[Gtkradiant] [Bug 684] Cleanup pnp NULL Typecasts in plugins/imagepng/plugin.cpp

[gtkradiant@zerowing.idsoftware.com]

http://zerowing.idsoftware.com/bugzilla/show_bug.cgi?id=684





------- Additional Comments From michael@johalla.de  2003-04-14 14:44 -------
libpng_1.0.12 from debian woody misses png_infopp_NULL and png_voidp_NULL too
but later versions are working (libpng12-0-dev and libpng3-dev). I don't think
"pkg-config" could fix that issue. Maybe we can include the missing lines from
png.h:

#ifndef png_voidp_NULL
#define png_voidp_NULL            (png_voidp)NULL
#endif
#ifndef png_infopp_NULL
#define png_infopp_NULL           (png_infopp)NULL
#endif