handle intersection-access for roundabout correctly

features/guidance/roundabout-turn.feature

@@ -367,3 +367,25 @@ Feature: Basic Roundabout
            | h,d       | gh,cd,cd | depart,roundabout-exit-2,arrive |
            | h,f       | gh,ef,ef | depart,roundabout-exit-1,arrive |
 
+    Scenario: Enter and Exit -- Bearing
+        Given the node map
+           |   |   | a |   |   |
+           |   |   | b |   |   |
+           | h | g |   | c | d |
+           |   |   | e |   |   |
+           |   |   | f |   |   |
+
+       And the ways
+            | nodes | junction   |
+            | ab    |            |
+            | cd    |            |
+            | ef    |            |
+            | gh    |            |
+            | bgecb | roundabout |
+
+       When I route I should get
+           | waypoints | route    | turns                                         | bearing                |
+           | a,d       | ab,cd,cd | depart,roundabout turn left exit-3,arrive     | 0->180,180->224,90->0  |
+           | a,f       | ab,ef,ef | depart,roundabout turn straight exit-2,arrive | 0->180,180->224,180->0 |
+           | a,h       | ab,gh,gh | depart,roundabout turn right exit-1,arrive    | 0->180,180->224,270->0 |
+

features/guidance/roundabout.feature

@@ -337,3 +337,27 @@ Feature: Basic Roundabout
             | a,e       | ac,de,de | depart,roundabout-exit-1,arrive |
             | a,f       | ac,bf,bf | depart,roundabout-exit-2,arrive |
 
+    Scenario: Enter and Exit - Bearings
+        Given the node map
+            |   |   |   | a |   |   |   |
+            |   |   |   |   |   |   |   |
+            |   |   | i | b | l |   |   |
+            | h |   | g |   | c |   | d |
+            |   |   | j | e | k |   |   |
+            |   |   |   |   |   |   |   |
+            |   |   |   | f |   |   |   |
+
+       And the ways
+            | nodes      | junction   |
+            | ab         |            |
+            | cd         |            |
+            | ef         |            |
+            | gh         |            |
+            | bigjekclb  | roundabout |
+
+       When I route I should get
+           | waypoints | route    | turns                           | bearing                |
+           | a,d       | ab,cd,cd | depart,roundabout-exit-3,arrive | 0->180,180->270,90->0  |
+           | a,f       | ab,ef,ef | depart,roundabout-exit-2,arrive | 0->180,180->270,180->0 |
+           | a,h       | ab,gh,gh | depart,roundabout-exit-1,arrive | 0->180,180->270,270->0 |
+

src/engine/guidance/post_processing.cpp

@@ -41,11 +41,11 @@ void print(const std::vector<RouteStep> &steps)
     int segment = 0;
     for (const auto &step : steps)
     {
-        std::cout << "\t[" << ++segment << "]: " << step.maneuver.instruction.type
+        std::cout << "\t[" << ++segment << "]: " << step.maneuver.instruction.type << " "
-                  << " " << step.maneuver.instruction.direction_modifier << "  " << static_cast<int>(step.maneuver.waypoint_type)
+                  << step.maneuver.instruction.direction_modifier << "  "
-                  << " Duration: " << step.duration << " Distance: " << step.distance
+                  << static_cast<int>(step.maneuver.waypoint_type) << " Duration: " << step.duration
-                  << " Geometry: " << step.geometry_begin << " " << step.geometry_end
+                  << " Distance: " << step.distance << " Geometry: " << step.geometry_begin << " "
-                  << " exit: " << step.maneuver.exit
+                  << step.geometry_end << " exit: " << step.maneuver.exit
                   << " Intersections: " << step.intersections.size() << " [";
 
         for (const auto &intersection : step.intersections)
@@ -203,7 +203,9 @@ void closeOffRoundabout(const bool on_roundabout,
     // removal.
     std::vector<std::size_t> intermediate_steps;
     BOOST_ASSERT(!steps[step_index].intersections.empty());
-    const auto exit_intersection = steps[step_index].intersections.back();
+    // the very first intersection in the steps represents the location of the turn. Following
+    // intersections are locations passed along the way
+    const auto exit_intersection = steps[step_index].intersections.front();
     const auto exit_bearing = exit_intersection.bearings[exit_intersection.out];
     if (step_index > 1)
     {
@@ -250,7 +252,8 @@ void closeOffRoundabout(const bool on_roundabout,
                     // All other cases are handled by first rotating both bearings to an
                     // entry_bearing of 0.
                     BOOST_ASSERT(!propagation_step.intersections.empty());
-                    const double angle = [](const double entry_bearing, const double exit_bearing) {
+                    const double angle =
+                        [](const double entry_bearing, const double exit_bearing) {
                             const double offset = 360 - entry_bearing;
                             const double rotated_exit = [](double bearing, const double offset) {
                                 bearing += offset;
@@ -259,7 +262,9 @@ void closeOffRoundabout(const bool on_roundabout,
 
                             const auto angle = 540 - rotated_exit;
                             return angle > 360 ? angle - 360 : angle;
-                    }(util::bearing::reverseBearing(entry_intersection.bearings[entry_intersection.in]), exit_bearing);
+                        }(util::bearing::reverseBearing(
+                              entry_intersection.bearings[entry_intersection.in]),
+                          exit_bearing);
 
                     propagation_step.maneuver.instruction.direction_modifier =
                         ::osrm::util::guidance::getTurnDirection(angle);
@@ -378,8 +383,11 @@ void collapseTurnAt(std::vector<RouteStep> &steps,
         }
     }
     // Potential U-Turn
-    else if (bearingsAreReversed(util::bearing::reverseBearing(one_back_step.intersections.front().bearings[one_back_step.intersections.front().in]),
+    else if (bearingsAreReversed(util::bearing::reverseBearing(
-                                 current_step.intersections.front().bearings[current_step.intersections.front().out]))
+                                     one_back_step.intersections.front()
+                                         .bearings[one_back_step.intersections.front().in]),
+                                 current_step.intersections.front()
+                                     .bearings[current_step.intersections.front().out]))
 
     {
         BOOST_ASSERT(two_back_index < steps.size());
@@ -755,7 +763,6 @@ void trimShortSegments(std::vector<RouteStep> &steps, LegGeometry &geometry)
     if (steps.size() < 2 || geometry.locations.size() == 2)
         return;
 
-
     BOOST_ASSERT(geometry.locations.size() >= steps.size());
     auto &next_to_last_step = *(steps.end() - 2);
     // in the end, the situation with the roundabout cannot occur. As a result, we can remove