ENH: improved handling of 'unresolved' surface intersections (issue #450)

- the heuristic for matching unresolved intersections is a relatively
  simple matching scheme that seems to be more robust than attempting to walk
  the geometry or the cuts.

- avoid false positives for self intersection

applications/test/surfaceIntersection/Make/options

 EXE_INC = \
-    -I$(LIB_SRC)/finiteVolume/lnInclude \
-    -I$(LIB_SRC)/edgeMesh/lnInclude \
     -I$(LIB_SRC)/meshTools/lnInclude \
+    -I$(LIB_SRC)/surfMesh/lnInclude \
     -I$(LIB_SRC)/triSurface/lnInclude
 
 EXE_LIBS = \
-    -lfiniteVolume \
-    -lmeshTools -ledgeMesh
+    -lmeshTools

applications/test/surfaceIntersection/Test-surfaceIntersection.C

@@ -34,7 +34,7 @@ Description
 #include "triSurface.H"
 #include "triSurfaceMesh.H"
 #include "surfaceIntersection.H"
-#include "OFstream.H"
+#include "OBJstream.H"
 
 using namespace Foam;
 
@@ -172,7 +172,7 @@ int main(int argc, char *argv[])
     {
         Info<< "surf1-cuts: " << cuts.surf1EdgeCuts() << nl
             << "surf2-cuts: " << cuts.surf2EdgeCuts() << nl
-            << "face-pairs: " << cuts.facePairToEdge() << nl
+            << "face-pairs: " << cuts.facePairToEdgeId() << nl
             << "edges: " << cuts.cutEdges() << nl;
     }
 
@@ -198,7 +198,7 @@ int main(int argc, char *argv[])
         {
             Info<< "surf1-cuts: " << cuts.surf1EdgeCuts() << nl
                 << "surf2-cuts: " << cuts.surf2EdgeCuts() << nl
-                << "face-pairs: " << cuts.facePairToEdge() << nl
+                << "face-pairs: " << cuts.facePairToEdgeId() << nl
                 << "edges: " << cuts.cutEdges() << nl;
         }
     }
@@ -209,20 +209,7 @@ int main(int argc, char *argv[])
     if (points.size() || edges.size())
     {
         Info<<"write to " << outputFile << nl;
-
-        OFstream os(outputFile);
-
-        forAll(points, pointi)
-        {
-            const point& pt = points[pointi];
-            os << "v " << pt.x() << ' ' << pt.y() << ' ' << pt.z() << nl;
-        }
-
-        forAll(edges, edgei)
-        {
-            const edge& e = edges[edgei];
-            os << "l " << e.start()+1 << ' ' << e.end()+1 << nl;
-        }
+        OBJstream(outputFile).write(edges, points);
     }
 
     Info<< "End\n" << endl;

applications/utilities/surface/surfaceBooleanFeatures/surfaceBooleanFeatures.C

@@ -99,7 +99,7 @@ typedef CGAL::AABB_face_graph_triangle_primitive
 typedef CGAL::AABB_traits<K, Primitive> Traits;
 typedef CGAL::AABB_tree<Traits> Tree;
 
-typedef boost::optional<Tree::Intersection_and_primitive_id<Segment>::Type >
+typedef boost::optional<Tree::Intersection_and_primitive_id<Segment>::Type>
 Segment_intersection;
 
 #endif // NO_CGAL
@@ -477,7 +477,6 @@ label dupNonManifoldPoints(triSurface& s, labelList& pointMap)
     List<labelledTri> newFaces(s);
     label nNonManifold = 0;
 
-
     forAll(pf, pointI)
     {
         const labelList& pFaces = pf[pointI];
@@ -1257,10 +1256,10 @@ autoPtr<extendedFeatureEdgeMesh> createEdgeMesh
     const triSurface& s1 = surf1;
     const triSurface& s2 = surf2;
 
