OpenSceneGraph/include/osgDB/ImagePager
2008-07-23 19:04:46 +00:00

153 lines
4.4 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_IMAGEPAGER
#define OSGDB_IMAGEPAGER 1
#include <osg/Image>
#include <osg/NodeVisitor>
#include <osg/observer_ptr>
#include <osg/OperationThread>
#include <OpenThreads/Mutex>
#include <osgDB/ReaderWriter>
namespace osgDB
{
class OSGDB_EXPORT ImagePager : public osg::NodeVisitor::ImageRequestHandler
{
public:
ImagePager();
// forward declare
struct RequestQueue;
struct ImageRequest : public osg::Referenced
{
ImageRequest():
osg::Referenced(true),
_timeToMergeBy(0.0) {}
double _timeToMergeBy;
std::string _fileName;
osg::ref_ptr<ReaderWriter::Options> _loadOptions;
osg::observer_ptr<osg::Object> _objectToAttachTo;
osg::ref_ptr<osg::Image> _loadedImage;
RequestQueue* _requestQueue;
};
struct RequestQueue : public osg::Referenced
{
typedef std::vector< osg::ref_ptr<ImageRequest> > RequestList;
void sort();
RequestList _requestList;
OpenThreads::Mutex _requestMutex;
};
struct ReadQueue : public RequestQueue
{
ReadQueue(ImagePager* pager, const std::string& name);
void block() { _block->block(); }
void release() { _block->release(); }
void updateBlock()
{
_block->set((!_requestList.empty() || !_pager->_databasePagerThreadPaused));
}
void clear();
void add(ImageRequest* imageRequest);
void takeFirst(osg::ref_ptr<ImageRequest>& databaseRequest);
osg::ref_ptr<osg::RefBlock> _block;
ImagePager* _pager;
std::string _name;
};
class OSGDB_EXPORT ImageThread : public osg::Referenced, public OpenThreads::Thread
{
public:
enum Mode
{
HANDLE_ALL_REQUESTS,
HANDLE_NON_HTTP,
HANDLE_ONLY_HTTP
};
ImageThread(ImagePager* pager, Mode mode, const std::string& name);
ImageThread(const ImageThread& dt, ImagePager* pager);
void setDone(bool done) { _done = done; }
bool getDone() const { return _done; }
virtual int cancel();
virtual void run();
protected:
virtual ~ImageThread();
bool _done;
Mode _mode;
ImagePager* _pager;
std::string _name;
};
virtual void requestImageFile(const std::string& fileName,osg::Object* attachmentPoint, double timeToMergeBy, const osg::FrameStamp* framestamp);
/** Return true if there are pending updates to the scene graph that require a call to updateSceneGraph(double). */
virtual bool requiresUpdateSceneGraph() const;
/** Merge the changes to the scene graph. */
virtual void updateSceneGraph(double currentFrameTime);
int cancel();
public:
virtual ~ImagePager();
OpenThreads::Mutex _run_mutex;
bool _startThreadCalled;
bool _done;
bool _databasePagerThreadPaused;
osg::ref_ptr<ReadQueue> _readQueue;
osg::ref_ptr<ImageThread> _imageThread;
};
}
#endif