OpenSceneGraph/include/osgDB/DotOsgWrapper

/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2006 Robert Osfield 
 *
 * This library is open source and may be redistributed and/or modified under  
 * the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or 
 * (at your option) any later version.  The full license is in LICENSE file
 * included with this distribution, and on the openscenegraph.org website.
 * 
 * This library 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 
 * OpenSceneGraph Public License for more details.
*/

#ifndef OSGDB_DOTOSGWRAPPER
#define OSGDB_DOTOSGWRAPPER 1

#include <osg/ref_ptr>
#include <osg/Object>

#include <osgDB/Input>
#include <osgDB/Output>

#include <string>
#include <vector>

namespace osgDB {


/** Wrapper class for specifying read and write functions for extending
  * the .osg file format. */ 
class OSGDB_EXPORT DotOsgWrapper : public osg::Referenced
{
    public:

        typedef std::vector<std::string> Associates;
        typedef bool (*ReadFunc)(osg::Object&,osgDB::Input&);
        typedef bool (*WriteFunc)(const osg::Object&,osgDB::Output&);
        
        enum ReadWriteMode
        {
            READ_AND_WRITE,
            READ_ONLY
        };

        DotOsgWrapper(osg::Object* proto,
                      const std::string& name,
                      const std::string& associates,
                      ReadFunc readFunc,
                      WriteFunc writeFunc,
                      ReadWriteMode readWriteMode=READ_AND_WRITE);
                      

        inline const osg::Object* getPrototype() const { return _prototype.get(); }
        inline const std::string& getName() const      { return _name; }
        inline const Associates& getAssociates() const { return _associates; }
        inline ReadFunc getReadFunc() const            { return _readFunc; }
        inline WriteFunc getWriteFunc() const          { return _writeFunc; }
        inline ReadWriteMode getReadWriteMode() const  { return _readWriteMode; }

    protected:

        /// protected to prevent inappropriate creation of wrappers.
        DotOsgWrapper() {}

        /// protected to prevent inappropriate creation of wrappers.
        DotOsgWrapper(DotOsgWrapper&):osg::Referenced() {}

        /// protected to prevent wrapper being created on stack.
        virtual ~DotOsgWrapper() {}

        osg::ref_ptr<osg::Object>   _prototype;
        
        std::string                 _name;
        Associates                  _associates;
        
        ReadFunc                    _readFunc;
        WriteFunc                   _writeFunc;

        ReadWriteMode               _readWriteMode;
};

/**  Proxy class for automatic registration of DotOsgWrappers with the Registry.*/
class OSGDB_EXPORT RegisterDotOsgWrapperProxy
{
    public:

        RegisterDotOsgWrapperProxy(osg::Object* proto,
                                   const std::string& name,
                                   const std::string& associates,
                                   DotOsgWrapper::ReadFunc readFunc,
                                   DotOsgWrapper::WriteFunc writeFunc,
                                   DotOsgWrapper::ReadWriteMode readWriteMode=DotOsgWrapper::READ_AND_WRITE);

        ~RegisterDotOsgWrapperProxy();

    protected:
        osg::ref_ptr<DotOsgWrapper> _wrapper;
};

template<class T>
class OSGDB_EXPORT TemplateRegisterDotOsgWrapperProxy : public RegisterDotOsgWrapperProxy, public T
{
    public:

        TemplateRegisterDotOsgWrapperProxy(osg::Object* proto,
                                   const std::string& name,
                                   const std::string& associates,
                                   DotOsgWrapper::ReadFunc readFunc,
                                   DotOsgWrapper::WriteFunc writeFunc,
                                   DotOsgWrapper::ReadWriteMode readWriteMode=DotOsgWrapper::READ_AND_WRITE):
            RegisterDotOsgWrapperProxy(proto, name, associates, readFunc, writeFunc, readWriteMode) {}

};


#define REGISTER_DOTOSGWRAPPER(classname) \
    extern "C" void dotosgwrapper_##classname(void) {} \
    static osgDB::RegisterDotOsgWrapperProxy dotosgwrapper_proxy_##classname

}

#endif