OpenSceneGraph/include/osgDB/ReaderWriter
Robert Osfield 7b003b24ea Refactored DatabasePager and related classes to introduce support for
multi-threaded paging, where the Pager manages threads of reading local
and http files via seperate threads.  This makes it possible to smoothly
browse large databases where parts of the data are locally cached while
others are on a remote server.  Previously with this type of dataset 
the pager would stall all paging while http requests were being served,
even when parts of the models are still loadable virtue of being in the 
local cache.

Also as part of the refactoring the DatabaseRequest are now stored in the
ProxyNode/PagedLOD nodes to facilitate quite updating in the cull traversal,
with the new code avoiding mutex locks and searches.  Previous on big 
databases the overhead involved in make database requests could accumulate
to a point where it'd cause the cull traversal to break frame.  The overhead
now is negligable.

Finally OSG_FILE_CACHE support has been moved from the curl plugin into
the DatabasePager.  Eventually this functionality will be moved out into
osgDB for more general usage.
2008-05-21 21:09:45 +00:00

292 lines
14 KiB
C++

/* -*-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_READERWRITER
#define OSGDB_READERWRITER 1
#include <osg/Referenced>
#include <osg/Image>
#include <osg/Shape>
#include <osg/Node>
#include <osgDB/Export>
#include <deque>
#include <iosfwd>
namespace osgDB {
class Archive;
/** list of directories to search through which searching for files. */
typedef std::deque<std::string> FilePathList;
/** pure virtual base class for reading and writing of non native formats. */
class OSGDB_EXPORT ReaderWriter : public osg::Object
{
public:
ReaderWriter():
osg::Object(true) {}
ReaderWriter(const ReaderWriter& rw,const osg::CopyOp& copyop=osg::CopyOp::SHALLOW_COPY):
osg::Object(rw,copyop) {}
virtual ~ReaderWriter();
META_Object(osgDB,ReaderWriter);
virtual bool acceptsExtension(const std::string& /*extension*/) const { return false; }
/** Options base class used for passing options into plugins to control their operation.*/
class Options : public osg::Object
{
public:
/// bit mask for setting up which object types get cached by readObject/Image/HeightField/Node(filename) calls
enum CacheHintOptions
{ /// do not cache objects of any type
CACHE_NONE = 0,
/// cache nodes loaded via readNode(filename)
CACHE_NODES = 1<<0,
/// cache images loaded via readImage(filename)
CACHE_IMAGES = 1<<1,
/// cache heightfield loaded via readHeightField(filename)
CACHE_HEIGHTFIELDS = 1<<2,
/// cache heightfield loaded via readHeightField(filename)
CACHE_ARCHIVES = 1<<3,
/// cache objects loaded via readObject(filename)
CACHE_OBJECTS = 1<<4,
/// cache shaders loaded via readShader(filename)
CACHE_SHADERS = 1<<5,
/// cache on all read*(filename) calls
CACHE_ALL = CACHE_NODES |
CACHE_IMAGES |
CACHE_HEIGHTFIELDS |
CACHE_ARCHIVES |
CACHE_OBJECTS |
CACHE_SHADERS
};
Options():
osg::Object(true),
_objectCacheHint(CACHE_ARCHIVES) {}
Options(const std::string& str):
osg::Object(true),
_str(str),
_objectCacheHint(CACHE_ARCHIVES) {}
Options(const Options& options,const osg::CopyOp& copyop=osg::CopyOp::SHALLOW_COPY):
osg::Object(options,copyop),
_str(options._str),
_databasePaths(options._databasePaths),
_objectCacheHint(options._objectCacheHint) {}
META_Object(osgDB,Options);
/** Set the general Options string.*/
void setOptionString(const std::string& str) { _str = str; }
/** Get the general Options string.*/
const std::string& getOptionString() const { return _str; }
/** Set the database path to use a hint of where to look when loading models.*/
void setDatabasePath(const std::string& str) { _databasePaths.clear(); _databasePaths.push_back(str); }
/** Get the database path which is used a hint of where to look when loading models.*/
FilePathList& getDatabasePathList() { return _databasePaths; }
/** Get the const database path which is used a hint of where to look when loading models.*/
const FilePathList& getDatabasePathList() const { return _databasePaths; }
/** Set whether the Registry::ObjectCache should be used by default.*/
void setObjectCacheHint(CacheHintOptions useObjectCache) { _objectCacheHint = useObjectCache; }
/** Get whether the Registry::ObjectCache should be used by default.*/
CacheHintOptions getObjectCacheHint() const { return _objectCacheHint; }
/** Sets a plugindata value PluginData with a string */
void setPluginData(const std::string& s, void* v) const { _pluginData[s] = v; }
/** Get a value from the PluginData */
void* getPluginData(const std::string& s) { return _pluginData[s]; }
/** Get a value from the PluginData */
const void* getPluginData(const std::string& s) const
{
PluginDataMap::const_iterator itr = _pluginData.find(s);
return (itr == _pluginData.end()) ? 0 : itr->second;
}
/** Remove a value from the PluginData */
void removePluginData(const std::string& s) const { _pluginData.erase(s); }
protected:
virtual ~Options() {}
std::string _str;
FilePathList _databasePaths;
CacheHintOptions _objectCacheHint;
typedef std::map<std::string,void*> PluginDataMap;
mutable PluginDataMap _pluginData;
};
class OSGDB_EXPORT ReadResult
{
public:
enum ReadStatus
{
FILE_NOT_HANDLED, //!< File is not appropriate for this file reader, due to some incompatibility, but *not* a read error.
