[BASE] Improvements (#1347)

src/hb-ot-layout.cc

@@ -37,10 +37,8 @@
 #include "hb-ot-layout-gdef-table.hh"
 #include "hb-ot-layout-gsub-table.hh"
 #include "hb-ot-layout-gpos-table.hh"
-
-#include "hb-ot-layout-base-table.hh" // Just so we compile them; unused otherwise
-#include "hb-ot-layout-jstf-table.hh" // Just so we compile them; unused otherwise
-
+#include "hb-ot-layout-base-table.hh" // Just so we compile it; unused otherwise
+#include "hb-ot-layout-jstf-table.hh" // Just so we compile it; unused otherwise
 #include "hb-ot-kern-table.hh"
 #include "hb-ot-name-table.hh"
 
@@ -1425,3 +1423,62 @@ hb_ot_layout_substitute_lookup (OT::hb_ot_apply_context_t *c,
 {
   apply_string<GSUBProxy> (c, lookup, accel);
 }
+
+#if 0
+static const OT::BASE& _get_base (hb_face_t *face)
+{
+  if (unlikely (!hb_ot_shaper_face_data_ensure (face))) return Null(OT::BASE);
+  return *hb_ot_face_data (face)->BASE;
+}
+
+hb_bool_t
+hb_ot_layout_get_baseline (hb_font_t               *font,
+			   hb_ot_layout_baseline_t  baseline,
+			   hb_direction_t           direction,
+			   hb_tag_t                 script_tag,
+			   hb_tag_t                 language_tag,
+			   hb_position_t           *coord        /* OUT.  May be NULL. */)
+{
+  const OT::BASE &base = _get_base (font->face);
+  bool result = base.get_baseline (font, baseline, direction, script_tag,
+				   language_tag, coord);
+
+  /* TODO: Simulate https://docs.microsoft.com/en-us/typography/opentype/spec/baselinetags#ideographic-em-box */
+  if (!result && coord) *coord = 0;
+
+  if (coord) *coord = font->em_scale_dir (*coord, direction);
+
+  return result;
+}
+
+/* To be moved to public header */
+/*
+ * BASE
+ */
+
+/**
+ * hb_ot_layout_baseline_t:
+ *
+ * https://docs.microsoft.com/en-us/typography/opentype/spec/baselinetags
+ *
+ * Since: DONTREPLACEME
+ */
+typedef enum {
+  HB_OT_LAYOUT_BASELINE_HANG = HB_TAG('h','a','n','g'),
+  HB_OT_LAYOUT_BASELINE_ICFB = HB_TAG('i','c','f','b'),
+  HB_OT_LAYOUT_BASELINE_ICFT = HB_TAG('i','c','f','t'),
+  HB_OT_LAYOUT_BASELINE_IDEO = HB_TAG('i','d','e','o'),
+  HB_OT_LAYOUT_BASELINE_IDTB = HB_TAG('i','d','t','b'),
+  HB_OT_LAYOUT_BASELINE_MATH = HB_TAG('m','a','t','h'),
+  HB_OT_LAYOUT_BASELINE_ROMN = HB_TAG('r','o','m','n')
+} hb_ot_layout_baseline_t;
+
+HB_EXTERN hb_bool_t
+hb_ot_layout_get_baseline (hb_font_t               *font,
+			   hb_ot_layout_baseline_t  baseline,
+			   hb_direction_t           direction,
+			   hb_tag_t                 script_tag,
+			   hb_tag_t                 language_tag,
+			   hb_position_t           *coord        /* OUT.  May be NULL. */);
+
+#endif

src/hb-ot-layout.h

@@ -391,22 +391,6 @@ hb_ot_layout_feature_get_characters (hb_face_t      *face,
 				     unsigned int   *char_count    /* IN/OUT.  May be NULL */,
 				     hb_codepoint_t *characters    /* OUT.     May be NULL */);
 
-/*
- * BASE
- */
-#if 0
-
-#define HB_OT_TAG_BASE_HANG HB_TAG('h','a','n','g')
-#define HB_OT_TAG_BASE_ICFB HB_TAG('i','c','f','b')
-#define HB_OT_TAG_BASE_ICFT HB_TAG('i','c','f','t')
-#define HB_OT_TAG_BASE_IDEO HB_TAG('i','d','e','o')
-#define HB_OT_TAG_BASE_IDTB HB_TAG('i','d','t','b')
-#define HB_OT_TAG_BASE_MATH HB_TAG('m','a','t','h')
-#define HB_OT_TAG_BASE_ROMN HB_TAG('r','o','m','n')
-
-#endif
-
-
 HB_END_DECLS
 
 #endif /* HB_OT_LAYOUT_H */

test/api/Makefile.am

@@ -28,6 +28,7 @@ check_PROGRAMS = $(TEST_PROGS)
 noinst_PROGRAMS = $(TEST_PROGS)
 
 TEST_PROGS = \
+	test-baseline \
 	test-blob \
 	test-buffer \
 	test-collect-unicodes \

test/api/test-baseline.c

+/*
+ * 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>
+
+/* Unit tests for hb-ot-layout.h baseline */
+
+static void
+test_ot_layout_base (void)
+{
+  hb_face_t *face = hb_test_open_font_file ("fonts/base.ttf");
+  hb_font_t *font = hb_font_create (face);
+
+#if 0
+  hb_position_t position;
+  g_assert (hb_ot_layout_get_baseline (font, HB_OT_LAYOUT_BASELINE_ICFB, HB_DIRECTION_TTB,
+				       HB_TAG ('h','a','n','i'),
+				       HB_TAG ('E','N','G',' '),
+				       &position));
+  g_assert_cmpint (46, ==, position);
+#endif
+
+  hb_font_destroy (font);
+  hb_face_destroy (face);
+}
+
+int
+main (int argc, char **argv)
+{
+  hb_test_init (&argc, &argv);
+
+  hb_test_add (test_ot_layout_base);
+
+  return hb_test_run();
+}