source: GTP/trunk/App/Demos/Geom/OgreStuff/include/OgreSceneManagerEnumerator.h @ 1812

/*
-----------------------------------------------------------------------------
This source file is part of OGRE
    (Object-oriented Graphics Rendering Engine)
For the latest info, see http://www.ogre3d.org/

Copyright (c) 2000-2005 The OGRE Team
Also see acknowledgements in Readme.html

This program is free software; you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License as published by the Free Software
Foundation; either version 2 of the License, or (at your option) any later
version.

This program 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 Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with
this program; if not, write to the Free Software Foundation, Inc., 59 Temple
Place - Suite 330, Boston, MA 02111-1307, USA, or go to
http://www.gnu.org/copyleft/lesser.txt.
-----------------------------------------------------------------------------
*/
#ifndef __SceneManagerEnumerator_H__
#define __SceneManagerEnumerator_H__

#include "OgrePrerequisites.h"

#include "OgreSceneManager.h"
#include "OgreSingleton.h"
#include "OgreIteratorWrappers.h"

namespace Ogre {
    
        /// Factory for default scene manager
        class _OgreExport DefaultSceneManagerFactory : public SceneManagerFactory
        {
        protected:
                void initMetaData(void) const;
        public:
                DefaultSceneManagerFactory() {}
                ~DefaultSceneManagerFactory() {}
                /// Factory type name
                static const String FACTORY_TYPE_NAME;
                SceneManager* createInstance(const String& instanceName);
                void destroyInstance(SceneManager* instance);
        };
        /// Default scene manager
        class _OgreExport DefaultSceneManager : public SceneManager
        {
        public:
                DefaultSceneManager(const String& name);
                ~DefaultSceneManager();
                const String& getTypeName(void) const;
        };

    /** Enumerates the SceneManager classes available to applications.
        @remarks
            As described in the SceneManager class, SceneManagers are responsible
            for organising the scene and issuing rendering commands to the
            RenderSystem. Certain scene types can benefit from different
            rendering approaches, and it is intended that subclasses will
            be created to special case this.
        @par
            In order to give applications easy access to these implementations,
            this class has a number of methods to create or retrieve a SceneManager
            which is appropriate to the scene type. 
                @par
                        SceneManagers are created by SceneManagerFactory instances. New factories
                        for new types of SceneManager can be registered with this class to make
                        them available to clients.
                @par
                        Note that you can still plug in your own custom SceneManager without
                        using a factory, should you choose, it's just not as flexible that way.
                        Just instantiate your own SceneManager manually and use it directly.
    */
    class _OgreExport SceneManagerEnumerator : public Singleton<SceneManagerEnumerator>
    {
        public:
                /// Scene manager instances, indexed by instance name
                typedef std::map<String, SceneManager*> Instances;
                /// List of available scene manager types as meta data
                typedef std::vector<const SceneManagerMetaData*> MetaDataList;
    private:
                /// Scene manager factories
                typedef std::list<SceneManagerFactory*> Factories;
                Factories mFactories;
                Instances mInstances;
                /// Stored separately to allow iteration
                MetaDataList mMetaDataList;
                /// Factory for default scene manager
                DefaultSceneManagerFactory mDefaultFactory;
                /// Count of creations for auto-naming
                unsigned long mInstanceCreateCount;
                /// Currently assigned render system
                RenderSystem* mCurrentRenderSystem;


    public:
        SceneManagerEnumerator();
        ~SceneManagerEnumerator();

                /** Register a new SceneManagerFactory. 
                @remarks
                        Plugins should call this to register as new SceneManager providers.
                */
                void addFactory(SceneManagerFactory* fact);

                /** Remove a SceneManagerFactory. 
                */
                void removeFactory(SceneManagerFactory* fact);

                /** Get more information about a given type of SceneManager.
                @remarks
                        The metadata returned tells you a few things about a given type 
                        of SceneManager, which can be created using a factory that has been
                        registered already. 
                @param typeName The type name of the SceneManager you want to enquire on.
                        If you don't know the typeName already, you can iterate over the 
                        metadata for all types using getMetaDataIterator.
                */
                const SceneManagerMetaData* getMetaData(const String& typeName) const;

                typedef ConstVectorIterator<MetaDataList> MetaDataIterator;
                /** Iterate over all types of SceneManager available for construction, 
                        providing some information about each one.
                */
                MetaDataIterator getMetaDataIterator(void) const;

                /** Create a SceneManager instance of a given type.
                @remarks
                        You can use this method to create a SceneManager instance of a 
                        given specific type. You may know this type already, or you may
                        have discovered it by looking at the results from getMetaDataIterator.
                @note
                        This method throws an exception if the named type is not found.
                @param typeName String identifying a unique SceneManager type
                @param instanceName Optional name to given the new instance that is
                        created. If you leave this blank, an auto name will be assigned.
                */
                SceneManager* createSceneManager(const String& typeName, 
                        const String& instanceName = StringUtil::BLANK);

                /** Create a SceneManager instance based on scene type support.
                @remarks
                        Creates an instance of a SceneManager which supports the scene types
                        identified in the parameter. If more than one type of SceneManager 
                        has been registered as handling that combination of scene types, 
                        in instance of the last one registered is returned.
                @note This method always succeeds, if a specific scene manager is not
                        found, the default implementation is always returned.
                @param typeMask A mask containing one or more SceneType flags
                @param instanceName Optional name to given the new instance that is
                        created. If you leave this blank, an auto name will be assigned.
                */
                SceneManager* createSceneManager(SceneTypeMask typeMask, 
                        const String& instanceName = StringUtil::BLANK);

                /** Destroy an instance of a SceneManager. */
                void destroySceneManager(SceneManager* sm);

                /** Get an existing SceneManager instance that has already been created,
                        identified by the instance name.
                @param instanceName The name of the instance to retrieve.
                */
                SceneManager* getSceneManager(const String& instanceName) const;

                typedef MapIterator<Instances> SceneManagerIterator;
                /** Get an iterator over all the existing SceneManager instances. */
                SceneManagerIterator getSceneManagerIterator(void);

        /** Notifies all SceneManagers of the destination rendering system.
        */
        void setRenderSystem(RenderSystem* rs);

        /// Utility method to control shutdown of the managers
        void shutdownAll(void);
        /** Override standard Singleton retrieval.
        @remarks
        Why do we do this? Well, it's because the Singleton
        implementation is in a .h file, which means it gets compiled
        into anybody who includes it. This is needed for the
        Singleton template to work, but we actually only want it
        compiled into the implementation of the class based on the
        Singleton, not all of them. If we don't change this, we get
        link errors when trying to use the Singleton-based class from
        an outside dll.
        @par
        This method just delegates to the template version anyway,
        but the implementation stays in this single compilation unit,
        preventing link errors.
        */
        static SceneManagerEnumerator& getSingleton(void);
        /** Override standard Singleton retrieval.
        @remarks
        Why do we do this? Well, it's because the Singleton
        implementation is in a .h file, which means it gets compiled
        into anybody who includes it. This is needed for the
        Singleton template to work, but we actually only want it
        compiled into the implementation of the class based on the
        Singleton, not all of them. If we don't change this, we get
        link errors when trying to use the Singleton-based class from
        an outside dll.
        @par
        This method just delegates to the template version anyway,
        but the implementation stays in this single compilation unit,
        preventing link errors.
        */
        static SceneManagerEnumerator* getSingletonPtr(void);

    };


}

#endif