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/*
* Copyright © 2009 Red Hat, Inc.
* Copyright © 2009 Keith Stribley
* Copyright © 2015 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.
*
* Red Hat Author(s): Behdad Esfahbod
* Google Author(s): Behdad Esfahbod
*/
#include "hb.hh"
#ifdef HAVE_FREETYPE
#include "hb-ft.h"
#include "hb-font.hh"
#include "hb-machinery.hh"
#include "hb-cache.hh"
#include FT_ADVANCES_H
#include FT_MULTIPLE_MASTERS_H
#include FT_TRUETYPE_TABLES_H
/**
* SECTION:hb-ft
* @title: hb-ft
* @short_description: FreeType integration
* @include: hb-ft.h
*
* Functions for using HarfBuzz with the FreeType library.
*
* HarfBuzz supports using FreeType to provide face and
* font data.
*
* <note>Note that FreeType is not thread-safe, therefore these
* functions are not thread-safe either.</note>
**/
/* TODO:
*
* In general, this file does a fine job of what it's supposed to do.
* There are, however, things that need more work:
*
* - FreeType works in 26.6 mode. Clients can decide to use that mode, and everything
* would work fine. However, we also abuse this API for performing in font-space,
* but don't pass the correct flags to FreeType. We just abuse the no-hinting mode
* for that, such that no rounding etc happens. As such, we don't set ppem, and
* pass NO_HINTING as load_flags. Would be much better to use NO_SCALE, and scale
* ourselves.
*
* - We don't handle / allow for emboldening / obliqueing.
*
* - In the future, we should add constructors to create fonts in font space?
*/
struct hb_ft_font_t
{
mutable hb_mutex_t lock;
FT_Face ft_face;
int load_flags;
bool symbol; /* Whether selected cmap is symbol cmap. */
bool unref; /* Whether to destroy ft_face when done. */
mutable int cached_x_scale;
mutable hb_advance_cache_t advance_cache;
};
static hb_ft_font_t *
_hb_ft_font_create (FT_Face ft_face, bool symbol, bool unref)
{
hb_ft_font_t *ft_font = (hb_ft_font_t *) hb_calloc (1, sizeof (hb_ft_font_t));
if (unlikely (!ft_font)) return nullptr;
ft_font->lock.init ();
ft_font->ft_face = ft_face;
ft_font->symbol = symbol;
ft_font->unref = unref;
ft_font->load_flags = FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING;
ft_font->cached_x_scale = 0;
ft_font->advance_cache.init ();
return ft_font;
}
static void
_hb_ft_face_destroy (void *data)
{
FT_Done_Face ((FT_Face) data);
}
static void
_hb_ft_font_destroy (void *data)
{
hb_ft_font_t *ft_font = (hb_ft_font_t *) data;
ft_font->advance_cache.fini ();
if (ft_font->unref)
_hb_ft_face_destroy (ft_font->ft_face);
ft_font->lock.fini ();
hb_free (ft_font);
}
/**
* hb_ft_font_set_load_flags:
* @font: #hb_font_t to work upon
* @load_flags: The FreeType load flags to set
*
* Sets the FT_Load_Glyph load flags for the specified #hb_font_t.
*
* For more information, see
* https://www.freetype.org/freetype2/docs/reference/ft2-base_interface.html#ft_load_xxx
*
* Since: 1.0.5
**/
void
hb_ft_font_set_load_flags (hb_font_t *font, int load_flags)
{
if (hb_object_is_immutable (font))
return;
if (unlikely (font->destroy != (hb_destroy_func_t) _hb_ft_font_destroy))
return;
hb_ft_font_t *ft_font = (hb_ft_font_t *) font->user_data;
ft_font->load_flags = load_flags;
}
/**
* hb_ft_font_get_load_flags:
* @font: #hb_font_t to work upon
*
* Fetches the FT_Load_Glyph load flags of the specified #hb_font_t.
*
* For more information, see
* https://www.freetype.org/freetype2/docs/reference/ft2-base_interface.html#ft_load_xxx
*
* Return value: FT_Load_Glyph flags found
*
* Since: 1.0.5
**/
int
hb_ft_font_get_load_flags (hb_font_t *font)
{
if (unlikely (font->destroy != (hb_destroy_func_t) _hb_ft_font_destroy))
return 0;
const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font->user_data;
return ft_font->load_flags;
}
/**
* hb_ft_font_get_face:
* @font: #hb_font_t to work upon
*
* Fetches the FT_Face associated with the specified #hb_font_t
* font object.
*
* Return value: (nullable): the FT_Face found or %NULL
*
* Since: 0.9.2
**/
FT_Face
hb_ft_font_get_face (hb_font_t *font)
{
if (unlikely (font->destroy != (hb_destroy_func_t) _hb_ft_font_destroy))
return nullptr;
const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font->user_data;
return ft_font->ft_face;
}
/**
* hb_ft_font_lock_face:
* @font: #hb_font_t to work upon
*
* Gets the FT_Face associated with @font, This face will be kept around until
* you call hb_ft_font_unlock_face().
