1 files changed, 42 insertions, 0 deletions
diff --git a/text2screen.pl b/text2screen.pl
new file mode 100644
index 0000000..7dc2e52
--- /dev/null
+++ b/text2screen.pl
@@ -0,0 +1,42 @@
+#!/usr/bin/perl -w
+
+# Turn each line of stdin into one 40-byte line of Atari screen codes,
+# truncating or padding with nulls as needed.
+
+# Input format is plain text, except any character can be preceded
+# by a \ to inverse it. No way to get a non-inverse \ in there, sorry.
+# %V will be replaced by the contents of the VERSION file.
+
+use bytes;
+
+$linelen = $1 || 40; # 40 for normal playfield.
+
+chomp($ver = `cat VERSION`);
+
+while(<>) {
+	chomp;
+
+	s/%V/$ver/;
+	s/\\(.)/chr(ord($1)|0x80)/ge;
+
+	if(length > $linelen) {
+		warn "$0: line $. truncated to $linelen characters!\n";
+		substr($_, $linelen) = "";
+	}
+
+	my $blanks = $linelen;
+	for(map { ord } split "", $_) {
+		my $byte = $_ & 0x7f;
+		my $inv =  $_ & 0x80;
+#warn sprintf("\$_ %02x, \$byte %02x, \$inv %02x", $_, $byte, $inv);
+		if($byte < 32) {
+			$byte += 64;
+		} elsif($byte >= 32 && $byte <= 96) {
+			$byte -= 32;
+		}
+#warn sprintf("result: %02x", ($byte | $inv));
+		print chr($byte | $inv);
+		$blanks--;
+	}
+	print chr(0) x $blanks;
+}