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package nmea
const (
// TypeBWC type of BWC sentence for bearing and distance to waypoint, great circle
TypeBWC = "BWC"
)
// BWC - bearing and distance to waypoint, great circle
// https://gpsd.gitlab.io/gpsd/NMEA.html#_bwc_bearing_distance_to_waypoint_great_circle
// http://aprs.gids.nl/nmea/#bwc
//
// Format: $--BWC,hhmmss.ss,llll.ll,a,yyyyy.yy,a,x.x,T,x.x,M,x.x,N,c--c*hh<CR><LF>
// Format (NMEA 2.3+): $--BWC,hhmmss.ss,llll.ll,a,yyyyy.yy,a,x.x,T,x.x,M,x.x,N,c--c,m*hh<CR><LF>
// Example: $GPBWC,081837,,,,,,T,,M,,N,*13
// $GPBWC,220516,5130.02,N,00046.34,W,213.8,T,218.0,M,0004.6,N,EGLM*21
type BWC struct {
BaseSentence
Time Time // UTC Time
Latitude float64 // latitude of waypoint
Longitude float64 // longitude of waypoint
BearingTrue float64 // true bearing in degrees
BearingTrueType string // is type of true bearing
BearingMagnetic float64 // magnetic bearing in degrees
BearingMagneticType string // is type of magnetic bearing
DistanceNauticalMiles float64 // distance to waypoint in nautical miles
DistanceNauticalMilesUnit string // is unit of distance to waypoint nautical miles
DestinationWaypointID string // destination waypoint ID
FFAMode string // FAA mode indicator (filled in NMEA 2.3 and later)
}
// newBWC constructor
func newBWC(s BaseSentence) (Sentence, error) {
p := NewParser(s)
p.AssertType(TypeBWC)
bwc := BWC{
BaseSentence: s,
Time: p.Time(0, "time"),
Latitude: p.LatLong(1, 2, "latitude"),
Longitude: p.LatLong(3, 4, "longitude"),
BearingTrue: p.Float64(5, "true bearing"),
BearingTrueType: p.EnumString(6, "true bearing type", BearingTrue),
BearingMagnetic: p.Float64(7, "magnetic bearing"),
BearingMagneticType: p.EnumString(8, "magnetic bearing type", BearingMagnetic),
DistanceNauticalMiles: p.Float64(9, "distance to waypoint is nautical miles"),
DistanceNauticalMilesUnit: p.EnumString(10, "is distance to waypoint nautical miles unit", DistanceUnitNauticalMile),
DestinationWaypointID: p.String(11, "destination waypoint ID"),
}
if len(p.Fields) > 12 {
bwc.FFAMode = p.String(12, "FAA mode") // not enum because some devices have proprietary "non-nmea" values
}
return bwc, p.Err()
}
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