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authorMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
committerMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
commit5f8de423f190bbb79a62f804151bc24824fa32d8 (patch)
tree10027f336435511475e392454359edea8e25895d /gfx/harfbuzz/src/hb-ot-font.cc
parent49ee0794b5d912db1f95dce6eb52d781dc210db5 (diff)
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Add m-esr52 at 52.6.0
Diffstat (limited to 'gfx/harfbuzz/src/hb-ot-font.cc')
-rw-r--r--gfx/harfbuzz/src/hb-ot-font.cc662
1 files changed, 662 insertions, 0 deletions
diff --git a/gfx/harfbuzz/src/hb-ot-font.cc b/gfx/harfbuzz/src/hb-ot-font.cc
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+++ b/gfx/harfbuzz/src/hb-ot-font.cc
@@ -0,0 +1,662 @@
+/*
+ * Copyright © 2011,2014 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, Roozbeh Pournader
+ */
+
+#include "hb-private.hh"
+
+#include "hb-ot.h"
+
+#include "hb-font-private.hh"
+
+#include "hb-ot-cmap-table.hh"
+#include "hb-ot-cbdt-table.hh"
+#include "hb-ot-glyf-table.hh"
+#include "hb-ot-head-table.hh"
+#include "hb-ot-hhea-table.hh"
+#include "hb-ot-hmtx-table.hh"
+#include "hb-ot-os2-table.hh"
+//#include "hb-ot-post-table.hh"
+
+
+struct hb_ot_face_metrics_accelerator_t
+{
+ unsigned int num_metrics;
+ unsigned int num_advances;
+ unsigned int default_advance;
+ unsigned short ascender;
+ unsigned short descender;
+ unsigned short line_gap;
+ bool has_font_extents;
+
+ const OT::_mtx *table;
+ hb_blob_t *blob;
+
+ inline void init (hb_face_t *face,
+ hb_tag_t _hea_tag,
+ hb_tag_t _mtx_tag,
+ hb_tag_t os2_tag,
+ unsigned int default_advance = 0)
+ {
+ this->default_advance = default_advance ? default_advance : face->get_upem ();
+
+ bool got_font_extents = false;
+ if (os2_tag)
+ {
+ hb_blob_t *os2_blob = OT::Sanitizer<OT::os2>::sanitize (face->reference_table (os2_tag));
+ const OT::os2 *os2 = OT::Sanitizer<OT::os2>::lock_instance (os2_blob);
+#define USE_TYPO_METRICS (1u<<7)
+ if (0 != (os2->fsSelection & USE_TYPO_METRICS))
+ {
+ this->ascender = os2->sTypoAscender;
+ this->descender = os2->sTypoDescender;
+ this->line_gap = os2->sTypoLineGap;
+ got_font_extents = (this->ascender | this->descender) != 0;
+ }
+ hb_blob_destroy (os2_blob);
+ }
+
+ hb_blob_t *_hea_blob = OT::Sanitizer<OT::_hea>::sanitize (face->reference_table (_hea_tag));
+ const OT::_hea *_hea = OT::Sanitizer<OT::_hea>::lock_instance (_hea_blob);
+ this->num_advances = _hea->numberOfLongMetrics;
+ if (!got_font_extents)
+ {
+ this->ascender = _hea->ascender;
+ this->descender = _hea->descender;
+ this->line_gap = _hea->lineGap;
+ got_font_extents = (this->ascender | this->descender) != 0;
+ }
+ hb_blob_destroy (_hea_blob);
+
+ this->has_font_extents = got_font_extents;
+
+ this->blob = OT::Sanitizer<OT::_mtx>::sanitize (face->reference_table (_mtx_tag));
+
+ /* Cap num_metrics() and num_advances() based on table length. */
+ unsigned int len = hb_blob_get_length (this->blob);
+ if (unlikely (this->num_advances * 4 > len))
+ this->num_advances = len / 4;
+ this->num_metrics = this->num_advances + (len - 4 * this->num_advances) / 2;
+
+ /* We MUST set num_metrics to zero if num_advances is zero.