FILE_NOT_FOUND, //!< File could not be found or could not be read.
FILE_LOADED, //!< File successfully found, loaded, and converted into osg.
FILE_LOADED_FROM_CACHE, //!< File found in cache and returned.
ERROR_IN_READING_FILE, //!< File found, loaded, but an error was encountered during processing.
FILE_REQUESTED, //!< Asyncronous file read has been requested, but returning immediatiely, keep polling plugin till file read has been completed.
};
ReadResult(ReadStatus status=FILE_NOT_HANDLED):_status(status) {}
ReadResult(const std::string& m):_status(ERROR_IN_READING_FILE),_message(m) {}
ReadResult(osg::Object* obj, ReadStatus status=FILE_LOADED):_status(status),_object(obj) {}
ReadResult(const ReadResult& rr):_status(rr._status),_message(rr._message),_object(rr._object) {}
ReadResult& operator = (const ReadResult& rr) { if (this==&rr) return *this; _status=rr._status; _message=rr._message;_object=rr._object; return *this; }
osg::Object* getObject();
osg::Image* getImage();
osg::HeightField* getHeightField();
osg::Node* getNode();
osgDB::Archive* getArchive();
osg::Shader* getShader();
bool validObject() { return _object.valid(); }
bool validImage() { return getImage()!=0; }
bool validHeightField() { return getHeightField()!=0; }
bool validNode() { return getNode()!=0; }
bool validArchive() { return getArchive()!=0; }
bool validShader() { return getShader()!=0; }
osg::Object* takeObject();
osg::Image* takeImage();
osg::HeightField* takeHeightField();
osg::Node* takeNode();
osgDB::Archive* takeArchive();
osg::Shader* takeShader();
std::string& message() { return _message; }
const std::string& message() const { return _message; }
ReadStatus status() const { return _status; }
bool success() const { return _status==FILE_LOADED || _status==FILE_LOADED_FROM_CACHE ; }
bool loadedFromCache() const { return _status==FILE_LOADED_FROM_CACHE; }
bool error() const { return _status==ERROR_IN_READING_FILE; }
bool notHandled() const { return _status==FILE_NOT_HANDLED; }
bool notFound() const { return _status==FILE_NOT_FOUND; }
protected:
ReadStatus _status;
std::string _message;
osg::ref_ptr<osg::Object> _object;
};
class WriteResult
{
public:
enum WriteStatus
{
FILE_NOT_HANDLED,
FILE_SAVED,
ERROR_IN_WRITING_FILE
};
WriteResult(WriteStatus status=FILE_NOT_HANDLED):_status(status) {}
WriteResult(const std::string& m):_status(ERROR_IN_WRITING_FILE),_message(m) {}
WriteResult(const WriteResult& rr):_status(rr._status),_message(rr._message) {}
WriteResult& operator = (const WriteResult& rr) { if (this==&rr) return *this; _status=rr._status; _message=rr._message; return *this; }
std::string& message() { return _message; }
const std::string& message() const { return _message; }
WriteStatus status() const { return _status; }
bool success() const { return _status==FILE_SAVED; }
bool error() const { return _status==ERROR_IN_WRITING_FILE; }
bool notHandled() const { return _status==FILE_NOT_HANDLED; }
protected:
WriteStatus _status;
std::string _message;
};
enum ArchiveStatus
{
READ,
WRITE,
CREATE
};
/** open an archive for reading, writing, or to create an empty archive for writing to.*/
virtual ReadResult openArchive(const std::string& /*fileName*/,ArchiveStatus, unsigned int =4096, const Options* =NULL) const { return ReadResult(ReadResult::FILE_NOT_HANDLED); }
