ENH: moved indexedOctree and treeBoundBox from meshTools to OpenFOAM

src/OpenFOAM/algorithms/indexedOctree/indexedOctree.H

@@ -0,0 +1,647 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2004-2011 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/>.
+
+Class
+    Foam::indexedOctree
+
+Description
+    Non-pointer based hierarchical recursive searching
+
+SourceFiles
+    indexedOctree.C
+
+\*---------------------------------------------------------------------------*/
+
+#ifndef indexedOctree_H
+#define indexedOctree_H
+
+#include "treeBoundBox.H"
+#include "pointIndexHit.H"
+#include "FixedList.H"
+#include "Ostream.H"
+#include "HashSet.H"
+#include "labelBits.H"
+#include "PackedList.H"
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+namespace Foam
+{
+
+// Forward declaration of classes
+template<class Type> class indexedOctree;
+template<class Type> Ostream& operator<<(Ostream&, const indexedOctree<Type>&);
+class Istream;
+
+
+/*---------------------------------------------------------------------------*\
+                        Class indexedOctreeName Declaration
+\*---------------------------------------------------------------------------*/
+
+TemplateName(indexedOctree);
+
+
+/*---------------------------------------------------------------------------*\
+                           Class indexedOctree Declaration
+\*---------------------------------------------------------------------------*/
+
+template <class Type>
+class indexedOctree
+:
+    public indexedOctreeName
+{
+public:
+
+    // Data types
+
+        //- volume types
+        enum volumeType
+        {
+            UNKNOWN = 0,
+            MIXED = 1,
+            INSIDE = 2,
+            OUTSIDE = 3
+        };
+
+
+        //- Tree node. Has up pointer and down pointers.
+        class node
+        {
+        public:
+
+            //- Bounding box of this node
+            treeBoundBox bb_;
+
+            //- parent node (index into nodes_ of tree)
+            label parent_;
+
+            //- IDs of the 8 nodes on all sides of the mid point
+            FixedList<labelBits, 8> subNodes_;
+
+            friend Ostream& operator<< (Ostream& os, const node& n)
+            {
+                return os << n.bb_ << token::SPACE
+                    << n.parent_ << token::SPACE << n.subNodes_;
+            }
+
+            friend Istream& operator>> (Istream& is, node& n)
+            {
+                return is >> n.bb_ >> n.parent_ >> n.subNodes_;
+            }
+
+            friend bool operator==(const node& a, const node& b)
+            {
+                return
+                    a.bb_ == b.bb_
+                 && a.parent_ == b.parent_
+                 && a.subNodes_ == b.subNodes_;
+            }
+
+            friend bool operator!=(const node& a, const node& b)
+            {
+                return !(a == b);
+            }
+        };
+
+
+private:
+
+    // Static data
+
+        //- Relative peturbation tolerance. Determines when point is
+        //  considered to be close to face/edge of bb of node.
+        //  The tolerance is relative to the bounding box of the smallest
+        //  node.
+        static scalar perturbTol_;
+
+
+    // Private data
+
+        //- Underlying shapes for geometric queries.
+        const Type shapes_;
+
+        //- List of all nodes
+        List<node> nodes_;
+
+        //- List of all contents (referenced by those nodes that are contents)
+        labelListList contents_;
+
+        //- Per node per octant whether is fully inside/outside/mixed.
+        mutable PackedList<2> nodeTypes_;
+
+    // Private Member Functions
+
+        //- Helper: does bb intersect a sphere around sample? Or is any
+        //  corner point of bb closer than nearestDistSqr to sample.
+        //  (bb is implicitly provided as parent bb + octant)
+        static bool overlaps
+        (
+            const treeBoundBox& parentBb,
+            const direction octant,
+            const scalar nearestDistSqr,
+            const point& sample
+        );
+
+        // Construction
+
+            //- Split list of indices into 8 bins
+            //  according to where they are in relation to mid.
+            void divide
+            (
+                const labelList& indices,
+                const treeBoundBox& bb,
+                labelListList& result
+            ) const;
+
+            //- Subdivide the contents node at position contentI.
+            //  Appends to contents.