+ * Our get_advance() depends on that. */
+ if (unlikely (!this->num_advances))
+ {
+ this->num_metrics = this->num_advances = 0;
+ hb_blob_destroy (this->blob);
+ this->blob = hb_blob_get_empty ();
+ }
+ this->table = OT::Sanitizer<OT::_mtx>::lock_instance (this->blob);
+ }
+
+ inline void fini (void)
+ {
+ hb_blob_destroy (this->blob);
+ }
+
+ inline unsigned int get_advance (hb_codepoint_t glyph) const
+ {
+ if (unlikely (glyph >= this->num_metrics))
+ {
+ /* If this->num_metrics is zero, it means we don't have the metrics table
+ * for this direction: return default advance. Otherwise, it means that the
+ * glyph index is out of bound: return zero. */
+ if (this->num_metrics)
+ return 0;
+ else
+ return this->default_advance;
+ }
+
+ if (glyph >= this->num_advances)
+ glyph = this->num_advances - 1;
+
+ return this->table->longMetric[glyph].advance;
+ }
+};
+
+struct hb_ot_face_glyf_accelerator_t
+{
+ bool short_offset;
+ unsigned int num_glyphs;
+ const OT::loca *loca;
+ const OT::glyf *glyf;
+ hb_blob_t *loca_blob;
+ hb_blob_t *glyf_blob;
+ unsigned int glyf_len;
+
+ inline void init (hb_face_t *face)
+ {
+ hb_blob_t *head_blob = OT::Sanitizer<OT::head>::sanitize (face->reference_table (HB_OT_TAG_head));
+ const OT::head *head = OT::Sanitizer<OT::head>::lock_instance (head_blob);
+ if ((unsigned int) head->indexToLocFormat > 1 || head->glyphDataFormat != 0)
+ {
+ /* Unknown format. Leave num_glyphs=0, that takes care of disabling us. */
+ hb_blob_destroy (head_blob);
+ return;
+ }
+ this->short_offset = 0 == head->indexToLocFormat;
+ hb_blob_destroy (head_blob);
+
+ this->loca_blob = OT::Sanitizer<OT::loca>::sanitize (face->reference_table (HB_OT_TAG_loca));
+ this->loca = OT::Sanitizer<OT::loca>::lock_instance (this->loca_blob);
+ this->glyf_blob = OT::Sanitizer<OT::glyf>::sanitize (face->reference_table (HB_OT_TAG_glyf));
+ this->glyf = OT::Sanitizer<OT::glyf>::lock_instance (this->glyf_blob);
+
+ this->num_glyphs = MAX (1u, hb_blob_get_length (this->loca_blob) / (this->short_offset ? 2 : 4)) - 1;
+ this->glyf_len = hb_blob_get_length (this->glyf_blob);
+ }
+
+ inline void fini (void)
+ {
+ hb_blob_destroy (this->loca_blob);
+ hb_blob_destroy (this->glyf_blob);
+ }
+
+ inline bool get_extents (hb_codepoint_t glyph,
+ hb_glyph_extents_t *extents) const
+ {
+ if (unlikely (glyph >= this->num_glyphs))
+ return false;
+
+ unsigned int start_offset, end_offset;
+ if (this->short_offset)
+ {
+ start_offset = 2 * this->loca->u.shortsZ[glyph];
+ end_offset = 2 * this->loca->u.shortsZ[glyph + 1];
+ }
+ else
+ {
+ start_offset = this->loca->u.longsZ[glyph];
+ end_offset = this->loca->u.longsZ[glyph + 1];
+ }
+
+ if (start_offset > end_offset || end_offset > this->glyf_len)
+ return false;
+
+ if (end_offset - start_offset < OT::glyfGlyphHeader::static_size)
+ return true; /* Empty glyph; zero extents. */
+
+ const OT::glyfGlyphHeader &glyph_header = OT::StructAtOffset<OT::glyfGlyphHeader> (this->glyf, start_offset);
+
+ extents->x_bearing = MIN (glyph_header.xMin, glyph_header.xMax);
+ extents->y_bearing = MAX (glyph_header.yMin, glyph_header.yMax);
+ extents->width = MAX (glyph_header.xMin, glyph_header.xMax) - extents->x_bearing;
+ extents->height = MIN (glyph_header.yMin, glyph_header.yMax) - extents->y_bearing;
