X-Git-Url: http://git.shiar.net/sheet.git/blobdiff_plain/bfb80ffa567c24ad151eaad7c0e813eb1f6cbe76..25a210c5de3a4e164a39839dedeb997d56f31faf:/font.plp

diff --git a/font.plp b/font.plp
index 2af6133..8867921 100644
--- a/font.plp
+++ b/font.plp
@@ -16,9 +16,17 @@ if (my $font = $ENV{PATH_INFO} =~ s{^/}{}r) {
 	my ($fontmeta, @cover) = do "ttfsupport/$font.inc.pl";
 	$fontmeta or die "Unknown font $font\n";
 
-	my $offset = $get{q} || 0;
-	$offset < 0 and $offset = 0;
+	require Unicode::UCD;
+
 	my $size = 0x200;
+	my $offset = eval {
+		local $_ = $get{q} || 0;
+		return $_ if /\A\d+\z/;  # numeric
+		return hex $1 if /\A (?: 0?x | u\W* ) ([0-9a-f]+) \z/ix;  # hexadecimal
+		return $_->[0]->[0] for Unicode::UCD::charblock(ucfirst) || ();  # block
+		die "Unknown offset query '$_'\n";
+	};
+	die $@ if $@;
 
 	say "<h1>Font coverage</h1>";
 	say "<h2>$_</h2>" for EscapeHTML($fontmeta->{name});