harfbuzz/src/hb-ot-font.cc

340 lines
11 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"
#ifndef HB_NO_OT_FONT
#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-glyf-table.hh"
#include "hb-ot-cff1-table.hh"
#include "hb-ot-cff2-table.hh"
#include "hb-ot-hmtx-table.hh"
#include "hb-ot-os2-table.hh"
#include "hb-ot-post-table.hh"
#include "hb-ot-stat-table.hh" // Just so we compile it; unused otherwise.
#include "hb-ot-vorg-table.hh"
#include "hb-ot-color-cbdt-table.hh"
#include "hb-ot-color-sbix-table.hh"
/**
* SECTION:hb-ot-font
* @title: hb-ot-font
* @short_description: OpenType font implementation
* @include: hb-ot.h
*
* Functions for using OpenType fonts with hb_shape(). Note that fonts returned
* by hb_font_create() default to using these functions, so most clients would
* never need to call these functions directly.
**/
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_t *ot_face = (const hb_ot_face_t *) font_data;
return ot_face->cmap->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_t *ot_face = (const hb_ot_face_t *) font_data;
return ot_face->cmap->get_nominal_glyphs (count,
first_unicode, unicode_stride,
first_glyph, glyph_stride);
}
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_t *ot_face = (const hb_ot_face_t *) font_data;
return ot_face->cmap->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_t *ot_face = (const hb_ot_face_t *) font_data;
const OT::hmtx_accelerator_t &hmtx = *ot_face->hmtx;
for (unsigned int i = 0; i < count; i++)
{
*first_advance = font->em_scale_x (hmtx.get_advance (*first_glyph, font));
first_glyph = &StructAtOffsetUnaligned<hb_codepoint_t> (first_glyph, glyph_stride);
first_advance = &StructAtOffsetUnaligned<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_t *ot_face = (const hb_ot_face_t *) font_data;
const OT::vmtx_accelerator_t &vmtx = *ot_face->vmtx;
for (unsigned int i = 0; i < count; i++)
{
*first_advance = font->em_scale_y (-(int) vmtx.get_advance (*first_glyph, font));
first_glyph = &StructAtOffsetUnaligned<hb_codepoint_t> (first_glyph, glyph_stride);
first_advance = &StructAtOffsetUnaligned<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_t *ot_face = (const hb_ot_face_t *) font_data;
*x = font->get_glyph_h_advance (glyph) / 2;
#ifndef HB_NO_OT_FONT_CFF
const OT::VORG &VORG = *ot_face->VORG;
if (VORG.has_data ())
{
*y = font->em_scale_y (VORG.get_y_origin (glyph));
return true;
}
#endif
hb_glyph_extents_t extents = {0};
if (ot_face->glyf->get_extents (font, glyph, &extents))
{
const OT::vmtx_accelerator_t &vmtx = *ot_face->vmtx;
hb_position_t tsb = vmtx.get_side_bearing (font, glyph);
*y = extents.y_bearing + font->em_scale_y (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_t *ot_face = (const hb_ot_face_t *) font_data;
#if !defined(HB_NO_OT_FONT_BITMAP) && !defined(HB_NO_COLOR)
if (ot_face->sbix->get_extents (font, glyph, extents)) return true;
#endif
if (ot_face->glyf->get_extents (font, glyph, extents)) return true;
#ifndef HB_NO_OT_FONT_CFF
if (ot_face->cff1->get_extents (font, glyph, extents)) return true;
if (ot_face->cff2->get_extents (font, glyph, extents)) return true;
#endif
#if !defined(HB_NO_OT_FONT_BITMAP) && !defined(HB_NO_COLOR)
if (ot_face->CBDT->get_extents (font, glyph, extents)) return true;
#endif
// TODO Hook up side-bearings variations.
return false;
}
#ifndef HB_NO_OT_FONT_GLYPH_NAMES
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_t *ot_face = (const hb_ot_face_t *) font_data;
if (ot_face->post->get_glyph_name (glyph, name, size)) return true;
#ifndef HB_NO_OT_FONT_CFF
if (ot_face->cff1->get_glyph_name (glyph, name, size)) return true;
#endif
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,
hb_codepoint_t *glyph,
void *user_data HB_UNUSED)
{
const hb_ot_face_t *ot_face = (const hb_ot_face_t *) font_data;
if (ot_face->post->get_glyph_from_name (name, len, glyph)) return true;
#ifndef HB_NO_OT_FONT_CFF
if (ot_face->cff1->get_glyph_from_name (name, len, glyph)) return true;
#endif
return false;
}
#endif
static hb_bool_t
hb_ot_get_font_h_extents (hb_font_t *font,
void *font_data HB_UNUSED,
hb_font_extents_t *metrics,
void *user_data HB_UNUSED)
{
return _hb_ot_metrics_get_position_common (font, HB_OT_METRICS_TAG_HORIZONTAL_ASCENDER, &metrics->ascender) &&
_hb_ot_metrics_get_position_common (font, HB_OT_METRICS_TAG_HORIZONTAL_DESCENDER, &metrics->descender) &&
_hb_ot_metrics_get_position_common (font, HB_OT_METRICS_TAG_HORIZONTAL_LINE_GAP, &metrics->line_gap);
}
static hb_bool_t
hb_ot_get_font_v_extents (hb_font_t *font,
void *font_data HB_UNUSED,
hb_font_extents_t *metrics,
void *user_data HB_UNUSED)
{
return _hb_ot_metrics_get_position_common (font, HB_OT_METRICS_TAG_VERTICAL_ASCENDER, &metrics->ascender) &&
_hb_ot_metrics_get_position_common (font, HB_OT_METRICS_TAG_VERTICAL_DESCENDER, &metrics->descender) &&
_hb_ot_metrics_get_position_common (font, HB_OT_METRICS_TAG_VERTICAL_LINE_GAP, &metrics->line_gap);
}
#if HB_USE_ATEXIT
static void free_static_ot_funcs ();
#endif
static struct hb_ot_font_funcs_lazy_loader_t : hb_font_funcs_lazy_loader_t<hb_ot_font_funcs_lazy_loader_t>
{
static hb_font_funcs_t *create ()
{
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);
#ifndef HB_NO_OT_FONT_GLYPH_NAMES
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);
#endif
hb_font_funcs_make_immutable (funcs);
#if HB_USE_ATEXIT
atexit (free_static_ot_funcs);
#endif
return funcs;
}
} static_ot_funcs;
#if HB_USE_ATEXIT
static
void free_static_ot_funcs ()
{
static_ot_funcs.free_instance ();
}
#endif
static hb_font_funcs_t *
_hb_ot_get_font_funcs ()
{
return static_ot_funcs.get_unconst ();
}
/**
* hb_ot_font_set_funcs:
* @font: #hb_font_t to work upon
*
* Sets the font functions to use when working with @font.
*
* Since: 0.9.28
**/
void
hb_ot_font_set_funcs (hb_font_t *font)
{
hb_font_set_funcs (font,
_hb_ot_get_font_funcs (),
&font->face->table,
nullptr);
}
#ifndef HB_NO_VAR
int
_glyf_get_side_bearing_var (hb_font_t *font, hb_codepoint_t glyph, bool is_vertical)
{
return font->face->table.glyf->get_side_bearing_var (font, glyph, is_vertical);
}
unsigned
_glyf_get_advance_var (hb_font_t *font, hb_codepoint_t glyph, bool is_vertical)
{
return font->face->table.glyf->get_advance_var (font, glyph, is_vertical);
}
#endif
#endif