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Diffstat (limited to 'src/mbgl/style/expression/distance.cpp')
| -rw-r--r-- | src/mbgl/style/expression/distance.cpp | 601 |
1 files changed, 601 insertions, 0 deletions
diff --git a/src/mbgl/style/expression/distance.cpp b/src/mbgl/style/expression/distance.cpp new file mode 100644 index 0000000000..67a460b7d7 --- /dev/null +++ b/src/mbgl/style/expression/distance.cpp @@ -0,0 +1,601 @@ +#include <mbgl/style/expression/distance.hpp> + +#include <mapbox/cheap_ruler.hpp> +#include <mapbox/geojson.hpp> +#include <mapbox/geometry.hpp> + +#include <mbgl/style/conversion/json.hpp> +#include <mbgl/tile/geometry_tile_data.hpp> +#include <mbgl/util/geometry_util.hpp> +#include <mbgl/util/logging.hpp> +#include <mbgl/util/string.hpp> + +#include <rapidjson/document.h> + +#include <algorithm> +#include <deque> +#include <limits> +#include <queue> +#include <tuple> + +namespace mbgl { +namespace { + +const std::size_t MinPointsSize = 500; +const std::size_t MinLinePointsSize = 200; + +using BBox = std::array<double, 4>; +const BBox DefaultBBox = BBox{std::numeric_limits<double>::infinity(), + std::numeric_limits<double>::infinity(), + -std::numeric_limits<double>::infinity(), + -std::numeric_limits<double>::infinity()}; + +// bbox[minX, minY, maxX, maxY] +void updateBBox(BBox& bbox, const mapbox::geometry::point<double>& p) { + bbox[0] = std::min(p.x, bbox[0]); + bbox[1] = std::min(p.y, bbox[1]); + bbox[2] = std::max(p.x, bbox[2]); + bbox[3] = std::max(p.y, bbox[3]); +} + +// Inclusive index range for multipoint or linestring container +using IndexRange = std::pair<std::size_t, std::size_t>; + +std::size_t getRangeSize(const IndexRange& range) { + return range.second - range.first + 1; +} + +BBox getBBox(const mapbox::geometry::multi_point<double>& points, const IndexRange& range) { + BBox bbox = DefaultBBox; + for (std::size_t i = range.first; i <= range.second; ++i) { + updateBBox(bbox, points[i]); + } + return bbox; +} + +BBox getBBox(const mapbox::geometry::line_string<double>& line, const IndexRange& range) { + BBox bbox = DefaultBBox; + for (std::size_t i = range.first; i <= range.second; ++i) { + updateBBox(bbox, line[i]); + } + return bbox; +} + +// Calculate the distance between two bounding boxes. +// Calculate the delta in x and y direction, and use two fake points {0, 0} and {dx, dy} to calculate the distance. +// Distance will be 0 if bounding box are overlapping. +double bboxToBBoxDistance(const BBox& bbox1, const BBox& bbox2, mapbox::cheap_ruler::CheapRuler& ruler) { + double dx = 0.; + double dy = 0.; + // bbox1 in left side + if (bbox1[2] < bbox2[0]) { + dx = bbox2[0] - bbox1[2]; + } + // bbox1 in right side + if (bbox1[0] > bbox2[2]) { + dx = bbox1[0] - bbox2[2]; + } + // bbox1 in above side + if (bbox1[1] > bbox2[3]) { + dy = bbox1[1] - bbox2[3]; + } + // bbox1 in down side + if (bbox1[3] < bbox2[1]) { + dy = bbox2[1] - bbox1[3]; + } + return ruler.distance(mapbox::geometry::point<double>{0., 0.}, mapbox::geometry::point<double>{dx, dy}); +} + +double pointToLineDistance(const mapbox::geometry::point<double>& point, + const mapbox::geometry::line_string<double>& line, + mapbox::cheap_ruler::CheapRuler& ruler) { + const auto nearestPoint = std::get<0>(ruler.pointOnLine(line, point)); + return ruler.distance(point, nearestPoint); +} + +double lineToLineDistance(const mapbox::geometry::line_string<double>& line1, + IndexRange& range1, + const mapbox::geometry::line_string<double>& line2, + IndexRange& range2, + mapbox::cheap_ruler::CheapRuler& ruler) { + double dist = std::numeric_limits<double>::infinity(); + for (std::size_t i = range1.first; i < range1.second; ++i) { + const auto& p1 = line1[i]; + const auto& p2 = line1[i + 1]; + for (std::size_t j = range2.first; j < range2.second; ++j) { + const auto& q1 = line2[j]; + const auto& q2 = line2[j + 1]; + if (GeometryUtil<double>::segmentIntersectSegment(p1, p2, q1, q2)) return 0.; + auto dist1 = std::min(pointToLineDistance(p1, mapbox::geometry::line_string<double>{q1, q2}, ruler), + pointToLineDistance(p2, mapbox::geometry::line_string<double>{q1, q2}, ruler)); + auto dist2 = std::min(pointToLineDistance(q1, mapbox::geometry::line_string<double>{p1, p2}, ruler), + pointToLineDistance(q2, mapbox::geometry::line_string<double>{p1, p2}, ruler)); + dist = std::min(dist, std::min(dist1, dist2)); + } + } + return dist; +} + +double pointsToPointsDistance(const mapbox::geometry::multi_point<double>& points1, + IndexRange& range1, + const mapbox::geometry::multi_point<double>& points2, + IndexRange& range2, + mapbox::cheap_ruler::CheapRuler& ruler) { + double dist = std::numeric_limits<double>::infinity(); + for (std::size_t i = range1.first; i <= range1.second; ++i) { + for (std::size_t j = range2.first; j <= range2.second; ++j) { + dist = std::min(dist, ruler.distance(points1[i], points2[j])); + if (dist == 0.) return dist; + } + } + return dist; +} + +std::pair<mbgl::optional<IndexRange>, mbgl::optional<IndexRange>> splitRange(const IndexRange& range, bool isLine) { + auto size = getRangeSize(range); + if (isLine) { + if (size == 2) { + return std::make_pair(range, nullopt); + } + auto size1 = size / 2; + IndexRange range1(range.first, range.first + size1); + IndexRange range2(range.first + size1, range.second); + return std::make_pair(std::move(range1), std::move(range2)); + } else { + if (size == 1) { + return std::make_pair(range, nullopt); + } + auto size1 = size / 2 - 1; + IndexRange range1(range.first, range.first + size1); + IndexRange range2(range.first + size1 + 1, range.second); + return std::make_pair(std::move(range1), std::move(range2)); + } +} + +// <distance, range1, range2> +using DistPair = std::tuple<double, IndexRange, IndexRange>; +class Comparator { +public: + bool operator()(DistPair& left, DistPair& right) { return std::get<0>(left) < std::get<0>(right); } +}; +// The priority queue will ensure the top element would always be the pair that has the biggest distance +using DistQueue = std::priority_queue<DistPair, std::deque<DistPair>, Comparator>; + +// Divide and conqure, the time complexity is O(n*lgn), faster than Brute force O(n*n) +// Use index for in-place processing. +double lineToLineDistance(const mapbox::geometry::line_string<double>& line1, + const mapbox::geometry::multi_point<double>& line2, + mapbox::cheap_ruler::CheapRuler& ruler) { + auto miniDist = ruler.distance(line1[0], line2[0]); + DistQueue distQueue; + distQueue.push(std::forward_as_tuple(0, IndexRange(0, line1.size() - 1), IndexRange(0, line2.size() - 1))); + + while (!distQueue.empty()) { + auto distPair = distQueue.top(); + distQueue.pop(); + if (std::get<0>(distPair) > miniDist) continue; + auto& rangeA = std::get<1>(distPair); + auto& rangeB = std::get<2>(distPair); + + // In case the set size are relatively small, we could use brute-force directly + if (getRangeSize(rangeA) <= MinLinePointsSize && getRangeSize(rangeB) <= MinLinePointsSize) { + miniDist = std::min(miniDist, lineToLineDistance(line1, rangeA, line2, rangeB, ruler)); + if (miniDist == 0.) return 0.; + } else { + auto newRangesA = splitRange(rangeA, true /*isLine*/); + auto newRangesB = splitRange(rangeB, true /*isLine*/); + const auto updateQueue = [&distQueue, &miniDist, &ruler, &line1, &line2]( + mbgl::optional<IndexRange>& range1, mbgl::optional<IndexRange>& range2) { + if (!range1 || !range2) return; + auto tempDist = bboxToBBoxDistance(getBBox(line1, *range1), getBBox(line2, *range2), ruler); + // Insert new pair to the queue if the bbox distance is less or equal to miniDist, + // The pair with biggest distance will be at the top + if (tempDist <= miniDist) + distQueue.push(std::make_tuple(tempDist, std::move(*range1), std::move(*range2))); + }; + updateQueue(newRangesA.first, newRangesB.first); + updateQueue(newRangesA.first, newRangesB.second); + updateQueue(newRangesA.second, newRangesB.first); + updateQueue(newRangesA.second, newRangesB.second); + } + } + return miniDist; +} + +// Divide and conqure, the time complexity is O(n*lgn), faster than Brute force O(n*n) +// Use index for in-place processing. +double pointsToPointsDistance(const mapbox::geometry::multi_point<double>& pointSet1, + const mapbox::geometry::multi_point<double>& pointSet2, + mapbox::cheap_ruler::CheapRuler& ruler) { + auto miniDist = ruler.distance(pointSet1[0], pointSet2[0]); + DistQueue distQueue; + distQueue.push(std::forward_as_tuple(0, IndexRange(0, pointSet1.size() - 1), IndexRange(0, pointSet2.size() - 1))); + + while (!distQueue.empty()) { + auto distPair = distQueue.top(); + distQueue.pop(); + if (std::get<0>(distPair) > miniDist) { + continue; + } + auto& rangeA = std::get<1>(distPair); + auto& rangeB = std::get<2>(distPair); + + // In case the set size are relatively small, we could use brute-force directly + if (getRangeSize(rangeA) <= MinPointsSize && getRangeSize(rangeB) <= MinPointsSize) { + miniDist = std::min(miniDist, pointsToPointsDistance(pointSet1, rangeA, pointSet2, rangeB, ruler)); + if (miniDist == 0.) return 0.; + } else { + auto newRangesA = splitRange(rangeA, false /*isLine*/); + auto newRangesB = splitRange(rangeB, false /*isLine*/); + const auto updateQueue = [&distQueue, &miniDist, &ruler, &pointSet1, &pointSet2]( + mbgl::optional<IndexRange>& range1, mbgl::optional<IndexRange>& range2) { + if (!range1 || !range2) return; + auto tempDist = bboxToBBoxDistance(getBBox(pointSet1, *range1), getBBox(pointSet2, *range2), ruler); + // Insert new pair to the queue if the bbox distance is less or equal to miniDist, + // The pair with biggest distance will be at the top + if (tempDist <= miniDist) + distQueue.push(std::make_tuple(tempDist, std::move(*range1), std::move(*range2))); + }; + updateQueue(newRangesA.first, newRangesB.first); + updateQueue(newRangesA.first, newRangesB.second); + updateQueue(newRangesA.second, newRangesB.first); + updateQueue(newRangesA.second, newRangesB.second); + } + } + return miniDist; +} + +// Divide and conqure, the time complexity is O(n*lgn), faster than Brute force O(n*n) +// Most of the time, use index for in-place processing. +double pointsToLineDistance(const mapbox::geometry::multi_point<double>& points, + const mapbox::geometry::line_string<double>& line, + mapbox::cheap_ruler::CheapRuler& ruler) { + auto miniDist = ruler.distance(points[0], line[0]); + DistQueue distQueue; + distQueue.push(std::forward_as_tuple(0, IndexRange(0, points.size() - 1), IndexRange(0, line.size() - 1))); + + while (!distQueue.empty()) { + auto distPair = distQueue.top(); + distQueue.pop(); + if (std::get<0>(distPair) > miniDist) continue; + auto& rangeA = std::get<1>(distPair); + auto& rangeB = std::get<2>(distPair); + + // In case the set size are relatively small, we could use brute-force directly + if (getRangeSize(rangeA) <= MinPointsSize && getRangeSize(rangeB) <= MinLinePointsSize) { + auto subLine = + mapbox::geometry::multi_point<double>(line.begin() + rangeB.first, line.begin() + rangeB.second + 1); + for (std::size_t i = rangeA.first; i <= rangeA.second; ++i) { + miniDist = std::min(miniDist, pointToLineDistance(points[i], subLine, ruler)); + if (miniDist == 0.) return 0.; + } + } else { + auto newRangesA = splitRange(rangeA, false /*isLine*/); + auto newRangesB = splitRange(rangeB, true /*isLine*/); + const auto updateQueue = [&distQueue, &miniDist, &ruler, &points, &line]( + mbgl::optional<IndexRange>& range1, mbgl::optional<IndexRange>& range2) { + if (!range1 || !range2) return; + auto tempDist = bboxToBBoxDistance(getBBox(points, *range1), getBBox(line, *range2), ruler); + // Insert new pair to the queue if the bbox distance is