GPS/GPS.h

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#ifndef GPS_h_GAURD_123412341
#define GPS_h_GAURD_123412341

#include <math.h>

class GPS {
  public:
        enum {Static=1, Quasi_Static=2, Walking=3, Ship=4, Automobile=5, Aircraft=6};
        
        
        // The constuctor will open and initialize serial port. You should use reset() 
        // after this function to reset the GPS. 
        GPS(const char* serial, int noWait=1);

        // This will create a empty class, ReadNoWait will not work, but the parsePOS and
        // parseUTM functions can be used for parsing POS or UTM messages; Usefull for 
        // debugging 
        GPS(void);  

        // This function will reset and initialize GPS settings, it will take about 
        // 10-20 seconds for this fucntion to compelete.  After being intialized the GPS 
        // should start sending data almost immediately, but it will take about 
        // 60+ seconds for the GPS unit to get a lock on enough satelites to provide  
        // position data
        int init(float period=5.0, int dynamicMode=Quasi_Static);
    
        // Will read data from GPS. Tf there is new data it save it and return 1.
        // If there is no new data it will return 0;
        int Read(void);
  
        // Message access functions : If last called to ReadNoWait() returned 1, then 
        // The data that was collected can be found here.  When there is not enough
        // satellites availible the may not be accurate position or velocity data availible
        // so use the hasPositions() and hasVelocities() functions to check this.
        // returns non-zero if there was position data availble with last read
        // the postion data can be obtained with xPos() yPos() and zPos()
        inline int hasPositions(void) {return has_positions;}
        inline double xPos(void) {return x;}
        inline double yPos(void) {return y;}
        inline double zPos(void) {return z;}
        // returns non-zero if there was velocity data availble with last read
        // the velocity data can be obtained with xVel() yVel() and zVel()
        inline int hasVelocities(void) {return has_velocities;}
        inline double xVel(void) {return xvel;}
        inline double yVel(void) {return yvel;}
        inline double zVel(void) {return zvel;}
        inline double pDOP(void) {return pdop;}
        inline double hDOP(void) {return hdop;}
        inline double vDOP(void) {return vdop;}
        inline double tDOP(void) {return tdop;}
        // number of satelites that were seen with last read
        inline int getNumSat(void) {return numsat;}  
        inline double getLatitude(void) {return latitude;}
        inline double getLongitude(void) {return longitude;}
        // Returns a pointer to last message read from GPS.  Could be use for logging 
        // data to a file.
        inline const char* getMsg(void) {return msgbuf;}
        inline int getFD(void) {return gps_fd;}
        // These functions will parse different types of messages from 
        int dispatchMsg(const char *msg); //dispatch to correct message parsing type
        int parsePOS(const char *msg);
        int parseUTM(const char *msg);

        // Prints out data from last GPS message (for debugging)
        void printData(void);



        // INTERNAL STUFF

  private:
        void initVars(void);

  protected:
        char msgbuf[200];
        int msglen;
        int gps_fd;
        int reading;  //set if class is reading input
        int using_file;  //set if the input if comming from a file (not the GPS through serial)

        //parsed data
        int numsat;
        char NorS, EorW;
        double latitude, longitude, altitude;
        double x,y,z;
        double hVelocity, vVelocity, direction;
        double xvel, yvel, zvel;
        double pdop, hdop, vdop, tdop;  

        //flags
        int is_corrected;
        int has_positions, has_velocities;
        int nowait;

        static const double minutes2radians = (M_PI / 180.0 / 60.0);
        static const double degrees2radians = (M_PI / 180.0f);
        static const double knots2mps = 0.5144444;  //mps = meters per second
        static double invalid;; // use as invalid value? - what about NAN?
        static const double earthRadius = 6378137.0f; //in meters

        static const double zeroLatitude = 0.700076f;
        static const double zeroLongitude = 1.53984f;

        //internal functions
        int readLine(void);
        int writeLine(const char* msg);
        int checkAck(void);

        inline float cos(float f) {return ::cosf(f);}
        inline double cos(double f) {return ::cos(f);}
        inline float sin(float f) {return ::sinf(f);}
        inline double sin(double f) {return ::sin(f);}
        
  public:
        ~GPS();

};


#endif

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