Grid.h

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//
// Copyright (c) DreamWorks Animation LLC
//
// All rights reserved. This software is distributed under the
// Mozilla Public License 2.0 ( http://www.mozilla.org/MPL/2.0/ )
//
// Redistributions of source code must retain the above copyright
// and license notice and the following restrictions and disclaimer.
//
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// its contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
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#ifndef OPENVDB_GRID_HAS_BEEN_INCLUDED
#define OPENVDB_GRID_HAS_BEEN_INCLUDED

#include "Exceptions.h"
#include "MetaMap.h"
#include "Types.h"
#include "io/io.h"
#include "math/Transform.h"
#include "tree/Tree.h"
#include "util/logging.h"
#include "util/Name.h"
#include <cassert>
#include <iostream>
#include <set>
#include <type_traits>
#include <vector>


namespace openvdb {
OPENVDB_USE_VERSION_NAMESPACE
namespace OPENVDB_VERSION_NAME {

using TreeBase = tree::TreeBase;

template<typename> class Grid; // forward declaration


template<typename GridType>
inline typename GridType::Ptr createGrid(const typename GridType::ValueType& background);


template<typename GridType>
inline typename GridType::Ptr createGrid();


template<typename TreePtrType>
inline typename Grid<typename TreePtrType::element_type>::Ptr createGrid(TreePtrType);


template<typename GridType>
typename GridType::Ptr createLevelSet(
    Real voxelSize = 1.0, Real halfWidth = LEVEL_SET_HALF_WIDTH);




class OPENVDB_API GridBase: public MetaMap
{
public:
    using Ptr      = SharedPtr<GridBase>;
    using ConstPtr = SharedPtr<const GridBase>;

    using GridFactory = Ptr (*)();


    ~GridBase() override {}



#if OPENVDB_ABI_VERSION_NUMBER <= 3
    OPENVDB_DEPRECATED virtual GridBase::Ptr copyGrid(CopyPolicy treePolicy = CP_SHARE) const = 0;
#else
    virtual GridBase::Ptr copyGrid() = 0;
    virtual GridBase::ConstPtr copyGrid() const = 0;
    virtual GridBase::Ptr copyGridWithNewTree() const = 0;
#endif
    virtual GridBase::Ptr deepCopyGrid() const = 0;




    static Ptr createGrid(const Name& type);

    static bool isRegistered(const Name &type);

    static void clearRegistry();



    virtual Name type() const = 0;
    virtual Name valueType() const = 0;

    template<typename GridType>
    bool isType() const { return (this->type() == GridType::gridType()); }


    template<typename GridType>
    static typename GridType::Ptr grid(const GridBase::Ptr&);
    template<typename GridType>
    static typename GridType::ConstPtr grid(const GridBase::ConstPtr&);
    template<typename GridType>
    static typename GridType::ConstPtr constGrid(const GridBase::Ptr&);
    template<typename GridType>
    static typename GridType::ConstPtr constGrid(const GridBase::ConstPtr&);


    TreeBase::Ptr baseTreePtr();
    TreeBase::ConstPtr baseTreePtr() const { return this->constBaseTreePtr(); }
    virtual TreeBase::ConstPtr constBaseTreePtr() const = 0;

    TreeBase& baseTree() { return const_cast<TreeBase&>(this->constBaseTree()); }
    const TreeBase& baseTree() const { return this->constBaseTree(); }
    const TreeBase& constBaseTree() const { return *(this->constBaseTreePtr()); }

    virtual void setTree(TreeBase::Ptr) = 0;

    virtual void newTree() = 0;


    virtual bool empty() const = 0;
    virtual void clear() = 0;



    virtual void pruneGrid(float tolerance = 0.0) = 0;

#if OPENVDB_ABI_VERSION_NUMBER >= 3
    void clipGrid(const BBoxd&);

    virtual void clip(const CoordBBox&) = 0;
#endif


    template<typename GridTypeListT, typename OpT> inline bool apply(OpT&) const;
    template<typename GridTypeListT, typename OpT> inline bool apply(OpT&);
    template<typename GridTypeListT, typename OpT> inline bool apply(const OpT&) const;
    template<typename GridTypeListT, typename OpT> inline bool apply(const OpT&);


    std::string getName() const;
    void setName(const std::string&);

    std::string getCreator() const;
    void setCreator(const std::string&);

    bool saveFloatAsHalf() const;
    void setSaveFloatAsHalf(bool);

    GridClass getGridClass() const;
    void setGridClass(GridClass);
    void clearGridClass();


    static std::string gridClassToString(GridClass);
    static std::string gridClassToMenuName(GridClass);
    static GridClass stringToGridClass(const std::string&);


    VecType getVectorType() const;
    void setVectorType(VecType);
    void clearVectorType();


    static std::string vecTypeToString(VecType);
    static std::string vecTypeExamples(VecType);
    static std::string vecTypeDescription(VecType);
    static VecType stringToVecType(const std::string&);


    bool isInWorldSpace() const;
    void setIsInWorldSpace(bool);


