1 files changed, 20 insertions, 5 deletions
diff --git a/Master/texmf-dist/omega/otp/uni2char/oututf8.otp b/Master/texmf-dist/omega/otp/uni2char/oututf8.otp
index cb4d971f533..bc1ddd617fa 100644
--- a/Master/texmf-dist/omega/otp/uni2char/oututf8.otp
+++ b/Master/texmf-dist/omega/otp/uni2char/oututf8.otp
@@ -1,7 +1,7 @@
-
 % File oututf8.otp
-% Conversion to UTF-8 from Unicode
+% Conversion to UTF-8 from UTF-16
 % Copyright (c) 1999 John Plaice and Yannis Haralambous
+% Copyright (C) 2005, 2006 Roozbeh Pournader
 % This file is part of the Omega project.
 %
 
@@ -10,13 +10,28 @@ output: 1;
 
 expressions:
 
-@"00-@"7F
+% One-byte sequences get mapped to proper ASCII
+@"0000-@"007F
   => \1;
-@"80-@"7FF
+
+% Two-byte sequences
+@"0080-@"07FF
   => #((\1 div: @"40)+@"C0)
      #((\1 mod: @"40)+@"80);
-@"800-@"FFFF
+
+% Three-byte sequences
+(@"0800-@"D7FF|@"E000-@"FFFF)
   => #((\1 div: @"1000)+@"E0)
      #(((\1 mod: @"1000) div: @"40)+@"80)
      #((\1 mod: @"40)+@"80);
+
+% Surrogate pairs, which make four-byte sequences:
+(@"D800-@"DBFF)(@"DC00-@"DFFF)
+  => #(((((\1 mod: @"400) div: 4)+@"10) div: @"40)+@"F0)
+     #(((((\1 mod: @"400) div: 4)+@"10) mod: @"40)+@"80)
+     #(((\1 mod: 4)*@"10) +((\2 mod: @"400) div: @"40)+@"80)
+     #((\2 mod: @"40)+@"80);
+
+% Anything else gets mapped to 0x00. This should probably
+% get replaced by an error message, instead.
 . => #(@"00);