ENH: patchCloud: return pTraits<Type>::max for unfound points

applications/utilities/postProcessing/sampling/sample/sampleDict

@@ -119,14 +119,17 @@ sets
 
     somePatchPoints
     {
-        // Sample nearest points on selected patches. Use with
-        // interpolations:
+        // Sample nearest points on selected patches. Looks only up to
+        // maxDistance away. Any sampling point not found will get value
+        // pTraits<Type>::max (usually VGREAT)
+        // Use with interpolations:
         // - cell (cell value)
         // - cellPatchConstrained (boundary value)
         // - cellPoint (interpolated boundary value)
         type        patchCloud;
         axis        xyz;
         points      ((0.049 0.099 0.005)(0.051 0.054 0.005));
+        maxDistance 0.1;    // maximum distance to search
         patches     (".*Wall.*");
     }
 );

src/sampling/sampledSet/patchCloud/patchCloudSet.C

@@ -26,13 +26,12 @@ License
 #include "patchCloudSet.H"
 #include "polyMesh.H"
 #include "addToRunTimeSelectionTable.H"
-#include "pointIndexHit.H"
-#include "Tuple2.H"
 #include "treeBoundBox.H"
-#include "indexedOctree.H"
 #include "treeDataFace.H"
 #include "Time.H"
 #include "meshTools.H"
+// For 'nearInfo' helper class only
+#include "directMappedPatchBase.H"
 
 // * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
 
@@ -40,35 +39,6 @@ namespace Foam
 {
     defineTypeNameAndDebug(patchCloudSet, 0);
     addToRunTimeSelectionTable(sampledSet, patchCloudSet, word);
-
-
-    //- Helper class for finding nearest
-    // Nearest:
-    //  - point+local index
-    //  - sqr(distance)
-    //  - processor
-    typedef Tuple2<pointIndexHit, Tuple2<scalar, label> > nearInfo;
-
-    class nearestEqOp
-    {
-
-    public:
-
-        void operator()(nearInfo& x, const nearInfo& y) const
-        {
-            if (y.first().hit())
-            {
-                if (!x.first().hit())
-                {
-                    x = y;
-                }
-                else if (y.second().first() < x.second().first())
-                {
-                    x = y;
-                }
-            }
-        }
-    };
 }
 
 
@@ -114,7 +84,8 @@ void Foam::patchCloudSet::calcSamples
             patchFaces[sz++] = pp.start()+i;
         }
 
-        const boundBox patchBb(pp.points(), pp.meshPoints());
+        // Do not do reduction.
+        const boundBox patchBb(pp.points(), pp.meshPoints(), false);
 
         bb.min() = min(bb.min(), patchBb.min());
         bb.max() = max(bb.max(), patchBb.max());
@@ -125,6 +96,7 @@ void Foam::patchCloudSet::calcSamples
     // Make bb asymetric just to avoid problems on symmetric meshes
     bb = bb.extend(rndGen, 1E-4);
 
+    // Make sure bb is 3D.
     bb.min() -= point(ROOTVSMALL, ROOTVSMALL, ROOTVSMALL);
     bb.max() += point(ROOTVSMALL, ROOTVSMALL, ROOTVSMALL);
 
@@ -146,7 +118,7 @@ void Foam::patchCloudSet::calcSamples
 
 
     // All the info for nearest. Construct to miss
-    List<nearInfo> nearest(sampleCoords_.size());
+    List<directMappedPatchBase::nearInfo> nearest(sampleCoords_.size());
 
     forAll(sampleCoords_, sampleI)
     {
@@ -155,7 +127,15 @@ void Foam::patchCloudSet::calcSamples
         pointIndexHit& nearInfo = nearest[sampleI].first();
 
         // Find the nearest locally
-        nearInfo = patchTree.findNearest(sample, magSqr(bb.span()));
+        if (patchFaces.size())
+        {
+            nearInfo = patchTree.findNearest(sample, sqr(searchDist_));
+        }
+        else
+        {
+            nearInfo.setMiss();
+        }
+
 
         // Fill in the distance field and the processor field
         if (!nearInfo.hit())
@@ -179,7 +159,7 @@ void Foam::patchCloudSet::calcSamples
 
 
     // Find nearest.
-    Pstream::listCombineGather(nearest, nearestEqOp());
+    Pstream::listCombineGather(nearest, directMappedPatchBase::nearestEqOp());
     Pstream::listCombineScatter(nearest);
 