    // Standard metadata field names
    // (These fields should normally not be accessed directly, but rather
    // via the accessor methods above, when available.)
    // Note: Visual C++ requires these declarations to be separate statements.
    static const char* const META_GRID_CLASS;
    static const char* const META_GRID_CREATOR;
    static const char* const META_GRID_NAME;
    static const char* const META_SAVE_HALF_FLOAT;
    static const char* const META_IS_LOCAL_SPACE;
    static const char* const META_VECTOR_TYPE;
    static const char* const META_FILE_BBOX_MIN;
    static const char* const META_FILE_BBOX_MAX;
    static const char* const META_FILE_COMPRESSION;
    static const char* const META_FILE_MEM_BYTES;
    static const char* const META_FILE_VOXEL_COUNT;
    static const char* const META_FILE_DELAYED_LOAD;



    virtual Index64 activeVoxelCount() const = 0;

    virtual CoordBBox evalActiveVoxelBoundingBox() const = 0;

    virtual Coord evalActiveVoxelDim() const = 0;

    virtual Index64 memUsage() const = 0;

    void addStatsMetadata();
    MetaMap::Ptr getStatsMetadata() const;




    math::Transform::Ptr transformPtr() { return mTransform; }
    math::Transform::ConstPtr transformPtr() const { return mTransform; }
    math::Transform::ConstPtr constTransformPtr() const { return mTransform; }

    math::Transform& transform() { return *mTransform; }
    const math::Transform& transform() const { return *mTransform; }
    const math::Transform& constTransform() const { return *mTransform; }



    void setTransform(math::Transform::Ptr);

    Vec3d voxelSize() const { return transform().voxelSize(); }
    Vec3d voxelSize(const Vec3d& xyz) const { return transform().voxelSize(xyz); }
    bool hasUniformVoxels() const { return mTransform->hasUniformScale(); }
    Vec3d indexToWorld(const Vec3d& xyz) const { return transform().indexToWorld(xyz); }
    Vec3d indexToWorld(const Coord& ijk) const { return transform().indexToWorld(ijk); }
    Vec3d worldToIndex(const Vec3d& xyz) const { return transform().worldToIndex(xyz); }




    virtual void readTopology(std::istream&) = 0;
    virtual void writeTopology(std::ostream&) const = 0;

    virtual void readBuffers(std::istream&) = 0;
#if OPENVDB_ABI_VERSION_NUMBER >= 3
    virtual void readBuffers(std::istream&, const CoordBBox&) = 0;
    virtual void readNonresidentBuffers() const = 0;
#endif
    virtual void writeBuffers(std::ostream&) const = 0;

    void readTransform(std::istream& is) { transform().read(is); }
    void writeTransform(std::ostream& os) const { transform().write(os); }

    virtual void print(std::ostream& = std::cout, int verboseLevel = 1) const = 0;



protected:
    GridBase(): mTransform(math::Transform::createLinearTransform()) {}

    GridBase(const GridBase& other): MetaMap(other), mTransform(other.mTransform->copy()) {}

#if OPENVDB_ABI_VERSION_NUMBER <= 3
    OPENVDB_DEPRECATED
    GridBase(const GridBase& other, ShallowCopy): MetaMap(other), mTransform(other.mTransform) {}
#else
    GridBase(GridBase& other, ShallowCopy): MetaMap(other), mTransform(other.mTransform) {}
#endif

    static void registerGrid(const Name& type, GridFactory);
    static void unregisterGrid(const Name& type);


private:
    math::Transform::Ptr mTransform;
}; // class GridBase




using GridPtrVec       = std::vector<GridBase::Ptr>;
using GridPtrVecIter   = GridPtrVec::iterator;
using GridPtrVecCIter  = GridPtrVec::const_iterator;
using GridPtrVecPtr    = SharedPtr<GridPtrVec>;

using GridCPtrVec      = std::vector<GridBase::ConstPtr>;
using GridCPtrVecIter  = GridCPtrVec::iterator;
using GridCPtrVecCIter = GridCPtrVec::const_iterator;
using GridCPtrVecPtr   = SharedPtr<GridCPtrVec>;

using GridPtrSet       = std::set<GridBase::Ptr>;
using GridPtrSetIter   = GridPtrSet::iterator;
using GridPtrSetCIter  = GridPtrSet::const_iterator;
using GridPtrSetPtr    = SharedPtr<GridPtrSet>;

using GridCPtrSet      = std::set<GridBase::ConstPtr>;
using GridCPtrSetIter  = GridCPtrSet::iterator;
using GridCPtrSetCIter = GridCPtrSet::const_iterator;
using GridCPtrSetPtr   = SharedPtr<GridCPtrSet>;


struct OPENVDB_API GridNamePred
{
    GridNamePred(const Name& _name): name(_name) {}
    bool operator()(const GridBase::ConstPtr& g) const { return g && g->getName() == name; }
    Name name;
};

template<typename GridPtrContainerT>
inline typename GridPtrContainerT::value_type
findGridByName(const GridPtrContainerT& container, const Name& name)
{
    using GridPtrT = typename GridPtrContainerT::value_type;
    typename GridPtrContainerT::const_iterator it =
        std::find_if(container.begin(), container.end(), GridNamePred(name));
    return (it == container.end() ? GridPtrT() : *it);
}

