Open-Harbor/osrm-backend
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases 3 Wiki Activity

Port osmium point-in-polygon function

Browse Source
This commit is contained in:
Michael Krasnyk 2017-08-30 16:33:23 +02:00
parent b15288e0ea
commit 421115200b
3 changed files with 175 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
include/extractor/location_dependent_data.hpp
View File

@ -3,6 +3,7 @@
#include <boost/filesystem/path.hpp>
#include <boost/geometry.hpp>
#include <boost/geometry/geometries/point_xy.hpp>
#include <boost/geometry/index/rtree.hpp>
#include <osmium/osm/way.hpp>
@ -14,11 +15,14 @@ namespace osrm
{
namespace extractor
{
struct LocationDependentData
{
using point_t = boost::geometry::model::
point<double, 2, boost::geometry::cs::spherical_equatorial<boost::geometry::degree>>;
using point_t = boost::geometry::model::d2::
point_xy<double, boost::geometry::cs::spherical_equatorial<boost::geometry::degree>>;
using segment_t = std::pair<point_t, point_t>;
using polygon_t = boost::geometry::model::polygon<point_t>;
using polygon_bands_t = std::vector<std::vector<segment_t>>;
using box_t = boost::geometry::model::box<point_t>;
using polygon_position_t = std::size_t;
@ -42,7 +46,7 @@ struct LocationDependentData
void loadLocationDependentData(const boost::filesystem::path &file_path);
rtree_t rtree;
std::vector<std::pair<polygon_t, std::size_t>> polygons;
std::vector<std::pair<polygon_bands_t, std::size_t>> polygons;
std::vector<properties_t> properties;
};
}

112
src/extractor/location_dependent_data.cpp
View File

@ -9,6 +9,7 @@
#include <boost/filesystem.hpp>
#include <boost/function_output_iterator.hpp>
#include <boost/geometry/algorithms/equals.hpp>
#include <fstream>
#include <string>
@ -109,7 +110,62 @@ void LocationDependentData::loadLocationDependentData(const boost::filesystem::p
}
auto envelop = boost::geometry::return_envelope<box_t>(polygon);
bounding_boxes.emplace_back(envelop, polygons.size());
polygons.emplace_back(std::make_pair(polygon, properties_index));
// here is a part of ExtractPolygon::ExtractPolygon code
// TODO: remove copy overhead
constexpr const int32_t segments_per_band = 10;
constexpr const int32_t max_bands = 10000;
const auto y_min = envelop.min_corner().y();
const auto y_max = envelop.max_corner().y();
std::vector<segment_t> segments;
auto add_ring = [&segments](const auto &ring) {
auto it = ring.begin();
const auto end = ring.end();
BOOST_ASSERT(it != end);
auto last_it = it++;
while (it != end)
{
segments.emplace_back(*last_it, *it);
last_it = it++;
}
};
add_ring(polygon.outer());
for (const auto &ring : polygon.inners())
add_ring(ring);
int32_t num_bands = static_cast<int32_t>(segments.size()) / segments_per_band;
if (num_bands < 1)
{
num_bands = 1;
}
else if (num_bands > max_bands)
{
num_bands = max_bands;
}
polygon_bands_t bands(num_bands);
const auto dy = (y_max - y_min) / num_bands;
for (const auto &segment : segments)
{
using coord_t = boost::geometry::traits::coordinate_type<point_t>::type;
const std::pair<coord_t, coord_t> mm =
std::minmax(segment.first.y(), segment.second.y());
const auto band_min = std::min<coord_t>(num_bands - 1, (mm.first - y_min) / dy);
const auto band_max = std::min<coord_t>(
num_bands, ((mm.second - y_min) / dy) + 1); // TODO: use integer coordinates
for (auto band = band_min; band < band_max; ++band)
{
bands[band].push_back(segment);
}
}
// EOC
polygons.emplace_back(std::make_pair(bands, properties_index));
};
for (rapidjson::SizeType ifeature = 0; ifeature < features_array.Size(); ifeature++)
@ -156,7 +212,59 @@ LocationDependentData::properties_t LocationDependentData::operator()(const poin
// Search the R-tree and collect a Lua table of tags that correspond to the location
rtree.query(boost::geometry::index::intersects(point) &&
boost::geometry::index::satisfies([this, &point](const rtree_t::value_type &v) {
return boost::geometry::within(point, polygons[v.second].first);
// Simple point-in-polygon algorithm adapted from
// https://www.ecse.rpi.edu/Homepages/wrf/Research/Short_Notes/pnpoly.html
const auto &envelop = v.first;
const auto &bands = polygons[v.second].first;
const auto y_min = envelop.min_corner().y();
const auto y_max = envelop.max_corner().y();
auto dy = (y_max - y_min) / bands.size();
std::size_t band = (point.y() - y_min) / dy;
if (band >= bands.size())
{
band = bands.size() - 1;
}
bool inside = false;
for (const auto &segment : bands[band])
{
const auto point_x = point.x(), point_y = point.y();
const auto from_x = segment.first.x(), from_y = segment.first.y();
const auto to_x = segment.second.x(), to_y = segment.second.y();
if (to_y == from_y)
{ // handle horizontal segments: check if on boundary or skip
if ((to_y == point_y) &&
(from_x == point_x || (to_x > point_x) != (from_x > point_x)))
return true;
continue;
}
if ((to_y > point_y) != (from_y > point_y))
{
const auto ax = to_x - from_x;
const auto ay = to_y - from_y;
const auto tx = point_x - from_x;
const auto ty = point_y - from_y;
const auto cross_product = tx * ay - ax * ty;
if (cross_product == 0)
return true;
if ((ay > 0) == (cross_product > 0))
{
inside = !inside;
}
}
}
return inside;
}),
boost::make_function_output_iterator(std::ref(merger)));

