Add prefer_decomposed() complex-shaper callback

This allows the Indic shaper to request decomposed characters.  This will
handle split matra for free.  Other shapers prefer precomposed
characters.

diff --git a/src/hb-ot-shape-complex-arabic.cc b/src/hb-ot-shape-complex-arabic.cc
index 53e7a9b..dc63db2 100644 (file)
--- a/src/hb-ot-shape-complex-arabic.cc
+++ b/src/hb-ot-shape-complex-arabic.cc
@@ -183,6 +183,12 @@ _hb_ot_shape_complex_collect_features_arabic (hb_ot_map_builder_t *map, const hb
   map->add_bool_feature (HB_TAG('c','s','w','h'));
 }
 
+bool
+_hb_ot_shape_complex_prefer_decomposed_arabic (void)
+{
+  return FALSE;
+}
+
 void
 _hb_ot_shape_complex_setup_masks_arabic (hb_ot_map_t *map, hb_buffer_t *buffer)
 {

diff --git a/src/hb-ot-shape-complex-indic.cc b/src/hb-ot-shape-complex-indic.cc
index 03ea10f..cf5a049 100644 (file)
--- a/src/hb-ot-shape-complex-indic.cc
+++ b/src/hb-ot-shape-complex-indic.cc
@@ -309,6 +309,13 @@ _hb_ot_shape_complex_collect_features_indic (hb_ot_map_builder_t *map, const hb_
 }
 
 
+bool
+_hb_ot_shape_complex_prefer_decomposed_indic (void)
+{
+  /* We want split matras decomposed by the common shaping logic. */
+  return TRUE;
+}
+
 static void
 found_syllable (hb_ot_map_t *map, hb_buffer_t *buffer,
                unsigned int start, unsigned int end)

diff --git a/src/hb-ot-shape-complex-misc.cc b/src/hb-ot-shape-complex-misc.cc
index 92dee49..b2de3ff 100644 (file)
--- a/src/hb-ot-shape-complex-misc.cc
+++ b/src/hb-ot-shape-complex-misc.cc
@@ -42,6 +42,12 @@ _hb_ot_shape_complex_collect_features_default (hb_ot_map_builder_t *map, const h
 {
 }
 
+bool
+_hb_ot_shape_complex_prefer_decomposed_default (void)
+{
+  return FALSE;
+}
+
 void
 _hb_ot_shape_complex_setup_masks_default (hb_ot_map_t *map, hb_buffer_t *buffer)
 {

diff --git a/src/hb-ot-shape-complex-private.hh b/src/hb-ot-shape-complex-private.hh
index c10fdf9..4bfd855 100644 (file)
--- a/src/hb-ot-shape-complex-private.hh
+++ b/src/hb-ot-shape-complex-private.hh
@@ -140,7 +140,34 @@ hb_ot_shape_complex_collect_features (hb_ot_complex_shaper_t shaper,
   switch (shaper) {
     default:
 #define HB_COMPLEX_SHAPER_IMPLEMENT(name) \
-    case hb_ot_complex_shaper_##name:  _hb_ot_shape_complex_collect_features_##name    (map, props);   return;
+    case hb_ot_complex_shaper_##name:  _hb_ot_shape_complex_collect_features_##name (map, props); return;
+    HB_COMPLEX_SHAPERS_IMPLEMENT_SHAPERS
+#undef HB_COMPLEX_SHAPER_IMPLEMENT
+  }
+}
+
+
+/*
+ * prefer_decomposed()
+ *
+ * Called during shape_execute().
+ *
+ * Shapers should return TRUE if it prefers decomposed (NFD) input rather than precomposed (NFC).
+ */
+
+typedef bool hb_ot_shape_complex_prefer_decomposed_func_t (void);
+#define HB_COMPLEX_SHAPER_IMPLEMENT(name) \
+  HB_INTERNAL hb_ot_shape_complex_prefer_decomposed_func_t _hb_ot_shape_complex_prefer_decomposed_##name;
+  HB_COMPLEX_SHAPERS_IMPLEMENT_SHAPERS
+#undef HB_COMPLEX_SHAPER_IMPLEMENT
+
+static inline bool
+hb_ot_shape_complex_prefer_decomposed (hb_ot_complex_shaper_t shaper)
+{
+  switch (shaper) {
+    default:
+#define HB_COMPLEX_SHAPER_IMPLEMENT(name) \
+    case hb_ot_complex_shaper_##name:  return _hb_ot_shape_complex_prefer_decomposed_##name ();
     HB_COMPLEX_SHAPERS_IMPLEMENT_SHAPERS
 #undef HB_COMPLEX_SHAPER_IMPLEMENT
   }
@@ -168,7 +195,7 @@ hb_ot_shape_complex_setup_masks (hb_ot_complex_shaper_t shaper,
   switch (shaper) {
     default:
 #define HB_COMPLEX_SHAPER_IMPLEMENT(name) \
-    case hb_ot_complex_shaper_##name:  _hb_ot_shape_complex_setup_masks_##name (map, buffer);  return;
+    case hb_ot_complex_shaper_##name:  _hb_ot_shape_complex_setup_masks_##name (map, buffer); return;
     HB_COMPLEX_SHAPERS_IMPLEMENT_SHAPERS
 #undef HB_COMPLEX_SHAPER_IMPLEMENT
   }