improved edge selection function

examples/network/index.html

@@ -39,6 +39,7 @@
   <p><a href="25_physics_configuration.html">25_physics_configuration.html</a></p>
   <p><a href="26_staticSmoothCurves.html">26_staticSmoothCurves.html</a></p>
   <p><a href="27_world_cup_network.html">27_world_cup_network.html</a></p>
+  <p><a href="28_world_cup_network_performance.html">28_world_cup_network_performance.html</a></p>
   <p><a href="graphviz/graphviz_gallery.html">graphviz_gallery.html</a></p>
 
 </div>

lib/network/Edge.js

@@ -939,42 +939,22 @@ Edge.prototype._getDistanceToEdge = function (x1,y1, x2,y2, x3,y3) { // x3,y3 is
         yVia = via.y;
       }
       var minDistance = 1e9;
-      var i,t,x,y,dx,dy;
+      var distance;
+      var i,t,x,y, lastX, lastY;
       for (i = 0; i < 10; i++) {
         t = 0.1*i;
         x = Math.pow(1-t,2)*x1 + (2*t*(1 - t))*xVia + Math.pow(t,2)*x2;
         y = Math.pow(1-t,2)*y1 + (2*t*(1 - t))*yVia + Math.pow(t,2)*y2;
-        dx = Math.abs(x3-x);
-        dy = Math.abs(y3-y);
-        minDistance = Math.min(minDistance,Math.sqrt(dx*dx + dy*dy));
+        if (i > 0) {
+          distance = this._getDistanceToLine(lastX,lastY,x,y, x3,y3);
+          minDistance = distance < minDistance ? distance : minDistance;
+        }
+        lastX = x; lastY = y;
       }
       return minDistance
     }
     else {
-      var px = x2-x1,
-          py = y2-y1,
-          something = px*px + py*py,
-          u =  ((x3 - x1) * px + (y3 - y1) * py) / something;
-
-      if (u > 1) {
-        u = 1;
-      }
-      else if (u < 0) {
-        u = 0;
-      }
-
-      var x = x1 + u * px,
-          y = y1 + u * py,
-          dx = x - x3,
-          dy = y - y3;
-
-      //# Note: If the actual distance does not matter,
-      //# if you only want to compare what this function
-      //# returns to other results of this function, you
-      //# can just return the squared distance instead
-      //# (i.e. remove the sqrt) to gain a little performance
-
-      return Math.sqrt(dx*dx + dy*dy);
+      return this._getDistanceToLine(x1,y1,x2,y2,x3,y3);
     }
   }
   else {
@@ -998,7 +978,32 @@ Edge.prototype._getDistanceToEdge = function (x1,y1, x2,y2, x3,y3) { // x3,y3 is
   }
 };
 
+Edge.prototype._getDistanceToLine = function(x1,y1,x2,y2,x3,y3) {
+  var px = x2-x1,
+    py = y2-y1,
+    something = px*px + py*py,
+    u =  ((x3 - x1) * px + (y3 - y1) * py) / something;
 
+  if (u > 1) {
+    u = 1;
+  }
+  else if (u < 0) {
+    u = 0;
+  }
+
+  var x = x1 + u * px,
+    y = y1 + u * py,
+    dx = x - x3,
+    dy = y - y3;
+
+  //# Note: If the actual distance does not matter,
+  //# if you only want to compare what this function
+  //# returns to other results of this function, you
+  //# can just return the squared distance instead
+  //# (i.e. remove the sqrt) to gain a little performance
+
+  return Math.sqrt(dx*dx + dy*dy);
+}
 
 /**
  * This allows the zoom level of the network to influence the rendering