Hook AAT's lcar to _get_ligature_carets

src/Makefile.sources

@@ -102,6 +102,7 @@ HB_OT_sources = \
 	hb-aat-layout-feat-table.hh \
 	hb-aat-layout-just-table.hh \
 	hb-aat-layout-kerx-table.hh \
+	hb-aat-layout-lcar-table.hh \
 	hb-aat-layout-morx-table.hh \
 	hb-aat-layout-trak-table.hh \
 	hb-aat-layout.hh \

src/hb-aat-layout-lcar-table.hh

@@ -0,0 +1,92 @@
+/*
+ * Copyright © 2018  Ebrahim Byagowi
+ *
+ *  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.
+ */
+#ifndef HB_AAT_LAYOUT_LCAR_TABLE_HH
+#define HB_AAT_LAYOUT_LCAR_TABLE_HH
+
+#include "hb-open-type.hh"
+#include "hb-aat-layout-common.hh"
+
+/*
+ * lcar -- Ligature caret
+ * https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6lcar.html
+ */
+#define HB_AAT_TAG_lcar HB_TAG('l','c','a','r')
+
+
+namespace AAT {
+
+typedef ArrayOf<HBINT16> LigCaretClassEntry;
+
+struct lcar
+{
+  static const hb_tag_t tableTag = HB_AAT_TAG_lcar;
+
+  inline unsigned int get_lig_carets (hb_font_t      *font,
+				      hb_direction_t  direction,
+				      hb_codepoint_t  glyph,
+				      unsigned int    start_offset,
+				      unsigned int   *caret_count /* IN/OUT */,
+				      hb_position_t  *caret_array /* OUT */) const
+  {
+    const OffsetTo<LigCaretClassEntry>* entry_offset = lookup.get_value (glyph, font->face->num_glyphs);
+    const LigCaretClassEntry& array = entry_offset ? this+*entry_offset : Null (LigCaretClassEntry);
+    if (caret_count && *caret_count)
+    {
+      const HBINT16 *arr = array.sub_array (start_offset, caret_count);
+      unsigned int count = *caret_count;
+      for (unsigned int i = 0; i < count; ++i)
+	switch (format)
+	{
+	case 0: caret_array[i] = font->em_scale_dir (arr[i], direction); break;
+	case 1:
+	  hb_position_t x, y;
+	  font->get_glyph_contour_point_for_origin (glyph, arr[i], direction, &x, &y);
+	  caret_array[i] = HB_DIRECTION_IS_HORIZONTAL (direction) ? x : y;
+	  break;
+	}
+    }
+    return array.len;
+  }
+
+  inline bool sanitize (hb_sanitize_context_t *c) const
+  {
+    TRACE_SANITIZE (this);
+    return_trace (likely (c->check_struct (this) &&
+			  version.major == 1 &&
+			  lookup.sanitize (c, this)));
+  }
+
+  protected:
+  FixedVersion<>version;	/* Version number of the ligature caret table */
+  HBUINT16	format;		/* Format of the ligature caret table. */
+  Lookup<OffsetTo<LigCaretClassEntry> >
+		lookup;		/* data Lookup table associating glyphs */
+
+  public:
+  DEFINE_SIZE_MIN (8);
+};
+
+} /* namespace AAT */
+
+#endif /* HB_AAT_LAYOUT_LCAR_TABLE_HH */

src/hb-ot-face.hh

@@ -60,6 +60,7 @@
     HB_OT_TABLE(AAT, kerx) \
     HB_OT_TABLE(AAT, ankr) \
     HB_OT_TABLE(AAT, trak) \
+    HB_OT_TABLE(AAT, lcar) \
     HB_OT_TABLE(AAT, ltag) \
     /* OpenType variations. */ \
     HB_OT_TABLE(OT, fvar) \

src/hb-ot-layout-gdef-table.hh

@@ -123,10 +123,8 @@ struct CaretValueFormat2
   inline hb_position_t get_caret_value (hb_font_t *font, hb_direction_t direction, hb_codepoint_t glyph_id) const
   {
     hb_position_t x, y;
-    if (font->get_glyph_contour_point_for_origin (glyph_id, caretValuePoint, direction, &x, &y))
+    font->get_glyph_contour_point_for_origin (glyph_id, caretValuePoint, direction, &x, &y);
     return HB_DIRECTION_IS_HORIZONTAL (direction) ? x : y;
-    else
-      return 0;
   }
 
   inline bool sanitize (hb_sanitize_context_t *c) const

src/hb-ot-layout.cc

@@ -42,6 +42,8 @@
 #include "hb-ot-kern-table.hh"
 #include "hb-ot-name-table.hh"
 
+#include "hb-aat-layout-lcar-table.hh"
+
 
 /**
  * SECTION:hb-ot-layout
@@ -275,12 +277,15 @@ hb_ot_layout_get_ligature_carets (hb_font_t      *font,
 				  unsigned int   *caret_count /* IN/OUT */,
 				  hb_position_t  *caret_array /* OUT */)
 {
-  return font->face->table.GDEF->table->get_lig_carets (font,
+  unsigned int result_caret_count = 0;
-							direction,
+  unsigned int result = font->face->table.GDEF->table->get_lig_carets (font, direction, glyph, start_offset, &result_caret_count, caret_array);
-							glyph,
+  if (result)
-							start_offset,
+  {
-							caret_count,
+    if (caret_count) *caret_count = result_caret_count;
-							caret_array);
+  }
+  else
+    result = font->face->table.lcar->get_lig_carets (font, direction, glyph, start_offset, caret_count, caret_array);
+  return result;
 }
 
 

test/api/Makefile.am

@@ -74,6 +74,7 @@ endif
 
 TEST_PROGS += \
 	test-ot-color \
+	test-ot-ligature-carets \
 	test-ot-name \
 	test-ot-tag \
 	$(NULL)

test/api/test-ot-ligature-carets.c

@@ -0,0 +1,67 @@
+/*
+ * Copyright © 2018  Ebrahim Byagowi
+ *
+ *  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.
+ *
+ */
+
+#include "hb-test.h"
+
+#include <hb-ot.h>
+
+static void
+test_ot_layout_feature_get_name_ids_and_characters (void)
+{
+  hb_face_t *face = hb_test_open_font_file ("fonts/lcar.ttf");
+  hb_font_t *font = hb_font_create (face);
+  hb_font_set_scale (font, hb_face_get_upem (face) * 2, hb_face_get_upem (face) * 4);
+
+  hb_position_t caret_array[2];
+  unsigned int caret_count = 2;
+  g_assert_cmpuint (2, ==, hb_ot_layout_get_ligature_carets (font, HB_DIRECTION_RTL,
+							     98, 0, &caret_count,
+							     caret_array));
+
+  g_assert_cmpuint (2, ==, caret_count);
+  g_assert_cmpuint (1130, ==, caret_array[0]);
+  g_assert_cmpuint (2344, ==, caret_array[1]);
+
+  g_assert_cmpuint (2, ==, hb_ot_layout_get_ligature_carets (font, HB_DIRECTION_BTT,
+							     98, 0, &caret_count,
+							     caret_array));
+
+  g_assert_cmpuint (2, ==, caret_count);
+  g_assert_cmpuint (2260, ==, caret_array[0]);
+  g_assert_cmpuint (4688, ==, caret_array[1]);
+
+  hb_font_destroy (font);
+  hb_face_destroy (face);
+}
+
+int
+main (int argc, char **argv)
+{
+  g_test_init (&argc, &argv, NULL);
+
+  hb_test_add (test_ot_layout_feature_get_name_ids_and_characters);
+
+  return hb_test_run ();
+}