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Track age of heading/speed/altitude; use this when deciding what to emit in FATSV format.

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This commit is contained in:
Oliver Jowett 2015-06-15 23:13:04 +01:00
parent 03b53c2d29
commit 4f861f653a
4 changed files with 81 additions and 39 deletions
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100
net_io.c
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@ -1422,11 +1422,25 @@ static void writeFATSV() {
for (a = Modes.aircrafts; a; a = a->next) {
int altValid = 0;
int alt = 0;
uint64_t altAge = 999999;
int groundValid = 0;
int ground = 0;
int latlonValid = 0;
uint64_t latlonAge = 999999;
int speedValid = 0;
uint64_t speedAge = 999999;
int trackValid = 0;
uint64_t trackAge = 999999;
uint64_t emittedAge;
int useful = 0;
uint64_t emittedMillisAgo;
int changed = 0;
char *p, *end;
// skip non-ICAO
@ -1441,60 +1455,71 @@ static void writeFATSV() {
continue;
}
emittedMillisAgo = (now - a->fatsv_last_emitted);
// don't emit more than once every five seconds
if (emittedMillisAgo < 5000) {
continue;
}
emittedAge = (now - a->fatsv_last_emitted);
if (a->bFlags & MODES_ACFLAGS_ALTITUDE_VALID) {
altValid = 1;
altValid = 1;
alt = a->altitude;
altAge = now - a->seenAltitude;
}
if (a->bFlags & MODES_ACFLAGS_AOG_VALID) {
groundValid = 1;
if (a->bFlags & MODES_ACFLAGS_AOG) {
// force zero altitude on ground
alt = 0;
altValid = 1;
altAge = 0;
ground = 1;
}
}
if (a->bFlags & MODES_ACFLAGS_LATLON_VALID) {
latlonValid = 1;
latlonAge = now - a->seenLatLon;
}
// if it's over 10,000 feet, don't emit more than once every 10 seconds
if (alt > 10000 && emittedMillisAgo < 10000) {
if (a->bFlags & MODES_ACFLAGS_HEADING_VALID) {
trackValid = 1;
trackAge = now - a->seenTrack;
}
if (a->bFlags & MODES_ACFLAGS_SPEED_VALID) {
speedValid = 1;
speedAge = now - a->seenSpeed;
}
// don't send mode S very often
if (!latlonValid && emittedAge < 30000) {
continue;
}
// disable if you want only ads-b
// also don't send mode S very often
if (!latlonValid) {
if (emittedMillisAgo < 30000) {
// if it hasn't changed altitude, heading, or speed much,
// don't update so often
changed = 0;
if (trackValid && abs(a->track - a->fatsv_emitted_track) >= 2) {
changed = 1;
}
if (speedValid && abs(a->speed - a->fatsv_emitted_speed) >= 25) {
changed = 1;
}
if (altValid && abs(alt - a->fatsv_emitted_altitude) >= 50) {
changed = 1;
}
if (!altValid || alt < 10000) {
// Below 10000 feet, emit up to every 5s when changing, 10s otherwise
if (changed && emittedAge < 5000)
continue;
if (!changed && emittedAge < 10000)
continue;
}
} else {
// if it hasn't changed altitude very much and it hasn't changed
// heading very much, don't update real often
if (abs(a->track - a->fatsv_emitted_track) < 2 && abs(alt - a->fatsv_emitted_altitude) < 50) {
if (alt < 10000) {
// it hasn't changed much but we're below 10,000 feet
// so update more frequently
if (emittedMillisAgo < 10000) {
continue;
}
} else {
// above 10,000 feet, don't update so often when it
// hasn't changed much
if (emittedMillisAgo < 30000) {
continue;
}
}
}
// Above 10000 feet, emit up to every 10s when changing, 30s otherwise
if (changed && emittedAge < 10000)
continue;
if (!changed && emittedAge < 30000)
continue;
}
p = prepareWrite(&Modes.fatsv_out, TSV_MAX_PACKET_SIZE);
@ -1513,12 +1538,14 @@ static void writeFATSV() {
p += snprintf(p, bufsize(p,end), "\tsquawk\t%04x", a->modeA);
}
if (altValid) {
// only emit alt, speed, latlon, track if they have been received since the last time
if (altValid && altAge < emittedAge) {
p += snprintf(p, bufsize(p,end), "\talt\t%d", alt);
useful = 1;
}
if (a->bFlags & MODES_ACFLAGS_SPEED_VALID) {
if (speedValid && speedAge < emittedAge) {
p += snprintf(p, bufsize(p,end), "\tspeed\t%d", a->speed);
useful = 1;
}
@ -1531,12 +1558,12 @@ static void writeFATSV() {
}
}
if (latlonValid) {
if (latlonValid && latlonAge < emittedAge) {
p += snprintf(p, bufsize(p,end), "\tlat\t%.5f\tlon\t%.5f", a->lat, a->lon);
useful = 1;
}
if (a->bFlags & MODES_ACFLAGS_HEADING_VALID) {
if (trackValid && trackAge < emittedAge) {
p += snprintf(p, bufsize(p,end), "\theading\t%d", a->track);
useful = 1;
}
@ -1559,6 +1586,7 @@ static void writeFATSV() {
a->fatsv_last_emitted = now;
a->fatsv_emitted_altitude = alt;
a->fatsv_emitted_track = a->track;
a->fatsv_emitted_speed = a->speed;
}
}