From 57d3af8960c4c82ebb1c3e9e5e982201a81bac6b Mon Sep 17 00:00:00 2001
From: Vuko Vukcevic <v.vukcevic@wikki.co.uk>
Date: Fri, 14 Jun 2019 14:36:09 +0200
Subject: [PATCH] Bugfix on creating PrimitivePatch::meshPointsPtr_

We must not enforce the order of points on processor patches when collecting
patch points from faces because this occasionally causes ordering errors on two
sides (e.g. in DLB).
---
 .../PrimitivePatchMeshData.C                  | 43 ++++---------------
 1 file changed, 9 insertions(+), 34 deletions(-)

diff --git a/src/foam/meshes/primitiveMesh/PrimitivePatchTemplate/PrimitivePatchMeshData.C b/src/foam/meshes/primitiveMesh/PrimitivePatchTemplate/PrimitivePatchMeshData.C
index ed7d4364e..b9ad4a1d5 100644
--- a/src/foam/meshes/primitiveMesh/PrimitivePatchTemplate/PrimitivePatchMeshData.C
+++ b/src/foam/meshes/primitiveMesh/PrimitivePatchTemplate/PrimitivePatchMeshData.C
@@ -73,53 +73,28 @@ calcMeshData() const
     // number of faces in the patch
     Map<label> markedPoints(4*this->size());
 
-
     // Important:
     // ~~~~~~~~~~
     // In <= 1.5 the meshPoints would be in increasing order but this gives
     // problems in processor point synchronisation where we have to find out
-    // how the opposite side would have allocated points.
-
-    // Note:
-    // ~~~~~
-    // This is all garbage.  All -ext versions will preserve strong ordering
-    // HJ, 17/Aug/2010
-
-    //- 1.5 code:
-    // If the point is used, set the mark to 1
+    // how the opposite side would have allocated points. We'll use unsorted
+    // version to avoid certain ordering problems
+    dynamicLabelList meshPoints(2*this->size());
     forAll(*this, facei)
     {
         const Face& curPoints = this->operator[](facei);
 
         forAll(curPoints, pointi)
         {
-            markedPoints.insert(curPoints[pointi], -1);
+            if (markedPoints.insert(curPoints[pointi], meshPoints.size()))
+            {
+                meshPoints.append(curPoints[pointi]);
+            }
         }
     }
 
-    // Create the storage and store the meshPoints.  Mesh points are
-    // the ones marked by the usage loop above
-    meshPointsPtr_ = new labelList(markedPoints.toc());
-    labelList& pointPatch = *meshPointsPtr_;
-
-    // Sort the list to preserve compatibility with the old ordering
-    sort(pointPatch);
-
-    // For every point in map give it its label in mesh points
-    forAll(pointPatch, pointi)
-    {
-        markedPoints.find(pointPatch[pointi])() = pointi;
-    }
-
-    forAll(*this, faceI)
-    {
-        const Face& curPoints = this->operator[](faceI);
-
-        forAll (curPoints, pointI)
-        {
-            markedPoints.insert(curPoints[pointI], -1);
-        }
-    }
+    // Transfer to straight list (reuses storage)
+    meshPointsPtr_ = new labelList(meshPoints, true);
 
     // Create local faces. Note that we start off from copy of original face
     // list (even though vertices are overwritten below). This is done so