Re: [GD-DEVEL] Problems copying PNG with Alpha-Transparency

Hello,

problem solved... I had to use "gdImageCreateTrueColor" to get a nice
result... sorry.
But why is the Background of my Image allways black when I replace
gdImageCreate with gdImageCreateTrueColor?

Best Rgds.
Dieter

Dieter Guthmann schrieb:
> hope 14k for the PNG-File are ok.
> Below the C-Code I've used for generating the attached file. As
> "PNG_transparency_demonstration_1.png" I used the Demonstration-Image
> which you can get here:
>
> <http://de.wikipedia.org/w/index.php?title=Datei:PNG_transparency_demonstration_1.png&filetimestamp=20090422121649>
>
>
> ==========
>   gdImagePtr dest, sourceGd;
>   FILE *pngout, *sourcefile;
>   int white;
>
>   sourcefile = fopen( "PNG_transparency_demonstration_1.png", "rb" );
>   sourceGd = gdImageCreateFromPng( sourcefile );
>   fclose( sourcefile );
>  
>   dest = gdImageCreate( 840, 640 );
>
>   white = gdImageColorAllocate( dest, 255, 255, 255 ); 
>
>   gdImageCopy( dest,
>                sourceGd,
>                20,
>                20,
>                0,
>                0,
>                gdImageSX( sourceGd ),
>                gdImageSY( sourceGd ) );
>  
>   pngout = fopen( "result.png", "wb" );
>  
>   gdImagePngEx( dest, pngout, 9 );
>  
>   fclose( pngout );
>  
>   gdImageDestroy( dest );
>   gdImageDestroy( sourceGd );