-    forAllConstIter(labelPairLookup, inter.facePairToEdge(), iter)
+    forAllConstIters(inter.facePairToEdgeId(), iter)
     {
-        const label& cutEdgeI = iter();
         const labelPair& facePair = iter.key();
+        const label cutEdgeI = iter.object();
 
         const edge& fE = inter.cutEdges()[cutEdgeI];
 

applications/utilities/surface/surfaceFeatureExtract/extractionMethod/surfaceFeaturesExtraction.C

@@ -73,7 +73,7 @@ Foam::surfaceFeaturesExtraction::method::New
     dictionaryConstructorTable::iterator cstrIter =
         dictionaryConstructorTablePtr_->find(methodName);
 
-    if (cstrIter == dictionaryConstructorTablePtr_->end())
+    if (!cstrIter.found())
     {
         FatalIOErrorInFunction
         (

applications/utilities/surface/surfaceFeatureExtract/surfaceFeatureExtract.C

@@ -84,6 +84,8 @@ int main(int argc, char *argv[])
 
     forAllConstIter(dictionary, dict, iter)
     {
+        const word& dictName = iter().keyword();
+
         if (!iter().isDict())
         {
             continue;
@@ -106,7 +108,7 @@ int main(int argc, char *argv[])
         const word outputName =
             fileName
             (
-                surfaceDict.lookupOrDefault<word>("output", iter().keyword())
+                surfaceDict.lookupOrDefault<word>("output", dictName)
             ).lessExt();
 
         // The "surfaces" entry is normally optional, but if the sub-dictionary
@@ -115,7 +117,7 @@ int main(int argc, char *argv[])
         // additional switch.
         if
         (
-            iter().keyword() == "surfaces"  // mandatory
+            dictName == "surfaces"  // mandatory
          || surfaceDict.found("surfaces")   // or optional
         )
         {
@@ -123,14 +125,14 @@ int main(int argc, char *argv[])
         }
         else
         {
-            loader.select(iter().keyword());
+            loader.select(dictName);
         }
 
         if (loader.selected().empty())
         {
             FatalErrorInFunction
                 << "No surfaces specified/found for entry: "
-                << iter().keyword() << exit(FatalError);
+                << dictName << exit(FatalError);
         }
         // DebugVar(loader.available());
         // DebugVar(outputName);
@@ -153,7 +155,7 @@ int main(int argc, char *argv[])
         {
             FatalErrorInFunction
                 << "Problem loading surface(s) for entry: "
-                << iter().keyword() << exit(FatalError);
+                << dictName << exit(FatalError);
         }
 
         triSurface surf = surfPtr();

applications/utilities/surface/surfaceFeatureExtract/surfaceFeatureExtractDict

@@ -134,7 +134,7 @@ surface2.nas
 // - If other dictionaries contain a 'surfaces' entry,
 //   it will be taken for the input.
 //
-surfaces
+dummyName
 {
     extractionMethod    extractFromSurface;
 
@@ -169,4 +169,39 @@ surfaces
         writeObj        yes;
 }
 
+
+// Handle single or multiple surfaces
+//
+// - If the dictionary is named 'surfaces', it must also contain a 'surfaces'
+//   entry (wordRe list).
+//
+// - If other dictionaries contain a 'surfaces' entry,
+//   it will be taken for the input.
+//
+surfaces
+{
+    extractionMethod    extractFromNone;
+
+    surfaces            (surface1.stl surface2.nas);
+
+    // Base output name (optional)
+    // output              surfaces;
+
+    // Generate additional features from self-intersect
+    selfIntersection    true;
+
+    // Tolerance for surface intersections
+    tolerance           1e-3;
+
+    extractFromNoneCoeffs
+    {
+        includedAngle   0;
+    }
+
+    // Write options
+
+    // Write features to obj format for postprocessing
+    writeObj        yes;
+}
+
 // ************************************************************************* //

applications/utilities/surface/surfaceSplitNonManifolds/surfaceSplitNonManifolds.C

@@ -129,8 +129,7 @@ void dumpFaces
     const Map<label>& connectedFaces
 )
 {
-    Info<< "Dumping connectedFaces as Lightwave .obj file to " << fName
-        << "\nThis can be visualized with e.g. javaview (www.javaview.de)\n\n";
+    Info<< "Dumping connectedFaces as .obj file to " << fName << nl;
 