template<typename KeyT, typename GridPtrT>
inline GridPtrT
findGridByName(const std::map<KeyT, GridPtrT>& container, const Name& name)
{
    using GridPtrMapT = std::map<KeyT, GridPtrT>;
    for (typename GridPtrMapT::const_iterator it = container.begin(), end = container.end();
        it != end; ++it)
    {
        const GridPtrT& grid = it->second;
        if (grid && grid->getName() == name) return grid;
    }
    return GridPtrT();
}




template<typename _TreeType>
class Grid: public GridBase
{
public:
    using Ptr                 = SharedPtr<Grid>;
    using ConstPtr            = SharedPtr<const Grid>;

    using TreeType            = _TreeType;
    using TreePtrType         = typename _TreeType::Ptr;
    using ConstTreePtrType    = typename _TreeType::ConstPtr;
    using ValueType           = typename _TreeType::ValueType;
    using BuildType           = typename _TreeType::BuildType;

    using ValueOnIter         = typename _TreeType::ValueOnIter;
    using ValueOnCIter        = typename _TreeType::ValueOnCIter;
    using ValueOffIter        = typename _TreeType::ValueOffIter;
    using ValueOffCIter       = typename _TreeType::ValueOffCIter;
    using ValueAllIter        = typename _TreeType::ValueAllIter;
    using ValueAllCIter       = typename _TreeType::ValueAllCIter;

    using Accessor            = typename tree::ValueAccessor<_TreeType, true>;
    using ConstAccessor       = typename tree::ValueAccessor<const _TreeType, true>;
    using UnsafeAccessor      = typename tree::ValueAccessor<_TreeType, false>;
    using ConstUnsafeAccessor = typename tree::ValueAccessor<const _TreeType, false>;

    template<typename OtherValueType>
    struct ValueConverter {
        using Type = Grid<typename TreeType::template ValueConverter<OtherValueType>::Type>;
    };

    static Ptr create(const ValueType& background);
    static Ptr create();
    static Ptr create(TreePtrType);
    static Ptr create(const GridBase& other);


    Grid();
    explicit Grid(const ValueType& background);
    explicit Grid(TreePtrType);
    Grid(const Grid&);
    template<typename OtherTreeType>
    explicit Grid(const Grid<OtherTreeType>&);
#if OPENVDB_ABI_VERSION_NUMBER <= 3
    OPENVDB_DEPRECATED Grid(const Grid&, ShallowCopy);
#else
    Grid(Grid&, ShallowCopy);
#endif
    explicit Grid(const GridBase&);

    ~Grid() override {}

    Grid& operator=(const Grid&) = delete;


#if OPENVDB_ABI_VERSION_NUMBER <= 3

    OPENVDB_DEPRECATED Ptr copy(CopyPolicy treePolicy = CP_SHARE) const;
    OPENVDB_DEPRECATED GridBase::Ptr copyGrid(CopyPolicy treePolicy = CP_SHARE) const override;
#else

    Ptr copy();
    ConstPtr copy() const;
    Ptr copyWithNewTree() const;

    GridBase::Ptr copyGrid() override;
    GridBase::ConstPtr copyGrid() const override;
    GridBase::Ptr copyGridWithNewTree() const override;
#endif

    Ptr deepCopy() const { return Ptr(new Grid(*this)); }
    GridBase::Ptr deepCopyGrid() const override { return this->deepCopy(); }



    Name type() const override { return this->gridType(); }
    static Name gridType() { return TreeType::treeType(); }

    Name valueType() const override { return tree().valueType(); }



    const ValueType& background() const { return mTree->background(); }

    bool empty() const override { return tree().empty(); }
    void clear() override { tree().clear(); }

    Accessor getAccessor() { return Accessor(tree()); }
    UnsafeAccessor getUnsafeAccessor() { return UnsafeAccessor(tree()); }
    ConstAccessor getAccessor() const { return ConstAccessor(tree()); }
    ConstAccessor getConstAccessor() const { return ConstAccessor(tree()); }
    ConstUnsafeAccessor getConstUnsafeAccessor() const { return ConstUnsafeAccessor(tree()); }

    ValueOnIter   beginValueOn()       { return tree().beginValueOn(); }
    ValueOnCIter  beginValueOn() const { return tree().cbeginValueOn(); }
    ValueOnCIter cbeginValueOn() const { return tree().cbeginValueOn(); }
    ValueOffIter   beginValueOff()       { return tree().beginValueOff(); }
    ValueOffCIter  beginValueOff() const { return tree().cbeginValueOff(); }
    ValueOffCIter cbeginValueOff() const { return tree().cbeginValueOff(); }
    ValueAllIter   beginValueAll()       { return tree().beginValueAll(); }
    ValueAllCIter  beginValueAll() const { return tree().cbeginValueAll(); }
    ValueAllCIter cbeginValueAll() const { return tree().cbeginValueAll(); }



    void sparseFill(const CoordBBox& bbox, const ValueType& value, bool active = true);
    void fill(const CoordBBox& bbox, const ValueType& value, bool active = true);

    void denseFill(const CoordBBox& bbox, const ValueType& value, bool active = true);

    void pruneGrid(float tolerance = 0.0) override;