/** open an archive for reading.*/
virtual ReadResult openArchive(std::istream& /*fin*/,const Options* =NULL) const { return ReadResult(ReadResult::FILE_NOT_HANDLED); }
virtual ReadResult readObject(const std::string& /*fileName*/,const Options* =NULL) const { return ReadResult(ReadResult::FILE_NOT_HANDLED); }
virtual ReadResult readImage(const std::string& /*fileName*/,const Options* =NULL) const { return ReadResult(ReadResult::FILE_NOT_HANDLED); }
virtual ReadResult readHeightField(const std::string& /*fileName*/,const Options* =NULL) const { return ReadResult(ReadResult::FILE_NOT_HANDLED); }
virtual ReadResult readNode(const std::string& /*fileName*/,const Options* =NULL) const { return ReadResult(ReadResult::FILE_NOT_HANDLED); }
virtual ReadResult readShader(const std::string& /*fileName*/,const Options* =NULL) const { return ReadResult(ReadResult::FILE_NOT_HANDLED); }
virtual WriteResult writeObject(const osg::Object& /*obj*/,const std::string& /*fileName*/,const Options* =NULL) const {return WriteResult(WriteResult::FILE_NOT_HANDLED); }
virtual WriteResult writeImage(const osg::Image& /*image*/,const std::string& /*fileName*/,const Options* =NULL) const {return WriteResult(WriteResult::FILE_NOT_HANDLED); }
virtual WriteResult writeHeightField(const osg::HeightField& /*heightField*/,const std::string& /*fileName*/,const Options* =NULL) const {return WriteResult(WriteResult::FILE_NOT_HANDLED); }
virtual WriteResult writeNode(const osg::Node& /*node*/,const std::string& /*fileName*/,const Options* =NULL) const { return WriteResult(WriteResult::FILE_NOT_HANDLED); }
virtual WriteResult writeShader(const osg::Shader& /*shader*/,const std::string& /*fileName*/,const Options* =NULL) const {return WriteResult(WriteResult::FILE_NOT_HANDLED); }
virtual ReadResult readObject(std::istream& /*fin*/,const Options* =NULL) const { return ReadResult(ReadResult::FILE_NOT_HANDLED); }
virtual ReadResult readImage(std::istream& /*fin*/,const Options* =NULL) const { return ReadResult(ReadResult::FILE_NOT_HANDLED); }
virtual ReadResult readHeightField(std::istream& /*fin*/,const Options* =NULL) const { return ReadResult(ReadResult::FILE_NOT_HANDLED); }
virtual ReadResult readNode(std::istream& /*fin*/,const Options* =NULL) const { return ReadResult(ReadResult::FILE_NOT_HANDLED); }
virtual ReadResult readShader(std::istream& /*fin*/,const Options* =NULL) const { return ReadResult(ReadResult::FILE_NOT_HANDLED); }
virtual WriteResult writeObject(const osg::Object& /*obj*/,std::ostream& /*fout*/,const Options* =NULL) const { return WriteResult(WriteResult::FILE_NOT_HANDLED); }
virtual WriteResult writeImage(const osg::Image& /*image*/,std::ostream& /*fout*/,const Options* =NULL) const { return WriteResult(WriteResult::FILE_NOT_HANDLED); }
virtual WriteResult writeHeightField(const osg::HeightField& /*heightField*/,std::ostream& /*fout*/,const Options* =NULL) const { return WriteResult(WriteResult::FILE_NOT_HANDLED); }
virtual WriteResult writeNode(const osg::Node& /*node*/,std::ostream& /*fout*/,const Options* =NULL) const { return WriteResult(WriteResult::FILE_NOT_HANDLED); }
virtual WriteResult writeShader(const osg::Shader& /*shader*/,std::ostream& /*fout*/,const Options* =NULL) const { return WriteResult(WriteResult::FILE_NOT_HANDLED); }
};
}
#endif // OSGDB_READERWRITER