[Complex Text Layouts] Add third-party TextServer dependencies (ICU, HarfBuzz, Graphite).

1 files changed, 442 insertions, 0 deletions

diff --git a/thirdparty/harfbuzz/src/hb-graphite2.cc b/thirdparty/harfbuzz/src/hb-graphite2.cc
new file mode 100644
index 0000000000..d8a72dc2f1
--- /dev/null
+++ b/thirdparty/harfbuzz/src/hb-graphite2.cc
@@ -0,0 +1,442 @@
+/*
+ * Copyright © 2011  Martin Hosken
+ * Copyright © 2011  SIL International
+ * Copyright © 2011,2012  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.hh"
+
+#ifdef HAVE_GRAPHITE2
+
+#include "hb-shaper-impl.hh"
+
+#include "hb-graphite2.h"
+
+#include <graphite2/Segment.h>
+
+#include "hb-ot-layout.h"
+
+
+/**
+ * SECTION:hb-graphite2
+ * @title: hb-graphite2
+ * @short_description: Graphite2 integration
+ * @include: hb-graphite2.h
+ *
+ * Functions for using HarfBuzz with fonts that include Graphite features.
+ * 
+ * For Graphite features to work, you must be sure that HarfBuzz was compiled
+ * with the `graphite2` shaping engine enabled. Currently, the default is to
+ * not enable `graphite2` shaping.
+ **/
+
+
+/*
+ * shaper face data
+ */
+
+typedef struct hb_graphite2_tablelist_t
+{
+  struct hb_graphite2_tablelist_t *next;
+  hb_blob_t *blob;
+  unsigned int tag;
+} hb_graphite2_tablelist_t;
+
+struct hb_graphite2_face_data_t
+{
+  hb_face_t *face;
+  gr_face   *grface;
+  hb_atomic_ptr_t<hb_graphite2_tablelist_t> tlist;
+};
+
+static const void *hb_graphite2_get_table (const void *data, unsigned int tag, size_t *len)
+{
+  hb_graphite2_face_data_t *face_data = (hb_graphite2_face_data_t *) data;
+  hb_graphite2_tablelist_t *tlist = face_data->tlist;
+
+  hb_blob_t *blob = nullptr;
+
+  for (hb_graphite2_tablelist_t *p = tlist; p; p = p->next)
+    if (p->tag == tag) {
+      blob = p->blob;
+      break;
+    }
+
+  if (unlikely (!blob))
+  {
+    blob = face_data->face->reference_table (tag);
+
+    hb_graphite2_tablelist_t *p = (hb_graphite2_tablelist_t *) calloc (1, sizeof (hb_graphite2_tablelist_t));
+    if (unlikely (!p)) {
+      hb_blob_destroy (blob);
+      return nullptr;
+    }
+    p->blob = blob;
+    p->tag = tag;
+
+retry:
+    hb_graphite2_tablelist_t *tlist = face_data->tlist;
+    p->next = tlist;
+
+    if (unlikely (!face_data->tlist.cmpexch (tlist, p)))
+      goto retry;
+  }
+
+  unsigned int tlen;
+  const char *d = hb_blob_get_data (blob, &tlen);
+  *len = tlen;
+  return d;
+}
+
+hb_graphite2_face_data_t *
+_hb_graphite2_shaper_face_data_create (hb_face_t *face)
+{
+  hb_blob_t *silf_blob = face->reference_table (HB_GRAPHITE2_TAG_SILF);
+  /* Umm, we just reference the table to check whether it exists.
