libpng14 error

This is probably already known, but I'll go ahead and post it. In trying to build against libpng-1.4.0, I had to edit src/_png.cpp:

// png_destroy_read_struct(&png_ptr, &info_ptr, png_infopp_NULL);
   png_destroy_read_struct(&png_ptr, &info_ptr, NULL);


Thanks for reporting this. I wasn't aware of the issue.

Since I don't have a libpng-1.4 to verify the fix with, are you able to checkout from SVN trunk and test it?