less or equal to miniDist, + // The pair with biggest distance will be at the top + if (tempDist <= miniDist) + distQueue.push(std::make_tuple(tempDist, std::move(*range1), std::move(*range2))); + }; + updateQueue(newRangesA.first, newRangesB.first); + updateQueue(newRangesA.first, newRangesB.second); + updateQueue(newRangesA.second, newRangesB.first); + updateQueue(newRangesA.second, newRangesB.second); + } + } + return miniDist; +} + +double pointsToLinesDistance(const mapbox::geometry::multi_point<double>& points, + const mapbox::geometry::multi_line_string<double>& lines, + mapbox::cheap_ruler::CheapRuler& ruler) { + double dist = std::numeric_limits<double>::infinity(); + for (const auto& line : lines) { + dist = std::min(dist, pointsToLineDistance(points, line, ruler)); + if (dist == 0.) return dist; + } + return dist; +} + +double lineToLinesDistance(const mapbox::geometry::line_string<double>& line, + const mapbox::geometry::multi_line_string<double>& lines, + mapbox::cheap_ruler::CheapRuler& ruler) { + double dist = std::numeric_limits<double>::infinity(); + for (const auto& l : lines) { + dist = std::min(dist, lineToLineDistance(line, l, ruler)); + if (dist == 0.) return dist; + } + return dist; +} + +double pointsToGeometryDistance(const mapbox::geometry::multi_point<double>& points, + const Feature::geometry_type& geoSet, + mapbox::cheap_ruler::CheapRuler::Unit unit) { + mapbox::cheap_ruler::CheapRuler ruler(points.front().y, unit); + return geoSet.match( + [&points, &ruler](const mapbox::geometry::point<double>& p) { + return pointsToPointsDistance(mapbox::geometry::multi_point<double>{p}, points, ruler); + }, + [&points, &ruler](const mapbox::geometry::multi_point<double>& points1) { + return pointsToPointsDistance(points, points1, ruler); + }, + [&points, &ruler](const mapbox::geometry::line_string<double>& line) { + return pointsToLineDistance(points, line, ruler); + }, + [&points, &ruler](const mapbox::geometry::multi_line_string<double>& lines) { + return pointsToLinesDistance(points, lines, ruler); + }, + [](const auto&) { return std::numeric_limits<double>::quiet_NaN(); }); +} + +double lineToGeometryDistance(const mapbox::geometry::line_string<double>& line, + const Feature::geometry_type& geoSet, + mapbox::cheap_ruler::CheapRuler::Unit unit) { + assert(!line.empty()); + mapbox::cheap_ruler::CheapRuler ruler(line.front().y, unit); + return geoSet.match( + [&line, &ruler](const mapbox::geometry::point<double>& p) { + return pointsToLineDistance(mapbox::geometry::multi_point<double>{p}, line, ruler); + }, + [&line, &ruler](const mapbox::geometry::multi_point<double>& points) { + return pointsToLineDistance(points, line, ruler); + }, + [&line, &ruler](const mapbox::geometry::line_string<double>& line1) { + return lineToLineDistance(line, line1, ruler); + }, + [&line, &ruler](const mapbox::geometry::multi_line_string<double>& lines) { + return lineToLinesDistance(line, lines, ruler); + }, + [](const auto&) { return std::numeric_limits<double>::quiet_NaN(); }); +} + +double calculateDistance(const GeometryTileFeature& feature, + const CanonicalTileID& canonical, + const Feature::geometry_type& geoSet, + mapbox::cheap_ruler::CheapRuler::Unit unit) { + return convertGeometry(feature, canonical) + .match( + [&geoSet, &unit](const mapbox::geometry::point<double>& point) -> double { + return pointsToGeometryDistance(mapbox::geometry::multi_point<double>{point}, geoSet, unit); + }, + [&geoSet, &unit](const mapbox::geometry::multi_point<double>& points) -> double { + return pointsToGeometryDistance(points, geoSet, unit); + }, + [&geoSet, &unit](const mapbox::geometry::line_string<double>& line) -> double { + return lineToGeometryDistance(line, geoSet, unit); + }, + [&geoSet, &unit](const mapbox::geometry::multi_line_string<double>& lines) -> double { + double dist = std::numeric_limits<double>::infinity(); + for (const auto& line : lines) { + dist = std::min(dist, lineToGeometryDistance(line, geoSet, unit)); + if (dist == 0.) return dist; + } + return dist; + }, + [](const auto&) -> double { return std::numeric_limits<double>::quiet_NaN(); }); +} + +struct Arguments { + Arguments(GeoJSON& geojson_, mapbox::cheap_ruler::CheapRuler::Unit unit_) + : geojson(std::move(geojson_)), unit(unit_) {} + + GeoJSON geojson; + mapbox::cheap_ruler::CheapRuler::Unit unit; +}; + +optional<Arguments> parseValue(const style::conversion::Convertible& value, style::expression::ParsingContext& ctx) { + if (isArray(value)) { + // object value, quoted with ["Distance", GeoJSONObj, "unit(optional)"] + auto length = arrayLength(value); + if (length != 2 && length != 3) { + ctx.error("'distance' expression requires either one argument or two arguments, but found " + + util::toString(arrayLength(value) - 1) + " instead."); + return nullopt; + } + + // Parse Unit info for distance calculation, "Meters" by default + mapbox::cheap_ruler::CheapRuler::Unit unit = mapbox::cheap_ruler::CheapRuler::Unit::Meters; + if (length == 3) { + auto input = toString(arrayMember(value, 2)); + if (input == nullopt) { + ctx.error("Failed to parse unit argument from 'distance' expression"); + return nullopt; + } + if (*input == "Meters" || *input == "Metres") { + unit = mapbox::cheap_ruler::CheapRuler::Unit::Meters; + } else if (*input == "Kilometers") { + unit = mapbox::cheap_ruler::CheapRuler::Unit::Kilometers; + } else if (*input == "Miles") { + unit = mapbox::cheap_ruler::CheapRuler::Unit::Miles; + } else if (*input == "NauticalMiles") { + unit = mapbox::cheap_ruler::CheapRuler::Unit::NauticalMiles; + } else if (*input == "Yards") { + unit = mapbox::cheap_ruler::CheapRuler::Unit::Kilometers; + } else if (*input == "Feet") { + unit = mapbox::cheap_ruler::CheapRuler::Unit::Miles; + } else if (*input == "Inches") { + unit = mapbox::cheap_ruler::CheapRuler::Unit::Inches; + } else { + ctx.error( + "'distance' expression only accepts following Units: 'Kilometers', 'Miles', 'NauticalMiles', " + "'Meters', 'Metres', 'Yards', 'Feet', 'Inches'."); + return nullopt; + } + } + // Parse geometry info + const auto& argument1 = arrayMember(value, 1); + if (isObject(argument1)) { + style::conversion::Error error; + auto geojson = toGeoJSON(argument1, error); + if (geojson && error.message.empty()) { + return Arguments(*geojson, unit); + } + ctx.error(error.message); + } + } + ctx.error( + "'distance' expression needs to be an array with format [\"Distance\", GeoJSONObj, \"unit(optional, Meters by " + "default)\"]."); + return nullopt; +} + +optional<Feature::geometry_type> getGeometry(const Feature& feature, mbgl::style::expression::ParsingContext& ctx) { + const auto type = apply_visitor(ToFeatureType(), feature.geometry); + if (type == FeatureType::Point || type == FeatureType::LineString) { + return feature.geometry; + } + ctx.error("'distance' expression requires valid geojson object with valid geometry type: Point/LineString."); + return nullopt; +} +} // namespace + +namespace style { +namespace expression { + +Distance::Distance(GeoJSON geojson, Feature::geometry_type geometries_, mapbox::cheap_ruler::CheapRuler::Unit unit_) + : Expression(Kind::Distance, type::Number), + geoJSONSource(std::move(geojson)), + geometries(std::move(geometries_)), + unit(unit_) {} + +Distance::~Distance() = default; + +using namespace mbgl::style::conversion; + +EvaluationResult Distance::evaluate(const EvaluationContext& params) const { + if (!params.feature || !params.canonical) { + return EvaluationError{"distance expression requirs valid feature and canonical information."}; + } + auto geometryType = params.feature->getType(); + if (geometryType == FeatureType::Point || geometryType == FeatureType::LineString) { + auto distance = calculateDistance(*params.feature, *params.canonical, geometries, unit); + if (!std::isnan(distance)) { + return distance; + } + } + return EvaluationError{"distance expression currently only evaluates Point/LineString geometries."