src/marnav/seatalk/message_53.hpp

   1 #ifndef MARNAV__SEATALK__MESSAGE_53__HPP
   2 #define MARNAV__SEATALK__MESSAGE_53__HPP
   3
   4 #include <marnav/seatalk/message.hpp>
   5 #include <marnav/geo/angle.hpp>
   6
   7 namespace marnav
   8 {
   9 namespace seatalk
  10 {
  11
  12 /// @brief Magnetic Course
  13 ///
  14 /// @code
  15 /// 53 U0 VW
  16 ///
  17 /// Magnetic Course in degrees:
  18 ///     The two lower  bits of  U * 90 +
  19 ///     the six lower  bits of VW *  2 +
  20 ///     the two higher bits of  U /  2 =
  21 ///     (U & 0x3) * 90 + (VW & 0x3F) * 2 + (U & 0xC) / 8
  22 /// @endcode
  23 ///
  24 /// The Magnetic Course may be offset by the Compass Variation (see datagram 99)
  25 /// to get the Course Over Ground (COG).
  26 ///
  27 /// Corresponding NMEA sentences: RMC, VTG
  28 ///
  29 class message_53 : public message
  30 {
  31 public:
  32         constexpr static const message_id ID = message_id::magnetic_course;
  33         constexpr static size_t SIZE = 3;
  34
  35         message_53();
  36         message_53(const message_53 &) = default;
  37         message_53 & operator=(const message_53 &) = default;
  38
  39         virtual raw get_data() const override;
  40
  41         static std::unique_ptr<message> parse(const raw & data);
  42
  43 private:
  44         double cog_;
  45
  46 public:
  47         /// Returns the COG in degrees.
  48         double get_cog() const noexcept { return cog_; }
  49
  50         void set_cog(double t) noexcept;
  51 };
  52 }
  53 }
  54
  55 #endif