#if OPENVDB_ABI_VERSION_NUMBER >= 3
    void clip(const CoordBBox&) override;
#endif

    void merge(Grid& other, MergePolicy policy = MERGE_ACTIVE_STATES);

    template<typename OtherTreeType>
    void topologyUnion(const Grid<OtherTreeType>& other);

    template<typename OtherTreeType>
    void topologyIntersection(const Grid<OtherTreeType>& other);

    template<typename OtherTreeType>
    void topologyDifference(const Grid<OtherTreeType>& other);



    Index64 activeVoxelCount() const override { return tree().activeVoxelCount(); }
    CoordBBox evalActiveVoxelBoundingBox() const override;
    Coord evalActiveVoxelDim() const override;
    void evalMinMax(ValueType& minVal, ValueType& maxVal) const;

    Index64 memUsage() const override { return tree().memUsage(); }




    TreePtrType treePtr() { return mTree; }
    ConstTreePtrType treePtr() const { return mTree; }
    ConstTreePtrType constTreePtr() const { return mTree; }
    TreeBase::ConstPtr constBaseTreePtr() const override { return mTree; }

    TreeType& tree() { return *mTree; }
    const TreeType& tree() const { return *mTree; }
    const TreeType& constTree() const { return *mTree; }



    void setTree(TreeBase::Ptr) override;

    void newTree() override;




    void readTopology(std::istream&) override;
    void writeTopology(std::ostream&) const override;

    void readBuffers(std::istream&) override;
#if OPENVDB_ABI_VERSION_NUMBER >= 3
    void readBuffers(std::istream&, const CoordBBox&) override;
    void readNonresidentBuffers() const override;
#endif
    void writeBuffers(std::ostream&) const override;

    void print(std::ostream& = std::cout, int verboseLevel = 1) const override;


    static inline bool hasMultiPassIO();



    static bool isRegistered() { return GridBase::isRegistered(Grid::gridType()); }
    static void registerGrid()
    {
        GridBase::registerGrid(Grid::gridType(), Grid::factory);
        if (!tree::internal::LeafBufferFlags<ValueType>::IsAtomic) {
            OPENVDB_LOG_WARN("delayed loading of grids of type " << Grid::gridType()
                << " might not be threadsafe on this platform");
        }
    }
    static void unregisterGrid() { GridBase::unregisterGrid(Grid::gridType()); }



private:
    static GridBase::Ptr factory() { return Grid::create(); }

    TreePtrType mTree;
}; // class Grid




template<typename GridType>
inline typename GridType::Ptr
gridPtrCast(const GridBase::Ptr& grid)
{
    return GridBase::grid<GridType>(grid);
}


template<typename GridType>
inline typename GridType::ConstPtr
gridConstPtrCast(const GridBase::ConstPtr& grid)
{
    return GridBase::constGrid<GridType>(grid);
}




template<typename GridType>
inline typename GridType::Ptr
deepCopyTypedGrid(const GridBase::ConstPtr& grid)
{
    if (!grid || !grid->isType<GridType>()) return typename GridType::Ptr();
    return gridPtrCast<GridType>(grid->deepCopyGrid());
}


template<typename GridType>
inline typename GridType::Ptr
deepCopyTypedGrid(const GridBase& grid)
{
    if (!grid.isType<GridType>()) return typename GridType::Ptr();
    return gridPtrCast<GridType>(grid.deepCopyGrid());
}




template<typename _TreeType>
struct TreeAdapter
{
    using TreeType             = _TreeType;
    using NonConstTreeType     = typename std::remove_const<TreeType>::type;
    using TreePtrType          = typename TreeType::Ptr;
    using ConstTreePtrType     = typename TreeType::ConstPtr;
    using NonConstTreePtrType  = typename NonConstTreeType::Ptr;
    using GridType             = Grid<TreeType>;
    using NonConstGridType     = Grid<NonConstTreeType>;
    using GridPtrType          = typename GridType::Ptr;
    using NonConstGridPtrType  = typename NonConstGridType::Ptr;
    using ConstGridPtrType     = typename GridType::ConstPtr;
    using ValueType            = typename TreeType::ValueType;
    using AccessorType         = typename tree::ValueAccessor<TreeType>;
    using ConstAccessorType    = typename tree::ValueAccessor<const TreeType>;
    using NonConstAccessorType = typename tree::ValueAccessor<NonConstTreeType>;

    static TreeType& tree(TreeType& t) { return t; }
    static TreeType& tree(GridType& g) { return g.tree(); }
    static const TreeType& tree(const TreeType& t) { return t; }
    static const TreeType& tree(const GridType& g) { return g.tree(); }
    static const TreeType& constTree(TreeType& t) { return t; }
    static const TreeType& constTree(GridType& g) { return g.constTree(); }
    static const TreeType& constTree(const TreeType& t) { return t; }
    static const TreeType& constTree(const GridType& g) { return g.constTree(); }
};


