#ifndef adskDataIndexType_h #define adskDataIndexType_h #include #include // For IndexCount #include // For base class #include // For CRTP methods // Forward declaration of member data namespace adsk { namespace Data { // **************************************************************************** /*! \class adsk::Data::IndexType \brief Complex index type for referencing metadata. adsk::Data::Stream objects contain a list of data elements. Each element has to be accessed by Index. This is the base class for the complex index types. */ class METADATA_EXPORT IndexType : public RefCounted // Since this class is virtual there is no // need to use an extern template to prevent // multiple instantiations since it cannot // be instantiated by itself at all. // Derived classes still need it though. { protected: friend class Index; virtual ~IndexType (); IndexType (); public: //---------------------------------------------------------------------- // Constructors and assignment operator. Base class provides as little // implementation as possible. The derived classes do the heavy lifting. IndexType ( const IndexType& rhs ); /*! \fn IndexType* clone() const \brief Create a duplicate of this object. This is virtual so that derived types create the correct type of object. \return Pointer to copy of this object */ virtual IndexType* clone () const = 0; /*! \fn std::string asString() const \brief Get this index type value as a string \return The index type value in string form (as expected by the string constructor) */ virtual std::string asString () const = 0; /*! \fn bool supportsDenseMode() const \brief Check if this object type supports dense packing indexing \return true if the index type supports dense packing */ virtual bool supportsDenseMode () const = 0; /*! \fn IndexCount denseSpaceBetween(const IndexType& rhs) const \brief Calculate the number of elements to be packed between this one and the rhs \param[in] rhs Object from which the packing size is calculated \return Number of index values between this one and the rhs */ virtual IndexCount denseSpaceBetween ( const IndexType& rhs ) const = 0; //---------------------------------------------------------------------- // Comparison operators for easy sorting // /*! \fn bool operator==( const IndexType& rhs ) const \brief Equality comparison of this object and the rhs \param[in] rhs Object being compared against \return true if the two objects are equal */ virtual bool operator== (const IndexType& rhs) const = 0; /*! \fn bool operator!=( const IndexType& rhs ) const \brief Unequality comparison of this object and the rhs \param[in] rhs Object being compared against \return true if the two objects are not equal */ virtual bool operator!= (const IndexType& rhs) const = 0; /*! \fn bool operator==( const IndexType& rhs ) const \brief GE-inequality comparison of this object and the rhs \param[in] rhs Object being compared against \return true if this object is less than the rhs */ virtual bool operator< (const IndexType& rhs) const = 0; /*! \fn bool operator<( const IndexType& rhs ) const \brief LT-inequality comparison of this object and the rhs \param[in] rhs Object being compared against \return true if this object is less than or equal to the rhs */ virtual bool operator<= (const IndexType& rhs) const = 0; /*! \fn bool operator<=( const IndexType& rhs ) const \brief LE-inequality comparison of this object and the rhs \param[in] rhs Object being compared against \return true if this object is greater than the rhs */ virtual bool operator> (const IndexType& rhs) const = 0; /*! \fn bool operator==( const IndexType& rhs ) const \brief GT-inequality comparison of this object and the rhs \param[in] rhs Object being compared against \return true if this object is greater than or equal to the rhs */ virtual bool operator>= (const IndexType& rhs) const = 0; /*! \fn std::string typeName() const \brief Get the unique name of this index type \return String containing the index type name */ virtual std::string typeName () const = 0; protected: //! \class adsk::Data::IndexType::IndexRegistration //! \brief Helper class to automatically register new index types. //! Construction of an object of this class will register a //! new index type with the global registry. class IndexRegistration { public: IndexRegistration( const std::string& typeName, Index::IndexCreator creator ) { (void) Index::registerType(typeName, creator); } }; }; //---------------------------------------------------------------------- /*! This CRTP (Curiously Recurring Template Pattern) class implements some shared methods which all derived classes can use, and for whom the implementations use the same pattern. For all derived index types use this declaration for the class: class METADATA_EXPORT MyIndex : public CRTP_IndexType { ... } This will automatically instantiate a common clone() method as well as establishing the abstract interface each index type needs to implement. */ template class CRTP_IndexType : public IndexType { public: //---------------------------------------------------------------------- // clone() virtual method creates an object of the derived type virtual IndexType* clone () const { return new Derived(static_cast(*this)); } // Static creation method used to define a new Index from a description. // Class must provide a constructor from a string. static Index doCreate( const std::string& value ) { return Index( Derived( value ) ); } // Virtual and static methods to get the name of the index type virtual std::string typeName() const { return Derived::myTypeName; } static std::string theTypeName() { return Derived::myTypeName; } }; } // namespace Data } // namespace adsk //========================================================= //- // Copyright 2015 Autodesk, Inc. All rights reserved. // Use of this software is subject to the terms of the // Autodesk license agreement provided at the time of // installation or download, or which otherwise accompanies // this software in either electronic or hard copy form. //+ //========================================================= #endif // adskDataIndexType_h