ENH: surface writers now track their own write status

- instead of deciding beforehand if a surface format requires a separate
  geometry file (or if a geometry file should be written if no fields were
  written) now determine afterwards if something was written.

  This improves the overall reliability (consistency) and is more
  convenient for the caller as well.

src/sampling/sampledSurface/sampledSurfaces/sampledSurfaces.C

@@ -536,6 +536,7 @@ bool Foam::sampledSurfaces::performAction(unsigned request)
     // Only seems to be needed for VTK legacy
     countFields();
 
+
     // Update writers
 
     forAll(*this, surfi)
@@ -544,7 +545,6 @@ bool Foam::sampledSurfaces::performAction(unsigned request)
 
         if (((request & actions_[surfi]) & ACTION_WRITE) && nFaces_[surfi])
         {
-            // Output writers
             surfaceWriter& outWriter = writers_[surfi];
 
             if (outWriter.needsUpdate())
@@ -556,24 +556,14 @@ bool Foam::sampledSurfaces::performAction(unsigned request)
 
             outWriter.beginTime(obr_.time());
 
-
+            // Write original ids
-            // Write geometry if no fields would otherwise be written
-            if (!outWriter.nFields() || outWriter.separateGeometry())
-            {
-                outWriter.write();
-                continue;
-            }
-
-            // Write original ids - as label or scalar field
-
-            const word fieldName("Ids");
             if (s.hasFaceIds() && !s.interpolate())
             {
                 writeSurface
                 (
                     outWriter,
                     Field<label>(s.originalIds()),
-                    fieldName
+                    "Ids"
                 );
             }
         }
@@ -610,8 +600,16 @@ bool Foam::sampledSurfaces::performAction(unsigned request)
     // Finish this time step
     forAll(writers_, surfi)
     {
-        if ((request & actions_[surfi]) & ACTION_WRITE)
+        if (((request & actions_[surfi]) & ACTION_WRITE) && nFaces_[surfi])
         {
+            // Write geometry if no fields were written so that we still
+            // can have something to look at
+
+            if (!writers_[surfi].wroteData())
+            {
+                writers_[surfi].write();
+            }
+
             writers_[surfi].endTime();
         }
     }

src/sampling/sampledSurface/sampledSurfaces/sampledSurfaces.H

@@ -352,19 +352,19 @@ public:
         void verbose(const bool verbosity = true);
 
         //- Read the sampledSurfaces dictionary
-        virtual bool read(const dictionary&);
+        virtual bool read(const dictionary& dict);
 
-        //- Execute, currently does nothing
+        //- Sample and store if the sampleOnExecute is enabled.
         virtual bool execute();
 
         //- Sample and write
         virtual bool write();
 
         //- Update for changes of mesh - expires the surfaces
-        virtual void updateMesh(const mapPolyMesh&);
+        virtual void updateMesh(const mapPolyMesh& mpm);
 
         //- Update for mesh point-motion - expires the surfaces
-        virtual void movePoints(const polyMesh&);
+        virtual void movePoints(const polyMesh& mesh);
 
         //- Update for changes of mesh due to readUpdate - expires the surfaces
         virtual void readUpdate(const polyMesh::readUpdateState state);
@@ -372,7 +372,7 @@ public:
         //- Get merge tolerance
         static scalar mergeTol();
 
-        //- Set tolerance (and return old tolerance)
+        //- Set tolerance and return old tolerance
         static scalar mergeTol(const scalar tol);
 };
 

src/surfMesh/writers/boundaryData/boundaryDataSurfaceWriter.C

@@ -159,6 +159,7 @@ Foam::fileName Foam::surfaceWriters::boundaryDataWriter::write()
         //pts.writeEndDivider(os);
     }
 
+    wroteGeom_ = true;
     return surfaceDir;
 }
 
@@ -264,6 +265,7 @@ Foam::fileName Foam::surfaceWriters::boundaryDataWriter::writeTemplate
         OFstream(outputFile)() << tfield();
     }
 
+    wroteGeom_ = true;
     return surfaceDir;
 }
 

src/surfMesh/writers/ensight/ensightSurfaceWriter.C

@@ -185,6 +185,7 @@ Foam::fileName Foam::surfaceWriters::ensightWriter::write()
     // {
     //     return writeUncollated();
     // }
+
     return writeUncollated();
 }
 

src/surfMesh/writers/ensight/ensightSurfaceWriterCollated.C

@@ -34,7 +34,8 @@ Foam::fileName Foam::surfaceWriters::ensightWriter::writeCollated()
     // Geometry:  rootdir/surfaceName/surfaceName.case
     // Geometry:  rootdir/surfaceName/surfaceName.mesh
 
