WIND_COV.hpp 3.22 KB
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#ifndef WIND_COV_HPP
#define WIND_COV_HPP

#include <uORB/topics/vehicle_local_position.h>
#include <uORB/topics/wind.h>

class MavlinkStreamWindCov : public MavlinkStream
{
public:
	static MavlinkStream *new_instance(Mavlink *mavlink) { return new MavlinkStreamWindCov(mavlink); }

	static constexpr const char *get_name_static() { return "WIND_COV"; }
	static constexpr uint16_t get_id_static() { return MAVLINK_MSG_ID_WIND_COV; }

	const char *get_name() const override { return get_name_static(); }
	uint16_t get_id() override { return get_id_static(); }

	unsigned get_size() override
	{
		return _wind_sub.advertised() ? MAVLINK_MSG_ID_WIND_COV_LEN + MAVLINK_NUM_NON_PAYLOAD_BYTES : 0;
	}

private:
	explicit MavlinkStreamWindCov(Mavlink *mavlink) : MavlinkStream(mavlink) {}

	uORB::Subscription _wind_sub{ORB_ID(wind)};
	uORB::Subscription _local_pos_sub{ORB_ID(vehicle_local_position)};

	bool send() override
	{
		wind_s wind;

		if (_wind_sub.update(&wind)) {
			mavlink_wind_cov_t msg{};

			msg.time_usec = wind.timestamp;

			msg.wind_x = wind.windspeed_north;
			msg.wind_y = wind.windspeed_east;
			msg.wind_z = 0.0f;

			msg.var_horiz = wind.variance_north + wind.variance_east;
			msg.var_vert = 0.0f;

			vehicle_local_position_s lpos{};
			_local_pos_sub.copy(&lpos);
			msg.wind_alt = (lpos.z_valid && lpos.z_global) ? (-lpos.z + lpos.ref_alt) : NAN;

			msg.horiz_accuracy = 0.0f;
			msg.vert_accuracy = 0.0f;

			mavlink_msg_wind_cov_send_struct(_mavlink->get_channel(), &msg);

			return true;
		}

		return false;
	}
};

#endif // WIND_COV