+   * Maybe add better API for this? */
+  if (!hb_blob_get_length (silf_blob))
+  {
+    hb_blob_destroy (silf_blob);
+    return nullptr;
+  }
+  hb_blob_destroy (silf_blob);
+
+  hb_graphite2_face_data_t *data = (hb_graphite2_face_data_t *) calloc (1, sizeof (hb_graphite2_face_data_t));
+  if (unlikely (!data))
+    return nullptr;
+
+  data->face = face;
+  data->grface = gr_make_face (data, &hb_graphite2_get_table, gr_face_preloadAll);
+
+  if (unlikely (!data->grface)) {
+    free (data);
+    return nullptr;
+  }
+
+  return data;
+}
+
+void
+_hb_graphite2_shaper_face_data_destroy (hb_graphite2_face_data_t *data)
+{
+  hb_graphite2_tablelist_t *tlist = data->tlist;
+
+  while (tlist)
+  {
+    hb_graphite2_tablelist_t *old = tlist;
+    hb_blob_destroy (tlist->blob);
+    tlist = tlist->next;
+    free (old);
+  }
+
+  gr_face_destroy (data->grface);
+
+  free (data);
+}
+
+/**
+ * hb_graphite2_face_get_gr_face:
+ * @face: @hb_face_t to query
+ *
+ * Fetches the Graphite2 gr_face corresponding to the specified
+ * #hb_face_t face object.
+ *
+ * Return value: the gr_face found
+ *
+ * Since: 0.9.10
+ */
+gr_face *
+hb_graphite2_face_get_gr_face (hb_face_t *face)
+{
+  const hb_graphite2_face_data_t *data = face->data.graphite2;
+  return data ? data->grface : nullptr;
+}
+
+
+/*
+ * shaper font data
+ */
+
+struct hb_graphite2_font_data_t {};
+
+hb_graphite2_font_data_t *
+_hb_graphite2_shaper_font_data_create (hb_font_t *font HB_UNUSED)
+{
+  return (hb_graphite2_font_data_t *) HB_SHAPER_DATA_SUCCEEDED;
+}
+
+void
+_hb_graphite2_shaper_font_data_destroy (hb_graphite2_font_data_t *data HB_UNUSED)
+{
+}
+
+#ifndef HB_DISABLE_DEPRECATED
+/**
+ * hb_graphite2_font_get_gr_font:
+ *
+ * Since: 0.9.10
+ * Deprecated: 1.4.2
+ */
+gr_font *
+hb_graphite2_font_get_gr_font (hb_font_t *font HB_UNUSED)
+{
+  return nullptr;
+}
+#endif
+
+
+/*
+ * shaper
+ */
+
+struct hb_graphite2_cluster_t {
+  unsigned int base_char;
+  unsigned int num_chars;
+  unsigned int base_glyph;
+  unsigned int num_glyphs;
+  unsigned int cluster;
+  unsigned int advance;
+};
+
+hb_bool_t
+_hb_graphite2_shape (hb_shape_plan_t    *shape_plan HB_UNUSED,
+		     hb_font_t          *font,
+		     hb_buffer_t        *buffer,
+		     const hb_feature_t *features,
+		     unsigned int        num_features)
+{
+  hb_face_t *face = font->face;
+  gr_face *grface = face->data.graphite2->grface;
+
+  const char *lang = hb_language_to_string (hb_buffer_get_language (buffer));
+  const char *lang_end = lang ? strchr (lang, '-') : nullptr;
+  int lang_len = lang_end ? lang_end - lang : -1;
+  gr_feature_val *feats = gr_face_featureval_for_lang (grface, lang ? hb_tag_from_string (lang, lang_len) : 0);
+
+  for (unsigned int i = 0; i < num_features; i++)
+  {
+    const gr_feature_ref *fref = gr_face_find_fref (grface, features[i].tag);
+    if (fref)
+      gr_fref_set_feature_value (fref, features[i].value, feats);
+  }
+
+  gr_segment *seg = nullptr;
+  const gr_slot *is;
+  unsigned int ci = 0, ic = 0;
+  unsigned int curradvx = 0, curradvy = 0;
+
+  unsigned int scratch_size;
