Roll harfbuzz-ng 3b8fd9c48f4bde368bf2d465c148b9743a9216ee

third_party/harfbuzz-ng/src/hb-unicode.cc

 /*
  * Copyright © 2009  Red Hat, Inc.
  * Copyright © 2011 Codethink Limited
  * Copyright © 2010,2011  Google, Inc.
  *
  *  This is part of HarfBuzz, a text shaping library.
  *
  * Permission is hereby granted, without written agreement and without
  * license or royalty fees, to use, copy, modify, and distribute this
  * software and its documentation for any purpose, provided that the
@@ skipping 67 matching lines @@
   return HB_SCRIPT_UNKNOWN;
 }
 
 static hb_bool_t
 hb_unicode_compose_nil (hb_unicode_funcs_t *ufuncs    HB_UNUSED,
                         hb_codepoint_t      a         HB_UNUSED,
                         hb_codepoint_t      b         HB_UNUSED,
                         hb_codepoint_t     *ab        HB_UNUSED,
                         void               *user_data HB_UNUSED)
 {
-  /* TODO handle Hangul jamo here? */
   return FALSE;
 }
 
 static hb_bool_t
 hb_unicode_decompose_nil (hb_unicode_funcs_t *ufuncs    HB_UNUSED,
                           hb_codepoint_t      ab        HB_UNUSED,
                           hb_codepoint_t     *a         HB_UNUSED,
                           hb_codepoint_t     *b         HB_UNUSED,
                           void               *user_data HB_UNUSED)
 {
-  /* TODO handle Hangul jamo here? */
   return FALSE;
 }
 
 
 hb_unicode_funcs_t _hb_unicode_funcs_nil = {
   HB_OBJECT_HEADER_STATIC,
 
   NULL, /* parent */
   TRUE, /* immutable */
   {
@@ skipping 154 matching lines @@
 hb_bool_t
 hb_unicode_decompose (hb_unicode_funcs_t *ufuncs,
                       hb_codepoint_t      ab,
                       hb_codepoint_t     *a,
                       hb_codepoint_t     *b)
 {
   *a = ab; *b = 0;
   return ufuncs->func.decompose (ufuncs, ab, a, b, ufuncs->user_data.decompose);
 }
 
+
+
+unsigned int
+_hb_unicode_modified_combining_class (hb_unicode_funcs_t *ufuncs,
+                                      hb_codepoint_t      unicode)
+{
+  int c = hb_unicode_combining_class (ufuncs, unicode);
+
+  if (unlikely (hb_in_range<int> (c, 27, 33)))
+  {
+    /* Modify the combining-class to suit Arabic better.  See:
+     * http://unicode.org/faq/normalization.html#8
+     * http://unicode.org/faq/normalization.html#9
+     */
+    c = c == 33 ? 27 : c + 1;
+  }
+  else if (unlikely (hb_in_range<int> (c, 10, 25)))
+  {
+    /* The equivalent fix for Hebrew is more complex.
+     *
+     * We permute the "fixed-position" classes 10-25 into the order
+     * described in the SBL Hebrew manual:
+     *
+     * http://www.sbl-site.org/Fonts/SBLHebrewUserManual1.5x.pdf
+     *
+     * (as recommended by:
+     *  http://forum.fontlab.com/archive-old-microsoft-volt-group/vista-and-diacritic-ordering-t6751.0.html)
+     *
+     * More details here:
+     * https://bugzilla.mozilla.org/show_bug.cgi?id=662055
+     */
+    static const int permuted_hebrew_classes[25 - 10 + 1] = {
+      /* 10 sheva */        22,
+      /* 11 hataf segol */  15,
+      /* 12 hataf patah */  16,
+      /* 13 hataf qamats */ 17,
+      /* 14 hiriq */        23,
+      /* 15 tsere */        18,
+      /* 16 segol */        19,
+      /* 17 patah */        20,
+      /* 18 qamats */       21,
+      /* 19 holam */        14,
+      /* 20 qubuts */       24,
+      /* 21 dagesh */       12,
+      /* 22 meteg */        25,
+      /* 23 rafe */         13,
+      /* 24 shin dot */     10,
+      /* 25 sin dot */      11,
+    };
+    c = permuted_hebrew_classes[c - 10];
+  }
+
+  return c;
+}
+