+            node divide
+            (
+                const treeBoundBox& bb,
+                DynamicList<labelList>& contents,
+                const label contentI
+            ) const;
+
+            //- Split any contents node with more than minSize elements.
+            void splitNodes
+            (
+                const label minSize,
+                DynamicList<node>& nodes,
+                DynamicList<labelList>& contents
+            ) const;
+
+            static label compactContents
+            (
+                DynamicList<node>& nodes,
+                DynamicList<labelList>& contents,
+                const label compactLevel,
+                const label nodeI,
+                const label level,
+                List<labelList>& compactedContents,
+                label& compactI
+            );
+
+            //- Determine inside/outside per node (mixed if cannot be
+            //  determined). Only valid for closed shapes.
+            volumeType calcVolumeType(const label nodeI) const;
+
+            //- Search cached volume type.
+            volumeType getVolumeType(const label nodeI, const point&) const;
+
+
+        // Query
+
+            //- Find nearest point to line.
+            void findNearest
+            (
+                const label nodeI,
+                const linePointRef& ln,
+
+                treeBoundBox& tightest,
+                label& nearestShapeI,
+                point& linePoint,
+                point& nearestPoint
+            ) const;
+
+            //- Return bbox of octant
+            treeBoundBox subBbox
+            (
+                const label parentNodeI,
+                const direction octant
+            ) const;
+
+            //- Helper: take a point on/close to face of bb and push it
+            //  inside or outside of bb.
+            static point pushPoint
+            (
+                const treeBoundBox&,
+                const point&,
+                const bool pushInside
+            );
+
+            //- Helper: take a point on face of bb and push it
+            //  inside or outside of bb.
+            static point pushPoint
+            (
+                const treeBoundBox&,
+                const direction,
+                const point&,
+                const bool pushInside
+            );
+
+            //- Helper: take point on face(s) of bb and push it away from
+            //  edges of face.
+            static point pushPointIntoFace
+            (
+                const treeBoundBox& bb,
+                const vector& dir,          // end-start
+                const point& pt
+            );
+
+            ////- Push point on multiple faces away from any corner/edge.
+            //static void checkMultipleFaces
+            //(
+            //    const treeBoundBox& bb,
+            //    const vector& dir,          // end-start
+            //    pointIndexHit& faceHitInfo,
+            //    direction& faceID
+            //);
+
+            //- Walk to parent of node+octant.
+            bool walkToParent
+            (
+                const label nodeI,
+                const direction octant,
+
+                label& parentNodeI,
+                label& parentOctant
+            ) const;
+
+            //- Walk tree to neighbouring node. Return false if edge of tree
+            //  hit.
+            bool walkToNeighbour
+            (
+                const point& facePoint,
+                const direction faceID,         // direction to walk in
+                label& nodeI,
+                direction& octant
+            ) const;
+
+            //- Debug: return verbose the bounding box faces
+            static word faceString(const direction faceID);
+
+            //- Traverse a node. If intersects a triangle return first
+            // intersection point.
+            // findAny=true : return any intersection
+            // findAny=false: return nearest (to start) intersection
+            void traverseNode
+            (
+                const bool findAny,
+                const point& treeStart,
+                const vector& treeVec,
+
+                const point& start,
+                const point& end,
+                const label nodeI,
+                const direction octantI,
+
+                pointIndexHit& hitInfo,
+                direction& faceID
+            ) const;
+
+            //- Find any or nearest intersection
+            pointIndexHit findLine
+            (
+                const bool findAny,
+                const point& treeStart,
+                const point& treeEnd,
+                const label startNodeI,
+                const direction startOctantI,
+                const bool verbose = false
+            ) const;
+
+            //- Find any or nearest intersection of line between start and end.
+            pointIndexHit findLine
+            (
+                const bool findAny,
+                const point& start,
+                const point& end
+            ) const;
+
+            //- Find all elements intersecting box.
