Fix review comments

src/midgard/util.cc

@@ -132,21 +132,13 @@ float tangent_angle(size_t index,
                     const PointLL& point,
                     const std::vector<PointLL>& shape,
                     const float sample_distance,
-                    bool forward) {
-  assert(!shape.empty());
-  return tangent_angle(index, 0, shape.size() - 1, point, shape, sample_distance, forward);
-}
-
-float tangent_angle(size_t index,
+                    bool forward,
                     size_t first_segment_index,
-                    size_t last_segment_index,
-                    const PointLL& point,
-                    const std::vector<PointLL>& shape,
-                    const float sample_distance,
-                    bool forward) {
-  // make sure that `index` belongs to the segment
-  assert(first_segment_index <= index);
-  assert(index <= last_segment_index);
+                    size_t last_segment_index) {
+  assert(!shape.empty());
+  assert(index < shape.size());
+  first_segment_index = std::min(first_segment_index, index);
+  last_segment_index = std::min(std::max(last_segment_index, index), shape.size() - 1);
   // depending on if we are going forward or backward we choose a different increment
   auto increment = forward ? -1 : 1;
   auto first_end =

src/tyr/serializers.cc

@@ -72,10 +72,10 @@ std::vector<std::string> openlr_edges(const TripLeg& leg) {
 
     const auto& start = shape[begin_index];
     float forward_heading =
-        midgard::tangent_angle(begin_index, begin_index, end_index, start, shape, 20.f, true);
+        midgard::tangent_angle(begin_index, start, shape, 20.f, true, begin_index, end_index);
     const auto& end = shape[end_index];
     float reverse_heading =
-        midgard::tangent_angle(end_index, begin_index, end_index, end, shape, 20.f, false);
+        midgard::tangent_angle(end_index, end, shape, 20.f, false, begin_index, end_index);
 
     std::vector<baldr::OpenLR::LocationReferencePoint> lrps;
     lrps.emplace_back(start.lng(), start.lat(), forward_heading, frc, fow, nullptr,

test/util_midgard.cc

@@ -630,12 +630,12 @@ TEST(UtilMidgard, TestTangentAngleOnSegment) {
 
   float expected = shape[1].Heading(shape[2]);
   // calculate the angle taking into account only second and third points on the curve
-  float tang = tangent_angle(1, 1, 2, shape[1], shape, kTestDistance, true);
+  float tang = tangent_angle(1, shape[1], shape, kTestDistance, true, 1, 2);
   EXPECT_NEAR(tang, expected, 5.0f) << "tangent_angle outside expected tolerance";
 
   expected = shape[1].Heading(shape[0]);
   // calculate the angle taking into account only first and second points on the curve
-  tang = tangent_angle(1, 0, 1, shape[1], shape, kTestDistance, false);
+  tang = tangent_angle(1, shape[1], shape, kTestDistance, false, 0, 1);
   EXPECT_NEAR(tang, expected, 5.0f) << "tangent_angle outside expected tolerance";
 }
 

valhalla/midgard/util.h

@@ -285,34 +285,17 @@ void trim_shape(float start,
  * @param shape  Shape / polyline geometry.
  * @param sample_distance Distance to sample when computing heading.
  * @param forward Boolean value whether to test in forward or reverse direction.
+ * @param first_segment_index Index into the shape pointing to the first stopping point.
+ * @param last_segment_index Index into the shape pointing to the last stopping point.
  * @return Returns the angle in degrees relative to N.
  */
 float tangent_angle(size_t index,
                     const PointLL& point,
                     const std::vector<PointLL>& shape,
                     const float sample_distance,
-                    bool forward);
-
-/**
- * Estimate the angle of the tangent at a point along a discretised curve. This is extended
- * function that allows to use a subcurve of the curve. It may be helpful in case you don't
- * want to create an additional vector by copying intermediate points.
- * @param index Index into the shape.
- * @param first_segment_index Index into the shape pointing to the first point of the segment.
- * @param last_segment_index Index into the shape pointing to the last point of the segment.
- * @param point Point to test for tangent along the curve.
- * @param shape  Shape / polyline geometry.
- * @param sample_distance Distance to sample when computing heading.
- * @param forward Boolean value whether to test in forward or reverse direction.
- * @return Returns the angle in degrees relative to N.
- */
-float tangent_angle(size_t index,
-                    size_t first_segment_index,
-                    size_t last_segment_index,
-                    const PointLL& point,
-                    const std::vector<PointLL>& shape,
-                    const float sample_distance,
-                    bool forward);
+                    bool forward,
+                    size_t first_segment_index = 0,
+                    size_t last_segment_index = std::numeric_limits<size_t>::max());
 
 // useful in converting from one iteratable map to another
 // for example: ToMap<boost::property_tree::ptree, std::unordered_map<std::string, std::string>