From 5c6f5982d78e2d7fadc2fbb8b4f3a4be9420c59a Mon Sep 17 00:00:00 2001
From: Behdad Esfahbod <behdad@behdad.org>
Date: Thu, 21 Jul 2011 11:31:08 -0400
Subject: [PATCH] Towards normalization

---
 src/hb-ot-shape-normalize.cc | 33 ++++++++++++++++++++++-----------
 src/hb-ot-shape-private.hh   |  3 ++-
 src/hb-ot-shape.cc           |  4 +++-
 3 files changed, 27 insertions(+), 13 deletions(-)

diff --git a/src/hb-ot-shape-normalize.cc b/src/hb-ot-shape-normalize.cc
index 6d55a30..f6e962c 100644
--- a/src/hb-ot-shape-normalize.cc
+++ b/src/hb-ot-shape-normalize.cc
@@ -28,32 +28,41 @@
 
 HB_BEGIN_DECLS
 
-static void
-handle_single_char_cluster (hb_ot_shape_context_t *c,
-			    unsigned int i)
+static bool
+get_glyph (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;
+  return hb_font_get_glyph (c->font, b->info[i].codepoint, 0, &b->info[i].intermittent_glyph());
+}
+
+static bool
+handle_single_char_cluster (hb_ot_shape_context_t *c,
+			    unsigned int i)
+{
+  if (get_glyph (c, i))
+    return FALSE;
 
   /* Decompose */
+
+  return FALSE;
 }
 
-static void
+static bool
 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. */
+  return FALSE;
 }
 
-void
+bool
 _hb_normalize (hb_ot_shape_context_t *c)
 {
   hb_buffer_t *b = c->buffer;
-  
+  bool changed = FALSE;
+
   unsigned int count = b->len;
   for (unsigned int i = 0; i < count;) {
     unsigned int end;
@@ -61,11 +70,13 @@ _hb_normalize (hb_ot_shape_context_t *c)
       if (b->info[i].cluster != b->info[end].cluster)
         break;
     if (i + 1 == end)
-      handle_single_char_cluster (c, i);
+      changed |= handle_single_char_cluster (c, i);
     else
-      handle_multi_char_cluster (c, i, end);
+      changed |= handle_multi_char_cluster (c, i, end);
     i = end;
   }
+
+  return changed;
 }
 
 HB_END_DECLS
diff --git a/src/hb-ot-shape-private.hh b/src/hb-ot-shape-private.hh
index d64178a..03dd4ed 100644
--- a/src/hb-ot-shape-private.hh
+++ b/src/hb-ot-shape-private.hh
@@ -100,8 +100,9 @@ is_variation_selector (hb_codepoint_t unicode)
 }
 
 
-HB_INTERNAL void _hb_normalize (hb_ot_shape_context_t *c);
+HB_INTERNAL bool _hb_normalize (hb_ot_shape_context_t *c);
 
+#define intermittent_glyph() var2.u32
 
 HB_END_DECLS
 
diff --git a/src/hb-ot-shape.cc b/src/hb-ot-shape.cc
index 50f2986..939bf4f 100644
--- a/src/hb-ot-shape.cc
+++ b/src/hb-ot-shape.cc
@@ -365,7 +365,9 @@ hb_ot_shape_execute_internal (hb_ot_shape_context_t *c)
 
   hb_ensure_native_direction (c);
 
-  _hb_normalize (c);
+  if (_hb_normalize (c))
+    /* Buffer contents changed, reset unicode_props */
+    hb_set_unicode_props (c); /* BUFFER: Set general_category and combining_class in var1 */
 
   hb_ot_shape_setup_masks (c); /* BUFFER: Clobbers var2 */
 
-- 
2.7.4