From bc79b89c5eab65d657e0ca101e0307b5bf41e4b9 Mon Sep 17 00:00:00 2001
From: ahocevar <andreas.hocevar@gmail.com>
Date: Thu, 6 Mar 2014 17:51:07 +0100
Subject: [PATCH] Limit shared segment editing

To avoid surprises, we enable shared segment editing only on
segments that have the same vertex coordinates.
---
 src/ol/interaction/modifyinteraction.js | 21 +++++++++++++--------
 1 file changed, 13 insertions(+), 8 deletions(-)

diff --git a/src/ol/interaction/modifyinteraction.js b/src/ol/interaction/modifyinteraction.js
index 532b797ff7..6296fc8748 100644
--- a/src/ol/interaction/modifyinteraction.js
+++ b/src/ol/interaction/modifyinteraction.js
@@ -510,26 +510,31 @@ ol.interaction.Modify.prototype.handleMouseAtPixel_ = function(pixel, map) {
   if (nodes.length > 0) {
     nodes.sort(sortByDistance);
     var node = nodes[0];
-    var segment = node.segment; // the closest segment
-    var vertex = (ol.coordinate.closestOnSegment(pixelCoordinate, segment));
+    var closestSegment = node.segment;
+    var vertex = (ol.coordinate.closestOnSegment(pixelCoordinate,
+        closestSegment));
     var vertexPixel = map.getPixelFromCoordinate(vertex);
     if (Math.sqrt(ol.coordinate.squaredDistance(pixel, vertexPixel)) <=
         this.pixelTolerance_) {
-      var pixel1 = map.getPixelFromCoordinate(segment[0]);
-      var pixel2 = map.getPixelFromCoordinate(segment[1]);
+      var pixel1 = map.getPixelFromCoordinate(closestSegment[0]);
+      var pixel2 = map.getPixelFromCoordinate(closestSegment[1]);
       var squaredDist1 = ol.coordinate.squaredDistance(vertexPixel, pixel1);
       var squaredDist2 = ol.coordinate.squaredDistance(vertexPixel, pixel2);
       var dist = Math.sqrt(Math.min(squaredDist1, squaredDist2));
       if (dist <= 10) {
-        vertex = squaredDist1 > squaredDist2 ? segment[1] : segment[0];
+        vertex = squaredDist1 > squaredDist2 ?
+            closestSegment[1] : closestSegment[0];
       }
       this.createOrUpdateVertexFeature_(vertex);
       var vertexSegments = {};
-      vertexSegments[goog.getUid(segment)] = true;
+      vertexSegments[goog.getUid(closestSegment)] = true;
+      var segment;
       for (var i = 1, ii = nodes.length; i < ii; ++i) {
         segment = nodes[i].segment;
-        if (ol.coordinate.equals(vertex,
-            ol.coordinate.closestOnSegment(pixelCoordinate, segment))) {
+        if ((ol.coordinate.equals(closestSegment[0], segment[0]) &&
+            ol.coordinate.equals(closestSegment[1], segment[1]) ||
+            (ol.coordinate.equals(closestSegment[0], segment[1]) &&
+            ol.coordinate.equals(closestSegment[1], segment[0])))) {
           vertexSegments[goog.getUid(segment)] = true;
         } else {
           break;