ENH: coordSetWriter - brought across field scaling and offsets from surface writers

Example:

    formatOptions
    {
        <writer>
        {
            // Apply offsets to field values
            fieldLevel
            {
                T   273.15; // Convert from K to C by subtracting 273.15
            }

            // Note: scale applied after application of field level
            fieldScale
            {
                p   0.001;  // Convert pressure from Pa to kPa by scaling by 0.001
            }
        }
    }

src/meshTools/coordSet/writers/common/coordSetWriter.C

@@ -117,7 +117,12 @@ Foam::coordSetWriter::coordSetWriter()
     verbose_(false),
     nFields_(0),
     currTime_(),
-    outputPath_()
+    outputPath_(),
+    geometryScale_(1),
+    geometryCentre_(Zero),
+    geometryTransform_(),
+    fieldLevel_(),
+    fieldScale_()
 {}
 
 
@@ -126,6 +131,27 @@ Foam::coordSetWriter::coordSetWriter(const dictionary& options)
     coordSetWriter()
 {
     options.readIfPresent("verbose", verbose_);
+
+    geometryScale_ = 1;
+    geometryCentre_ = Zero;
+    geometryTransform_.clear();
+
+    options.readIfPresent("scale", geometryScale_);
+
+    // Optional cartesian coordinate system transform
+    const auto* dictptr = options.findDict("transform", keyType::LITERAL);
+
+    if (dictptr)
+    {
+        dictptr->readIfPresent("rotationCentre", geometryCentre_);
+
+        // 'origin' is optional within sub-dictionary
+        geometryTransform_ =
+            coordSystem::cartesian(*dictptr, IOobjectOption::LAZY_READ);
+    }
+
+    fieldLevel_ = options.subOrEmptyDict("fieldLevel");
+    fieldScale_ = options.subOrEmptyDict("fieldScale");
 }
 
 

src/meshTools/coordSet/writers/common/coordSetWriter.H

@@ -66,6 +66,7 @@ SourceFiles
 #include "UPtrList.H"
 #include "instant.H"
 #include "InfoProxy.H"
+#include "cartesianCS.H"
 #include "runTimeSelectionTables.H"
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
@@ -125,6 +126,21 @@ protected:
         //- The full output directory and file (coords) name
         fileName outputPath_;
 
+        //- Output geometry scaling after rotate/translate
+        scalar geometryScale_;
+
+        //- The centre of rotation (untranslate, translate)
+        point geometryCentre_;
+
+        //- Local coordinate system transformation
+        coordSystem::cartesian geometryTransform_;
+
+        //- Field level to remove (on output)
+        dictionary fieldLevel_;
+
+        //- Field scaling (on output)
+        dictionary fieldScale_;
+
 
     // Buffering
 
@@ -212,6 +228,13 @@ protected:
 
     // Helpers
 
+        template<class Type>
+        tmp<Field<Type>> adjustFieldTemplate
+        (
+            const word& fieldName,
+            const tmp<Field<Type>>& tfield
+        ) const;
+
         //- Repackage field into a UPtrList
         template<class Type>
         static UPtrList<const Field<Type>>

src/meshTools/coordSet/writers/common/coordSetWriterTemplates.C

@@ -25,8 +25,110 @@ License
 
 \*---------------------------------------------------------------------------*/
 
+#include "transformField.H"
+
 // * * * * * * * * * * * * Protected Member Functions  * * * * * * * * * * * //
 
+template<class Type>
+Foam::tmp<Foam::Field<Type>> Foam::coordSetWriter::adjustFieldTemplate
+(
+    const word& fieldName,
+    const tmp<Field<Type>>& tfield
+) const
+{
+    if (verbose_)
+    {
+        Info<< "Writing field " << fieldName;
+    }
+
+    tmp<Field<Type>> tadjusted;
+
+    // Output scaling for the variable, but not for integer types
+    // which are typically ids etc.
+    if (!std::is_integral<Type>::value)
+    {
+        scalar value;
+
+        // Remove *uniform* reference level
+        if
+        (
+            fieldLevel_.readIfPresent(fieldName, value, keyType::REGEX)
+         && !equal(value, 0)
+        )
+        {
+            // Could also detect brackets (...) and read accordingly
+            // or automatically scale by 1/sqrt(nComponents) instead ...
+
+            Type refLevel;
+            for (direction cmpt = 0; cmpt < pTraits<Type>::nComponents; ++cmpt)
+            {
+                setComponent(refLevel, cmpt) = value;
+            }
+
+            if (verbose_)
+            {
+                Info<< " [level " << refLevel << ']';
+            }
+
+            if (!tadjusted)
+            {
+                // Steal or clone
+                tadjusted.reset(tfield.ptr());
+            }
+
+            // Remove offset level
+            tadjusted.ref() -= refLevel;
+        }
+
+        // Apply scaling
+        if
+        (
+            fieldScale_.readIfPresent(fieldName, value, keyType::REGEX)
+         && !equal(value, 1)
+        )
+        {
+            if (verbose_)
+            {
+                Info<< " [scaling " << value << ']';
+            }
+
+            if (!tadjusted)
+            {
+                // Steal or clone
+                tadjusted.reset(tfield.ptr());
+            }
+
+            // Apply scaling
+            tadjusted.ref() *= value;
+        }
+
+        // Rotate fields (vector and non-spherical tensors)
+        if
+        (
+            (pTraits<Type>::rank != 0 && pTraits<Type>::nComponents > 1)
+         && geometryTransform_.valid()
+         && !geometryTransform_.R().is_identity()
+        )
+        {
+            if (!tadjusted)
+            {
+                // Steal or clone
+                tadjusted.reset(tfield.ptr());
+            }
+
+           Foam::transform
+           (
+               tadjusted.ref(),
+               geometryTransform_.R(),
+               tadjusted()
+           );
+        }
+    }
+
+    return (tadjusted ? tadjusted : tfield);
+}
+
+
 template<class Type>
 Foam::UPtrList<const Foam::Field<Type>>
 Foam::coordSetWriter::repackageFields(const Field<Type>& field)