+            void findBox
+            (
+                const label nodeI,
+                const treeBoundBox& searchBox,
+                labelHashSet& elements
+            ) const;
+
+
+            template <class CompareOp>
+            static void findNear
+            (
+                const scalar nearDist,
+                const bool okOrder,
+                const indexedOctree<Type>& tree1,
+                const labelBits index1,
+                const treeBoundBox& bb1,
+                const indexedOctree<Type>& tree2,
+                const labelBits index2,
+                const treeBoundBox& bb2,
+                CompareOp& cop
+            );
+
+
+        // Other
+
+            //- Count number of elements on this and sublevels
+            label countElements(const labelBits index) const;
+
+            //- Dump node+octant to an obj file
+            void writeOBJ(const label nodeI, const direction octant) const;
+
+            //- From index into contents_ to subNodes_ entry
+            static labelBits contentPlusOctant
+            (
+                const label i,
+                const direction octant
+            )
+            {
+                return labelBits(-i - 1, octant);
+            }
+
+            //- From index into nodes_ to subNodes_ entry
+            static labelBits nodePlusOctant
+            (
+                const label i,
+                const direction octant
+            )
+            {
+                return labelBits(i + 1, octant);
+            }
+
+            //- From empty to subNodes_ entry
+            static labelBits emptyPlusOctant
+            (
+                const direction octant
+            )
+            {
+                return labelBits(0, octant);
+            }
+
+public:
+
+        //- Get the perturbation tolerance
+        static scalar& perturbTol();
+
+
+    // Constructors
+
+        //- Construct null
+        indexedOctree(const Type& shapes);
+
+        //- Construct from components
+        indexedOctree
+        (
+            const Type& shapes,
+            const List<node>& nodes,
+            const labelListList& contents
+        );
+
+        //- Construct from shapes
+        indexedOctree
+        (
+            const Type& shapes,
+            const treeBoundBox& bb,
+            const label maxLevels,          // maximum number of levels
+            const scalar maxLeafRatio,      // how many elements per leaf
+            const scalar maxDuplicity       // in how many leaves is a shape on
+                                            // average
+        );
+
+        //- Construct from Istream
+        indexedOctree(const Type& shapes, Istream& is);
+
+        //- Clone
+        autoPtr<indexedOctree<Type> > clone() const
+        {
+            return autoPtr<indexedOctree<Type> >
+            (
+                new indexedOctree<Type>(*this)
+            );
+        }
+
+    // Member Functions
+
+        // Access
+
+            //- Reference to shape
+            const Type& shapes() const
+            {
+                return shapes_;
+            }
+
+            //- List of all nodes
+            const List<node>& nodes() const
+            {
+                return nodes_;
+            }
+
+            //- List of all contents (referenced by those nodes that are
+            //  contents)
+            const labelListList& contents() const
+            {
+                return contents_;
+            }
+
+            //- Top bounding box
+            const treeBoundBox& bb() const
+            {
+                if (nodes_.empty())
+                {
+                    FatalErrorIn("indexedOctree<Type>::bb() const")
+                        << "Tree is empty" << abort(FatalError);
+                }
+                return nodes_[0].bb_;
+            }
+
+
+        // Conversions for entries in subNodes_.
+
+            static bool isContent(const labelBits i)
+            {
+                return i.val() < 0;
+            }
+
+            static bool isEmpty(const labelBits i)
+            {
+                return i.val() == 0;
+            }
+
+            static bool isNode(const labelBits i)
+            {
+                return i.val() > 0;
+            }
+
+            static label getContent(const labelBits i)
+            {
+                if (!isContent(i))
+                {
+                    FatalErrorIn("getContent(const label)")
+                        << abort(FatalError);
+                }
+                return -i.val()-1;
+            }
+
+            static label getNode(const labelBits i)
+            {
+                if (!isNode(i))
+                {
+                    FatalErrorIn("getNode(const label)")
+                        << abort(FatalError);
+                }
+                return i.val() - 1;
+            }
+
+            static direction getOctant(const labelBits i)
+            {
+                return i.bits();
+            }
+
+
+        // Queries
+
+            //- Calculate nearest point on nearest shape.
+            //  Returns
+            //  - bool : any point found nearer than nearestDistSqr
+            //  - label: index in shapes
+            //  - point: actual nearest point found
+            pointIndexHit findNearest
+            (
+                const point& sample,
+                const scalar nearestDistSqr
+            ) const;
+
+            //- Low level: calculate nearest starting from subnode.
