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Overhaul mode A/C matching to be much cheaper.

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The old matching process which tracked mode A values as pseudo-aircraft
got very, very expensive with a large number of mode A/C messages (and
with lots of single-bit errors, which seems common with a Beast doing
the reception)

Instead just count A/C messages directly into a 4096-entry array (which
is very fast) and periodically scan the mode S aircraft list to see if
we can match anything up (which is fixed overhead + cost proportional
to the number of mode S aircraft)
This commit is contained in:
Oliver Jowett 2016-10-11 18:00:11 +01:00
parent 60f1f3bcb6
commit 25ea6d398b
6 changed files with 111 additions and 140 deletions
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47
interactive.c
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@ -111,12 +111,8 @@ void interactiveShowData(void) {
if ((now - a->seen) < Modes.interactive_display_ttl)
{
int msgs = a->messages;
int flags = a->modeACflags;
if ( (((flags & (MODEAC_MSG_FLAG )) == 0 ) && (msgs > 1 ) )
|| (((flags & (MODEAC_MSG_MODES_HIT | MODEAC_MSG_MODEA_ONLY)) == MODEAC_MSG_MODEA_ONLY) && (msgs > 4 ) )
|| (((flags & (MODEAC_MSG_MODES_HIT | MODEAC_MSG_MODEC_OLD )) == 0 ) && (msgs > 127) )
) {
if (msgs > 1) {
char strSquawk[5] = " ";
char strFl[7] = " ";
char strTt[5] = " ";
@ -153,13 +149,9 @@ void interactiveShowData(void) {
double signalAverage = (pSig[0] + pSig[1] + pSig[2] + pSig[3] +
pSig[4] + pSig[5] + pSig[6] + pSig[7]) / 8.0;
if ((flags & MODEAC_MSG_FLAG) == 0) {
strMode[0] = 'S';
} else if (flags & MODEAC_MSG_MODEA_ONLY) {
strMode[0] = 'A';
}
if (flags & MODEAC_MSG_MODEA_HIT) {strMode[2] = 'a';}
if (flags & MODEAC_MSG_MODEC_HIT) {strMode[3] = 'c';}
strMode[0] = 'S';
if (a->modeA_hit) {strMode[2] = 'a';}
if (a->modeC_hit) {strMode[3] = 'c';}
if (trackDataValid(&a->position_valid)) {
snprintf(strLat, 8,"%7.03f", a->lat);
@ -184,6 +176,37 @@ void interactiveShowData(void) {
}
a = a->next;
}
if (!Modes.interactive_rtl1090 && Modes.mode_ac) {
for (unsigned i = 1; i < 4096 && count < Modes.interactive_rows; ++i) {
if (modeAC_match[i] || modeAC_count[i] < 100)
continue;
char strMode[5] = " A ";
char strFl[7] = " ";
unsigned modeA = indexToModeA(i);
int modeC = modeAToModeC(modeA);
if (modeC != INVALID_ALTITUDE) {
strMode[3] = 'C';
snprintf(strFl, 7, "%5d ", convert_altitude(modeC * 100));
}
printf("%7s %-4s %04x %-8s %6s %3s %3s %7s %8s %5s %5d %2s\n",
"", /* address */
strMode, /* mode */
modeA, /* squawk */
"", /* callsign */
strFl, /* altitude */
"", /* gs */
"", /* heading */
"", /* lat */
"", /* lon */
"", /* signal */
modeAC_count[i], /* messages */
""); /* seen */
count++;
}
}
}
//