-    return fileName();
+    wroteGeom_ = true;
+    return fileName::null;
 }
 
 
@@ -368,7 +369,7 @@ Foam::fileName Foam::surfaceWriters::ensightWriter::writeCollated
         }
     }
 
-
+    wroteGeom_ = true;
     return outputFile;
 }
 

src/surfMesh/writers/ensight/ensightSurfaceWriterUncollated.C

@@ -97,6 +97,7 @@ Foam::fileName Foam::surfaceWriters::ensightWriter::writeUncollated()
         osGeom << ensPart;
     }
 
+    wroteGeom_ = true;
     return outputFile;
 }
 
@@ -245,6 +246,7 @@ Foam::fileName Foam::surfaceWriters::ensightWriter::writeUncollated
         }
     }
 
+    wroteGeom_ = true;
     return outputFile;
 }
 

src/surfMesh/writers/foam/foamSurfaceWriter.C

@@ -142,6 +142,7 @@ Foam::fileName Foam::surfaceWriters::foamWriter::write()
         OFstream(surfaceDir/"faceCentres")() << faceCentres;
     }
 
+    wroteGeom_ = true;
     return surfaceDir;
 }
 
@@ -155,6 +156,12 @@ Foam::fileName Foam::surfaceWriters::foamWriter::writeTemplate
     const Field<Type>& localValues
 )
 {
+    // Separate geometry
+    if (!wroteGeom_)
+    {
+        write();
+    }
+
     checkOpen();
 
     // Geometry should already have been written
@@ -197,6 +204,7 @@ Foam::fileName Foam::surfaceWriters::foamWriter::writeTemplate
         OFstream(outputFile)() << tfield();
     }
 
+    wroteGeom_ = true;
     return outputFile;
 }
 

src/surfMesh/writers/nastran/nastranSurfaceWriter.C

@@ -437,6 +437,7 @@ Foam::fileName Foam::surfaceWriters::nastranWriter::write()
             << "ENDDATA" << nl;
     }
 
+    wroteGeom_ = true;
     return outputFile;
 }
 

src/surfMesh/writers/nastran/nastranSurfaceWriterImpl.C

@@ -255,6 +255,7 @@ Foam::fileName Foam::surfaceWriters::nastranWriter::writeTemplate
             << "ENDDATA" << endl;
     }
 
+    wroteGeom_ = true;
     return outputFile;
 }
 

src/surfMesh/writers/null/nullSurfaceWriter.C

@@ -87,6 +87,12 @@ bool Foam::surfaceWriters::nullWriter::needsUpdate() const
 }
 
 
+bool Foam::surfaceWriters::nullWriter::wroteData() const
+{
+    return true;
+}
+
+
 bool Foam::surfaceWriters::nullWriter::enabled() const
 {
     return false;
@@ -116,6 +122,7 @@ void Foam::surfaceWriters::nullWriter::open(const fileName& outputPath)
 
 Foam::fileName Foam::surfaceWriters::nullWriter::write()
 {
+    wroteGeom_ = true;
     return fileName::null;
 }
 

src/surfMesh/writers/null/nullSurfaceWriter.H

@@ -94,10 +94,13 @@ public:
 
     // Capability
 
-        //- Never needs an update.
+        //- False: never needs an update.
         virtual bool needsUpdate() const;
 
-        //- The null writer is always disabled, which lets the caller
+        //- True: like a /dev/null device.
+        virtual bool wroteData() const;
+
+        //- False: The null writer is never enabled, which lets the caller
         //- skip various (possibly expensive) preparatory operations.
         virtual bool enabled() const;
 

src/surfMesh/writers/proxy/proxySurfaceWriter.C

@@ -135,6 +135,7 @@ Foam::fileName Foam::surfaceWriters::proxyWriter::write()
         );
     }
 
+    wroteGeom_ = true;
     return outputFile;
 }
 

src/surfMesh/writers/raw/rawSurfaceWriter.C

@@ -178,6 +178,7 @@ Foam::fileName Foam::surfaceWriters::rawWriter::write()
         os  << nl;
     }
 
+    wroteGeom_ = true;
     return outputFile;
 }
 

src/surfMesh/writers/raw/rawSurfaceWriterImpl.C

@@ -197,6 +197,7 @@ Foam::fileName Foam::surfaceWriters::rawWriter::writeTemplate
         }
     }
 
+    wroteGeom_ = true;
     return outputFile;
 }
 

src/surfMesh/writers/starcd/starcdSurfaceWriter.C

@@ -145,6 +145,7 @@ Foam::fileName Foam::surfaceWriters::starcdWriter::write()
         ).write(outputFile, "inp");
     }
 
