From Wang Rui, "I have just done some changes on the classic osgdb_gif plugin (based on OSG 2.5.0). I wish our developers may use the newly written GIF reading plugin to attach animate GIF files as textures now! In my opinion, a GIF is much smaller than AVI and MOVs, and much more efficient sometimes.

Changes includes:
1. A new GifImageStream class (inherit from osg::ImageStream and OpenThreads::Thread) have already been added to implement different operations of a GIF movie, such like playing, pausing, rewinding, setting time and so on.
2. Some small changes to decode_row() and gif_read_stream(), which make the transparency of GIF images correctly.
3. Just a few changes to the ReaderWriterGIF::readGIFStream() function, which ensure that animate GIFs are loaded by GifImageStream (and the function returns GifImageStream objects) and static GIFs unchanged (still use the old method and returns osg::Image objects!).
 
Attachments are the cpp file and an animate GIF file for further test. Just rebuild the osgdb_gif project and use osgviewer or osgmovie to view it.
The plugin has been tested on Windows and Arch Linux."
This commit is contained in:
Robert Osfield 2008-05-27 10:50:26 +00:00
parent 476cb5373e
commit 66a1996a5a

View File

@ -1,4 +1,5 @@
#include <osg/Image>
#include <osg/ImageStream>
#include <osg/Notify>
#include <osg/Geode>
#include <osg/GL>
@ -7,6 +8,8 @@
#include <osgDB/FileUtils>
#include <osgDB/Registry>
#include <OpenThreads/Thread>
/****************************************************************************
*
@ -57,6 +60,204 @@ extern "C"
#define MY_GIF_DEBUG 1
// GifImageStream class
class GifImageStream : public osg::ImageStream, public OpenThreads::Thread
{
public:
GifImageStream()
: _length(0), _dataNum(0), _frameNum(0),
_done(false), _currentLength(0), _multiplier(1.0),
osg::ImageStream() { _status=PAUSED; }
virtual Object* clone() const { return new GifImageStream; }
virtual bool isSameKindAs( const Object* obj ) const
{ return dynamic_cast<const GifImageStream*>(obj) != NULL; }
virtual const char* className() const { return "GifImageStream"; }
virtual void play()
{
if (!isRunning())
start();
_status=PLAYING;
}
virtual void pause() { _status=PAUSED; }
virtual void rewind() { setReferenceTime( 0.0 ); }
virtual void quit( bool waitForThreadToExit=true )
{
_done = true;
if ( waitForThreadToExit )
{
while( isRunning() )
OpenThreads::Thread::YieldCurrentThread();
osg::notify(osg::DEBUG_INFO)<<"GifImageStream thread quitted"<<std::endl;
}
}
StreamStatus getStatus() { return _status; }
virtual double getLength() const { return _length*0.01*_multiplier; }
// Go to a specific position of stream
virtual void setReferenceTime( double time )
{
OpenThreads::ScopedLock<OpenThreads::Mutex> lock(_mutex);
int i=1;
int framePos = static_cast<int>(time*100.0/_multiplier);
if ( framePos>=(int)_length )
framePos = _length;
std::vector<FrameData*>::iterator it;
for ( it=_dataList.begin(); it!=_dataList.end(); it++,i++ )
{
framePos -= (*it)->delay;
if ( framePos<0 )
break;
}
_dataNum = i-1;
_frameNum = (*it)->delay+framePos;
setNewImage();
}
virtual double getReferenceTime() const { return _currentLength*0.01*_multiplier; }
// Speed up, slow down or back to normal (1.0)
virtual void setTimeMultiplier( double m )
{
OpenThreads::ScopedLock<OpenThreads::Mutex> lock(_mutex);
if ( m>0 )
_multiplier = m;
}
virtual double getTimeMultiplier() const { return _multiplier; }
// Not used in GIF animation
virtual void setVolume(float) {}
virtual float getVolume() const { return 0.0f; }
virtual void run()
{
_dataIter = _dataList.begin();
while ( !_done )
{
if ( _status==PLAYING && (*_dataIter) )
{
if ( _frameNum>=(*_dataIter)->delay )
{
_frameNum = 0;
if ( _dataNum>=_dataList.size()-1 )
{
if ( getLoopingMode()==LOOPING )
{
_dataNum = 0;
_currentLength = 0;
}
}
else
_dataNum++;
setNewImage();
}
else
{
_frameNum++;
_currentLength++;
}
OpenThreads::Thread::microSleep(static_cast<int>(10000.0f*_multiplier));
}
else
OpenThreads::Thread::microSleep(150000L);
}
}
void addToImageStream( int ss, int tt, int rr, int numComponents, int delayTime, unsigned char* imgData )
{
if ( isRunning() )
{
osg::notify(osg::WARN)<<"GifImageStream::addToImageStream: thread is running!"<<std::endl;
return;
}
_s = ss;
_t = tt;
_r = rr;
_internalFormat = numComponents;
_dataType = GL_UNSIGNED_BYTE;
_pixelFormat =
numComponents == 1 ? GL_LUMINANCE :
numComponents == 2 ? GL_LUMINANCE_ALPHA :
numComponents == 3 ? GL_RGB :
numComponents == 4 ? GL_RGBA : (GLenum)-1;
if ( _dataList.empty() )
{
// Set image texture for the first time
setImage(_s,_t,_r,_internalFormat,_pixelFormat,_dataType,
imgData,osg::Image::NO_DELETE,1);
