/* ----------------------------------------------------------------------------- This source file is part of OGRE (Object-oriented Graphics Rendering Engine) For the latest info, see http://www.ogre3d.org/ Copyright (c) 2000-2006 Torus Knot Software Ltd 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. You may alternatively use this source under the terms of a specific version of the OGRE Unrestricted License provided you have obtained such a license from Torus Knot Software Ltd. ----------------------------------------------------------------------------- */ #ifndef _ResourceManager_H__ #define _ResourceManager_H__ #include "OgrePrerequisites.h" #include "OgreResource.h" #include "OgreResourceGroupManager.h" #include "OgreIteratorWrappers.h" #include "OgreCommon.h" #include "OgreDataStream.h" #include "OgreStringVector.h" #include "OgreScriptLoader.h" namespace Ogre { /** Defines a generic resource handler. @remarks A resource manager is responsible for managing a pool of resources of a particular type. It must index them, look them up, load and destroy them. It may also need to stay within a defined memory budget, and temporaily unload some resources if it needs to to stay within this budget. @par Resource managers use a priority system to determine what can be unloaded, and a Least Recently Used (LRU) policy within resources of the same priority. @par Resources can be loaded using the generalised load interface, and they can be unloaded and removed. In addition, each subclass of ResourceManager will likely define custom 'load' methods which take explicit parameters depending on the kind of resource being created. @note Resources can be loaded and unloaded through the Resource class, but they can only be removed (and thus eventually destroyed) using their parent ResourceManager. @note If OGRE_THREAD_SUPPORT is 1, this class is thread-safe. */ class _OgreExport ResourceManager : public ScriptLoader { public: OGRE_AUTO_MUTEX // public to allow external locking ResourceManager(); virtual ~ResourceManager(); /** Creates a new blank resource, but does not immediately load it. @remarks Resource managers handle disparate types of resources, so if you want to get at the detailed interface of this resource, you'll have to cast the result to the subclass you know you're creating. @param name The unique name of the resource @param group The name of the resource group to attach this new resource to @param isManual Is this resource manually loaded? If so, you should really populate the loader parameter in order that the load process can call the loader back when loading is required. @param loader Pointer to a ManualLoader implementation which will be called when the Resource wishes to load (should be supplied if you set isManual to true). You can in fact leave this parameter null if you wish, but the Resource will never be able to reload if anything ever causes it to unload. Therefore provision of a proper ManualLoader instance is strongly recommended. @param createParams If any parameters are required to create an instance, they should be supplied here as name / value pairs */ virtual ResourcePtr create(const String& name, const String& group, bool isManual = false, ManualResourceLoader* loader = 0, const NameValuePairList* createParams = 0); typedef std::pair ResourceCreateOrRetrieveResult; /** Create a new resource, or retrieve an existing one with the same name if it already exists. @remarks This method performs the same task as calling getByName() followed by create() if that returns null. The advantage is that it does it in one call so there are no race conditions if using multiple threads that could cause getByName() to return null, but create() to fail because another thread created a resource in between. @see ResourceManager::create @see ResourceManager::getByName @returns A pair, the first element being the pointer, and the second being an indicator specifying whether the resource was newly created. */ virtual ResourceCreateOrRetrieveResult createOrRetrieve(const String& name, const String& group, bool isManual = false, ManualResourceLoader* loader = 0, const NameValuePairList* createParams = 0); /** Set a limit on the amount of memory this resource handler may use. @remarks If, when asked to load a new resource, the manager believes it will exceed this memory budget, it will temporarily unload a resource to make room for the new one. This unloading is not permanent and the Resource is not destroyed; it simply needs to be reloaded when next used. */ virtual void setMemoryBudget( size_t bytes); /** Get the limit on the amount of memory this resource handler may use. */ virtual size_t getMemoryBudget(void) const; /** Gets the current memory usage, in bytes. */ virtual size_t getMemoryUsage(void) const { return mMemoryUsage; } /** Unloads a single resource by name. @remarks Unloaded resources are not removed, they simply free up their memory as much as they can and wait to be reloaded. @see ResourceGroupManager for unloading of resource groups. */ virtual void unload(const String& name); /** Unloads a single resource by handle. @remarks Unloaded resources are not removed, they simply free up their memory as much as they can and wait to be reloaded. @see ResourceGroupManager for unloading of resource groups. */ virtual void unload(ResourceHandle handle); /** Unloads all resources. @remarks Unloaded resources are not removed, they simply free up their memory as much as they can and wait to be reloaded. @see ResourceGroupManager for unloading of resource groups. @param reloadableOnly If true (the default), only unload the resource that is reloadable. Because some resources isn't reloadable, they will be unloaded but can't load them later. Thus, you might not want to them unloaded. Or, you might unload all of them, and then populate them manually later. @see Resource::isReloadable for resource is reloadable. */ virtual void unloadAll(bool