}; +} + +ParseResult Distance::parse(const Convertible& value, ParsingContext& ctx) { + auto parsedValue = parseValue(value, ctx); + if (!parsedValue) { + return ParseResult(); + } + + return parsedValue->geojson.match( + [&parsedValue, &ctx](const mapbox::geometry::geometry<double>& geometrySet) { + if (auto ret = getGeometry(mbgl::Feature(geometrySet), ctx)) { + return ParseResult( + std::make_unique<Distance>(parsedValue->geojson, std::move(*ret), parsedValue->unit)); + } + return ParseResult(); + }, + [&parsedValue, &ctx](const mapbox::feature::feature<double>& feature) { + if (auto ret = getGeometry(mbgl::Feature(feature), ctx)) { + return ParseResult( + std::make_unique<Distance>(parsedValue->geojson, std::move(*ret), parsedValue->unit)); + } + return ParseResult(); + }, + [&parsedValue, &ctx](const mapbox::feature::feature_collection<double>& features) { + for (const auto& feature : features) { + if (auto ret = getGeometry(mbgl::Feature(feature), ctx)) { + return ParseResult( + std::make_unique<Distance>(parsedValue->geojson, std::move(*ret), parsedValue->unit)); + } + } + return ParseResult(); + }, + [&ctx](const auto&) { + ctx.error("'distance' expression requires valid geojson that contains LineString/Point geometries."); + return ParseResult(); + }); + + return ParseResult(); +} + +Value convertValue(const mapbox::geojson::rapidjson_value& v) { + if (v.IsDouble()) { + return v.GetDouble(); + } + if (v.IsString()) { + return std::string(v.GetString()); + } + if (v.IsArray()) { + std::vector<Value> result; + result.reserve(v.Size()); + for (const auto& m : v.GetArray()) { + result.push_back(convertValue(m)); + } + return result; + } + if (v.IsObject()) { + std::unordered_map<std::string, Value> result; + for (const auto& m : v.GetObject()) { + result.emplace(m.name.GetString(), convertValue(m.value)); + } + return result; + } + // Ignore other types as valid geojson only contains above types. + return Null; +} + +std::string getUnits(const mapbox::cheap_ruler::CheapRuler::Unit& unit) { + switch (unit) { + case mapbox::cheap_ruler::CheapRuler::Kilometers: + return "Kilometers"; + case mapbox::cheap_ruler::CheapRuler::Miles: + return "Miles"; + case mapbox::cheap_ruler::CheapRuler::NauticalMiles: + return "NauticalMiles"; + case mapbox::cheap_ruler::CheapRuler::Meters: + return "Meters"; + case mapbox::cheap_ruler::CheapRuler::Yards: + return "Yards"; + case mapbox::cheap_ruler::CheapRuler::Feet: + return "Feet"; + case mapbox::cheap_ruler::CheapRuler::Inches: + return "Inches"; + default: + return "Error"; + } +} + +mbgl::Value Distance::serialize() const { + std::unordered_map<std::string, Value> serialized; + rapidjson::CrtAllocator allocator; + const mapbox::geojson::rapidjson_value value = mapbox::geojson::convert(geoJSONSource, allocator); + if (value.IsObject()) { + for (const auto& m : value.GetObject()) { + serialized.emplace(m.name.GetString(), convertValue(m.value)); + } + } else { + mbgl::Log::Error(mbgl::Event::General, + "Failed to serialize 'distance' expression, converted rapidJSON is not an object"); + } + return std::vector<mbgl::Value>{{getOperator(), *fromExpressionValue<mbgl::Value>(serialized), getUnits(unit)}}; +} + +bool Distance::operator==(const Expression& e) const { + if (e.getKind() == Kind::Distance) { + auto rhs = static_cast<const Distance*>(&e); + return geoJSONSource == rhs->geoJSONSource && geometries == rhs->geometries && unit == rhs->unit; + } + return false; +} + +std::vector<optional<Value>> Distance::possibleOutputs() const { + return {nullopt}; +} + +std::string Distance::getOperator() const { + return "distance"; +} + +} // namespace expression +} // namespace style +} // namespace mbgl |