/*
* 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-hhea-table.hh"
#include "hb-ot-hmtx-table.hh"
struct hb_ot_font_t
{
unsigned int num_glyphs;
unsigned int num_hmetrics;
const OT::hmtx *hmtx;
hb_blob_t *hmtx_blob;
const OT::CmapSubtable *cmap;
const OT::CmapSubtable *cmap_uvs;
hb_blob_t *cmap_blob;
};
static hb_ot_font_t *
_hb_ot_font_create (hb_font_t *font)
{
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->num_glyphs = font->face->get_num_glyphs ();
{
hb_blob_t *hhea_blob = OT::Sanitizer<OT::hhea>::sanitize (font->face->reference_table (HB_OT_TAG_hhea));
const OT::hhea *hhea = OT::Sanitizer<OT::hhea>::lock_instance (hhea_blob);
ot_font->num_hmetrics = hhea->numberOfHMetrics;
hb_blob_destroy (hhea_blob);
}
ot_font->hmtx_blob = OT::Sanitizer<OT::hmtx>::sanitize (font->face->reference_table (HB_OT_TAG_hmtx));
if (unlikely (!ot_font->num_hmetrics ||
2 * (ot_font->num_hmetrics + ot_font->num_glyphs) < hb_blob_get_length (ot_font->hmtx_blob)))
{
hb_blob_destroy (ot_font->hmtx_blob);
free (ot_font);
return NULL;
}
ot_font->hmtx = OT::Sanitizer<OT::hmtx>::lock_instance (ot_font->hmtx_blob);
ot_font->cmap_blob = OT::Sanitizer<OT::cmap>::sanitize (font->face->reference_table (HB_OT_TAG_cmap));
const OT::cmap *cmap = OT::Sanitizer<OT::cmap>::lock_instance (ot_font->cmap_blob);
const OT::CmapSubtable *subtable = NULL;
const OT::CmapSubtable *subtable_uvs = NULL;
/* 32-bit subtables. */
if (!subtable) subtable = cmap->find_subtable (0, 6);
if (!subtable) subtable = cmap->find_subtable (0, 4);
if (!subtable) subtable = cmap->find_subtable (3, 10);
/* 16-bit subtables. */
if (!subtable) subtable = cmap->find_subtable (0, 3);
if (!subtable) subtable = cmap->find_subtable (3, 1);
/* Meh. */
if (!subtable) subtable = &OT::Null(OT::CmapSubtable);
/* UVS subtable. */
if (!subtable_uvs) subtable_uvs = cmap->find_subtable (0, 5);
/* Meh. */
if (!subtable_uvs) subtable_uvs = &OT::Null(OT::CmapSubtable);
ot_font->cmap = subtable;
ot_font->cmap_uvs = subtable_uvs;
return ot_font;
}
static void
_hb_ot_font_destroy (hb_ot_font_t *ot_font)
{
hb_blob_destroy (ot_font->cmap_blob);
hb_blob_destroy (ot_font->hmtx_blob);
free (ot_font);
}
static hb_bool_t
hb_ot_get_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;
if (unlikely (variation_selector))
{
switch (ot_font->cmap_uvs->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 ot_font->cmap->get_glyph (unicode, 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;
if (unlikely (glyph >= ot_font->num_glyphs))
return 0; /* Maybe better to return notdef's advance instead? */
if (glyph >= ot_font->num_hmetrics)
glyph = ot_font->num_hmetrics - 1;
return font->em_scale_x (ot_font->hmtx->longHorMetric[glyph].advanceWidth);
}
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)
{
/* TODO */
return 0;
}
static hb_bool_t
hb_ot_get_glyph_h_origin (hb_font_t *font HB_UNUSED,
void *font_data HB_UNUSED,
hb_codepoint_t glyph HB_UNUSED,
hb_position_t *x HB_UNUSED,
hb_position_t *y HB_UNUSED,
void *user_data HB_UNUSED)
{
/* We always work in the horizontal coordinates. */
return true;
}
static hb_bool_t
hb_ot_get_glyph_v_origin (hb_font_t *font HB_UNUSED,
void *font_data,
hb_codepoint_t glyph,
hb_position_t *x,
hb_position_t *y,
void *user_data HB_UNUSED)
{
/* TODO */
return false;
}
static hb_position_t
hb_ot_get_glyph_h_kerning (hb_font_t *font,
void *font_data,
hb_codepoint_t left_glyph,
hb_codepoint_t right_glyph,
void *user_data HB_UNUSED)
{
/* TODO */
return 0;
}
static hb_position_t
hb_ot_get_glyph_v_kerning (hb_font_t *font HB_UNUSED,
void *font_data HB_UNUSED,
hb_codepoint_t top_glyph HB_UNUSED,
hb_codepoint_t bottom_glyph HB_UNUSED,
void *user_data HB_UNUSED)
{
return 0;
}
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)
{
/* TODO */
return false;
}
static hb_bool_t
hb_ot_get_glyph_contour_point (hb_font_t *font HB_UNUSED,
void *font_data,
hb_codepoint_t glyph,
unsigned int point_index,
hb_position_t *x,
hb_position_t *y,
void *user_data HB_UNUSED)
{
/* TODO */
return false;
}
static hb_bool_t
hb_ot_get_glyph_name (hb_font_t *font HB_UNUSED,
void *font_data,
hb_codepoint_t glyph,
char *name, unsigned int size,
void *user_data HB_UNUSED)
{
/* TODO */
return false;
}
static hb_bool_t
hb_ot_get_glyph_from_name (hb_font_t *font HB_UNUSED,
void *font_data,
const char *name, int len, /* -1 means nul-terminated */
hb_codepoint_t *glyph,
void *user_data HB_UNUSED)
{
/* TODO */
return false;
}
static hb_font_funcs_t *
_hb_ot_get_font_funcs (void)
{
static const hb_font_funcs_t ot_ffuncs = {
HB_OBJECT_HEADER_STATIC,
true, /* immutable */
{
#define HB_FONT_FUNC_IMPLEMENT(name) hb_ot_get_##name,
HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
#undef HB_FONT_FUNC_IMPLEMENT
}
};
return const_cast<hb_font_funcs_t *> (&ot_ffuncs);
}
void
hb_ot_font_set_funcs (hb_font_t *font)
{
hb_ot_font_t *ot_font = _hb_ot_font_create (font);
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);
}