diff options
Diffstat (limited to 'src/mbgl/style/expression/within.cpp')
| -rw-r--r-- | src/mbgl/style/expression/within.cpp | 58 |
1 files changed, 32 insertions, 26 deletions
diff --git a/src/mbgl/style/expression/within.cpp b/src/mbgl/style/expression/within.cpp index 1b1b8b11b9..d02ea47cb2 100644 --- a/src/mbgl/style/expression/within.cpp +++ b/src/mbgl/style/expression/within.cpp @@ -1,10 +1,13 @@ +#include <mbgl/style/expression/within.hpp> + #include <mapbox/geojson.hpp> #include <mapbox/geometry.hpp> #include <mbgl/style/conversion_impl.hpp> -#include <mbgl/style/expression/within.hpp> #include <mbgl/tile/geometry_tile_data.hpp> +#include <mbgl/util/logging.hpp> #include <mbgl/util/string.hpp> +namespace mbgl { namespace { double isLeft(mbgl::Point<double> P0, mbgl::Point<double> P1, mbgl::Point<double> P2) { @@ -13,14 +16,13 @@ double isLeft(mbgl::Point<double> P0, mbgl::Point<double> P1, mbgl::Point<double // winding number algorithm for checking if point inside a ploygon or not. // http://geomalgorithms.com/a03-_inclusion.html#wn_PnPoly() -bool pointWithinPoly(mbgl::Point<double> point, const mapbox::geometry::polygon<double>& polys) { +bool pointWithinPolygons(mbgl::Point<double> point, const mapbox::geometry::polygon<double>& polys) { // wn = the winding number (=0 only when point is outside) int wn = 0; for (auto poly : polys) { auto size = poly.size(); - auto i = size; // loop through every edge of the polygon - for (i = 0; i < size - 1; ++i) { + for (decltype(size) i = 0; i < size - 1; ++i) { if (poly[i].y <= point.y) { if (poly[i + 1].y > point.y) { // upward horizontal crossing from point to edge E(poly[i], poly[i+1]) if (isLeft(poly[i], poly[i + 1], point) > 0) { @@ -42,34 +44,33 @@ bool pointWithinPoly(mbgl::Point<double> point, const mapbox::geometry::polygon< return wn != 0; } -bool pointsWithinPoly(const mbgl::GeometryTileFeature& feature, - const mbgl::CanonicalTileID& canonical, - const mbgl::GeoJSON& geoJson) { - bool result = false; - geoJson.match( - [&](const mapbox::geometry::geometry<double>& geometrySet) { - geometrySet.match( - [&](const mapbox::geometry::polygon<double>& polygons) { - convertGeometry(feature, canonical) +bool pointsWithinPolygons(const mbgl::GeometryTileFeature& feature, + const mbgl::CanonicalTileID& canonical, + const mbgl::GeoJSON& geoJson) { + return geoJson.match( + [&feature, &canonical](const mapbox::geometry::geometry<double>& geometrySet) -> bool { + return geometrySet.match( + [&feature, &canonical](const mapbox::geometry::polygon<double>& polygons) -> bool { + return convertGeometry(feature, canonical) .match( - [&](const mapbox::geometry::point<double>& point) { - result = pointWithinPoly(point, polygons); + [&polygons](const mapbox::geometry::point<double>& point) -> bool { + return pointWithinPolygons(point, polygons); }, - [&](const mapbox::geometry::multi_point<double>& points) { + [&polygons](const mapbox::geometry::multi_point<double>& points) -> bool { + auto result = false; for (const auto& p : points) { - result = pointWithinPoly(p, polygons); + result = pointWithinPolygons(p, polygons); if (!result) { - return; + return result; } } + return result; }, - [&](const auto&) { return; }); + [](const auto&) -> bool { return false; }); }, - [&](const auto&) { return; }); + [](const auto&) -> bool { return false; }); }, - [&](const auto&) { return; }); - - return result; + [](const auto&) -> bool { return false; }); } mbgl::optional<mbgl::GeoJSON> parseValue(const mbgl::style::conversion::Convertible& value_, @@ -89,15 +90,18 @@ mbgl::optional<mbgl::GeoJSON> parseValue(const mbgl::style::conversion::Converti } } ctx.error("'Within' expression requires valid geojson source that contains polygon geometry type."); - return mbgl::optional<mbgl::GeoJSON>(); + return nullopt; } } // namespace -namespace mbgl { namespace style { namespace expression { +Within::Within(GeoJSON geojson) : Expression(Kind::Within, type::Boolean), geoJSONSource(std::move(geojson)) {} + +Within::~Within() {} + using namespace mbgl::style::conversion; EvaluationResult Within::evaluate(const EvaluationContext& params) const { @@ -107,7 +111,9 @@ EvaluationResult Within::evaluate(const EvaluationContext& params) const { auto geometryType = params.feature->getType(); // Currently only support Point/Points in polygon if (geometryType == FeatureType::Point) { - return pointsWithinPoly(*params.feature, *params.canonical, geoJSONSource); + return pointsWithinPolygons(*params.feature, *params.canonical, geoJSONSource); + } else { + mbgl::Log::Warning(mbgl::Event::General, "Within expression currently only support 'Point' geometry type"); } return false; } |