Add support for opposite approach request parameter (#6842)

* Added approach on the opposite side of the road.

* Additional test and docs coverage for opposite approach

---------

Co-authored-by: Aleksandrs Saveljevs <Aleksandrs.Saveljevs@gmail.com>

include/engine/api/base_parameters.hpp

@@ -52,7 +52,8 @@ namespace osrm::engine::api
  *              optional per coordinate
  *  - bearings: limits the search for segments in the road network to given bearing(s) in degree
  *              towards true north in clockwise direction, optional per coordinate
- *  - approaches: force the phantom node to start towards the node with the road country side.
+ *  - approaches: force the phantom node to start towards the node with the road country side or
+ *                its opposite
  *
  * \see OSRM, Coordinate, Hint, Bearing, RouteParameters, TableParameters,
  *      NearestParameters, TripParameters, MatchParameters and TileParameters

include/engine/approach.hpp

@@ -36,7 +36,8 @@ namespace osrm::engine
 enum class Approach : std::uint8_t
 {
     CURB = 0,
-    UNRESTRICTED = 1
+    UNRESTRICTED = 1,
+    OPPOSITE = 2
 
 };
 } // namespace osrm::engine

include/engine/geospatial_query.hpp

@@ -558,7 +558,7 @@ template <typename RTreeT, typename DataFacadeT> class GeospatialQuery
     {
         bool isOnewaySegment =
             !(segment.data.forward_segment_id.enabled && segment.data.reverse_segment_id.enabled);
-        if (!isOnewaySegment && approach == Approach::CURB)
+        if (!isOnewaySegment && (approach == Approach::CURB || approach == Approach::OPPOSITE))
         {
             // Check the counter clockwise
             //
@@ -573,6 +573,9 @@ template <typename RTreeT, typename DataFacadeT> class GeospatialQuery
             if (datafacade.IsLeftHandDriving(segment.data.forward_segment_id.id))
                 input_coordinate_is_at_right = !input_coordinate_is_at_right;
 
+            if (approach == Approach::OPPOSITE)
+                input_coordinate_is_at_right = !input_coordinate_is_at_right;
+
             return std::make_pair(input_coordinate_is_at_right, (!input_coordinate_is_at_right));
         }
         return std::make_pair(true, true);

include/nodejs/node_osrm_support.hpp

@@ -560,6 +560,10 @@ inline bool argumentsToParameter(const Napi::CallbackInfo &args,
                 {
                     params->approaches.push_back(osrm::Approach::CURB);
                 }
+                else if (approach_str == "opposite")
+                {
+                    params->approaches.push_back(osrm::Approach::OPPOSITE);
+                }
                 else if (approach_str == "unrestricted")
                 {
                     params->approaches.push_back(osrm::Approach::UNRESTRICTED);
@@ -567,13 +571,14 @@ inline bool argumentsToParameter(const Napi::CallbackInfo &args,
                 else
                 {
                     ThrowError(args.Env(),
-                               "'approaches' param must be one of [curb, unrestricted]");
+                               "'approaches' param must be one of [curb, opposite, unrestricted]");
                     return false;
                 }
             }
             else
             {
-                ThrowError(args.Env(), "Approach must be a string: [curb, unrestricted] or null");
+                ThrowError(args.Env(),
+                           "Approach must be a string: [curb, opposite, unrestricted] or null");
                 return false;
             }
         }

include/server/api/base_parameters_grammar.hpp

@@ -166,8 +166,9 @@ struct BaseParametersGrammar : boost::spirit::qi::grammar<Iterator, Signature>
             qi::lit("bearings=") >
             (-(qi::short_ > ',' > qi::short_))[ph::bind(add_bearing, qi::_r1, qi::_1)] % ';';
 
-        approach_type.add("unrestricted", engine::Approach::UNRESTRICTED)("curb",
-                                                                          engine::Approach::CURB);
+        approach_type.add("unrestricted", engine::Approach::UNRESTRICTED)(
+            "curb", engine::Approach::CURB)("opposite", engine::Approach::OPPOSITE);
+
         approach_rule = qi::lit("approaches=") >
                         (-approach_type %
                          ';')[ph::bind(&engine::api::BaseParameters::approaches, qi::_r1) = qi::_1];