$is_good ? $white : $black += 1;
Yes, to someone who doesn't know the precedence table this is confusing. To someone that doesn't know any Perl I'm sure that the Howdy World program is confusing too. The solution is not to document every line in painful detail as to what exactly is going on so that people that don't know Perl can read your program.
The solution is that programmers learn the precedence table and soon what seemed like a cryptic and convoluted expression will magically transform into an obvious sequence of calculations.