68
unit_tests/extractor/location_dependent_data_tests.cpp
View File

@ -51,10 +51,10 @@ BOOST_AUTO_TEST_CASE(polygon_tests)
LocationDependentData data(fixture.temporary_file);
BOOST_CHECK(data(point_t(0, 0)).empty());
BOOST_CHECK(data(point_t(1, 1)).empty());
BOOST_CHECK(data(point_t(0, 1)).empty());
BOOST_CHECK(data(point_t(0.5, -0.5)).empty());
BOOST_CHECK(data(point_t(0, -3)).empty());
BOOST_CHECK(!data(point_t(1, 1)).empty());
BOOST_CHECK(!data(point_t(0, 1)).empty());
BOOST_CHECK(!data(point_t(0.5, -0.5)).empty());
BOOST_CHECK(!data(point_t(0, -3)).empty());
BOOST_CHECK(!data(point_t(-0.75, 0.75)).empty());
BOOST_CHECK(!data(point_t(-2, 6)).empty());
BOOST_CHECK_EQUAL(boost::get<double>(data(point_t(2, 0))["answer"]), 42.);
@ -110,13 +110,61 @@ BOOST_AUTO_TEST_CASE(polygon_merging_tests)
]})json");
LocationDependentData data(fixture.temporary_file);
BOOST_CHECK_EQUAL(boost::get<std::string>(data(point_t(0, 0))["answer"]), "a");
BOOST_CHECK_EQUAL(boost::get<std::string>(data(point_t(-3, 3))["answer"]), "a");
BOOST_CHECK_EQUAL(boost::get<std::string>(data(point_t(-3, 1))["answer"]), "a");
BOOST_CHECK_EQUAL(boost::get<std::string>(data(point_t(-3, -3))["answer"]), "a");
BOOST_CHECK_EQUAL(boost::get<std::string>(data(point_t(0, 3))["answer"]), "a");
BOOST_CHECK_EQUAL(boost::get<std::string>(data(point_t(1, 0))["answer"]), "a");
BOOST_CHECK_EQUAL(boost::get<std::string>(data(point_t(2, 0))["answer"]), "a");
BOOST_CHECK_EQUAL(boost::get<std::string>(data(point_t(3, 0))["answer"]), "b");
BOOST_CHECK_EQUAL(boost::get<std::string>(data(point_t(4, 0))["answer"]), "b");
BOOST_CHECK_EQUAL(boost::get<std::string>(data(point_t(6, 0))["answer"]), "b");
BOOST_CHECK_EQUAL(boost::get<std::string>(data(point_t(7, 0))["answer"]), "c");
BOOST_CHECK_EQUAL(boost::get<std::string>(data(point_t(2, -3))["answer"]), "a");
BOOST_CHECK_EQUAL(boost::get<std::string>(data(point_t(3, 0))["answer"]), "a");
BOOST_CHECK_EQUAL(boost::get<std::string>(data(point_t(4, 3))["answer"]), "b");
BOOST_CHECK_EQUAL(boost::get<std::string>(data(point_t(6, 1))["answer"]), "b");
BOOST_CHECK_EQUAL(boost::get<std::string>(data(point_t(7, 0))["answer"]), "b");
BOOST_CHECK_EQUAL(boost::get<std::string>(data(point_t(8, 3))["answer"]), "c");
BOOST_CHECK_EQUAL(boost::get<std::string>(data(point_t(8, -1))["answer"]), "c");
BOOST_CHECK_EQUAL(boost::get<std::string>(data(point_t(8, -3))["answer"]), "c");
}
BOOST_AUTO_TEST_CASE(staircase_polygon)
{
LocationDataFixture fixture(R"json({
"type": "FeatureCollection",
"features": [
{
"type": "Feature",
"properties": { "answer": "a" },
"geometry": { "type": "Polygon", "coordinates": [ [ [0, 0], [3, 0], [3, 3], [2, 3], [2, 2], [1, 2], [1, 1], [0, 1], [0, 0] ] ] }
}
]})json");
LocationDependentData data(fixture.temporary_file);
// all corners
BOOST_CHECK(!data(point_t(0, 0)).empty());
BOOST_CHECK(!data(point_t(0, 1)).empty());
BOOST_CHECK(!data(point_t(1, 1)).empty());
BOOST_CHECK(!data(point_t(1, 2)).empty());
BOOST_CHECK(!data(point_t(2, 2)).empty());
BOOST_CHECK(!data(point_t(2, 3)).empty());
BOOST_CHECK(!data(point_t(3, 3)).empty());
BOOST_CHECK(!data(point_t(3, 0)).empty());
// at x = 1
BOOST_CHECK(data(point_t(1, -0.5)).empty());
BOOST_CHECK(!data(point_t(1, 0)).empty());
BOOST_CHECK(!data(point_t(1, 0.5)).empty());
BOOST_CHECK(!data(point_t(1, 1.5)).empty());
BOOST_CHECK(data(point_t(1, 2.5)).empty());
BOOST_CHECK(data(point_t(3.5, 2)).empty());
// at y = 2
BOOST_CHECK(data(point_t(0.5, 2)).empty());
BOOST_CHECK(!data(point_t(1, 2)).empty());
BOOST_CHECK(!data(point_t(1.5, 2)).empty());
BOOST_CHECK(!data(point_t(2, 2)).empty());
BOOST_CHECK(!data(point_t(2.5, 2)).empty());
BOOST_CHECK(!data(point_t(3, 2)).empty());
BOOST_CHECK(data(point_t(3.5, 2)).empty());
}
BOOST_AUTO_TEST_SUITE_END()