     OFstream os(fName);
 

src/meshTools/triSurface/booleanOps/intersectedSurface/edgeSurface.C

@@ -27,56 +27,37 @@ License
 #include "triSurface.H"
 #include "surfaceIntersection.H"
 #include "meshTools.H"
-#include "OFstream.H"
+#include "OBJstream.H"
 
 // * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
 
 namespace Foam
 {
 defineTypeNameAndDebug(edgeSurface, 0);
-}
-
-
-// * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
 
-// Write whole pointField and edges to stream
-void Foam::edgeSurface::writeOBJ
-(
-    const pointField& points,
-    const edgeList& edges,
-    Ostream& os
-)
+// file-scope
+// Write points in obj format
+static void writeObjPoints(const UList<point>& pts, Ostream& os)
 {
-    forAll(points, pointi)
+    forAll(pts, i)
     {
-        const point& pt = points[pointi];
-
-        os << "v " << pt.x() << ' ' << pt.y() << ' ' << pt.z() << endl;
-    }
-    forAll(edges, edgeI)
-    {
-        const edge& e = edges[edgeI];
-
-        os << "l " << e.start()+1 << ' ' << e.end()+1 << endl;
+        const point& pt = pts[i];
+        os << "v " << pt.x() << ' ' << pt.y() << ' ' << pt.z() << nl;
     }
 }
 
 
 // Write whole pointField and selected edges to stream
-void Foam::edgeSurface::writeOBJ
+void writeObjEdges
 (
-    const pointField& points,
+    const UList<point>& points,
     const edgeList& edges,
     const labelList& edgeLabels,
     Ostream& os
 )
 {
-    forAll(points, pointi)
-    {
-        const point& pt = points[pointi];
+    writeObjPoints(points, os);
 
-        os << "v " << pt.x() << ' ' << pt.y() << ' ' << pt.z() << endl;
-    }
     forAll(edgeLabels, i)
     {
         const edge& e = edges[edgeLabels[i]];
@@ -85,6 +66,10 @@ void Foam::edgeSurface::writeOBJ
     }
 }
 
+} // End namespace Foam
+
+
+// * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
 
 // Pointedges in edgeSurface indices only.
 void Foam::edgeSurface::calcPointEdges()
@@ -253,29 +238,16 @@ Foam::edgeSurface::edgeSurface
     }
 
 
-
-
     // Add intersection edges to faceEdges
     // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-    forAllConstIter(labelPairLookup, inter.facePairToEdge(), iter)
+    forAllConstIters(inter.facePairToEdgeId(), iter)
     {
-        // Edge label in intersection
-        const label edgeI = iter();
-
-        // Get the face from the correct surface
-        const FixedList<label, 2>& twoFaces = iter.key();
+        // The faceId from the correct surface
+        const label facei = iter.key()[isFirstSurface ? 0 : 1];
 
-        label facei;
-
-        if (isFirstSurface)
-        {
-            facei = twoFaces[0];
-        }
-        else
-        {
-            facei = twoFaces[1];
-        }
+        // Edge label in intersection
+        const label edgeI = iter.object();
 
         // Store on face-edge addressing. (note: offset edge)
         allFaceEdges[facei].append(edgeI + nSurfaceEdges_);
@@ -312,18 +284,17 @@ Foam::edgeSurface::edgeSurface
                     << " to " << faceFName << endl;
 
                 OFstream fStream(faceFName);
-                writeOBJ(points_, edges_, fEdges, fStream);
+                writeObjEdges(points_, edges_, fEdges, fStream);
             }
         }
 
         Pout<< "edgeSurface : Dumping edges to edges.obj" << endl;
-        OFstream eStream("edges.obj");
-        writeOBJ(points_, edges_, eStream);
+        OBJstream("edges.obj").write(edges_, points_);
 
         Pout<< "edgeSurface : Dumping intersectionEdges to"
             << " intersectionEdges.obj" << endl;
-        OFstream intEdgesStream("intersectionEdges.obj");
 
