SkyView: Unify stale check for loading the history

When loading the history, the check for stale aircraft tracks is done
differently.
This results in lots of dotted/stale track after opening the web page.
Improve this by using the same 5 second timeout stale criterion to
postions loaded from history. Add an additional check to better detect
stale tracks when loading history positions that are spaced 30 seconds
apart.
This commit is contained in:
Matthias Wirth 2019-07-27 17:50:41 +02:00
parent 5cc04d4ca8
commit 207ca0c401
2 changed files with 17 additions and 6 deletions

View file

@ -136,7 +136,7 @@ PlaneObject.prototype.isFiltered = function() {
// Appends data to the running track so we can get a visual tail on the plane // Appends data to the running track so we can get a visual tail on the plane
// Only useful for a long running browser session. // Only useful for a long running browser session.
PlaneObject.prototype.updateTrack = function(estimate_time) { PlaneObject.prototype.updateTrack = function(receiver_timestamp, last_timestamp) {
if (!this.position) if (!this.position)
return false; return false;
if (this.prev_position && this.position[0] == this.prev_position[0] && this.position[1] == this.prev_position[1]) if (this.prev_position && this.position[0] == this.prev_position[0] && this.position[1] == this.prev_position[1])
@ -172,9 +172,20 @@ PlaneObject.prototype.updateTrack = function(estimate_time) {
} }
var lastseg = this.track_linesegs[this.track_linesegs.length - 1]; var lastseg = this.track_linesegs[this.track_linesegs.length - 1];
var elapsed = (this.last_position_time - prev_time);
// Determine if track data are intermittent/stale
var est_track = (elapsed > estimate_time); // Time difference between two position updates should not be much
// greater than the difference between data inputs
// MLAT data are given some more leeway
var time_difference = (this.last_position_time - prev_time) - (receiver_timestamp - last_timestamp);
var stale_timeout = (this.position_from_mlat ? 30 : 5);
var est_track = (time_difference > stale_timeout);
// Also check if the position was already stale when it was exported by dump1090
// Makes stale check more accurate for history points spaced 30 seconds apart
est_track = est_track || ((receiver_timestamp - this.last_position_time) > stale_timeout);
var ground_track = (this.altitude === "ground"); var ground_track = (this.altitude === "ground");
if (est_track) { if (est_track) {
@ -557,7 +568,7 @@ PlaneObject.prototype.updateTick = function(receiver_timestamp, last_timestamp)
} else { } else {
if (this.position !== null && (this.selected || this.seen_pos < 60)) { if (this.position !== null && (this.selected || this.seen_pos < 60)) {
this.visible = true; this.visible = true;
if (this.updateTrack(receiver_timestamp - last_timestamp + (this.position_from_mlat ? 30 : 5))) { if (this.updateTrack(receiver_timestamp, last_timestamp)) {
this.updateLines(); this.updateLines();
this.updateMarker(true); this.updateMarker(true);
} else { } else {

View file

@ -444,7 +444,7 @@ function end_load_history() {
console.log("Updating tracks at: " + now); console.log("Updating tracks at: " + now);
for (var i = 0; i < PlanesOrdered.length; ++i) { for (var i = 0; i < PlanesOrdered.length; ++i) {
var plane = PlanesOrdered[i]; var plane = PlanesOrdered[i];
plane.updateTrack((now - last) + 1); plane.updateTrack(now, last);
} }
last = now; last = now;