template<typename _TreeType>
struct TreeAdapter<Grid<_TreeType> >
{
    using TreeType             = _TreeType;
    using NonConstTreeType     = typename std::remove_const<TreeType>::type;
    using TreePtrType          = typename TreeType::Ptr;
    using ConstTreePtrType     = typename TreeType::ConstPtr;
    using NonConstTreePtrType  = typename NonConstTreeType::Ptr;
    using GridType             = Grid<TreeType>;
    using NonConstGridType     = Grid<NonConstTreeType>;
    using GridPtrType          = typename GridType::Ptr;
    using NonConstGridPtrType  = typename NonConstGridType::Ptr;
    using ConstGridPtrType     = typename GridType::ConstPtr;
    using ValueType            = typename TreeType::ValueType;
    using AccessorType         = typename tree::ValueAccessor<TreeType>;
    using ConstAccessorType    = typename tree::ValueAccessor<const TreeType>;
    using NonConstAccessorType = typename tree::ValueAccessor<NonConstTreeType>;

    static TreeType& tree(TreeType& t) { return t; }
    static TreeType& tree(GridType& g) { return g.tree(); }
    static const TreeType& tree(const TreeType& t) { return t; }
    static const TreeType& tree(const GridType& g) { return g.tree(); }
    static const TreeType& constTree(TreeType& t) { return t; }
    static const TreeType& constTree(GridType& g) { return g.constTree(); }
    static const TreeType& constTree(const TreeType& t) { return t; }
    static const TreeType& constTree(const GridType& g) { return g.constTree(); }
};

template<typename _TreeType>
struct TreeAdapter<tree::ValueAccessor<_TreeType> >
{
    using TreeType             = _TreeType;
    using NonConstTreeType     = typename std::remove_const<TreeType>::type;
    using TreePtrType          = typename TreeType::Ptr;
    using ConstTreePtrType     = typename TreeType::ConstPtr;
    using NonConstTreePtrType  = typename NonConstTreeType::Ptr;
    using GridType             = Grid<TreeType>;
    using NonConstGridType     = Grid<NonConstTreeType>;
    using GridPtrType          = typename GridType::Ptr;
    using NonConstGridPtrType  = typename NonConstGridType::Ptr;
    using ConstGridPtrType     = typename GridType::ConstPtr;
    using ValueType            = typename TreeType::ValueType;
    using AccessorType         = typename tree::ValueAccessor<TreeType>;
    using ConstAccessorType    = typename tree::ValueAccessor<const TreeType>;
    using NonConstAccessorType = typename tree::ValueAccessor<NonConstTreeType>;

    static TreeType& tree(TreeType& t) { return t; }
    static TreeType& tree(GridType& g) { return g.tree(); }
    static TreeType& tree(AccessorType& a) { return a.tree(); }
    static const TreeType& tree(const TreeType& t) { return t; }
    static const TreeType& tree(const GridType& g) { return g.tree(); }
    static const TreeType& tree(const AccessorType& a) { return a.tree(); }
    static const TreeType& constTree(TreeType& t) { return t; }
    static const TreeType& constTree(GridType& g) { return g.constTree(); }
    static const TreeType& constTree(const TreeType& t) { return t; }
    static const TreeType& constTree(const GridType& g) { return g.constTree(); }
};





template<typename LeafNodeType>
struct HasMultiPassIO {
    static const bool value = std::is_base_of<io::MultiPass, LeafNodeType>::value;
};

// Partial specialization for Tree types
template<typename RootNodeType>
struct HasMultiPassIO<tree::Tree<RootNodeType>> {
    // A tree is multi-pass if its (root node's) leaf node type is multi-pass.
    static const bool value = HasMultiPassIO<typename RootNodeType::LeafNodeType>::value;
};

// Partial specialization for Grid types
template<typename TreeType>
struct HasMultiPassIO<Grid<TreeType>> {
    // A grid is multi-pass if its tree's leaf node type is multi-pass.
    static const bool value = HasMultiPassIO<typename TreeType::LeafNodeType>::value;
};




template<typename GridType>
inline typename GridType::Ptr
GridBase::grid(const GridBase::Ptr& grid)
{
    // The string comparison on type names is slower than a dynamic pointer cast, but
    // it is safer when pointers cross DSO boundaries, as they do in many Houdini nodes.
    if (grid && grid->type() == GridType::gridType()) {
        return StaticPtrCast<GridType>(grid);
    }
    return typename GridType::Ptr();
}


template<typename GridType>
inline typename GridType::ConstPtr
GridBase::grid(const GridBase::ConstPtr& grid)
{
    return ConstPtrCast<const GridType>(
        GridBase::grid<GridType>(ConstPtrCast<GridBase>(grid)));
}


template<typename GridType>
inline typename GridType::ConstPtr
GridBase::constGrid(const GridBase::Ptr& grid)
{
    return ConstPtrCast<const GridType>(GridBase::grid<GridType>(grid));
}