+        OFstream intEdgesStream("intersectionEdges.obj");
         labelList edgeLabels(edges_.size() - nSurfaceEdges_);
 
         label i = 0;
@@ -332,7 +303,7 @@ Foam::edgeSurface::edgeSurface
             edgeLabels[i++] = edgeI;
         }
 
-        writeOBJ(points_, edges_, edgeLabels, intEdgesStream);
+        writeObjEdges(points_, edges_, edgeLabels, intEdgesStream);
     }
 }
 

src/meshTools/triSurface/booleanOps/intersectedSurface/edgeSurface.H

@@ -93,25 +93,12 @@ private:
         //- From face to our edges_
         labelListList faceEdges_;
 
-
         //- Constructed from above: pointEdges
         labelListList pointEdges_;
 
 
     // Private Member Functions
 
-        //- Dump edges in obj format
-        static void writeOBJ(const pointField&, const edgeList&, Ostream&);
-
-        //- Dump selected edges in obj format
-        static void writeOBJ
-        (
-            const pointField&,
-            const edgeList&,
-            const labelList&,
-            Ostream&
-        );
-
         //- Calculate pointEdges
         void calcPointEdges();
 

src/meshTools/triSurface/booleanOps/surfaceIntersection/surfaceIntersection.H

@@ -50,7 +50,7 @@ Description
         Property       | Description                    | Type   | Default value
         tolerance      | Edge-length tolerance          | scalar | 1e-3
         allowEdgeHits  | Edge-end cuts another edge     | bool   | true
-        avoidDuplicates | Reduce the number of duplicate points    | bool | true
+        snap           | Snap near end-points           | bool   | true
         warnDegenerate | Number of warnings about degenerate edges | label | 0
     \endtable
 
@@ -66,11 +66,11 @@ SourceFiles
 
 #include "DynamicList.H"
 #include "point.H"
-#include "edge.H"
-#include "labelPairHashes.H"
-#include "typeInfo.H"
+#include "edgeHashes.H"
 #include "edgeList.H"
+#include "labelPairHashes.H"
 #include "pointIndexHit.H"
+#include "typeInfo.H"
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
@@ -82,6 +82,14 @@ class triSurfaceSearch;
 class triSurface;
 class edgeIntersections;
 
+
+//- Key is non-commutative pair of labels. Value is commutative pair of labels
+typedef LabelPairMap<edge> labelPairEdgeLookup;
+
+//- Map from edge back to all parents (pairs of faces)
+typedef EdgeMap<labelPairHashSet> edgelabelPairHashLookup;
+
+
 /*---------------------------------------------------------------------------*\
                      Class surfaceIntersection Declaration
 \*---------------------------------------------------------------------------*/
@@ -104,8 +112,8 @@ class surfaceIntersection
         //- Allow edge-ends to cut another edge.
         bool allowEdgeHits_;
 
-        //- Avoid creating duplicate cuts near edge ends
-        bool avoidDuplicates_;
+        //- Snap cut points near edge ends (default: true)
+        bool snapToEnd_;
 
         //- Maximum number of warnings about degenerate edges
         label warnDegenerate_;
@@ -117,27 +125,29 @@ class surfaceIntersection
         //  Reference into cutPoints.
         edgeList cutEdges_;
 
-        //- From face on surf1 and face on surf2 to intersection point
-        //  (label in cutPoints)
-        labelPairLookup facePairToVertex_;
-
         //- From face on surf1 and face on surf2 to intersection edge
+        labelPairEdgeLookup facePairToEdge_;
+
+        //- From face on surf1 and face on surf2 to intersection edgeId
         //  (label in cutEdges)
-        labelPairLookup facePairToEdge_;
+        labelPairLookup facePairToEdgeId_;
 
-        //- Edges on surf1 that are cut. From edge on surf1 to label in cutPoint
-        //  If multiple cuts:sorted from edge.start to edge.end
+        //- Edges on surf1 that are cut.
+        //  From edgeId on surf1 to location in cutPoint
         labelListList surf1EdgeCuts_;
 