+
+ return true;
+ }
+};
+
+struct hb_ot_face_cbdt_accelerator_t
+{
+ hb_blob_t *cblc_blob;
+ hb_blob_t *cbdt_blob;
+ const OT::CBLC *cblc;
+ const OT::CBDT *cbdt;
+
+ unsigned int cbdt_len;
+ float upem;
+
+ inline void init (hb_face_t *face)
+ {
+ upem = face->get_upem();
+
+ cblc_blob = OT::Sanitizer<OT::CBLC>::sanitize (face->reference_table (HB_OT_TAG_CBLC));
+ cbdt_blob = OT::Sanitizer<OT::CBDT>::sanitize (face->reference_table (HB_OT_TAG_CBDT));
+ cbdt_len = hb_blob_get_length (cbdt_blob);
+
+ if (hb_blob_get_length (cblc_blob) == 0) {
+ cblc = NULL;
+ cbdt = NULL;
+ return; /* Not a bitmap font. */
+ }
+ cblc = OT::Sanitizer<OT::CBLC>::lock_instance (cblc_blob);
+ cbdt = OT::Sanitizer<OT::CBDT>::lock_instance (cbdt_blob);
+
+ }
+
+ inline void fini (void)
+ {
+ hb_blob_destroy (this->cblc_blob);
+ hb_blob_destroy (this->cbdt_blob);
+ }
+
+ inline bool get_extents (hb_codepoint_t glyph, hb_glyph_extents_t *extents) const
+ {
+ unsigned int x_ppem = upem, y_ppem = upem; /* TODO Use font ppem if available. */
+
+ if (cblc == NULL)
+ return false; // Not a color bitmap font.
+
+ const OT::IndexSubtableRecord *subtable_record = this->cblc->find_table(glyph, &x_ppem, &y_ppem);
+ if (subtable_record == NULL)
+ return false;
+
+ if (subtable_record->get_extents (extents))
+ return true;
+
+ unsigned int image_offset = 0, image_length = 0, image_format = 0;
+ if (!subtable_record->get_image_data (glyph, &image_offset, &image_length, &image_format))
+ return false;
+
+ {
+ /* TODO Move the following into CBDT struct when adding more formats. */
+
+ if (unlikely (image_offset > cbdt_len || cbdt_len - image_offset < image_length))
+ return false;
+
+ switch (image_format)
+ {
+ case 17: {
+ if (unlikely (image_length < OT::GlyphBitmapDataFormat17::min_size))
+ return false;
+
+ const OT::GlyphBitmapDataFormat17& glyphFormat17 =
+ OT::StructAtOffset<OT::GlyphBitmapDataFormat17> (this->cbdt, image_offset);
+ glyphFormat17.glyphMetrics.get_extents (extents);
+ }
+ break;
+ default:
+ // TODO: Support other image formats.
+ return false;
+ }
+ }
+
+ /* Convert to the font units. */
+ extents->x_bearing *= upem / (float) x_ppem;
+ extents->y_bearing *= upem / (float) y_ppem;
+ extents->width *= upem / (float) x_ppem;
+ extents->height *= upem / (float) y_ppem;
+
+ return true;
+ }
+};
+
+typedef bool (*hb_cmap_get_glyph_func_t) (const void *obj,
+ hb_codepoint_t codepoint,
+ hb_codepoint_t *glyph);
+
+template <typename Type>
+static inline bool get_glyph_from (const void *obj,
+ hb_codepoint_t codepoint,
+ hb_codepoint_t *glyph)
+{
+ const Type *typed_obj = (const Type *) obj;
+ return typed_obj->get_glyph (codepoint, glyph);
+}
+
+template <typename Type>
+static inline bool get_glyph_from_symbol (const void *obj,
+ hb_codepoint_t codepoint,
+ hb_codepoint_t *glyph)
+{
+ const Type *typed_obj = (const Type *) obj;
+ if (likely (typed_obj->get_glyph (codepoint, glyph)))
+ return true;
+
+ if (codepoint <= 0x00FFu)
+ {
+ /* For symbol-encoded OpenType fonts, we duplicate the
+ * U+F000..F0FF range at U+0000..U+00FF. That's what
+ * Windows seems to do, and that's hinted about at:
+ * http://www.microsoft.com/typography/otspec/recom.htm