template<typename GridType>
inline typename GridType::ConstPtr
GridBase::constGrid(const GridBase::ConstPtr& grid)
{
    return ConstPtrCast<const GridType>(
        GridBase::grid<GridType>(ConstPtrCast<GridBase>(grid)));
}


inline TreeBase::Ptr
GridBase::baseTreePtr()
{
    return ConstPtrCast<TreeBase>(this->constBaseTreePtr());
}


inline void
GridBase::setTransform(math::Transform::Ptr xform)
{
    if (!xform) OPENVDB_THROW(ValueError, "Transform pointer is null");
    mTransform = xform;
}




template<typename TreeT>
inline Grid<TreeT>::Grid(): mTree(new TreeType)
{
}


template<typename TreeT>
inline Grid<TreeT>::Grid(const ValueType &background): mTree(new TreeType(background))
{
}


template<typename TreeT>
inline Grid<TreeT>::Grid(TreePtrType tree): mTree(tree)
{
    if (!tree) OPENVDB_THROW(ValueError, "Tree pointer is null");
}


template<typename TreeT>
inline Grid<TreeT>::Grid(const Grid& other):
    GridBase(other),
    mTree(StaticPtrCast<TreeType>(other.mTree->copy()))
{
}


template<typename TreeT>
template<typename OtherTreeType>
inline Grid<TreeT>::Grid(const Grid<OtherTreeType>& other):
    GridBase(other),
    mTree(new TreeType(other.constTree()))
{
}


#if OPENVDB_ABI_VERSION_NUMBER <= 3
template<typename TreeT>
inline Grid<TreeT>::Grid(const Grid& other, ShallowCopy):
    GridBase(other, ShallowCopy()),
    mTree(other.mTree)
{
}
#else
template<typename TreeT>
inline Grid<TreeT>::Grid(Grid& other, ShallowCopy):
    GridBase(other),
    mTree(other.mTree)
{
}
#endif


template<typename TreeT>
inline Grid<TreeT>::Grid(const GridBase& other):
    GridBase(other),
    mTree(new TreeType)
{
}


//static
template<typename TreeT>
inline typename Grid<TreeT>::Ptr
Grid<TreeT>::create()
{
    return Grid::create(zeroVal<ValueType>());
}


//static
template<typename TreeT>
inline typename Grid<TreeT>::Ptr
Grid<TreeT>::create(const ValueType& background)
{
    return Ptr(new Grid(background));
}


//static
template<typename TreeT>
inline typename Grid<TreeT>::Ptr
Grid<TreeT>::create(TreePtrType tree)
{
    return Ptr(new Grid(tree));
}


//static
template<typename TreeT>
inline typename Grid<TreeT>::Ptr
Grid<TreeT>::create(const GridBase& other)
{
    return Ptr(new Grid(other));
}




#if OPENVDB_ABI_VERSION_NUMBER <= 3

template<typename TreeT>
inline typename Grid<TreeT>::Ptr
Grid<TreeT>::copy(CopyPolicy treePolicy) const
{
    Ptr ret;
    switch (treePolicy) {
        case CP_NEW:
            ret.reset(new Grid(*this, ShallowCopy()));
            ret->newTree();
            break;
        case CP_COPY:
            ret.reset(new Grid(*this));
            break;
        case CP_SHARE:
            ret.reset(new Grid(*this, ShallowCopy()));
            break;
    }
    return ret;
}


template<typename TreeT>
inline GridBase::Ptr
Grid<TreeT>::copyGrid(CopyPolicy treePolicy) const
{
    return this->copy(treePolicy);
}

#else // if OPENVDB_ABI_VERSION_NUMBER > 3

template<typename TreeT>
inline typename Grid<TreeT>::ConstPtr
Grid<TreeT>::copy() const
{
    return ConstPtr{new Grid{*const_cast<Grid*>(this), ShallowCopy{}}};
}

template<typename TreeT>
inline typename Grid<TreeT>::Ptr
Grid<TreeT>::copy()
{
    return Ptr{new Grid{*this, ShallowCopy{}}};
}


template<typename TreeT>
inline typename Grid<TreeT>::Ptr
Grid<TreeT>::copyWithNewTree() const
{
    Ptr result{new Grid{*const_cast<Grid*>(this), ShallowCopy{}}};
    result->newTree();
    return result;
}


template<typename TreeT>
inline GridBase::Ptr
Grid<TreeT>::copyGrid()
{
    return this->copy();
}

template<typename TreeT>
inline GridBase::ConstPtr
Grid<TreeT>::copyGrid() const
{
    return this->copy();
}


template<typename TreeT>
inline GridBase::Ptr
Grid<TreeT>::copyGridWithNewTree() const
{
    return this->copyWithNewTree();
}

