ENH: splitMeshRegions: optionally add regionName to all patches

applications/utilities/mesh/manipulation/splitMeshRegions/splitMeshRegions.C

@@ -55,6 +55,8 @@ Description
     this if you don't mind having disconnected domains in a single region.
     This option requires all cells to be in one (and one only) cellZone.
 
+    - prefixRegion prefixes all normal patches with region name (interface
+    (patches already have region name prefix)
 
     - Should work in parallel.
     cellZones can differ on either side of processor boundaries in which case
@@ -389,6 +391,40 @@ void reorderPatches
 }
 
 
+// Prepend prefix to selected patches.
+void renamePatches
+(
+    fvMesh& mesh,
+    const word& prefix,
+    const labelList& patchesToRename
+)
+{
+    polyBoundaryMesh& polyPatches =
+        const_cast<polyBoundaryMesh&>(mesh.boundaryMesh());
+    forAll(patchesToRename, i)
+    {
+        label patchI = patchesToRename[i];
+        polyPatch& pp = polyPatches[patchI];
+
+        if (isA<coupledPolyPatch>(pp))
+        {
+            WarningIn
+            (
+                "renamePatches(fvMesh&, const word&, const labelList&"
+            )   << "Encountered coupled patch " << pp.name()
+                << ". Will only rename the patch itself,"
+                << " not any referred patches."
+                << " This might have to be done by hand."
+                << endl;
+        }
+
+        pp.name() = prefix + '_' + pp.name();
+    }
+    // Recalculate any demand driven data (e.g. group to name lookup)
+    polyPatches.updateMesh();
+}
+
+
 template<class GeoField>
 void subsetVolFields
 (
@@ -987,6 +1023,7 @@ void createAndWriteRegion
     const fvMesh& mesh,
     const labelList& cellRegion,
     const wordList& regionNames,
+    const bool prefixRegion,
     const labelList& faceToInterface,
     const labelList& interfacePatches,
     const label regionI,
@@ -1017,6 +1054,7 @@ void createAndWriteRegion
         addedPatches.insert(interfacePatches[interfaceI]+1);
     }
 
+
     Info<< "Mapping fields" << endl;
 
     // Map existing fields
@@ -1109,6 +1147,7 @@ void createAndWriteRegion
 
     // Create reordering list to move patches-to-be-deleted to end
     labelList oldToNew(newPatches.size(), -1);
+    DynamicList<label> sharedPatches(newPatches.size());
     label newI = 0;
 
     Info<< "Deleting empty patches" << endl;
@@ -1122,7 +1161,12 @@ void createAndWriteRegion
         {
             if (returnReduce(pp.size(), sumOp<label>()) > 0)
             {
-                oldToNew[patchI] = newI++;
+                oldToNew[patchI] = newI;
+                if (!addedPatches.found(patchI))
+                {
+                    sharedPatches.append(newI);
+                }
+                newI++;
             }
         }
     }
@@ -1152,6 +1196,15 @@ void createAndWriteRegion
     reorderPatches(newMesh(), oldToNew, nNewPatches);
 
 
+    // Rename shared patches with region name
+    if (prefixRegion)
+    {
+        Info<< "Prefixing patches with region name" << endl;
+
+        renamePatches(newMesh(), regionNames[regionI], sharedPatches);
+    }
+
+
     Info<< "Writing new mesh" << endl;
 
     newMesh().setInstance(newMeshInstance);
@@ -1672,6 +1725,11 @@ int main(int argc, char *argv[])
         "useFaceZones",
         "use faceZones to patch inter-region faces instead of single patch"
     );
+    argList::addBoolOption
+    (
+        "prefixRegion",
+        "prefix region name to all patches, not just coupling patches"
+    );
 
     #include "setRootCase.H"
     #include "createTime.H"
@@ -1696,6 +1754,8 @@ int main(int argc, char *argv[])
     const bool detectOnly       = args.optionFound("detectOnly");
     const bool sloppyCellZones  = args.optionFound("sloppyCellZones");
     const bool useFaceZones     = args.optionFound("useFaceZones");
+    const bool prefixRegion     = args.optionFound("prefixRegion");
+
 
     if
     (
@@ -2226,6 +2286,7 @@ int main(int argc, char *argv[])
                 mesh,
                 cellRegion,
                 regionNames,
+                prefixRegion,
                 faceToInterface,
                 interfacePatches,
                 regionI,
@@ -2246,6 +2307,7 @@ int main(int argc, char *argv[])
                 mesh,
                 cellRegion,
                 regionNames,
+                prefixRegion,
                 faceToInterface,
                 interfacePatches,
                 regionI,
@@ -2266,6 +2328,7 @@ int main(int argc, char *argv[])
                     mesh,
                     cellRegion,
                     regionNames,
+                    prefixRegion,
                     faceToInterface,
                     interfacePatches,
                     regionI,