From 1bba635ba9c4d1c17da72f8f2c0e9a0c8ff229f2 Mon Sep 17 00:00:00 2001
From: Matthias Wirth <matthias.wirth@gmail.com>
Date: Wed, 9 Dec 2020 10:25:23 +0100
Subject: [PATCH] make sure the map refreshes at least every 2nd data read even
 when panning or zooming also instantly update aircraft positions if the
 visible aircraft count is less than 500

---
 html/script.js | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/html/script.js b/html/script.js
index cf3216c..3073a9d 100644
--- a/html/script.js
+++ b/html/script.js
@@ -99,7 +99,7 @@ let firstFetchDone = false;
 let overrideMapType = null;
 let halloween = false;
 let noRegOnly = false;
-let triggerMapRefresh = false;
+let triggerMapRefresh = 0;
 let firstDraw = true;
 
 let shareLink = '';
@@ -367,7 +367,9 @@ function fetchData() {
             }
 
             if (PendingFetches <= 1) {
-                triggerMapRefresh = true;
+                triggerMapRefresh++;
+                if (TrackedAircraftPositions < 500)
+                    checkRefresh(); // immediately trigger refresh if aircraft count is low enough
             }
             PendingFetches--;
 
@@ -3807,7 +3809,7 @@ function checkMovement() {
         //console.timeEnd("fire!");
     }
 
-    if (noMovement >= 3)
+    if (noMovement >= 3 || triggerMapRefresh > 1)
         checkRefresh();
 
     noMovement++;
@@ -3829,7 +3831,7 @@ function checkRefresh() {
         mapRefresh();
         //console.timeEnd("refreshTable");
 
-        triggerMapRefresh = false;
+        triggerMapRefresh = 0;
     }
 }
 function mapRefresh() {
@@ -3914,9 +3916,6 @@ function changeZoom(init) {
     else
         scaleFactor = markerSmall;
 
-    if (scaleFactor != oldScaleFactor)
-        triggerMapRefresh = true;
-
     // scale markers according to global scaling
     scaleFactor *= Math.pow(1.3, globalScale) * globalScale * iconScale;;