+            void findNearest
+            (
+                const label nodeI,
+                const point&,
+
+                scalar& nearestDistSqr,
+                label& nearestShapeI,
+                point& nearestPoint
+            ) const;
+
+            //- Find nearest to line.
+            //  Returns
+            //  - bool : any point found?
+            //  - label: index in shapes
+            //  - point: actual nearest point found
+            //  sets:
+            //  - linePoint : corresponding nearest point on line
+            pointIndexHit findNearest
+            (
+                const linePointRef& ln,
+                treeBoundBox& tightest,
+                point& linePoint
+            ) const;
+
+            //- Find nearest intersection of line between start and end.
+            pointIndexHit findLine
+            (
+                const point& start,
+                const point& end
+            ) const;
+
+            //- Find any intersection of line between start and end.
+            pointIndexHit findLineAny
+            (
+                const point& start,
+                const point& end
+            ) const;
+
+            //- Find (in no particular order) indices of all shapes inside or
+            //  overlapping bounding box (i.e. all shapes not outside box)
+            labelList findBox(const treeBoundBox& bb) const;
+
+            //- Find deepest node (as parent+octant) containing point. Starts
+            //  off from starting index in nodes_ (use 0 to start from top)
+            //  Use getNode and getOctant to extract info, or call findIndices.
+            labelBits findNode(const label nodeI, const point&) const;
+
+            //- Find shape containing point. Only implemented for certain
+            //  shapes.
+            label findInside(const point&) const;
+
+            //- Find the shape indices that occupy the result of findNode
+            const labelList& findIndices(const point&) const;
+
+            //- Determine type (inside/outside/mixed) for point. unknown if
+            //  cannot be determined (e.g. non-manifold surface)
+            volumeType getVolumeType(const point&) const;
+
+            //- Helper function to return the side. Returns outside if
+            //  outsideNormal&vec >= 0, inside otherwise
+            static volumeType getSide
+            (
+                const vector& outsideNormal,
+                const vector& vec
+            );
+
+            //- Helper: does bb intersect a sphere around sample? Or is any
+            //  corner point of bb closer than nearestDistSqr to sample.
+            static bool overlaps
+            (
+                const point& bbMin,
+                const point& bbMax,
+                const scalar nearestDistSqr,
+                const point& sample
+            );
+
+            //- Find near pairs and apply CompareOp to them.
+            //  tree2 can be *this or different tree.
+            template <class CompareOp>
+            void findNear
+            (
+                const scalar nearDist,
+                const indexedOctree<Type>& tree2,
+                CompareOp& cop
+            ) const;
+
+
+        // Write
+
+            //- Print tree. Either print all indices (printContent = true) or
+            //  just size of contents nodes.
+            void print
+            (
+                prefixOSstream&,
+                const bool printContents,
+                const label
+            ) const;
+
+            bool write(Ostream& os) const;
+
+
+    // IOstream Operators
+
+        friend Ostream& operator<< <Type>(Ostream&, const indexedOctree<Type>&);
+};
+
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+} // End namespace Foam
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+#ifdef NoRepository
+#   include "indexedOctree.C"
+#endif
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+#endif
+
+// ************************************************************************* //

src/OpenFOAM/algorithms/indexedOctree/indexedOctreeName.C

@@ -0,0 +1,32 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2004-2011 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 "indexedOctree.H"
+
+// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
+
+defineTypeNameAndDebug(Foam::indexedOctreeName, 0);
+
+// ************************************************************************* //

src/OpenFOAM/algorithms/indexedOctree/labelBits.H

@@ -0,0 +1,153 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2004-2011 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/>.
