The race is rotated with it's initial rotation in mind

- RaceXMLCreator now checks the bearing of the race with getLineAngle()
- Split some methods into functions so that it is more readable
#story[1096]

racevisionGame/src/main/java/mock/xml/RaceXMLCreator.java

@@ -92,11 +92,42 @@ public class RaceXMLCreator {
         return null;
     }
 
+    public static CompoundMark getWindwardGate(RaceXMLReader reader){
+        for (CompoundMark mark: reader.getCompoundMarks()){
+            if (mark.getName().equals("Windward Gate")) return mark;
+        }
+        return null;
+    }
+
+    public static CompoundMark getLeewardGate(RaceXMLReader reader){
+        for (CompoundMark mark: reader.getCompoundMarks()){
+            if (mark.getName().equals("Leeward Gate")) return mark;
+        }
+        return null;
+    }
+
     public static String alterRaceToWind(String s, double degrees) throws XMLReaderException, InvalidRaceDataException, JAXBException {
         RaceXMLReader reader = new RaceXMLReader(s, XMLFileType.ResourcePath);
 
         Race race = copyRace(reader);
 
+        double raceOriginalBearing = getLineAngle(getLeewardGate(reader).getMark1Position(), getWindwardGate(reader).getMark1Position());
+
+        double degreesToRotate = degrees - raceOriginalBearing;
+
+        alterRaceRotation(race, degreesToRotate);
+
+        JAXBContext context = JAXBContext.newInstance(Race.class);
+        Marshaller jaxbMarshaller = context.createMarshaller();
+        jaxbMarshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
+
+        StringWriter sw = new StringWriter();
+
+        jaxbMarshaller.marshal(race, sw);
+        return sw.toString();
+    }
+
+    public static void alterRaceRotation(Race race, double degrees){
         GPSCoordinate center = getCenter(race);
         for(Race.CourseLimit.Limit limit: race.getCourseLimit().getLimit()){
             GPSCoordinate rotatedLim = rotate(center, limitToGPSCoordinate(limit), degrees);
@@ -112,15 +143,6 @@ public class RaceXMLCreator {
                 mark.setTargetLng(String.valueOf(rotatedMark.getLongitude()));
             }
         }
-
-        JAXBContext context = JAXBContext.newInstance(Race.class);
-        Marshaller jaxbMarshaller = context.createMarshaller();
-        jaxbMarshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
-
-        StringWriter sw = new StringWriter();
-
-        jaxbMarshaller.marshal(race, sw);
-        return sw.toString();
     }
 
     public static GPSCoordinate limitToGPSCoordinate(Race.CourseLimit.Limit limit){
@@ -152,5 +174,10 @@ public class RaceXMLCreator {
         avgLng = avgLng/race.getCourseLimit().getLimit().size();
         return new GPSCoordinate(avgLat, avgLng);
     }
+    public static double getLineAngle(GPSCoordinate coord1, GPSCoordinate coord2){
+        double dx = coord1.getLongitude() - coord2.getLongitude();
+        double dy = coord1.getLatitude() - coord2.getLatitude();
+        return Math.atan2(dy, dx)/Math.PI * 180;
+    }
 
 }