#endif




template<typename TreeT>
inline void
Grid<TreeT>::setTree(TreeBase::Ptr tree)
{
    if (!tree) OPENVDB_THROW(ValueError, "Tree pointer is null");
    if (tree->type() != TreeType::treeType()) {
        OPENVDB_THROW(TypeError, "Cannot assign a tree of type "
            + tree->type() + " to a grid of type " + this->type());
    }
    mTree = StaticPtrCast<TreeType>(tree);
}


template<typename TreeT>
inline void
Grid<TreeT>::newTree()
{
    mTree.reset(new TreeType(this->background()));
}




template<typename TreeT>
inline void
Grid<TreeT>::sparseFill(const CoordBBox& bbox, const ValueType& value, bool active)
{
    tree().sparseFill(bbox, value, active);
}


template<typename TreeT>
inline void
Grid<TreeT>::fill(const CoordBBox& bbox, const ValueType& value, bool active)
{
    this->sparseFill(bbox, value, active);
}

template<typename TreeT>
inline void
Grid<TreeT>::denseFill(const CoordBBox& bbox, const ValueType& value, bool active)
{
    tree().denseFill(bbox, value, active);
}

template<typename TreeT>
inline void
Grid<TreeT>::pruneGrid(float tolerance)
{
    OPENVDB_NO_TYPE_CONVERSION_WARNING_BEGIN
    const auto value = zeroVal<ValueType>() + tolerance;
    OPENVDB_NO_TYPE_CONVERSION_WARNING_END
    this->tree().prune(static_cast<ValueType>(value));
}

#if OPENVDB_ABI_VERSION_NUMBER >= 3
template<typename TreeT>
inline void
Grid<TreeT>::clip(const CoordBBox& bbox)
{
    tree().clip(bbox);
}
#endif


template<typename TreeT>
inline void
Grid<TreeT>::merge(Grid& other, MergePolicy policy)
{
    tree().merge(other.tree(), policy);
}


template<typename TreeT>
template<typename OtherTreeType>
inline void
Grid<TreeT>::topologyUnion(const Grid<OtherTreeType>& other)
{
    tree().topologyUnion(other.tree());
}


template<typename TreeT>
template<typename OtherTreeType>
inline void
Grid<TreeT>::topologyIntersection(const Grid<OtherTreeType>& other)
{
    tree().topologyIntersection(other.tree());
}


template<typename TreeT>
template<typename OtherTreeType>
inline void
Grid<TreeT>::topologyDifference(const Grid<OtherTreeType>& other)
{
    tree().topologyDifference(other.tree());
}




template<typename TreeT>
inline void
Grid<TreeT>::evalMinMax(ValueType& minVal, ValueType& maxVal) const
{
    tree().evalMinMax(minVal, maxVal);
}


template<typename TreeT>
inline CoordBBox
Grid<TreeT>::evalActiveVoxelBoundingBox() const
{
    CoordBBox bbox;
    tree().evalActiveVoxelBoundingBox(bbox);
    return bbox;
}


template<typename TreeT>
inline Coord
Grid<TreeT>::evalActiveVoxelDim() const
{
    Coord dim;
    const bool nonempty = tree().evalActiveVoxelDim(dim);
    return (nonempty ? dim : Coord());
}





template<typename TreeT>
inline void
Grid<TreeT>::readTopology(std::istream& is)
{
    tree().readTopology(is, saveFloatAsHalf());
}


template<typename TreeT>
inline void
Grid<TreeT>::writeTopology(std::ostream& os) const
{
    tree().writeTopology(os, saveFloatAsHalf());
}


template<typename TreeT>
inline void
Grid<TreeT>::readBuffers(std::istream& is)
{
    if (!hasMultiPassIO() || (io::getFormatVersion(is) < OPENVDB_FILE_VERSION_MULTIPASS_IO)) {
        tree().readBuffers(is, saveFloatAsHalf());
    } else {
        uint16_t numPasses = 1;
        is.read(reinterpret_cast<char*>(&numPasses), sizeof(uint16_t));
        const io::StreamMetadata::Ptr meta = io::getStreamMetadataPtr(is);
        assert(bool(meta));
        for (uint16_t passIndex = 0; passIndex < numPasses; ++passIndex) {
            uint32_t pass = (uint32_t(numPasses) << 16) | uint32_t(passIndex);
            meta->setPass(pass);
            tree().readBuffers(is, saveFloatAsHalf());
        }
    }
}


#if OPENVDB_ABI_VERSION_NUMBER >= 3

template<typename TreeT>
inline void
Grid<TreeT>::readBuffers(std::istream& is, const CoordBBox& bbox)
{
    if (!hasMultiPassIO() || (io::getFormatVersion(is) < OPENVDB_FILE_VERSION_MULTIPASS_IO)) {
        tree().readBuffers(is, bbox, saveFloatAsHalf());
    } else {
        uint16_t numPasses = 1;
        is.read(reinterpret_cast<char*>(&numPasses), sizeof(uint16_t));
        const io::StreamMetadata::Ptr meta = io::getStreamMetadataPtr(is);
        assert(bool(meta));
        for (uint16_t passIndex = 0; passIndex < numPasses; ++passIndex) {
            uint32_t pass = (uint32_t(numPasses) << 16) | uint32_t(passIndex);
            meta->setPass(pass);
            tree().readBuffers(is, saveFloatAsHalf());
        }
        // Cannot clip inside readBuffers() when using multiple passes,
        // so instead clip afterwards.
        tree().clip(bbox);
    }
}


template<typename TreeT>
inline void
Grid<TreeT>::readNonresidentBuffers() const
{
    tree().readNonresidentBuffers();
}

