Fixes issue #104. Heading and Azimuth get computed now.

DataStructures/SegmentInformation.h

@@ -28,12 +28,13 @@ struct SegmentInformation {
     NodeID nameID;
     unsigned length;
     unsigned duration;
+    double bearing;
     short turnInstruction;
     bool necessary;
     SegmentInformation(const _Coordinate & loc, const NodeID nam, const unsigned len, const unsigned dur, const short tInstr, const bool nec) :
-            location(loc), nameID(nam), length(len), duration(dur), turnInstruction(tInstr), necessary(nec) {}
+            location(loc), nameID(nam), length(len), duration(dur), bearing(0.), turnInstruction(tInstr), necessary(nec) {}
     SegmentInformation(const _Coordinate & loc, const NodeID nam, const unsigned len, const unsigned dur, const short tInstr) :
-        location(loc), nameID(nam), length(len), duration(dur), turnInstruction(tInstr), necessary(tInstr != 0) {}
+        location(loc), nameID(nam), length(len), duration(dur), bearing(0.), turnInstruction(tInstr), necessary(tInstr != 0) {}
 };
 
 #endif /* SEGMENTINFORMATION_H_ */

Descriptors/DescriptionFactory.cpp

@@ -24,10 +24,18 @@ DescriptionFactory::DescriptionFactory() { }
 
 DescriptionFactory::~DescriptionFactory() { }
 
-double DescriptionFactory::GetAngleBetweenCoordinates() const {
-    return 0.;//GetAngleBetweenTwoEdges(previousCoordinate, currentCoordinate, nextCoordinate);
+double DescriptionFactory::GetAzimuth(const _Coordinate& A, const _Coordinate& B) const {
+    double lonDiff = (A.lon-B.lon)/100000.;
+    double angle = atan2(sin(lonDiff)*cos(B.lat/100000.),
+            cos(A.lat/100000.)*sin(B.lat/100000.)-sin(A.lat/100000.)*cos(B.lat/100000.)*cos(lonDiff));
+    angle*=180/M_PI;
+    while(angle < 0)
+        angle += 360;
+
+    return angle;
 }
 
+
 void DescriptionFactory::SetStartSegment(const PhantomNode & _startPhantom) {
     startPhantom = _startPhantom;
     AppendSegment(_startPhantom.location, _PathData(0, _startPhantom.nodeBasedEdgeNameID, 10, _startPhantom.weight1));
@@ -91,5 +99,12 @@ unsigned DescriptionFactory::Run(const unsigned zoomLevel) {
     dp.Run(pathDescription, zoomLevel);
 
     //fix what needs to be fixed else
+    for(unsigned i = 0; i < pathDescription.size()-1 && pathDescription.size() >= 2; ++i){
+        if(pathDescription[i].necessary) {
+            int angle = 100*GetAzimuth(pathDescription[i].location, pathDescription[i+1].location);
+            pathDescription[i].bearing = angle/100.;
+        }
+    }
+
     return entireLength;
 }

Descriptors/DescriptionFactory.h

@@ -41,7 +41,7 @@ public:
     std::vector <SegmentInformation> pathDescription;
     DescriptionFactory();
     virtual ~DescriptionFactory();
-    double GetAngleBetweenCoordinates() const;
+    double GetAzimuth(const _Coordinate& C, const _Coordinate& B) const;
     void AppendEncodedPolylineString(std::string &output);
     void AppendUnencodedPolylineString(std::string &output);
     void AppendSegment(const _Coordinate & coordinate, const _PathData & data);

Descriptors/JSONDescriptor.h

@@ -27,6 +27,7 @@ or see http://www.gnu.org/licenses/agpl.txt.
 #include "DescriptionFactory.h"
 #include "../DataStructures/SegmentInformation.h"
 #include "../DataStructures/TurnInstructions.h"
+#include "../Util/Azimuth.h"
 #include "../Util/StringUtil.h"
 
 template<class SearchEngineT>
@@ -36,6 +37,7 @@ private:
 	_RouteSummary summary;
 	DescriptionFactory descriptionFactory;
 	_Coordinate current;
+
 	struct {
 		int startIndex;
 		int nameID;
@@ -100,7 +102,7 @@ public:
 			unsigned prefixSumOfNecessarySegments = 0;
 			roundAbout.leaveAtExit = 0;
 			roundAbout.nameID = 0;
-			std::string tmpDist, tmpLength, tmpDuration;
+			std::string tmpDist, tmpLength, tmpDuration, tmpBearing;
 			//Fetch data from Factory and generate a string from it.
 			BOOST_FOREACH(SegmentInformation & segment, descriptionFactory.pathDescription) {
 				if(TurnInstructions.TurnIsNecessary( segment.turnInstruction) ) {
@@ -134,8 +136,11 @@ public:
 						reply.content += tmpDuration;
 						reply.content += ",\"";
 						reply.content += tmpLength;
-						//TODO: fix heading
-						reply.content += "\",\"NE\",22.5";
+						reply.content += "\",\"";
+						reply.content += Azimuth::Get(segment.bearing);
+						reply.content += "\",";
+						doubleToStringWithTwoDigitsBehindComma(segment.bearing, tmpBearing);
+						reply.content += tmpBearing;
 			            reply.content += "]";
 					}
 				} else if(TurnInstructions.StayOnRoundAbout == segment.turnInstruction) {

Util/StringUtil.h

@@ -93,6 +93,14 @@ static inline void doubleToString(const double value, std::string & output){
     output = buffer ;
 }
 
+static inline void doubleToStringWithTwoDigitsBehindComma(const double value, std::string & output){
+    // The largest 32-bit integer is 4294967295, that is 10 chars
+    // On the safe side, add 1 for sign, and 1 for trailing zero
+    char buffer[12] ;
+    sprintf(buffer, "%g", value) ;
+    output = buffer ;
+}
+
 inline std::string & replaceAll(std::string &s, const std::string &sub, const std::string &other) {
     assert(!sub.empty());
     size_t b = 0;