Select the closest edge, not just any nearby (#1922)

lib/network/modules/SelectionHandler.js

@@ -219,15 +219,32 @@ class SelectionHandler {
    * @returns {undefined}
    */
   getEdgeAt(pointer, returnEdge = true) {
-    let positionObject = this._pointerToPositionObject(pointer);
-    let overlappingEdges = this._getAllEdgesOverlappingWith(positionObject);
-
-    if (overlappingEdges.length > 0) {
+    // Iterate over edges, pick closest within 10
+    var canvasPos = this.canvas.DOMtoCanvas(pointer);
+    var mindist = 10;
+    var overlappingEdge = null;
+    var edges = this.body.edges;
+    for (var i = 0; i < this.body.edgeIndices.length; i++) {
+      var edgeId = this.body.edgeIndices[i];
+      var edge = edges[edgeId];
+      if (edge.connected) {
+        var xFrom = edge.from.x;
+        var yFrom = edge.from.y;
+        var xTo = edge.to.x;
+        var yTo = edge.to.y;
+        var dist = edge.edgeType.getDistanceToEdge(xFrom, yFrom, xTo, yTo, canvasPos.x, canvasPos.y);
+        if(dist < mindist){
+          overlappingEdge = edgeId;
+          mindist = dist;
+        }
+      }
+    }
+    if (overlappingEdge) {
       if (returnEdge === true) {
-        return this.body.edges[overlappingEdges[overlappingEdges.length - 1]];
+        return this.body.edges[overlappingEdge];
       }
       else {
-        return overlappingEdges[overlappingEdges.length - 1];
+        return overlappingEdge;
       }
     }
     else {