optimization: draw telemetry graph only when necessary

Author: rossengeorgiev

js/app.js

@@ -367,17 +367,23 @@ $(window).ready(function() {
             e.removeClass('active');
             var h = $('#map').height() + $('#telemetry_graph').height();
 
+            plot_open = false;
+
             //analytics
             if(typeof _gaq == 'object') _gaq.push(['_trackEvent', 'UI', 'Collapse', 'Telemetry Graph']);
         } else {
             e.addClass('active');
             var h = $('#map').height() - $('#telemetry_graph').height();
 
+            plot_open = true;
+
             //analytics
             if(typeof _gaq == 'object') _gaq.push(['_trackEvent', 'UI', 'Expand', 'Telemetry Graph']);
         }
         $('#map').stop(null,null).animate({'height': h}, function() {
             if(map) google.maps.event.trigger(map, 'resize');
+
+            if(plot_open && follow_vehicle != -1 && vehicles[follow_vehicle].graph_data_updated) updateGraph(follow_vehicle, true);
         });
     });
 

js/tracker.js

@@ -45,6 +45,7 @@ var ls_receivers = false;
 var ls_pred = false;
 
 var plot = null;
+var plot_open = false;
 
 // weather
 var weatherOverlayId = "nexrad-n0q-900913";
@@ -1245,7 +1246,7 @@ function addPosition(position) {
 }
 
 function updateGraph(idx, reset_selection) {
-    if(!plot) return;
+    if(!plot || !plot_open) return;
 
     if(polyMarker) polyMarker.setPosition(null);
 
@@ -1259,6 +1260,8 @@ function updateGraph(idx, reset_selection) {
 
     // replot graph, with this vehicle data, and this vehicles yaxes config
     plot = $.plot(plot_holder, vehicles[idx].graph_data, $.extend(false, plot_options, {yaxes:vehicles[idx].graph_yaxes}));
+
+    vehicles[idx].graph_data_updated = false;
 }
 
 function graphAddLastPosition(idx) {