-        //- Edges on surf2 that are cut. From edge on surf2 to label in cutPoint
-        //  If multiple cuts:sorted from edge.start to edge.end
+        //- Edges on surf2 that are cut.
+        //  From edgeId on surf2 to location in cutPoint
         labelListList surf2EdgeCuts_;
 
         //- Temporary storage to manage edge-edge self-intersections.
-        HashSet<edge, Hash<edge>> edgeEdgeIntersection_;
+        edgeHashSet edgeEdgeIntersection_;
 
         //- Temporary storage to manage cuts/intersections from the edge ends
-        Map<label> edgeEndAsCut_;
+        Map<label> snappedEnds_;
+
+        //- Temporary storage
+        EdgeMap<label> edgeToId_;
 
 
     // Private Member Functions
@@ -145,17 +155,6 @@ class surfaceIntersection
         //- Adjust intersection options according to the dictionary entries
         void setOptions(const dictionary& dict);
 
-        //- Write points in obj format
-        static void writeOBJ(const List<point>& pts, Ostream& os);
-
-        //- Write points and edges in obj format
-        static void writeOBJ
-        (
-            const List<point>& pts,
-            const List<edge>& edges,
-            Ostream& os
-        );
-
         //- Transfer contents of List<DynamicList<..>> to List<List<..>>
         template<class T>
         static void transfer(List<DynamicList<T>>&,  List<List<T>>&);
@@ -201,8 +200,8 @@ class surfaceIntersection
             const UList<point>& points
         );
 
-        //- Update reference between faceA and faceB. Updates facePairToVertex_
-        //  (first occurrence of face pair) and facePairToEdge_ (second occ.)
+        //- Update reference between faceA and faceB.
+        //  Updates facePairToEdge_ and facePairToEdgeId_ (on the second hit)
         void storeIntersection
         (
             const enum originatingType cutFrom,
@@ -241,6 +240,9 @@ class surfaceIntersection
             List<DynamicList<label>>& surfEdgeCuts
         );
 
+        //- Join disconnected intersection points
+        void joinDisconnected(DynamicList<edge>& allCutEdges);
+
 
 public:
 
@@ -292,7 +294,7 @@ public:
         const edgeList& cutEdges() const;
 
         //- Lookup of pairs of faces to created edges
-        const labelPairLookup& facePairToEdge() const;
+        const labelPairLookup& facePairToEdgeId() const;
 
         //- Access either surf1EdgeCuts (isFirstSurface = true) or
         //  surf2EdgeCuts

src/meshTools/triSurface/booleanOps/surfaceIntersection/surfaceIntersectionFuncs.C

@@ -29,13 +29,14 @@ License
 #include "labelPairHashes.H"
 #include "OFstream.H"
 
-// * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
+// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
 
-void Foam::surfaceIntersection::writeOBJ
-(
-    const List<point>& pts,
-    Ostream& os
-)
+namespace Foam
+{
+
+// file-scope
+// Write points in obj format
+static void writeObjPoints(const UList<point>& pts, Ostream& os)
 {
     forAll(pts, i)
     {
@@ -44,23 +45,10 @@ void Foam::surfaceIntersection::writeOBJ
     }
 }
 
+} // End namespace Foam
 
-void Foam::surfaceIntersection::writeOBJ
-(
-    const List<point>& pts,
-    const List<edge>& edges,
-    Ostream& os
-)
-{
-    writeOBJ(pts, os);
-
-    forAll(edges, i)
-    {
-        const edge& e = edges[i];
 
-        os << "l " << e.start()+1 << ' ' << e.end()+1 << nl;
-    }
-}
+// * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
 
 
 // Get minimum length of all edges connected to point
@@ -254,8 +242,8 @@ void Foam::surfaceIntersection::writeIntersectedEdges
     // Dump all points (surface followed by cutPoints)
     const pointField& pts = surf.localPoints();
 
-    writeOBJ(pts, os);
-    writeOBJ(cutPoints(), os);
+    writeObjPoints(pts, os);
+    writeObjPoints(cutPoints(), os);
 
     forAll(edgeCutVerts, edgeI)
     {