reloadableOnly = true); /** Caused all currently loaded resources to be reloaded. @remarks All resources currently being held in this manager which are also marked as currently loaded will be unloaded, then loaded again. @param reloadableOnly If true (the default), only reload the resource that is reloadable. Because some resources isn't reloadable, they will be unloaded but can't loaded again. Thus, you might not want to them unloaded. Or, you might unload all of them, and then populate them manually later. @see Resource::isReloadable for resource is reloadable. */ virtual void reloadAll(bool reloadableOnly = true); /** Unload all resources which are not referenced by any other object. @remarks This method behaves like unloadAll, except that it only unloads resources which are not in use, ie not referenced by other objects. This allows you to free up some memory selectively whilst still keeping the group around (and the resources present, just not using much memory). @par Some referenced resource may exists 'weak' pointer to their sub-components (e.g. Entity held pointer to SubMesh), in this case, unload or reload that resource will cause dangerous pointer access. Use this function instead of unloadAll allows you avoid fail in those situations. @param reloadableOnly If true (the default), only unloads resources which can be subsequently automatically reloaded. */ virtual void unloadUnreferencedResources(bool reloadableOnly = true); /** Caused all currently loaded but not referenced by any other object resources to be reloaded. @remarks This method behaves like reloadAll, except that it only reloads resources which are not in use, ie not referenced by other objects. @par Some referenced resource may exists 'weak' pointer to their sub-components (e.g. Entity held pointer to SubMesh), in this case, unload or reload that resource will cause dangerous pointer access. Use this function instead of reloadAll allows you avoid fail in those situations. @param reloadableOnly If true (the default), only reloads resources which can be subsequently automatically reloaded. */ virtual void reloadUnreferencedResources(bool reloadableOnly = true); /** Remove a single resource. @remarks Removes a single resource, meaning it will be removed from the list of valid resources in this manager, also causing it to be unloaded. @note The word 'Destroy' is not used here, since if any other pointers are referring to this resource, it will persist until they have finished with it; however to all intents and purposes it no longer exists and will likely get destroyed imminently. @note If you do have shared pointers to resources hanging around after the ResourceManager is destroyed, you may get problems on destruction of these resources if they were relying on the manager (especially if it is a plugin). If you find you get problems on shutdown in the destruction of resources, try making sure you release all your shared pointers before you shutdown OGRE. */ virtual void remove(ResourcePtr& r); /** Remove a single resource by name. @remarks Removes a single resource, meaning it will be removed from the list of valid resources in this manager, also causing it to be unloaded. @note The word 'Destroy' is not used here, since if any other pointers are referring to this resource, it will persist until they have finished with it; however to all intents and purposes it no longer exists and will likely get destroyed imminently. @note If you do have shared pointers to resources hanging around after the ResourceManager is destroyed, you may get problems on destruction of these resources if they were relying on the manager (especially if it is a plugin). If you find you get problems on shutdown in the destruction of resources, try making sure you release all your shared pointers before you shutdown OGRE. */ virtual void remove(const String& name); /** Remove a single resource by handle. @remarks Removes a single resource, meaning it will be removed from the list of valid resources in this manager, also causing it to be unloaded. @note The word 'Destroy' is not used here, since if any other pointers are referring to this resource, it will persist until they have finished with it; however to all intents and purposes it no longer exists and will likely get destroyed imminently. @note If you do have shared pointers to resources hanging around after the ResourceManager is destroyed, you may get problems on destruction of these resources if they were relying on the manager (especially if it is a plugin). If you find you get problems on shutdown in the destruction of resources, try making sure you release all your shared pointers before you shutdown OGRE. */ virtual void remove(ResourceHandle handle); /** Removes all resources. @note The word 'Destroy' is not used here, since if any other pointers are referring to these resources, they will persist until they have been finished with; however to all intents and purposes the resources no longer exist and will get destroyed imminently. @note If you do have shared pointers to resources hanging around after the ResourceManager is destroyed, you may get problems on destruction of these resources if they were relying on the manager (especially if it is a plugin). If you find you get problems on shutdown in the destruction of resources, try making sure you release all your shared pointers before you shutdown OGRE. */ virtual void removeAll(void); /** Retrieves a pointer to a resource by name, or null if the resource does not exist. */ virtual ResourcePtr getByName(const String& name); /** Retrieves a pointer to a resource by handle, or null if the resource does not exist. */ virtual ResourcePtr getByHandle(ResourceHandle handle); /// Returns whether the named resource exists in this manager virtual bool resourceExists(const String& name) { return !getByName(name).isNull(); } /// Returns whether a resource with the given handle exists in this