From 655586fe5e1fadf2a2ef7826e61ee9a445ffa37a Mon Sep 17 00:00:00 2001
From: Behdad Esfahbod <behdad@behdad.org>
Date: Thu, 21 Jul 2011 00:51:18 -0400
Subject: [PATCH] Towards normalization

---
 src/Makefile.am              |  1 +
 src/hb-ot-shape-normalize.cc | 71 ++++++++++++++++++++++++++++++++++++++++++++
 src/hb-ot-shape-private.hh   | 12 ++++++++
 src/hb-ot-shape.cc           | 10 ++-----
 4 files changed, 86 insertions(+), 8 deletions(-)
 create mode 100644 src/hb-ot-shape-normalize.cc

diff --git a/src/Makefile.am b/src/Makefile.am
index 4bff997..2692d33 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -60,6 +60,7 @@ HBSOURCES += \
 	hb-ot-shape-complex-indic-table.hh \
 	hb-ot-shape-complex-misc.cc \
 	hb-ot-shape-complex-private.hh \
+	hb-ot-shape-normalize.cc \
 	hb-ot-shape-private.hh \
 	hb-ot-tag.cc \
 	$(NULL)
diff --git a/src/hb-ot-shape-normalize.cc b/src/hb-ot-shape-normalize.cc
new file mode 100644
index 0000000..6d55a30
--- /dev/null
+++ b/src/hb-ot-shape-normalize.cc
@@ -0,0 +1,71 @@
+/*
+ * Copyright © 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
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ * Google Author(s): Behdad Esfahbod
+ */
+
+#include "hb-ot-shape-private.hh"
+
+HB_BEGIN_DECLS
+
+static void
+handle_single_char_cluster (hb_ot_shape_context_t *c,
+			    unsigned int i)
+{
+  hb_buffer_t *b = c->buffer;
+  hb_codepoint_t glyph;
+
+  if (hb_font_get_glyph (c->font, b->info[i].codepoint, 0, &glyph))
+    return;
+
+  /* Decompose */
+}
+
+static void
+handle_multi_char_cluster (hb_ot_shape_context_t *c,
+			   unsigned int i,
+			   unsigned int end)
+{
+  /* If there's a variation-selector, give-up, it's just too hard. */
+}
+
+void
+_hb_normalize (hb_ot_shape_context_t *c)
+{
+  hb_buffer_t *b = c->buffer;
+  
+  unsigned int count = b->len;
+  for (unsigned int i = 0; i < count;) {
+    unsigned int end;
+    for (end = i + 1; end < count; end++)
+      if (b->info[i].cluster != b->info[end].cluster)
+        break;
+    if (i + 1 == end)
+      handle_single_char_cluster (c, i);
+    else
+      handle_multi_char_cluster (c, i, end);
+    i = end;
+  }
+}
+
+HB_END_DECLS
diff --git a/src/hb-ot-shape-private.hh b/src/hb-ot-shape-private.hh
index 307784d..d64178a 100644
--- a/src/hb-ot-shape-private.hh
+++ b/src/hb-ot-shape-private.hh
@@ -91,6 +91,18 @@ struct hb_ot_shape_context_t
 };
 
 
+static inline hb_bool_t
+is_variation_selector (hb_codepoint_t unicode)
+{
+  return unlikely ((unicode >=  0x180B && unicode <=  0x180D) || /* MONGOLIAN FREE VARIATION SELECTOR ONE..THREE */
+		   (unicode >=  0xFE00 && unicode <=  0xFE0F) || /* VARIATION SELECTOR-1..16 */
+		   (unicode >= 0xE0100 && unicode <= 0xE01EF));  /* VARIATION SELECTOR-17..256 */
+}
+
+
+HB_INTERNAL void _hb_normalize (hb_ot_shape_context_t *c);
+
+
 HB_END_DECLS
 
 #endif /* HB_OT_SHAPE_PRIVATE_HH */
diff --git a/src/hb-ot-shape.cc b/src/hb-ot-shape.cc
index 2abcb9e..306beb3 100644
--- a/src/hb-ot-shape.cc
+++ b/src/hb-ot-shape.cc
@@ -176,14 +176,6 @@ hb_ot_position_complex (hb_ot_shape_context_t *c)
 
 /* Prepare */
 
-static inline hb_bool_t
-is_variation_selector (hb_codepoint_t unicode)
-{
-  return unlikely ((unicode >=  0x180B && unicode <=  0x180D) || /* MONGOLIAN FREE VARIATION SELECTOR ONE..THREE */
-		   (unicode >=  0xFE00 && unicode <=  0xFE0F) || /* VARIATION SELECTOR-1..16 */
-		   (unicode >= 0xE0100 && unicode <= 0xE01EF));  /* VARIATION SELECTOR-17..256 */
-}
-
 static void
 hb_set_unicode_props (hb_ot_shape_context_t *c)
 {
@@ -373,6 +365,8 @@ hb_ot_shape_execute_internal (hb_ot_shape_context_t *c)
 
   hb_form_clusters (c);
 
+  _hb_normalize (c);
+
   hb_ot_shape_setup_masks (c); /* BUFFER: Clobbers var2 */
 
   /* SUBSTITUTE */
-- 
2.7.4