From 74c9cb564c521e2f299d6420ff0b8badb968cb87 Mon Sep 17 00:00:00 2001
From: Steven Davies <github@steev.me.uk>
Date: Sat, 29 Jul 2017 17:52:24 +0100
Subject: [PATCH 1/2] Parallelise the history JSON loads for faster initial
 load times.

As a by-product, for my test server using http/2 this halved the load time against the same code using http/1.1.
---
 public_html/script.js | 29 ++++++++++++++++-------------
 1 file changed, 16 insertions(+), 13 deletions(-)

diff --git a/public_html/script.js b/public_html/script.js
index b505293..4c3d3c3 100644
--- a/public_html/script.js
+++ b/public_html/script.js
@@ -328,24 +328,20 @@ function initialize() {
 
 var CurrentHistoryFetch = null;
 var PositionHistoryBuffer = []
+var HistoryItemsReturned = 0;
 function start_load_history() {
         if (PositionHistorySize > 0 && window.location.hash != '#nohistory') {
                 $("#loader_progress").attr('max',PositionHistorySize);
                 console.log("Starting to load history (" + PositionHistorySize + " items)");
-                load_history_item(0);
-        } else {
-                end_load_history();
+                //Load history items in parallel
+                for (var i = 0; i < PositionHistorySize; i++) {
+                        load_history_item(i);
+                }
         }
 }
 
 function load_history_item(i) {
-        if (i >= PositionHistorySize) {
-                end_load_history();
-                return;
-        }
-
         console.log("Loading history #" + i);
-        $("#loader_progress").attr('value',i);
 
         $.ajax({ url: 'data/history_' + i + '.json',
                  timeout: 5000,
@@ -354,12 +350,19 @@ function load_history_item(i) {
 
                 .done(function(data) {
                         PositionHistoryBuffer.push(data);
-                        load_history_item(i+1);
+                        HistoryItemsReturned++;
+                        $("#loader_progress").attr('value',HistoryItemsReturned);
+                        if (HistoryItemsReturned == PositionHistorySize) {
+                                end_load_history();
+                        }
                 })
 
                 .fail(function(jqxhr, status, error) {
-                        // No more history
-                        end_load_history();
+                        //Doesn't matter if it failed, we'll just be missing a data point
+                        HistoryItemsReturned++;
+                        if (HistoryItemsReturned == PositionHistorySize) {
+                                end_load_history();
+                        }
                 });
 }
 
@@ -378,7 +381,7 @@ function end_load_history() {
                 // Process history
                 for (var h = 0; h < PositionHistoryBuffer.length; ++h) {
                         now = PositionHistoryBuffer[h].now;
-                        console.log("Applying history " + h + "/" + PositionHistoryBuffer.length + " at: " + now);
+                        console.log("Applying history " + h + 1 + "/" + PositionHistoryBuffer.length + " at: " + now);
                         processReceiverUpdate(PositionHistoryBuffer[h]);
 
                         // update track

From 14bbf0923094f14d82c6ddabe0432e0f6160f952 Mon Sep 17 00:00:00 2001
From: Steven Davies <github@steev.me.uk>
Date: Sat, 29 Jul 2017 19:18:56 +0100
Subject: [PATCH 2/2] Fix string concatenation to be addition

---
 public_html/script.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/public_html/script.js b/public_html/script.js
index 4c3d3c3..c9511b0 100644
--- a/public_html/script.js
+++ b/public_html/script.js
@@ -381,7 +381,7 @@ function end_load_history() {
                 // Process history
                 for (var h = 0; h < PositionHistoryBuffer.length; ++h) {
                         now = PositionHistoryBuffer[h].now;
-                        console.log("Applying history " + h + 1 + "/" + PositionHistoryBuffer.length + " at: " + now);
+                        console.log("Applying history " + (h + 1) + "/" + PositionHistoryBuffer.length + " at: " + now);
                         processReceiverUpdate(PositionHistoryBuffer[h]);
 
                         // update track