manager virtual bool resourceExists(ResourceHandle handle) { return !getByHandle(handle).isNull(); } /** Notify this manager that a resource which it manages has been 'touched', ie used. */ virtual void _notifyResourceTouched(Resource* res); /** Notify this manager that a resource which it manages has been loaded. */ virtual void _notifyResourceLoaded(Resource* res); /** Notify this manager that a resource which it manages has been unloaded. */ virtual void _notifyResourceUnloaded(Resource* res); /** Generic load method, used to create a Resource specific to this ResourceManager without using one of the specialised 'load' methods (containing per-Resource-type parameters). @param name The name of the Resource @param group The resource group to which this resource will belong @param isManual Is the resource to be manually loaded? If so, you should provide a value for the loader parameter @param loader The manual loader which is to perform the required actions when this resource is loaded; only applicable when you specify true for the previous parameter @param loadParams Optional pointer to a list of name/value pairs containing loading parameters for this type of resource. */ virtual ResourcePtr load(const String& name, const String& group, bool isManual = false, ManualResourceLoader* loader = 0, const NameValuePairList* loadParams = 0); /** Gets the file patterns which should be used to find scripts for this ResourceManager. @remarks Some resource managers can read script files in order to define resources ahead of time. These resources are added to the available list inside the manager, but none are loaded initially. This allows you to load the items that are used on demand, or to load them all as a group if you wish (through ResourceGroupManager). @par This method lets you determine the file pattern which will be used to identify scripts intended for this manager. @returns A list of file patterns, in the order they should be searched in. @see isScriptingSupported, parseScript */ virtual const StringVector& getScriptPatterns(void) const { return mScriptPatterns; } /** Parse the definition of a set of resources from a script file. @remarks Some resource managers can read script files in order to define resources ahead of time. These resources are added to the available list inside the manager, but none are loaded initially. This allows you to load the items that are used on demand, or to load them all as a group if you wish (through ResourceGroupManager). @param stream Weak reference to a data stream which is the source of the script @param groupName The name of the resource group that resources which are parsed are to become a member of. If this group is loaded or unloaded, then the resources discovered in this script will be loaded / unloaded with it. */ virtual void parseScript(DataStreamPtr& stream, const String& groupName) {} /** Gets the relative loading order of resources of this type. @remarks There are dependencies between some kinds of resource in terms of loading order, and this value enumerates that. Higher values load later during bulk loading tasks. */ virtual Real getLoadingOrder(void) const { return mLoadOrder; } /** Gets a string identifying the type of resource this manager handles. */ const String& getResourceType(void) const { return mResourceType; } protected: /** Allocates the next handle. */ ResourceHandle getNextHandle(void); /** Create a new resource instance compatible with this manager (no custom parameters are populated at this point). @remarks Subclasses must override this method and create a subclass of Resource. @param name The unique name of the resource @param group The name of the resource group to attach this new resource to @param isManual Is this resource manually loaded? If so, you should really populate the loader parameter in order that the load process can call the loader back when loading is required. @param loader Pointer to a ManualLoader implementation which will be called when the Resource wishes to load (should be supplied if you set isManual to true). You can in fact leave this parameter null if you wish, but the Resource will never be able to reload if anything ever causes it to unload. Therefore provision of a proper ManualLoader instance is strongly recommended. @param createParams If any parameters are required to create an instance, they should be supplied here as name / value pairs. These do not need to be set on the instance (handled elsewhere), just used if required to differentiate which concrete class is created. */ virtual Resource* createImpl(const String& name, ResourceHandle handle, const String& group, bool isManual, ManualResourceLoader* loader, const NameValuePairList* createParams) = 0; /** Add a newly created resource to the manager (note weak reference) */ virtual void addImpl( ResourcePtr& res ); /** Remove a resource from this manager; remove it from the lists. */ virtual void removeImpl( ResourcePtr& res ); /** Checks memory usage and pages out if required. */ virtual void checkUsage(void); public: typedef HashMap< String, ResourcePtr > ResourceMap; typedef std::map ResourceHandleMap; protected: ResourceHandleMap mResourcesByHandle; ResourceMap mResources; ResourceHandle mNextHandle; size_t mMemoryBudget; // In bytes size_t mMemoryUsage; // In bytes // IMPORTANT - all subclasses must populate the fields below /// Patterns to use to look for scripts if supported (e.g. *.overlay) StringVector mScriptPatterns; /// Loading order relative to other managers, higher is later Real mLoadOrder; /// String identifying the resource type this manager handles String mResourceType; public: typedef MapIterator ResourceMapIterator; /** Returns an iterator over all resources in this manager. @note Use of this iterator is NOT thread safe! */ ResourceMapIterator getResourceIterator(void) { return ResourceMapIterator(mResourcesByHandle.begin(), mResourcesByHandle.end()); } }; } #endif