+ * under "Non-Standard (Symbol) Fonts". */
+ return typed_obj->get_glyph (0xF000u + codepoint, glyph);
+ }
+
+ return false;
+}
+
+struct hb_ot_face_cmap_accelerator_t
+{
+ hb_cmap_get_glyph_func_t get_glyph_func;
+ const void *get_glyph_data;
+ OT::CmapSubtableFormat4::accelerator_t format4_accel;
+
+ const OT::CmapSubtableFormat14 *uvs_table;
+ hb_blob_t *blob;
+
+ inline void init (hb_face_t *face)
+ {
+ this->blob = OT::Sanitizer<OT::cmap>::sanitize (face->reference_table (HB_OT_TAG_cmap));
+ const OT::cmap *cmap = OT::Sanitizer<OT::cmap>::lock_instance (this->blob);
+ const OT::CmapSubtable *subtable = NULL;
+ const OT::CmapSubtableFormat14 *subtable_uvs = NULL;
+
+ bool symbol = false;
+ /* 32-bit subtables. */
+ if (!subtable) subtable = cmap->find_subtable (3, 10);
+ if (!subtable) subtable = cmap->find_subtable (0, 6);
+ if (!subtable) subtable = cmap->find_subtable (0, 4);
+ /* 16-bit subtables. */
+ if (!subtable) subtable = cmap->find_subtable (3, 1);
+ if (!subtable) subtable = cmap->find_subtable (0, 3);
+ if (!subtable) subtable = cmap->find_subtable (0, 2);
+ if (!subtable) subtable = cmap->find_subtable (0, 1);
+ if (!subtable) subtable = cmap->find_subtable (0, 0);
+ if (!subtable)
+ {
+ subtable = cmap->find_subtable (3, 0);
+ if (subtable) symbol = true;
+ }
+ /* Meh. */
+ if (!subtable) subtable = &OT::Null(OT::CmapSubtable);
+
+ /* UVS subtable. */
+ if (!subtable_uvs)
+ {
+ const OT::CmapSubtable *st = cmap->find_subtable (0, 5);
+ if (st && st->u.format == 14)
+ subtable_uvs = &st->u.format14;
+ }
+ /* Meh. */
+ if (!subtable_uvs) subtable_uvs = &OT::Null(OT::CmapSubtableFormat14);
+
+ this->uvs_table = subtable_uvs;
+
+ this->get_glyph_data = subtable;
+ if (unlikely (symbol))
+ this->get_glyph_func = get_glyph_from_symbol<OT::CmapSubtable>;
+ else
+ switch (subtable->u.format) {
+ /* Accelerate format 4 and format 12. */
+ default: this->get_glyph_func = get_glyph_from<OT::CmapSubtable>; break;
+ case 12: this->get_glyph_func = get_glyph_from<OT::CmapSubtableFormat12>; break;
+ case 4:
+ {
+ this->format4_accel.init (&subtable->u.format4);
+ this->get_glyph_data = &this->format4_accel;
+ this->get_glyph_func = this->format4_accel.get_glyph_func;
+ }
+ break;
+ }
+ }
+
+ inline void fini (void)
+ {
+ hb_blob_destroy (this->blob);
+ }
+
+ inline bool get_nominal_glyph (hb_codepoint_t unicode,
+ hb_codepoint_t *glyph) const
+ {
+ return this->get_glyph_func (this->get_glyph_data, unicode, glyph);
+ }
+
+ inline bool get_variation_glyph (hb_codepoint_t unicode,
+ hb_codepoint_t variation_selector,
+ hb_codepoint_t *glyph) const
+ {
+ switch (this->uvs_table->get_glyph_variant (unicode,
+ variation_selector,
+ glyph))
+ {
+ case OT::GLYPH_VARIANT_NOT_FOUND: return false;
+ case OT::GLYPH_VARIANT_FOUND: return true;
+ case OT::GLYPH_VARIANT_USE_DEFAULT: break;
+ }
+
+ return get_nominal_glyph (unicode, glyph);
+ }
+};
+
+template <typename T>
+struct hb_lazy_loader_t
+{
+ inline void init (hb_face_t *face_)
+ {
+ face = face_;
+ instance = NULL;
+ }
+
+ inline void fini (void)
+ {
+ if (instance && instance != &OT::Null(T))
+ {
+ instance->fini();
+ free (instance);
+ }
+ }
+
+ inline const T* operator-> (void) const
+ {
+ retry:
+ T *p = (T *) hb_atomic_ptr_get (&instance);
