harfbuzz/src/hb-ot-font.cc

301 lines
9.8 KiB
C++

/*
* 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.hh"
#include "hb-ot.h"
#include "hb-font.hh"
#include "hb-machinery.hh"
#include "hb-ot-face.hh"
#include "hb-ot-cmap-table.hh"
#include "hb-ot-hmtx-table.hh"
#include "hb-ot-kern-table.hh"
#include "hb-ot-post-table.hh"
#include "hb-ot-glyf-table.hh"
#include "hb-ot-vorg-table.hh"
#include "hb-ot-color-cbdt-table.hh"
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_face_data_t *ot_face = (const hb_ot_face_data_t *) font_data;
return ot_face->cmap.get ()->get_nominal_glyph (unicode, glyph);
}
static unsigned int
hb_ot_get_nominal_glyphs (hb_font_t *font HB_UNUSED,
void *font_data,
unsigned int count,
const hb_codepoint_t *first_unicode,
unsigned int unicode_stride,
hb_codepoint_t *first_glyph,
unsigned int glyph_stride,
void *user_data HB_UNUSED)
{
const hb_ot_face_data_t *ot_face = (const hb_ot_face_data_t *) font_data;
const OT::cmap_accelerator_t &cmap = *ot_face->cmap.get ();
unsigned int done;
for (done = 0;
done < count && cmap.get_nominal_glyph (*first_unicode, first_glyph);
done++)
{
first_unicode = &StructAtOffset<hb_codepoint_t> (first_unicode, unicode_stride);
first_glyph = &StructAtOffset<hb_codepoint_t> (first_glyph, glyph_stride);
}
return done;
}
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_face_data_t *ot_face = (const hb_ot_face_data_t *) font_data;
return ot_face->cmap.get ()->get_variation_glyph (unicode, variation_selector, glyph);
}
static void
hb_ot_get_glyph_h_advances (hb_font_t* font, void* font_data,
unsigned count,
const hb_codepoint_t *first_glyph,
unsigned glyph_stride,
hb_position_t *first_advance,
unsigned advance_stride,
void *user_data HB_UNUSED)
{
const hb_ot_face_data_t *ot_face = (const hb_ot_face_data_t *) font_data;
const OT::hmtx_accelerator_t &hmtx = *ot_face->hmtx.get ();
for (unsigned int i = 0; i < count; i++)
{
*first_advance = font->em_scale_x (hmtx.get_advance (*first_glyph, font));
first_glyph = &StructAtOffset<hb_codepoint_t> (first_glyph, glyph_stride);
first_advance = &StructAtOffset<hb_position_t> (first_advance, advance_stride);
}
}
static void
hb_ot_get_glyph_v_advances (hb_font_t* font, void* font_data,
unsigned count,
const hb_codepoint_t *first_glyph,
unsigned glyph_stride,
hb_position_t *first_advance,
unsigned advance_stride,
void *user_data HB_UNUSED)
{
const hb_ot_face_data_t *ot_face = (const hb_ot_face_data_t *) font_data;
const OT::vmtx_accelerator_t &vmtx = *ot_face->vmtx.get ();
for (unsigned int i = 0; i < count; i++)
{
*first_advance = font->em_scale_y (-(int) vmtx.get_advance (*first_glyph, font));
first_glyph = &StructAtOffset<hb_codepoint_t> (first_glyph, glyph_stride);
first_advance = &StructAtOffset<hb_position_t> (first_advance, advance_stride);
}
}
static hb_bool_t
hb_ot_get_glyph_v_origin (hb_font_t *font,
void *font_data,
hb_codepoint_t glyph,
hb_position_t *x,
hb_position_t *y,
void *user_data HB_UNUSED)
{
const hb_ot_face_data_t *ot_face = (const hb_ot_face_data_t *) font_data;
*x = font->get_glyph_h_advance (glyph) / 2;
const OT::VORG &VORG = *ot_face->VORG.get ();
if (VORG.has_data ())
{
*y = font->em_scale_y (VORG.get_y_origin (glyph));
return true;
}
hb_glyph_extents_t extents = {0};
if (ot_face->glyf->get_extents (glyph, &extents))
{
const OT::vmtx_accelerator_t &vmtx = *ot_face->vmtx.get ();
hb_position_t tsb = vmtx.get_side_bearing (glyph);
*y = font->em_scale_y (extents.y_bearing + tsb);
return true;
}
hb_font_extents_t font_extents;
font->get_h_extents_with_fallback (&font_extents);
*y = font_extents.ascender;
return true;
}
static hb_bool_t
hb_ot_get_glyph_extents (hb_font_t *font,
void *font_data,
hb_codepoint_t glyph,
hb_glyph_extents_t *extents,
void *user_data HB_UNUSED)
{
const hb_ot_face_data_t *ot_face = (const hb_ot_face_data_t *) font_data;
bool ret = ot_face->glyf->get_extents (glyph, extents);
if (!ret)
ret = ot_face->CBDT->get_extents (glyph, extents);
// TODO Hook up side-bearings variations.