+  hb_buffer_t::scratch_buffer_t *scratch = buffer->get_scratch_buffer (&scratch_size);
+
+  uint32_t *chars = (uint32_t *) scratch;
+
+  for (unsigned int i = 0; i < buffer->len; ++i)
+    chars[i] = buffer->info[i].codepoint;
+
+  /* TODO ensure_native_direction. */
+
+  hb_tag_t script_tag[HB_OT_MAX_TAGS_PER_SCRIPT];
+  unsigned int count = HB_OT_MAX_TAGS_PER_SCRIPT;
+  hb_ot_tags_from_script_and_language (hb_buffer_get_script (buffer),
+				       HB_LANGUAGE_INVALID,
+				       &count,
+				       script_tag,
+				       nullptr, nullptr);
+
+  seg = gr_make_seg (nullptr, grface,
+		     count ? script_tag[count - 1] : HB_OT_TAG_DEFAULT_SCRIPT,
+		     feats,
+		     gr_utf32, chars, buffer->len,
+		     2 | (hb_buffer_get_direction (buffer) == HB_DIRECTION_RTL ? 1 : 0));
+
+  if (unlikely (!seg)) {
+    if (feats) gr_featureval_destroy (feats);
+    return false;
+  }
+
+  unsigned int glyph_count = gr_seg_n_slots (seg);
+  if (unlikely (!glyph_count)) {
+    if (feats) gr_featureval_destroy (feats);
+    gr_seg_destroy (seg);
+    buffer->len = 0;
+    return true;
+  }
+
+  buffer->ensure (glyph_count);
+  scratch = buffer->get_scratch_buffer (&scratch_size);
+  while ((DIV_CEIL (sizeof (hb_graphite2_cluster_t) * buffer->len, sizeof (*scratch)) +
+	  DIV_CEIL (sizeof (hb_codepoint_t) * glyph_count, sizeof (*scratch))) > scratch_size)
+  {
+    if (unlikely (!buffer->ensure (buffer->allocated * 2)))
+    {
+      if (feats) gr_featureval_destroy (feats);
+      gr_seg_destroy (seg);
+      return false;
+    }
+    scratch = buffer->get_scratch_buffer (&scratch_size);
+  }
+
+#define ALLOCATE_ARRAY(Type, name, len) \
+  Type *name = (Type *) scratch; \
+  do { \
+    unsigned int _consumed = DIV_CEIL ((len) * sizeof (Type), sizeof (*scratch)); \
+    assert (_consumed <= scratch_size); \
+    scratch += _consumed; \
+    scratch_size -= _consumed; \
+  } while (0)
+
+  ALLOCATE_ARRAY (hb_graphite2_cluster_t, clusters, buffer->len);
+  ALLOCATE_ARRAY (hb_codepoint_t, gids, glyph_count);
+
+#undef ALLOCATE_ARRAY
+
+  memset (clusters, 0, sizeof (clusters[0]) * buffer->len);
+
+  hb_codepoint_t *pg = gids;
+  clusters[0].cluster = buffer->info[0].cluster;
+  unsigned int upem = hb_face_get_upem (face);
+  float xscale = (float) font->x_scale / upem;
+  float yscale = (float) font->y_scale / upem;
+  yscale *= yscale / xscale;
+  unsigned int curradv = 0;
+  if (HB_DIRECTION_IS_BACKWARD(buffer->props.direction))
+  {
+    curradv = gr_slot_origin_X(gr_seg_first_slot(seg)) * xscale;
+    clusters[0].advance = gr_seg_advance_X(seg) * xscale - curradv;
+  }
+  else
+    clusters[0].advance = 0;
+  for (is = gr_seg_first_slot (seg), ic = 0; is; is = gr_slot_next_in_segment (is), ic++)
+  {
+    unsigned int before = gr_slot_before (is);
+    unsigned int after = gr_slot_after (is);
+    *pg = gr_slot_gid (is);
+    pg++;
+    while (clusters[ci].base_char > before && ci)
+    {
+      clusters[ci-1].num_chars += clusters[ci].num_chars;
+      clusters[ci-1].num_glyphs += clusters[ci].num_glyphs;
+      clusters[ci-1].advance += clusters[ci].advance;
+      ci--;
+    }
+