}
FrameData* newData = new FrameData;
newData->delay = delayTime;
newData->data = imgData;
_dataList.push_back( newData );
_length += delayTime;
}
protected:
typedef struct
{
unsigned int delay;
unsigned char* data;
} FrameData;
void setNewImage()
{
_dataIter = _dataList.begin()+_dataNum;
if ( *_dataIter )
{
unsigned char* image = (*_dataIter)->data;
setImage(_s,_t,_r,_internalFormat,_pixelFormat,_dataType,
image,osg::Image::NO_DELETE,1);
dirty();
}
}
virtual ~GifImageStream()
{
if( isRunning() )
quit( true );
std::vector<FrameData*>::iterator it;
for ( it=_dataList.begin(); it!=_dataList.end(); it++ )
{
delete (*it)->data;
delete (*it);
}
}
double _multiplier;
unsigned int _currentLength;
unsigned int _length;
unsigned int _frameNum;
unsigned int _dataNum;
std::vector<FrameData*> _dataList;
std::vector<FrameData*>::iterator _dataIter;
int _s;
int _t;
int _r;
int _internalFormat;
unsigned int _pixelFormat;
unsigned int _dataType;
bool _done;
OpenThreads::Mutex _mutex;
};
static int giferror = ERR_NO_ERROR;
int
@ -116,18 +317,28 @@ int transparent)
col = *rowdata++;
/* just in case */
if (col >= colormapsize) col = 0;
cmentry = colormap ? &colormap->Colors[col] : NULL;
if (cmentry)
if ( col == transparent )
{
*ptr++ = cmentry->Red;
*ptr++ = cmentry->Green;
*ptr++ = cmentry->Blue;
// keep pixels of last image if transparent mode is on
// this is necessary for GIF animating
ptr += 3;
}
else
{
*ptr++ = col;
*ptr++ = col;
*ptr++ = col;
cmentry = colormap ? &colormap->Colors[col] : NULL;
if (cmentry)
{
*ptr++ = cmentry->Red;
*ptr++ = cmentry->Green;
*ptr++ = cmentry->Blue;
}
else
{
*ptr++ = col;
*ptr++ = col;
*ptr++ = col;
}
}
*ptr++ = (col == transparent ? 0x00 : 0xff);
}
@ -144,13 +355,14 @@ unsigned char *
simage_gif_load(std::istream& fin,
int *width_ret,
int *height_ret,
int *numComponents_ret)
int *numComponents_ret,
GifImageStream** obj)
{
int i, j, n, row, col, width, height, extcode;
unsigned char * rowdata;
unsigned char * buffer, * ptr;
unsigned char bg;
int transparent;
int transparent, delaytime;
GifRecordType recordtype;
GifByteType * extension;
GifFileType * giffile;
@ -168,6 +380,7 @@ int *numComponents_ret)
}
transparent = -1; /* no transparent color by default */
delaytime = 8; /* delay time of a frame */
n = giffile->SHeight * giffile->SWidth;
buffer = new unsigned char [n * 4];
@ -210,6 +423,7 @@ int *numComponents_ret)
}
/* Scan the content of the GIF file and load the image(s) in: */
int gif_num=0;
do
{
if (DGifGetRecordType(giffile, &recordtype) == GIF_ERROR)
@ -222,6 +436,16 @@ int *numComponents_ret)
switch (recordtype)
{
case IMAGE_DESC_RECORD_TYPE:
/* start recording image stream if more than one image found */
gif_num++;
if ( gif_num==2 )
{
*obj = new GifImageStream;
(*obj)->addToImageStream( giffile->SWidth, giffile->SHeight, 1, 4, delaytime, buffer );
unsigned char* destbuffer = new unsigned char [n * 4];
buffer = (unsigned char*)memcpy( destbuffer, buffer, n*4 );
}
if (DGifGetImageDesc(giffile) == GIF_ERROR)
{
giferror = ERR_READ;
@ -229,7 +453,7 @@ int *numComponents_ret)
delete [] rowdata;
return NULL;
}
/* subimage position in composite image */
/* subimage position in composite image */
row = giffile->Image.Top;
col = giffile->Image.Left;
width = giffile->Image.Width;
@ -277,6 +501,16 @@ int *numComponents_ret)
else decode_row(giffile, buffer, rowdata, col, row, width, transparent);
}
}
// Record gif image stream
if ( *obj && obj )
{
(*obj)->addToImageStream( giffile->SWidth, giffile->SHeight, 1, 4, delaytime, buffer );
unsigned char* destbuffer = new unsigned char [n * 4];
buffer = (unsigned char*)memcpy( destbuffer, buffer, n*4 );
}
break;
case EXTENSION_RECORD_TYPE:
/* Skip any extension blocks in file: */
@ -292,6 +526,8 @@ int *numComponents_ret)
{
if (extension[0] >= 4 && extension[1] & 0x1) transparent = extension[4];
else transparent = -1;
delaytime = (extension[3]<<8)+extension[2]; // minimum unit 1/100s, so 8 here means 8/100s
}
while (extension != NULL)
{
@ -336,7 +572,8 @@ class ReaderWriterGIF : public osgDB::ReaderWriter
int height_ret;
int numComponents_ret;
imageData = simage_gif_load(fin,&width_ret,&height_ret,&numComponents_ret);
GifImageStream* gifStream = NULL;
imageData = simage_gif_load( fin,&width_ret,&height_ret,&numComponents_ret, &gifStream );
switch (giferror)
{
@ -348,6 +585,13 @@ class ReaderWriterGIF : public osgDB::ReaderWriter
return ReadResult("GIF loader: Out of memory error");
}
// Use GifImageStream to display animate GIFs
if ( gifStream )
{
osg::notify(osg::DEBUG_INFO)<<"Using GifImageStream ..."<<std::endl;
return gifStream;
}
if (imageData==NULL) return ReadResult::FILE_NOT_HANDLED;
int s = width_ret;