+ if (unlikely (!p))
+ {
+ p = (T *) calloc (1, sizeof (T));
+ if (unlikely (!p))
+ return &OT::Null(T);
+ p->init (face);
+ if (unlikely (!hb_atomic_ptr_cmpexch (const_cast<T **>(&instance), NULL, p)))
+ {
+ p->fini ();
+ goto retry;
+ }
+ }
+ return p;
+ }
+
+ private:
+ hb_face_t *face;
+ T *instance;
+};
+
+struct hb_ot_font_t
+{
+ hb_ot_face_cmap_accelerator_t cmap;
+ hb_ot_face_metrics_accelerator_t h_metrics;
+ hb_ot_face_metrics_accelerator_t v_metrics;
+ hb_lazy_loader_t<hb_ot_face_glyf_accelerator_t> glyf;
+ hb_lazy_loader_t<hb_ot_face_cbdt_accelerator_t> cbdt;
+};
+
+
+static hb_ot_font_t *
+_hb_ot_font_create (hb_face_t *face)
+{
+ hb_ot_font_t *ot_font = (hb_ot_font_t *) calloc (1, sizeof (hb_ot_font_t));
+
+ if (unlikely (!ot_font))
+ return NULL;
+
+ ot_font->cmap.init (face);
+ ot_font->h_metrics.init (face, HB_OT_TAG_hhea, HB_OT_TAG_hmtx, HB_OT_TAG_os2);
+ ot_font->v_metrics.init (face, HB_OT_TAG_vhea, HB_OT_TAG_vmtx, HB_TAG_NONE,
+ ot_font->h_metrics.ascender - ot_font->h_metrics.descender); /* TODO Can we do this lazily? */
+ ot_font->glyf.init (face);
+ ot_font->cbdt.init (face);
+
+ return ot_font;
+}
+
+static void
+_hb_ot_font_destroy (hb_ot_font_t *ot_font)
+{
+ ot_font->cmap.fini ();
+ ot_font->h_metrics.fini ();
+ ot_font->v_metrics.fini ();
+ ot_font->glyf.fini ();
+ ot_font->cbdt.fini ();
+
+ free (ot_font);
+}
+
+
+static hb_bool_t
+hb_ot_get_nominal_glyph (hb_font_t *font HB_UNUSED,
+ void *font_data,
+ hb_codepoint_t unicode,
+ hb_codepoint_t *glyph,
+ void *user_data HB_UNUSED)
+
+{
+ const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;
+ return ot_font->cmap.get_nominal_glyph (unicode, glyph);
+}
+
+static hb_bool_t
+hb_ot_get_variation_glyph (hb_font_t *font HB_UNUSED,
+ void *font_data,
+ hb_codepoint_t unicode,
+ hb_codepoint_t variation_selector,
+ hb_codepoint_t *glyph,
+ void *user_data HB_UNUSED)
+{
+ const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;
+ return ot_font->cmap.get_variation_glyph (unicode, variation_selector, glyph);
+}
+
+static hb_position_t
+hb_ot_get_glyph_h_advance (hb_font_t *font HB_UNUSED,
+ void *font_data,
+ hb_codepoint_t glyph,
+ void *user_data HB_UNUSED)
+{
+ const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;
+ return font->em_scale_x (ot_font->h_metrics.get_advance (glyph));
+}
+
+static hb_position_t
+hb_ot_get_glyph_v_advance (hb_font_t *font HB_UNUSED,
+ void *font_data,
+ hb_codepoint_t glyph,
+ void *user_data HB_UNUSED)
+{
+ const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;
+ return font->em_scale_y (-(int) ot_font->v_metrics.get_advance (glyph));
+}
+
+static hb_bool_t
+hb_ot_get_glyph_extents (hb_font_t *font HB_UNUSED,
+ void *font_data,
+ hb_codepoint_t glyph,
+ hb_glyph_extents_t *extents,
+ void *user_data HB_UNUSED)
+{
+ const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;
+ bool ret = ot_font->glyf->get_extents (glyph, extents);
+ if (!ret)
+ ret = ot_font->cbdt->get_extents (glyph, extents);
+ extents->x_bearing = font->em_scale_x (extents->x_bearing);
+ extents->y_bearing = font->em_scale_y (extents->y_bearing);
+ extents->width = font->em_scale_x (extents->width);
+ extents->height = font->em_scale_y (extents->height);
+ return ret;
+}