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_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)
{
const hb_ot_face_data_t *ot_face = (const hb_ot_face_data_t *) font_data;
return ot_face->post->get_glyph_name (glyph, name, size);
}
static hb_bool_t
hb_ot_get_glyph_from_name (hb_font_t *font HB_UNUSED,
void *font_data,
const char *name, int len,
hb_codepoint_t *glyph,
void *user_data HB_UNUSED)
{
const hb_ot_face_data_t *ot_face = (const hb_ot_face_data_t *) font_data;
return ot_face->post->get_glyph_from_name (name, len, glyph);
}
static hb_bool_t
hb_ot_get_font_h_extents (hb_font_t *font,
void *font_data,
hb_font_extents_t *metrics,
void *user_data HB_UNUSED)
{
const hb_ot_face_data_t *ot_face = (const hb_ot_face_data_t *) font_data;
const OT::hmtx_accelerator_t &hmtx = *ot_face->hmtx.get ();
metrics->ascender = font->em_scale_y (hmtx.ascender);
metrics->descender = font->em_scale_y (hmtx.descender);
metrics->line_gap = font->em_scale_y (hmtx.line_gap);
// TODO Hook up variations.
return hmtx.has_font_extents;
}
static hb_bool_t
hb_ot_get_font_v_extents (hb_font_t *font,
void *font_data,
hb_font_extents_t *metrics,
void *user_data HB_UNUSED)
{
const hb_ot_face_data_t *ot_face = (const hb_ot_face_data_t *) font_data;
const OT::vmtx_accelerator_t &vmtx = *ot_face->vmtx.get ();
metrics->ascender = font->em_scale_x (vmtx.ascender);
metrics->descender = font->em_scale_x (vmtx.descender);
metrics->line_gap = font->em_scale_x (vmtx.line_gap);
// TODO Hook up variations.
return vmtx.has_font_extents;
}
#ifdef HB_USE_ATEXIT
static void free_static_ot_funcs (void);
#endif
static struct hb_ot_font_funcs_lazy_loader_t : hb_font_funcs_lazy_loader_t<hb_ot_font_funcs_lazy_loader_t>
{
static inline hb_font_funcs_t *create (void)
{
hb_font_funcs_t *funcs = hb_font_funcs_create ();
hb_font_funcs_set_font_h_extents_func (funcs, hb_ot_get_font_h_extents, nullptr, nullptr);
hb_font_funcs_set_font_v_extents_func (funcs, hb_ot_get_font_v_extents, nullptr, nullptr);
hb_font_funcs_set_nominal_glyph_func (funcs, hb_ot_get_nominal_glyph, nullptr, nullptr);
hb_font_funcs_set_nominal_glyphs_func (funcs, hb_ot_get_nominal_glyphs, nullptr, nullptr);
hb_font_funcs_set_variation_glyph_func (funcs, hb_ot_get_variation_glyph, nullptr, nullptr);
hb_font_funcs_set_glyph_h_advances_func (funcs, hb_ot_get_glyph_h_advances, nullptr, nullptr);
hb_font_funcs_set_glyph_v_advances_func (funcs, hb_ot_get_glyph_v_advances, nullptr, nullptr);
//hb_font_funcs_set_glyph_h_origin_func (funcs, hb_ot_get_glyph_h_origin, nullptr, nullptr);
hb_font_funcs_set_glyph_v_origin_func (funcs, hb_ot_get_glyph_v_origin, nullptr, nullptr);
hb_font_funcs_set_glyph_extents_func (funcs, hb_ot_get_glyph_extents, nullptr, nullptr);
//hb_font_funcs_set_glyph_contour_point_func (funcs, hb_ot_get_glyph_contour_point, nullptr, nullptr);
hb_font_funcs_set_glyph_name_func (funcs, hb_ot_get_glyph_name, nullptr, nullptr);
hb_font_funcs_set_glyph_from_name_func (funcs, hb_ot_get_glyph_from_name, nullptr, nullptr);
hb_font_funcs_make_immutable (funcs);
#ifdef HB_USE_ATEXIT
atexit (free_static_ot_funcs);
#endif
return funcs;
}
} static_ot_funcs;
#ifdef HB_USE_ATEXIT
static
void free_static_ot_funcs (void)
{
static_ot_funcs.free_instance ();
}
#endif
static hb_font_funcs_t *
_hb_ot_get_font_funcs (void)
{
return static_ot_funcs.get_unconst ();
}
/**
* hb_ot_font_set_funcs:
*
* Since: 0.9.28
**/
void
hb_ot_font_set_funcs (hb_font_t *font)
{
if (unlikely (!hb_ot_shaper_face_data_ensure (font->face))) return;
hb_ot_face_data_t *ot_face = hb_ot_face_data (font->face);
hb_font_set_funcs (font,
_hb_ot_get_font_funcs (),
ot_face,
nullptr);
}