Introduce src dir.

[librarian.git] / src / librarian / font-optimizer / Font / Subsetter / create-data.pl

diff --git a/src/librarian/font-optimizer/Font/Subsetter/create-data.pl b/src/librarian/font-optimizer/Font/Subsetter/create-data.pl
new file mode 100644 (file)
index 0000000..e0a38fb
--- /dev/null
+++ b/src/librarian/font-optimizer/Font/Subsetter/create-data.pl
@@ -0,0 +1,100 @@
+use strict;
+use warnings;
+
+use Unicode::Normalize;
+
+print <<EOF;
+package Font::Subsetter::NormalizationData;
+use strict;
+use warnings;
+our \@data = (
+EOF
+
+# Output is:
+#  [x, a,b,c...],
+# where the codepoint x is the NFC normalization of the string a,b,c
+
+my @data;
+
+open my $f, '/usr/lib/perl5/5.8.8/unicore/UnicodeData.txt' or die $!;
+while (<$f>) {
+    my @c = split /;/, $_;
+    # Find characters which canonically decompose (without any
+    # compatibility tag "<foo>")
+    next unless $c[5] and $c[5] !~ /^</;
+
+    {
+        # Print the character and its maximally-decomposed codepoints,
+        # if they re-compose into it
+        my @x = split //, Unicode::Normalize::NFD(chr hex $c[0]);
+        push @data, [hex $c[0], map ord, @x]
+            if Unicode::Normalize::NFC(join '', @x) eq chr hex $c[0];
+    }
+
+    # Try to find all other strings that can become this character under NFC:
+    # If the maximal decomposition is "abc", we might want the strings
+    # "NFC(ab) c", "NFC(ac) b", etc, so attempt all permutations of abc
+    # and then try all groupings to apply NFC to
+    
+    my @norm = split //, Unicode::Normalize::NFD(chr hex $c[0]);
+    if (@norm == 3) {
+        my ($a, $b, $c) = @norm;
+        for my $cs (permut([$a, $b, $c], [])) { # all permutations
+            for my $cs2 ('ab c', 'a bc') { # all groupings
+                my @x = map Unicode::Normalize::NFC($_), map { s/(.)/$cs->[ord($1)-ord('a')]/eg; $_ } split / /, $cs2;
+                # If NFC didn't collapse everything into single characters, this string is not interesting
+                next if grep length != 1, @x;
+                # If the string doesn't NFC into the desired character, it's not interesting
+                next unless Unicode::Normalize::NFC(join '', @x) eq chr hex $c[0];
+                # This string is good
+                push @data, [hex $c[0], map ord, @x];
+            }
+        }
+    } elsif (@norm == 4) {
+        my ($a, $b, $c, $d) = @norm;
+        for my $cs (permut([$a, $b, $c, $d], [])) {
+            for my $cs2 ('ab c d', 'a bc d', 'a b cd', 'ab cd', 'abc d', 'a bcd') {
+                my @x = map Unicode::Normalize::NFC($_), map { s/(.)/$cs->[ord($1)-ord('a')]/eg; $_ } split / /, $cs2;
+                next if grep length != 1, @x;
+                next unless Unicode::Normalize::NFC(join '', @x) eq chr hex $c[0];
+                push @data, [hex $c[0], map ord, @x];
+            }
+        }
+    } elsif (@norm > 4) {
+        die "\@norm too big";
+    }
+}
+
+print uniq(map "[".join(',', @$_)."],\n", @data);
+
+print <<EOF;
+);
+
+1;
+EOF
+
+sub permut {
+    my @r;
+    my @head = @{ $_[0] };
+    my @tail = @{ $_[1] };
+    unless (@head) {
+        push @r, \@tail;
+    } else {
+        for my $i (0 .. $#head) {
+            my @newhead = @head;
+            my @newtail = @tail;
+            unshift(@newtail, splice(@newhead, $i, 1));
+            push @r, permut([@newhead], [@newtail]);
+        }
+    }
+    return @r;
+}
+
+sub uniq {
+    my @u;
+    my %u;
+    for (@_) {
+        push @u, $_ unless $u{$_}++;
+    }
+    @u;
+}