commit e7fb216ad8f65ee4d451a0c3e698dfafd7cf2436
author Behdad Esfahbod <behdad@behdad.org> Wed May 21 19:08:39 2014 -0400
committer Behdad Esfahbod <behdad@behdad.org> Wed May 21 19:14:03 2014 -0400
tree d843ea78bc3c0b3fae52ae9846fdf9e8ab144ccc
parent 4c777d3465d16db968dc3f58a1f30444eed732a3

Fix cmap subtable format 4 compiling

Was failing all these years, if a idDelta value happened to be
exactly -0x8000...

Test case: roundtripping MTLmr3m.ttf.

Lib/fontTools/ttLib/tables/_c_m_a_p.py

diff --git a/Lib/fontTools/ttLib/tables/_c_m_a_p.py b/Lib/fontTools/ttLib/tables/_c_m_a_p.py
index 3398a88..9dea010 100644
--- a/Lib/fontTools/ttLib/tables/_c_m_a_p.py
+++ b/Lib/fontTools/ttLib/tables/_c_m_a_p.py
@@ -712,7 +712,7 @@
 
 		if idDelta > 0x7FFF:
 			idDelta = idDelta - 0x10000
-		elif idDelta <  -0x7FFF:
+		elif idDelta <  -0x8000:
 			idDelta = idDelta + 0x10000
 
 		return idDelta