ardupilot/libraries/AP_AHRS/AP_AHRS_HIL.h

#ifndef AP_AHRS_HIL_H
#define AP_AHRS_HIL_H

class AP_AHRS_HIL : public AP_AHRS
{
public:
    // Constructors
    AP_AHRS_HIL(IMU *imu, GPS *&gps) : AP_AHRS(imu, gps)
    {
    }

    // Accessors
    Vector3f get_gyro(void) {
        return _omega;
    }

    Matrix3f get_dcm_matrix(void) {
        Matrix3f m;
        m.from_euler(roll, pitch, yaw);
        return m;
    }

    // Methods
    void            update(void) {
    }
    void            setHil(float roll, float pitch, float yaw,
                           float rollRate, float pitchRate, float yawRate);

    // return the current estimate of the gyro drift
    Vector3f get_gyro_drift(void) {
        return Vector3f(0,0,0);
    }

    // reset the current attitude, used on new IMU calibration
    void reset(bool recover_eulers=false) {
    }

    float get_error_rp(void) {
        return 0;
    }
    float get_error_yaw(void) {
        return 0;
    }

private:
    Vector3f _omega;
};

#endif