use node_id hash to calculate startAngle for client layer

lib/map/clientlayer.js

@@ -1,8 +1,16 @@
-define(["leaflet"],
-  function (L) {
+define(["leaflet", "jshashes"],
+  function (L, jsHashes) {
+    var MD5 = new jsHashes.MD5()
+
     return L.TileLayer.Canvas.extend({
       setData: function (d) {
         this.data = d
+
+        //pre-calculate start angles
+        this.data.all().forEach(function (d) {
+          var hash = MD5.hex(d.node.nodeinfo.node_id)
+          d.startAngle = (parseInt(hash.substr(0, 2), 16) / 255) * 2 * Math.PI
+        })
         this.redraw()
       },
       drawTile: function (canvas, tilePoint) {
@@ -33,7 +41,6 @@ define(["leaflet"],
         var radius = 3
         var a = 1.2
         var startDistance = 12
-        var startAngle = Math.PI
 
         ctx.beginPath()
         nodes.forEach(function (d) {
@@ -47,6 +54,7 @@ define(["leaflet"],
           p.y -= s.y
 
           var distance = startDistance
+          var startAngle = d.startAngle
           var angle = startAngle
 
           for (var i = 0; i < clients; i++) {