+
+Class
+    Foam::labelBits
+
+Description
+    A 29bits label and 3bits direction packed into single label
+
+SourceFiles
+
+\*---------------------------------------------------------------------------*/
+
+#ifndef labelBits_H
+#define labelBits_H
+
+#include "label.H"
+#include "uLabel.H"
+#include "direction.H"
+#include "error.H"
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+namespace Foam
+{
+
+
+/*---------------------------------------------------------------------------*\
+                         Class labelBits Declaration
+\*---------------------------------------------------------------------------*/
+
+class labelBits
+{
+    // Private data
+
+        label data_;
+
+        inline static label pack(const label val, const direction bits)
+        {
+#           ifdef FULLDEBUG
+            if (bits > 7 || (((val<<3)>>3) != val))
+            {
+                FatalErrorIn
+                (
+                    "labelBits::pack(const label, const direction)"
+                )   << "Direction " << bits << " outside range 0..7"
+                    << abort(FatalError);
+            }
+#           endif
+
+            return (val<<3) | bits;
+        }
+
+public:
+
+    // Constructors
+
+        //- Construct null
+        inline labelBits()
+        {}
+
+        //- Construct from components
+        inline labelBits(const label val, const direction bits)
+        :
+             data_(pack(val, bits))
+        {}
+
+        //- Construct from Istream
+        inline labelBits(Istream& is)
+        {
+            is >> data_;
+        }
+
+
+
+    // Member Functions
+
+        inline label val() const
+        {
+            return data_ >> 3;
+        }
+
+        inline direction bits() const
+        {
+            return data_ & 7;
+        }
+
+        inline void setVal(const label val)
+        {
+            data_ = pack(val, bits());
+        }
+
+        inline void setBits(const direction bits)
+        {
+            data_ = pack(val(), bits);
+        }
+
+
+    // Member Operators
+
+        inline friend bool operator==(const labelBits& a, const labelBits& b)
+        {
+            return a.data_ == b.data_;
+        }
+
+        inline friend bool operator!=(const labelBits& a, const labelBits& b)
+        {
+            return !(a == b);
+        }
+
+    // IOstream Operators
+
+        inline friend Istream& operator>>(Istream& is, labelBits& lb)
+        {
+            return is >> lb.data_;
+        }
+
+        inline friend Ostream& operator<<(Ostream& os, const labelBits& lb)
+        {
+            return os << lb.data_;
+        }
+};
+
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+} // End namespace Foam
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+#endif
+
+// ************************************************************************* //

src/OpenFOAM/algorithms/indexedOctree/treeDataCell.C

@@ -0,0 +1,271 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2004-2011 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 "treeDataCell.H"
+#include "indexedOctree.H"
+#include "primitiveMesh.H"
+
+// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
+
+defineTypeNameAndDebug(Foam::treeDataCell, 0);
+
+
+// * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
+
+Foam::treeBoundBox Foam::treeDataCell::calcCellBb(const label cellI) const
+{
+    const cellList& cells = mesh_.cells();
+    const faceList& faces = mesh_.faces();
+    const pointField& points = mesh_.points();
+
+    treeBoundBox cellBb
+    (
+        vector(GREAT, GREAT, GREAT),
+        vector(-GREAT, -GREAT, -GREAT)
+    );
+
+    const cell& cFaces = cells[cellI];
+
+    forAll(cFaces, cFaceI)
+    {
+        const face& f = faces[cFaces[cFaceI]];
+
+        forAll(f, fp)
+        {
+            const point& p = points[f[fp]];
+
+            cellBb.min() = min(cellBb.min(), p);
+            cellBb.max() = max(cellBb.max(), p);
+        }
+    }
+    return cellBb;
+}
+
+
+void Foam::treeDataCell::update()
+{
+    if (cacheBb_)
+    {
+        bbs_.setSize(cellLabels_.size());
+
+        forAll(cellLabels_, i)
+        {
+            bbs_[i] = calcCellBb(cellLabels_[i]);
+        }
+    }
+}
+
+
+// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
+
+Foam::treeDataCell::treeDataCell
+(
+    const bool cacheBb,
+    const primitiveMesh& mesh,
+    const labelUList& cellLabels
+)
+:
+    mesh_(mesh),
+    cellLabels_(cellLabels),
+    cacheBb_(cacheBb)
+{
+    update();
+}
+
+
+Foam::treeDataCell::treeDataCell
+(
+    const bool cacheBb,
+    const primitiveMesh& mesh,
+    const Xfer<labelList>& cellLabels
+)
+:
+    mesh_(mesh),
+    cellLabels_(cellLabels),
+    cacheBb_(cacheBb)
+{
+    update();
+}
+
+
+Foam::treeDataCell::treeDataCell
+(
+    const bool cacheBb,
+    const primitiveMesh& mesh
+)
+:
+    mesh_(mesh),
+    cellLabels_(identity(mesh_.nCells())),
+    cacheBb_(cacheBb)
+{
+    update();
+}
+
+
+// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
+
+Foam::pointField Foam::treeDataCell::points() const
+{
+    pointField cc(cellLabels_.size());
+
+    forAll(cellLabels_, i)
+    {
+        cc[i] = mesh_.cellCentres()[cellLabels_[i]];
+    }
+
+    return cc;
+}
+
+
+// Check if any point on shape is inside cubeBb.