+
+static hb_bool_t
+hb_ot_get_font_h_extents (hb_font_t *font HB_UNUSED,
+ void *font_data,
+ hb_font_extents_t *metrics,
+ void *user_data HB_UNUSED)
+{
+ const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;
+ metrics->ascender = font->em_scale_y (ot_font->h_metrics.ascender);
+ metrics->descender = font->em_scale_y (ot_font->h_metrics.descender);
+ metrics->line_gap = font->em_scale_y (ot_font->h_metrics.line_gap);
+ return ot_font->h_metrics.has_font_extents;
+}
+
+static hb_bool_t
+hb_ot_get_font_v_extents (hb_font_t *font HB_UNUSED,
+ void *font_data,
+ hb_font_extents_t *metrics,
+ void *user_data HB_UNUSED)
+{
+ const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;
+ metrics->ascender = font->em_scale_x (ot_font->v_metrics.ascender);
+ metrics->descender = font->em_scale_x (ot_font->v_metrics.descender);
+ metrics->line_gap = font->em_scale_x (ot_font->v_metrics.line_gap);
+ return ot_font->v_metrics.has_font_extents;
+}
+
+static hb_font_funcs_t *static_ot_funcs = NULL;
+
+#ifdef HB_USE_ATEXIT
+static
+void free_static_ot_funcs (void)
+{
+ hb_font_funcs_destroy (static_ot_funcs);
+}
+#endif
+
+static hb_font_funcs_t *
+_hb_ot_get_font_funcs (void)
+{
+retry:
+ hb_font_funcs_t *funcs = (hb_font_funcs_t *) hb_atomic_ptr_get (&static_ot_funcs);
+
+ if (unlikely (!funcs))
+ {
+ funcs = hb_font_funcs_create ();
+
+ hb_font_funcs_set_font_h_extents_func (funcs, hb_ot_get_font_h_extents, NULL, NULL);
+ hb_font_funcs_set_font_v_extents_func (funcs, hb_ot_get_font_v_extents, NULL, NULL);
+ hb_font_funcs_set_nominal_glyph_func (funcs, hb_ot_get_nominal_glyph, NULL, NULL);
+ hb_font_funcs_set_variation_glyph_func (funcs, hb_ot_get_variation_glyph, NULL, NULL);
+ hb_font_funcs_set_glyph_h_advance_func (funcs, hb_ot_get_glyph_h_advance, NULL, NULL);
+ hb_font_funcs_set_glyph_v_advance_func (funcs, hb_ot_get_glyph_v_advance, NULL, NULL);
+ //hb_font_funcs_set_glyph_h_origin_func (funcs, hb_ot_get_glyph_h_origin, NULL, NULL);
+ //hb_font_funcs_set_glyph_v_origin_func (funcs, hb_ot_get_glyph_v_origin, NULL, NULL);
+ //hb_font_funcs_set_glyph_h_kerning_func (funcs, hb_ot_get_glyph_h_kerning, NULL, NULL); TODO
+ //hb_font_funcs_set_glyph_v_kerning_func (funcs, hb_ot_get_glyph_v_kerning, NULL, NULL);
+ hb_font_funcs_set_glyph_extents_func (funcs, hb_ot_get_glyph_extents, NULL, NULL);
+ //hb_font_funcs_set_glyph_contour_point_func (funcs, hb_ot_get_glyph_contour_point, NULL, NULL); TODO
+ //hb_font_funcs_set_glyph_name_func (funcs, hb_ot_get_glyph_name, NULL, NULL); TODO
+ //hb_font_funcs_set_glyph_from_name_func (funcs, hb_ot_get_glyph_from_name, NULL, NULL); TODO
+
+ hb_font_funcs_make_immutable (funcs);
+
+ if (!hb_atomic_ptr_cmpexch (&static_ot_funcs, NULL, funcs)) {
+ hb_font_funcs_destroy (funcs);
+ goto retry;
+ }
+
+#ifdef HB_USE_ATEXIT
+ atexit (free_static_ot_funcs); /* First person registers atexit() callback. */
+#endif
+ };
+
+ return funcs;
+}
+
+
+/**
+ * hb_ot_font_set_funcs:
+ *
+ * Since: 0.9.28
+ **/
+void
+hb_ot_font_set_funcs (hb_font_t *font)
+{
+ hb_ot_font_t *ot_font = _hb_ot_font_create (font->face);
+ if (unlikely (!ot_font))
+ return;
+
+ hb_font_set_funcs (font,
+ _hb_ot_get_font_funcs (),
+ ot_font,
+ (hb_destroy_func_t) _hb_ot_font_destroy);
+}