ENH: extended runTimePostProcessing (#1206)

- Extended runTimePostProcessing to include access to "live"
  simulation objects such a geometry patches and sampled surfaces
  stored on the "functionObjectObjects" registry.

- Add 'live' runTimePostProcessing of cloud data.
  Extracts position and fields from the cloud via its objectRegistry writer

- For the "live" simulation objects, there are two new volume filters
  that work directly with the OpenFOAM volume fields:
      * iso-surface
      * cutting planes
  Both use the VTK algorithms directly and support multiple values.
  Eg, can make multiple iso-levels or multiple planes parallel to each
  other.

- When VTK has been compiled with MPI-support, parallel rendering will
  be used.

- Additional title text properties (shadow, italic etc)

- Simplified handling of scalar-bar and visibility switches

- Support multiple text positions. Eg, for adding watermark text.

src/functionObjects/graphics/runTimePostProcessing/geometryCloudTemplates.C

@@ -0,0 +1,168 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2019 OpenCFD Ltd.
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+License
+    This file is part of OpenFOAM.
+
+    OpenFOAM is free software: you can redistribute it and/or modify it
+    under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
+    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+    for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
+
+\*---------------------------------------------------------------------------*/
+
+#include "foamVtkTools.H"
+
+// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
+
+template<class Type>
+bool Foam::functionObjects::runTimePostPro::geometryCloud::addField
+(
+    vtkDataSet* piece,
+    const Field<Type>& fld,
+    const word& fieldName
+) const
+{
+    if (!piece) return false;
+
+    auto vtkfield = Foam::vtk::Tools::convertFieldToVTK<Type>(fieldName, fld);
+
+    // Only has verts
+    piece->GetPointData()->AddArray(vtkfield);
+
+    return true;
+}
+
+
+template<class Type>
+bool Foam::functionObjects::runTimePostPro::geometryCloud::addCloudField
+(
+    vtkMultiPieceDataSet* multiPiece,
+    const IOField<Type>* fldptr,
+    const word& fieldName
+) const
+{
+    if (!multiPiece)
+    {
+        return false;
+    }
+
+    if (!needsCollective())
+    {
+        // Simple case (serial-serial, parallel-parallel)
+
+        return fldptr &&
+            addField<Type>
+            (
+                multiPiece->GetPiece(Pstream::myProcNo()),
+                *fldptr,
+                fieldName
+            );
+    }
+
+
+    // Gather fields
+    const bool ok = returnReduce((fldptr != nullptr), orOp<bool>());
+
+    if (!ok)
+    {
+        return false;
+    }
+
+    if (Pstream::master())
+    {
+        if (fldptr)
+        {
+            // My field data
+            addField<Type>
+            (
+                multiPiece->GetPiece(Pstream::myProcNo()),
+                *fldptr,
+                fieldName
+            );
+        }
+
+        // Receive field data
+        Field<Type> recv;
+
+        for
+        (
+            int slave=Pstream::firstSlave();
+            slave<=Pstream::lastSlave();
+            ++slave
+        )
+        {
+            IPstream fromSlave(Pstream::commsTypes::scheduled, slave);
+
+            recv.clear();
+
+            fromSlave
+                >> recv;
+
+            if (recv.size())
+            {
+                addField<Type>
+                (
+                    multiPiece->GetPiece(slave),
+                    recv,
+                    fieldName
+                );
+            }
+        }
+    }
+    else
+    {
+        // Slave - send field data
+
+        OPstream toMaster
+        (
+            Pstream::commsTypes::scheduled,
+            Pstream::masterNo()
+        );
+
+        if (fldptr)
+        {
+            toMaster
+                << *fldptr;
+        }
+        else
+        {
+            toMaster
+                << List<Type>();
+        }
+    }
+
+    return ok;
+}
+
+
+template<class Type>
+bool Foam::functionObjects::runTimePostPro::geometryCloud::addCloudField
+(
+    vtkMultiPieceDataSet* multiPiece,
+    const regIOobject* ioptr,
+    const word& fieldName
+) const
+{
+    return addCloudField<Type>
+    (
+        multiPiece,
+        dynamic_cast<const IOField<Type>*>(ioptr),
+        fieldName
+    );
+}
+
+
+// ************************************************************************* //