+bool Foam::treeDataCell::overlaps
+(
+    const label index,
+    const treeBoundBox& cubeBb
+) const
+{
+    if (cacheBb_)
+    {
+        return cubeBb.overlaps(bbs_[index]);
+    }
+    else
+    {
+        return cubeBb.overlaps(calcCellBb(cellLabels_[index]));
+    }
+}
+
+
+bool Foam::treeDataCell::contains
+(
+    const label index,
+    const point& sample
+) const
+{
+    return mesh_.pointInCell(sample, cellLabels_[index]);
+}
+
+
+// Calculate nearest point to sample. Updates (if any) nearestDistSqr, minIndex,
+// nearestPoint.
+void Foam::treeDataCell::findNearest
+(
+    const labelUList& indices,
+    const point& sample,
+
+    scalar& nearestDistSqr,
+    label& minIndex,
+    point& nearestPoint
+) const
+{
+    forAll(indices, i)
+    {
+        label index = indices[i];
+        label cellI = cellLabels_[index];
+        scalar distSqr = magSqr(sample - mesh_.cellCentres()[cellI]);
+
+        if (distSqr < nearestDistSqr)
+        {
+            nearestDistSqr = distSqr;
+            minIndex = index;
+            nearestPoint = mesh_.cellCentres()[cellI];
+        }
+    }
+}
+
+
+bool Foam::treeDataCell::intersects
+(
+    const label index,
+    const point& start,
+    const point& end,
+    point& intersectionPoint
+) const
+{
+    // Do quick rejection test
+    if (cacheBb_)
+    {
+        const treeBoundBox& cellBb = bbs_[index];
+
+        if ((cellBb.posBits(start) & cellBb.posBits(end)) != 0)
+        {
+            // start and end in same block outside of cellBb.
+            return false;
+        }
+    }
+    else
+    {
+        const treeBoundBox cellBb = calcCellBb(cellLabels_[index]);
+
+        if ((cellBb.posBits(start) & cellBb.posBits(end)) != 0)
+        {
+            // start and end in same block outside of cellBb.
+            return false;
+        }
+    }
+
+
+    // Do intersection with all faces of cell
+    // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+    // Disable picking up intersections behind us.
+    scalar oldTol = intersection::setPlanarTol(0.0);
+
+    const cell& cFaces = mesh_.cells()[cellLabels_[index]];
+
+    const vector dir(end - start);
+    scalar minDistSqr = magSqr(dir);
+    bool hasMin = false;
+
+    forAll(cFaces, i)
+    {
+        const face& f = mesh_.faces()[cFaces[i]];
+
+        pointHit inter = f.ray
+        (
+            start,
+            dir,
+            mesh_.points(),
+            intersection::HALF_RAY
+        );
+
+        if (inter.hit() && sqr(inter.distance()) <= minDistSqr)
+        {
+            // Note: no extra test on whether intersection is in front of us
+            // since using half_ray AND zero tolerance. (note that tolerance
+            // is used to look behind us)
+            minDistSqr = sqr(inter.distance());
+            intersectionPoint = inter.hitPoint();
+            hasMin = true;
+        }
+    }
+
+    // Restore picking tolerance
+    intersection::setPlanarTol(oldTol);
+
+    return hasMin;
+}
+
+
+// ************************************************************************* //

src/OpenFOAM/algorithms/indexedOctree/treeDataCell.H

@@ -0,0 +1,217 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2004-2011 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/>.
