans.backward(x,y,z))
{
throw std::runtime_error("query_point: could not project x,y into layer srs");
}
// calculate default tolerance
mapnik::box2d<double> map_ex = current_extent_;
if (maximum_extent_)
{
map_ex.clip(*maximum_extent_);
}
if (!prj_trans.backward(map_ex,PROJ_ENVELOPE_POINTS))
{
std::ostringstream s;
s << "query_point: could not project map extent '" << map_ex
<< "' into layer srs for tolerance calculation";
throw std::runtime_error(s.str());
}
double tol = (map_ex.maxx() - map_ex.minx()) / width_ * 3;
featureset_ptr fs = ds->features_at_point(mapnik::coord2d(x,y), tol);
MAPNIK_LOG_DEBUG(map) << "map: Query at point tol=" << tol << "(" << x << "," << y << ")";
if (fs)
{
return boost::make_shared<filter_featureset<hit_test_filter> >(fs,
hit_test_filter(x,y,tol));
}
}
}
else
{
std::ostringstream s;
s << "Invalid layer index passed to query_point: '" << index << "'";
if (!layers_.empty()) s << " for map with " << layers_.size() << " layers(s)";
else s << " (map has no layers)";
throw std::out_of_range(s.str());
}
return featureset_ptr();
}
featureset_ptr Map::query_map_point(unsigned index, double x, double y) const
{
if ( index< layers_.size())
{
mapnik::layer const& layer = layers_[index];
CoordTransform tr = view_transform();
tr.backward(&x,&y);
try
{
mapnik::projection dest(srs_);
mapnik::projection source(layer.srs());
proj_transform prj_trans(source,dest);
double z = 0;
prj_trans.backward(x,y,z);
double minx = current_extent_.minx();
double miny = current_extent_.miny();
double maxx = current_extent_.maxx();
double maxy = current_extent_.maxy();
prj_trans.backward(minx,miny,z);
prj_trans.backward(maxx,maxy,z);
double tol = (maxx - minx) / width_ * 3;
mapnik::datasource_ptr ds = layer.datasource();
if (ds)
{
#ifdef MAPNIK_DEBUG
std::clog << " query at point tol = " << tol << " (" << x << "," << y << ")\n";
#endif
featureset_ptr fs = ds->features_at_point(mapnik::coord2d(x,y));
if (fs)
return featureset_ptr(new filter_featureset<hit_test_filter>(fs,hit_test_filter(x,y,tol)));
}
}
catch (...)
{
#ifdef MAPNIK_DEBUG
std::clog << "exception caught in \"query_map_point\"\n";
#endif
}
}
return featureset_ptr();
}
featureset_ptr memory_datasource::features(const query& q) const
{
return featureset_ptr(new memory_featureset(q.get_bbox(),*this));
}