+    wroteGeom_ = true;
     return outputFile;
 }
 
@@ -158,6 +159,12 @@ Foam::fileName Foam::surfaceWriters::starcdWriter::writeTemplate
     const Field<Type>& localValues
 )
 {
+    // Separate geometry
+    if (!wroteGeom_)
+    {
+        write();
+    }
+
     checkOpen();
 
     // Field:  rootdir/<TIME>/<field>_surfaceName.usr
@@ -206,6 +213,7 @@ Foam::fileName Foam::surfaceWriters::starcdWriter::writeTemplate
         }
     }
 
+    wroteGeom_ = true;
     return outputFile;
 }
 

src/surfMesh/writers/surfaceWriter.C

@@ -138,6 +138,7 @@ Foam::surfaceWriter::surfaceWriter()
     surfComp_(),
     useComponents_(false),
     upToDate_(false),
+    wroteGeom_(false),
     parallel_(true),
     useTimeDir_(false),
     isPointData_(false),
@@ -244,6 +245,7 @@ void Foam::surfaceWriter::endTime()
 void Foam::surfaceWriter::open(const fileName& outputPath)
 {
     outputPath_ = outputPath;
+    wroteGeom_ = false;
 }
 
 
@@ -302,6 +304,7 @@ void Foam::surfaceWriter::open
 void Foam::surfaceWriter::close()
 {
     outputPath_.clear();
+    wroteGeom_ = false;
 }
 
 
@@ -369,11 +372,18 @@ bool Foam::surfaceWriter::needsUpdate() const
 }
 
 
+bool Foam::surfaceWriter::wroteData() const
+{
+    return wroteGeom_;
+}
+
+
 bool Foam::surfaceWriter::expire()
 {
     const bool changed = upToDate_;
 
     upToDate_ = false;
+    wroteGeom_ = false;
     nFields_ = 0;
     merged_.clear();
 
@@ -443,6 +453,11 @@ bool Foam::surfaceWriter::merge() const
     }
     upToDate_ = true;
 
+    if (changed)
+    {
+        wroteGeom_ = false;
+    }
+
     return changed;
 }
 

src/surfMesh/writers/surfaceWriter.H

@@ -56,10 +56,14 @@ Description
         verbose  | Additional output verbosity             | no  | no
     \endtable
 
+Note
+    For surface formats that require geometry in a separate file,
+    it is the responsibility of the implementation (not the caller)
+    to ensure that this occurs.
+
 SourceFiles
-    sampledWriter.C
+    surfaceWriter.C
-    sampledWriterI.H
+    surfaceWriterI.H
-    sampledWriterImpl.C
 
 \*---------------------------------------------------------------------------*/
 
@@ -83,7 +87,7 @@ SourceFiles
 namespace Foam
 {
 
-// Forward declarations
+// Forward Declarations
 class Time;
 class surfaceWriter;
 
@@ -118,10 +122,13 @@ protected:
         //- The topology/surface is up-to-date?
         mutable bool upToDate_;
 
-        //- Writing in parallel (vai master)
+        //- Track if geometry has been written since the last open
+        mutable bool wroteGeom_;
+
+        //- Writing in parallel (via master)
         bool parallel_;
 
-        //- Writer should do something funny
+        //- Insert additional time sub-directory in the output path
         bool useTimeDir_;
 
         //- Is point vs cell data
@@ -185,13 +192,17 @@ protected:
             const Field<Type>& localValues  //!< Local field values to write
         )
         {
+            if (!wroteGeom_)
+            {
+                return this->write();
+            }
             return fileName::null;
         }
 
 
 public:
 
-    // Public data
+    // Public Data
 
         //- The default merge dimension (1e-8)
         static scalar defaultMergeDim;
@@ -294,6 +305,9 @@ public:
         //- Does the writer need an update (eg, lagging behind surface changes)
         virtual bool needsUpdate() const;
 
+        //- Geometry or fields written since the last open?
+        virtual bool wroteData() const;
+
         //- Mark that surface changed and the writer will need an update,
         //- and set nFields = 0.
         //  May also free up unneeded data.

src/surfMesh/writers/vtk/vtkSurfaceWriter.C

@@ -248,6 +248,7 @@ Foam::fileName Foam::surfaceWriters::vtkWriter::write()
         writer_->writeGeometry();
     }
 
+    wroteGeom_ = true;
     return outputFile;
 }
 
@@ -288,6 +289,7 @@ Foam::fileName Foam::surfaceWriters::vtkWriter::writeTemplate
         writer_->write(fieldName, tfield());
     }
 
+    wroteGeom_ = true;
     return outputFile;
 }