Re: [gsl-dev] replace the .bmp splashscreen

[eric b]

Hi Herbert, all,

Le 15 avr. 09 à 09:07, Herbert Duerr a écrit :

Create a SvFileStream/SvMemoryStream/ etc. (see tools/stream.hxx)
Create a PNGReader for that stream (see vcl/pngread.hxx)
Do a Read() on that PNGReader to get the BitmapEx.

Thorsten Behrens (thanks to him ! ) helped me to understand how to  
play with Streams, and now I got some working code (no more crashes,  
havePng() returns true, and I can verify the Stream is open and  
functionnal), but I need your opinion.

At the beginning, I modified the splash.hxx and the splash.cxx  
accordingly to replace all .bmp with .png equivalents. As summary,  
the current buffer seems to be ok. , but I continue to see nothing,  
and this is certainly my fault.

Probably the problem is caused by  SetBackgroundBitmap( _aIntroBmp );

I replaced in SplashScreen::updateStatus() with :

        Point xtopleft(212,216);
        OutputDevice::DrawBitmapEx (xtopleft, _aIntroPng);

... but I'll debug this part later. Anyway, let's do things  
progressively :-)  :

I have pasted some code (including some comments for my own  
understanding) below, and it would be great to have your opinion, or  
confirmation it looks ok for you ... or needs changes?
As reminder, the real process in the code below involves the  
following methods :  initPng() calling  findPng(), itself calling  
loadBitmap(), and I first had to create the SvStream thing.


Thanks in advance :)
Eric Bachard


Notes:

1) rBmpFileName does contain the .png file name, means ending  
with .png instead of .bmp

2) _aIntroBitmap is of BitmapEx type

3) the dbg_dump() thing is there for debug purpose only.



// ---------  Quote -------------------
std::auto_ptr< SvStream > wrapStream( SvStream & stream )
{
    std::auto_ptr< SvStream > s(new SvMemoryStream);

    // The for loop is there, because we read part by part the  
bitmap datas, and ignore
    // how many rounds we will do, except if we know the exact size  
of the buffer
    // FIXME : stream.GetBufferSize() returns 1024.
    // Is it really efficient to use several times ( png size /  
1024 ) a full 1024 Bytes buffer
    // or one pass of (.png size +1) only (and remove this hackish  
loop...) ?
    for (;;)
    {
        // 84010 is the exact size of the .png in bytes, so we need  
size = 84010 + 1
        // other solution is to use stream.GetBufferSize(), but  
returns 1024 (?)
        // Thorsten suggested 4096 (similar)
        sal_Int32 const size = 84010 + 1;

        //stream.SetBufferSize( size);
        void* data = rtl_allocateMemory( size );

#ifdef DEBUG
        fprintf( stderr, " size = stream.GetBufferSize() returns %ld 
\n", size);
#endif
        // to avoid crashes : stream.Open() before Read() !
        sal_Int32 n = stream.Read(data, size);
        s->Write(data, n);
        // condition of output of the loop : the data have been read  
all
        if (n < size)
            break;
    }
    s->Seek(0);
    return s;
}

bool SplashScreen::loadPng( rtl::OUString const & path, const  
rtl::OUString &rBmpFileName )
{
    if ( rBmpFileName.getLength() == 0 )
        return false;

    INetURLObject aObj( path, INET_PROT_FILE );
    aObj.insertName( rBmpFileName );

#ifdef DEBUG
    fprintf( stderr, " We are in %s\n", __func__ );
    fprintf( stderr, " rBmpFileName contains: %s \n",dbg_dump 
(rtl::OUString(rBmpFileName)));
    fprintf( stderr, " aObj.PathToFileName() contains: %s  
\n",dbg_dump(rtl::OUString(aObj.PathToFileName())));
#endif

   if (aObj.PathToFileName().endsWithAsciiL 
(RTL_CONSTASCII_STRINGPARAM(".png")))
    {
        SvFileStream pStream( aObj.PathToFileName(), STREAM_STD_READ );
        pStream.Open( aObj.PathToFileName(), STREAM_STD_READ  );
        std::auto_ptr< SvStream > s(wrapStream(pStream));

//      probably wrong
//      pStream >> _aIntroPng;

        _aIntroPng = vcl::PNGReader(*s).Read();
        return true;
    }
    else
        return false;
}
// ---------  End Quote -------------------


--
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