Resource.hpp

//
// SFML - Simple and Fast Multimedia Library
// Copyright (C) 2007 Laurent Gomila (laurent.gom@gmail.com)
//
// This software is provided 'as-is', without any express or implied warranty.
// In no event will the authors be held liable for any damages arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it freely,
// subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented;
//    you must not claim that you wrote the original software.
//    If you use this software in a product, an acknowledgment
//    in the product documentation would be appreciated but is not required.
//
// 2. Altered source versions must be plainly marked as such,
//    and must not be misrepresented as being the original software.
//
// 3. This notice may not be removed or altered from any source distribution.
//
 
#ifndef SFML_RESOURCE_HPP
#define SFML_RESOURCE_HPP

// Headers
#include <set>
#include <cstddef>
 
namespace sf
{
// These two classes are defined in the same header because
// they depend on each other. And as they're template classes,
// they must be entirely defined in header files, which
// prevents from proper separate compiling
////////////////////////////////////////////////////////////
 
template <typename> class ResourcePtr;


template <typename T>
class Resource
{
protected :

    ////////////////////////////////////////////////////////////
    /// Default constructor
    ///
    ////////////////////////////////////////////////////////////
    Resource();

    ////////////////////////////////////////////////////////////
    Resource(const Resource<T>& Copy);


    ~Resource();

    /// \param Other : Resource to copy
    ///
    /// \return Reference to this
    ///
    ////////////////////////////////////////////////////////////
    Resource<T>& operator =(const Resource<T>& Other);
 
private :
 
    friend class ResourcePtr<T>;

    void Connect(ResourcePtr<T>& Observer) const;

    void Disconnect(ResourcePtr<T>& Observer) const;

    // Member data
    mutable std::set<ResourcePtr<T>*> myObservers;
};
 

template <typename T>
class ResourcePtr
{
public :


    ResourcePtr();

    ////////////////////////////////////////////////////////////
    /// Construct from a raw resource
    ///
    /// \param Resource : Internal resource
    ///
    ////////////////////////////////////////////////////////////
    ResourcePtr(const T* Resource);

    ///
    /// \param Copy : Instance to copy
    ///
    ////////////////////////////////////////////////////////////
    ResourcePtr(const ResourcePtr<T>& Copy);

    ~ResourcePtr();


    ResourcePtr<T>& operator =(const ResourcePtr<T>& Other);

    ResourcePtr<T>& operator =(const T* Resource);

    operator const T*() const;

    const T& operator *() const;

    const T* operator ->() const;

    void OnResourceDestroyed();
 
private :

    // Member data
    const T* myResource; 
};
 
#include <SFML/System/Resource.inl>
#include <SFML/System/ResourcePtr.inl>
 
} // namespace sf
 
 
#endif // SFML_RESOURCE_HPP