+
+Class
+    Foam::treeDataCell
+
+Description
+    Encapsulation of data needed to search in/for cells. Used to find the
+    cell containing a point (e.g. cell-cell mapping).
+
+SourceFiles
+    treeDataCell.C
+
+\*---------------------------------------------------------------------------*/
+
+#ifndef treeDataCell_H
+#define treeDataCell_H
+
+#include "treeBoundBoxList.H"
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+namespace Foam
+{
+
+// Forward declaration of classes
+class primitiveMesh;
+template<class Type> class indexedOctree;
+
+/*---------------------------------------------------------------------------*\
+                        Class treeDataCell Declaration
+\*---------------------------------------------------------------------------*/
+
+class treeDataCell
+{
+    // Private data
+
+        const primitiveMesh& mesh_;
+
+        //- Subset of cells to work on
+        const labelList cellLabels_;
+
+        //- Whether to precalculate and store cell bounding box
+        const bool cacheBb_;
+
+        //- cell bounding boxes (valid only if cacheBb_)
+        treeBoundBoxList bbs_;
+
+
+    // Private Member Functions
+
+        //- Calculate cell bounding box
+        treeBoundBox calcCellBb(const label cellI) const;
+
+        //- Initialise all member data
+        void update();
+
+public:
+
+    // Declare name of the class and its debug switch
+    ClassName("treeDataCell");
+
+
+    // Constructors
+
+        //- Construct from mesh and subset of cells.
+        treeDataCell
+        (
+            const bool cacheBb,
+            const primitiveMesh&,
+            const labelUList&
+        );
+
+        //- Construct from mesh and subset of cells, transferring contents
+        treeDataCell
+        (
+            const bool cacheBb,
+            const primitiveMesh&,
+            const Xfer<labelList>&
+        );
+
+        //- Construct from mesh. Uses all cells in mesh.
+        treeDataCell(const bool cacheBb, const primitiveMesh&);
+
+
+    // Member Functions
+
+        // Access
+
+            inline const labelList& cellLabels() const
+            {
+                return cellLabels_;
+            }
+
+            inline const primitiveMesh& mesh() const
+            {
+                return mesh_;
+            }
+
+
+            inline label size() const
+            {
+                return cellLabels_.size();
+            }
+
+            //- Get representative point cloud for all shapes inside
+            //  (one point per shape)
+            pointField points() const;
+
+
+        // Search
+
+            //- Get type (inside,outside,mixed,unknown) of point w.r.t. surface.
+            //  Only makes sense for closed surfaces.
+            label getVolumeType
+            (
+                const indexedOctree<treeDataCell>&,
+                const point&
+            ) const
+            {
+                notImplemented
+                (
+                    "treeDataCell::getVolumeType"
+                    "(const indexedOctree<treeDataCell>&, const point&)"
+                );
+                return -1;
+            }
+
+            //- Does (bb of) shape at index overlap bb
+            bool overlaps
+            (
+                const label index,
+                const treeBoundBox& sampleBb
+            ) const;
+
+            //- Does shape at index contain sample
+            bool contains
+            (
+                const label index,
+                const point& sample
+            ) const;
+
+            //- Calculates nearest (to sample) point in shape.
+            //  Returns actual point and distance (squared)
+            void findNearest
+            (
+                const labelUList& indices,
+                const point& sample,
+
+                scalar& nearestDistSqr,
+                label& nearestIndex,
+                point& nearestPoint
+            ) const;
+
+            //- Calculates nearest (to line) point in shape.
+            //  Returns point and distance (squared)
+            void findNearest
+            (
+                const labelUList& indices,
+                const linePointRef& ln,
+
+                treeBoundBox& tightest,
+                label& minIndex,
+                point& linePoint,
+                point& nearestPoint
+            ) const
+            {
+                notImplemented
+                (
+                    "treeDataCell::findNearest"
+                    "(const labelUList&, const linePointRef&, ..)"
+                );
+            }
+
+            //- Calculate intersection of shape with ray. Sets result
+            //  accordingly
+            bool intersects
+            (
+                const label index,
+                const point& start,
+                const point& end,
+                point& result
+            ) const;
+
+};
+
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+} // End namespace Foam
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+
+#endif
+
+// ************************************************************************* //