#endif


template<typename TreeT>
inline void
Grid<TreeT>::writeBuffers(std::ostream& os) const
{
    if (!hasMultiPassIO()) {
        tree().writeBuffers(os, saveFloatAsHalf());
    } else {
        // Determine how many leaf buffer passes are required for this grid
        const io::StreamMetadata::Ptr meta = io::getStreamMetadataPtr(os);
        assert(bool(meta));
        uint16_t numPasses = 1;
        meta->setCountingPasses(true);
        meta->setPass(0);
        tree().writeBuffers(os, saveFloatAsHalf());
        numPasses = static_cast<uint16_t>(meta->pass());
        os.write(reinterpret_cast<const char*>(&numPasses), sizeof(uint16_t));
        meta->setCountingPasses(false);

        // Save out the data blocks of the grid.
        for (uint16_t passIndex = 0; passIndex < numPasses; ++passIndex) {
            uint32_t pass = (uint32_t(numPasses) << 16) | uint32_t(passIndex);
            meta->setPass(pass);
            tree().writeBuffers(os, saveFloatAsHalf());
        }
    }
}


//static
template<typename TreeT>
inline bool
Grid<TreeT>::hasMultiPassIO()
{
    return HasMultiPassIO<Grid>::value;
}


template<typename TreeT>
inline void
Grid<TreeT>::print(std::ostream& os, int verboseLevel) const
{
    tree().print(os, verboseLevel);

    if (metaCount() > 0) {
        os << "Additional metadata:" << std::endl;
        for (ConstMetaIterator it = beginMeta(), end = endMeta(); it != end; ++it) {
            os << "  " << it->first;
            if (it->second) {
                const std::string value = it->second->str();
                if (!value.empty()) os << ": " << value;
            }
            os << "\n";
        }
    }

    os << "Transform:" << std::endl;
    transform().print(os, /*indent=*/"  ");
    os << std::endl;
}




template<typename GridType>
inline typename GridType::Ptr
createGrid(const typename GridType::ValueType& background)
{
    return GridType::create(background);
}


template<typename GridType>
inline typename GridType::Ptr
createGrid()
{
    return GridType::create();
}


template<typename TreePtrType>
inline typename Grid<typename TreePtrType::element_type>::Ptr
createGrid(TreePtrType tree)
{
    using TreeType = typename TreePtrType::element_type;
    return Grid<TreeType>::create(tree);
}


template<typename GridType>
typename GridType::Ptr
createLevelSet(Real voxelSize, Real halfWidth)
{
    using ValueType = typename GridType::ValueType;

    // GridType::ValueType is required to be a floating-point scalar.
    static_assert(std::is_floating_point<ValueType>::value,
        "level-set grids must be floating-point-valued");

    typename GridType::Ptr grid = GridType::create(
        /*background=*/static_cast<ValueType>(voxelSize * halfWidth));
    grid->setTransform(math::Transform::createLinearTransform(voxelSize));
    grid->setGridClass(GRID_LEVEL_SET);
    return grid;
}




namespace internal {

template<typename OpT, typename GridBaseT, typename T, typename ...Ts>
struct GridApplyImpl { static bool apply(GridBaseT&, OpT&) { return false; } };

// Partial specialization for (nonempty) TypeLists
template<typename OpT, typename GridBaseT, typename GridT, typename ...GridTs>
struct GridApplyImpl<OpT, GridBaseT, TypeList<GridT, GridTs...>>
{
    static bool apply(GridBaseT& grid, OpT& op)
    {
        if (grid.template isType<GridT>()) {
            op(static_cast<typename CopyConstness<GridBaseT, GridT>::Type&>(grid));
            return true;
        }
        return GridApplyImpl<OpT, GridBaseT, TypeList<GridTs...>>::apply(grid, op);
    }
};

} // namespace internal


template<typename GridTypeListT, typename OpT>
inline bool
GridBase::apply(OpT& op) const
{
    return internal::GridApplyImpl<OpT, const GridBase, GridTypeListT>::apply(*this, op);
}

template<typename GridTypeListT, typename OpT>
inline bool
GridBase::apply(OpT& op)
{
    return internal::GridApplyImpl<OpT, GridBase, GridTypeListT>::apply(*this, op);
}

template<typename GridTypeListT, typename OpT>
inline bool
GridBase::apply(const OpT& op) const
{
    return internal::GridApplyImpl<const OpT, const GridBase, GridTypeListT>::apply(*this, op);
}

template<typename GridTypeListT, typename OpT>
inline bool
GridBase::apply(const OpT& op)
{
    return internal::GridApplyImpl<const OpT, GridBase, GridTypeListT>::apply(*this, op);
}

} // namespace OPENVDB_VERSION_NAME
} // namespace openvdb

#endif // OPENVDB_GRID_HAS_BEEN_INCLUDED

// Copyright (c) DreamWorks Animation LLC
// All rights reserved. This software is distributed under the
// Mozilla Public License 2.0 ( http://www.mozilla.org/MPL/2.0/ )