tweak greatcircle readme

README.md

@@ -134,7 +134,7 @@ If the payload also includes a property `fit:true` the map will zoom to fit the
 Finally if a **greatcircle** property is set containing an array of two coordinates then an arc
 following the great circle between the two co-ordinates is plotted.
 
-    msg.payload = {name:"GC1", greatcircle:[ [51.464,0], [25.76,-80.18] ] }
+    msg.payload = {name:"GC1", color:"#ff00ff", greatcircle:[ [51.464,0], [25.76,-80.18] ] }
 
 There are extra optional properties you can specify - see Options below.
 

worldmap/worldmap.js

@@ -1446,7 +1446,7 @@ function setMarker(data) {
     }
     if (data.hasOwnProperty("greatcircle") && Array.isArray(data.greatcircle) && data.greatcircle.length === 2) {
         delete opt.fill;
-        opt.vertices = 500;
+        opt.vertices = opt.vertices || 100;
         if (!data.hasOwnProperty("weight")) { opt.weight = 3; }    //Standard settings different for lines
         if (!data.hasOwnProperty("opacity")) { opt.opacity = 0.8; }
         var greatc = L.Polyline.Arc(data.greatcircle[0], data.greatcircle[1], opt);