 
@@ -197,6 +177,8 @@ void Foam::patchCloudSet::calcSamples
         label vertI = 0;
 
         forAll(nearest, i)
+        {
+            if (nearest[i].first().hit())
             {
                 meshTools::writeOBJ(str, sampleCoords_[i]);
                 vertI++;
@@ -205,15 +187,18 @@ void Foam::patchCloudSet::calcSamples
                 str << "l " << vertI-1 << ' ' << vertI << nl;
             }
         }
+    }
 
 
     // Store the sampling locations on the nearest processor
     forAll(nearest, sampleI)
-    {
-        if (nearest[sampleI].second().second() == Pstream::myProcNo())
     {
         const pointIndexHit& nearInfo = nearest[sampleI].first();
 
+        if (nearInfo.hit())
+        {
+            if (nearest[sampleI].second().second() == Pstream::myProcNo())
+            {
                 label faceI = nearInfo.index();
 
                 samplingPts.append(nearInfo.hitPoint());
@@ -223,6 +208,20 @@ void Foam::patchCloudSet::calcSamples
                 samplingCurveDist.append(1.0 * sampleI);
             }
         }
+        else
+        {
+            // No processor found point near enough. Mark with special value
+            // which is intercepted when interpolating
+            if (Pstream::master())
+            {
+                samplingPts.append(sampleCoords_[sampleI]);
+                samplingCells.append(-1);
+                samplingFaces.append(-1);
+                samplingSegments.append(0);
+                samplingCurveDist.append(1.0 * sampleI);
+            }
+        }
+    }
 }
 
 
@@ -270,12 +269,14 @@ Foam::patchCloudSet::patchCloudSet
     meshSearch& searchEngine,
     const word& axis,
     const List<point>& sampleCoords,
-    const labelHashSet& patchSet
+    const labelHashSet& patchSet,
+    const scalar searchDist
 )
 :
     sampledSet(name, mesh, searchEngine, axis),
     sampleCoords_(sampleCoords),
-    patchSet_(patchSet)
+    patchSet_(patchSet),
+    searchDist_(searchDist)
 {
     genSamples();
 
@@ -302,7 +303,8 @@ Foam::patchCloudSet::patchCloudSet
         (
             wordReList(dict.lookup("patches"))
         )
-    )
+    ),
+    searchDist_(readScalar(dict.lookup("maxDistance")))
 {
     genSamples();
 

src/sampling/sampledSet/patchCloud/patchCloudSet.H

@@ -56,10 +56,14 @@ class patchCloudSet
     // Private data
 
         //- Sampling points
-        List<point> sampleCoords_;
+        const List<point> sampleCoords_;
 
         //- Patches to sample
-        labelHashSet patchSet_;
+        const labelHashSet patchSet_;
+
+        //- Maximum distance to look for nearest
+        const scalar searchDist_;
+
 
     // Private Member Functions
 
@@ -93,7 +97,8 @@ public:
             meshSearch& searchEngine,
             const word& axis,
             const List<point>& sampleCoords,
-            const labelHashSet& patchSet
+            const labelHashSet& patchSet,
+            const scalar searchDist
         );
 
         //- Construct from dictionary

src/sampling/sampledSet/sampledSets/sampledSetsTemplates.C

@@ -51,21 +51,29 @@ Foam::sampledSets::volFieldSampler<Type>::volFieldSampler
         const sampledSet& samples = samplers[setI];
 
         values.setSize(samples.size());
-        forAll(samples, samplei)
+        forAll(samples, sampleI)
         {
-            const point& samplePt = samples[samplei];
-            label celli = samples.cells()[samplei];
-            label facei = samples.faces()[samplei];
+            const point& samplePt = samples[sampleI];
+            label cellI = samples.cells()[sampleI];
+            label faceI = samples.faces()[sampleI];
 
-            values[samplei] = interpolator().interpolate
+            if (cellI == -1 && faceI == -1)
+            {
+                // Special condition for illegal sampling points
+                values[sampleI] = pTraits<Type>::max;
+            }
+            else
+            {
+                values[sampleI] = interpolator().interpolate
                 (
                     samplePt,
-                celli,
-                facei
+                    cellI,
+                    faceI
                 );
             }
         }
     }
+}
 
 
 template <class Type>
@@ -84,9 +92,18 @@ Foam::sampledSets::volFieldSampler<Type>::volFieldSampler
         const sampledSet& samples = samplers[setI];
 
         values.setSize(samples.size());
-        forAll(samples, samplei)
+        forAll(samples, sampleI)
         {
-            values[samplei] = field[samples.cells()[samplei]];
+            label cellI = samples.cells()[sampleI];
+
+            if (cellI ==-1)
+            {
+                values[sampleI] = pTraits<Type>::max;
+            }
+            else
+            {
+                values[sampleI] = field[cellI];
+            }
         }
     }
 }