+    if (gr_slot_can_insert_before (is) && clusters[ci].num_chars && before >= clusters[ci].base_char + clusters[ci].num_chars)
+    {
+      hb_graphite2_cluster_t *c = clusters + ci + 1;
+      c->base_char = clusters[ci].base_char + clusters[ci].num_chars;
+      c->cluster = buffer->info[c->base_char].cluster;
+      c->num_chars = before - c->base_char;
+      c->base_glyph = ic;
+      c->num_glyphs = 0;
+      if (HB_DIRECTION_IS_BACKWARD(buffer->props.direction))
+      {
+	c->advance = curradv - gr_slot_origin_X(is) * xscale;
+	curradv -= c->advance;
+      }
+      else
+      {
+	c->advance = 0;
+	clusters[ci].advance += gr_slot_origin_X(is) * xscale - curradv;
+	curradv += clusters[ci].advance;
+      }
+      ci++;
+    }
+    clusters[ci].num_glyphs++;
+
+    if (clusters[ci].base_char + clusters[ci].num_chars < after + 1)
+	clusters[ci].num_chars = after + 1 - clusters[ci].base_char;
+  }
+
+  if (HB_DIRECTION_IS_BACKWARD(buffer->props.direction))
+    clusters[ci].advance += curradv;
+  else
+    clusters[ci].advance += gr_seg_advance_X(seg) * xscale - curradv;
+  ci++;
+
+  for (unsigned int i = 0; i < ci; ++i)
+  {
+    for (unsigned int j = 0; j < clusters[i].num_glyphs; ++j)
+    {
+      hb_glyph_info_t *info = &buffer->info[clusters[i].base_glyph + j];
+      info->codepoint = gids[clusters[i].base_glyph + j];
+      info->cluster = clusters[i].cluster;
+      info->var1.i32 = clusters[i].advance;     // all glyphs in the cluster get the same advance
+    }
+  }
+  buffer->len = glyph_count;
+
+  /* Positioning. */
+  unsigned int currclus = UINT_MAX;
+  const hb_glyph_info_t *info = buffer->info;
+  hb_glyph_position_t *pPos = hb_buffer_get_glyph_positions (buffer, nullptr);
+  if (!HB_DIRECTION_IS_BACKWARD(buffer->props.direction))
+  {
+    curradvx = 0;
+    for (is = gr_seg_first_slot (seg); is; pPos++, ++info, is = gr_slot_next_in_segment (is))
+    {
+      pPos->x_offset = gr_slot_origin_X (is) * xscale - curradvx;
+      pPos->y_offset = gr_slot_origin_Y (is) * yscale - curradvy;
+      if (info->cluster != currclus) {
+	pPos->x_advance = info->var1.i32;
+	curradvx += pPos->x_advance;
+	currclus = info->cluster;
+      } else
+	pPos->x_advance = 0.;
+
+      pPos->y_advance = gr_slot_advance_Y (is, grface, nullptr) * yscale;
+      curradvy += pPos->y_advance;
+    }
+  }
+  else
+  {
+    curradvx = gr_seg_advance_X(seg) * xscale;
+    for (is = gr_seg_first_slot (seg); is; pPos++, info++, is = gr_slot_next_in_segment (is))
+    {
+      if (info->cluster != currclus)
+      {
+	pPos->x_advance = info->var1.i32;
+	curradvx -= pPos->x_advance;
+	currclus = info->cluster;
+      } else
+	pPos->x_advance = 0.;
+
+      pPos->y_advance = gr_slot_advance_Y (is, grface, nullptr) * yscale;
+      curradvy -= pPos->y_advance;
+      pPos->x_offset = gr_slot_origin_X (is) * xscale - info->var1.i32 - curradvx + pPos->x_advance;
+      pPos->y_offset = gr_slot_origin_Y (is) * yscale - curradvy;
+    }
+    hb_buffer_reverse_clusters (buffer);
+  }
+
+  if (feats) gr_featureval_destroy (feats);
+  gr_seg_destroy (seg);
+
+  buffer->unsafe_to_break_all ();
+
+  return true;
+}
+
+
+#endif