*
* Return value: (nullable): the FT_Face associated with @font or %NULL
* Since: 2.6.5
**/
FT_Face
hb_ft_font_lock_face (hb_font_t *font)
{
if (unlikely (font->destroy != (hb_destroy_func_t) _hb_ft_font_destroy))
return nullptr;
const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font->user_data;
ft_font->lock.lock ();
return ft_font->ft_face;
}
/**
* hb_ft_font_unlock_face:
* @font: #hb_font_t to work upon
*
* Releases an FT_Face previously obtained with hb_ft_font_lock_face().
*
* Since: 2.6.5
**/
void
hb_ft_font_unlock_face (hb_font_t *font)
{
if (unlikely (font->destroy != (hb_destroy_func_t) _hb_ft_font_destroy))
return;
const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font->user_data;
ft_font->lock.unlock ();
}
static hb_bool_t
hb_ft_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_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
hb_lock_t lock (ft_font->lock);
unsigned int g = FT_Get_Char_Index (ft_font->ft_face, unicode);
if (unlikely (!g))
{
if (unlikely (ft_font->symbol) && unicode <= 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:
* https://docs.microsoft.com/en-us/typography/opentype/spec/recom
* under "Non-Standard (Symbol) Fonts". */
g = FT_Get_Char_Index (ft_font->ft_face, 0xF000u + unicode);
if (!g)
return false;
}
else
return false;
}
*glyph = g;
return true;
}
static unsigned int
hb_ft_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_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
hb_lock_t lock (ft_font->lock);
unsigned int done;
for (done = 0;
done < count && (*first_glyph = FT_Get_Char_Index (ft_font->ft_face, *first_unicode));
done++)
{
first_unicode = &StructAtOffsetUnaligned<hb_codepoint_t> (first_unicode, unicode_stride);
first_glyph = &StructAtOffsetUnaligned<hb_codepoint_t> (first_glyph, glyph_stride);
}
/* We don't need to do ft_font->symbol dance here, since HB calls the singular
* nominal_glyph() for what we don't handle here. */
return done;
}
static hb_bool_t
hb_ft_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_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
hb_lock_t lock (ft_font->lock);
unsigned int g = FT_Face_GetCharVariantIndex (ft_font->ft_face, unicode, variation_selector);
if (unlikely (!g))
return false;
*glyph = g;
return true;
}
static void
hb_ft_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_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
hb_lock_t lock (ft_font->lock);
FT_Face ft_face = ft_font->ft_face;
int load_flags = ft_font->load_flags;
int mult = font->x_scale < 0 ? -1 : +1;
if (font->x_scale != ft_font->cached_x_scale)
{
ft_font->advance_cache.clear ();
ft_font->cached_x_scale = font->x_scale;
}
for (unsigned int i = 0; i < count; i++)
{
FT_Fixed v = 0;
hb_codepoint_t glyph = *first_glyph;
unsigned int cv;
if (ft_font->advance_cache.get (glyph, &cv))
v = cv;
else
{
FT_Get_Advance (ft_face, glyph, load_flags, &v);
ft_font->advance_cache.set (glyph, v);
}
*first_advance = (v * mult + (1<<9)) >> 10;
first_glyph = &StructAtOffsetUnaligned<hb_codepoint_t> (first_glyph, glyph_stride);
first_advance = &StructAtOffsetUnaligned<hb_position_t> (first_advance, advance_stride);
}
}
static hb_position_t
hb_ft_get_glyph_v_advance (hb_font_t *font,
void *font_data,
hb_codepoint_t glyph,
void *user_data HB_UNUSED)
{
const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
hb_lock_t lock (ft_font->lock);
FT_Fixed v;
if (unlikely (FT_Get_Advance (ft_font->ft_face, glyph, ft_font->load_flags | FT_LOAD_VERTICAL_LAYOUT, &v)))
return 0;
if (font->y_scale < 0)
v = -v;
/* Note: FreeType's vertical metrics grows downward while other FreeType coordinates
* have a Y growing upward. Hence the extra negation. */
return (-v + (1<<9)) >> 10;
}
static hb_bool_t
hb_ft_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_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
hb_lock_t lock (ft_font->lock);
FT_Face ft_face = ft_font->ft_face;
if (unlikely (FT_Load_Glyph (ft_face, glyph, ft_font->load_flags)))
return false;
/* Note: FreeType's vertical metrics grows downward while other FreeType coordinates
* have a Y growing upward. Hence the extra negation. */
*x = ft_face->glyph->metrics.horiBearingX - ft_face->glyph->metrics.vertBearingX;
*y = ft_face->glyph->metrics.horiBearingY - (-ft_face->glyph->metrics.vertBearingY);
if (font->x_scale < 0)
*x = -*x;
if (font->y_scale < 0)
*y = -*y;
return true;
}
#ifndef HB_NO_OT_SHAPE_FALLBACK
static hb_position_t
hb_ft_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)
{
const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
FT_Vector kerningv;
FT_Kerning_Mode mode = font->x_ppem ? FT_KERNING_DEFAULT : FT_KERNING_UNFITTED;
if (FT_Get_Kerning (ft_font->ft_face, left_glyph, right_glyph, mode, &kerningv))
return 0;
return kerningv.x;
}
#endif
static hb_bool_t
hb_ft_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_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
hb_lock_t lock (ft_font->lock);
FT_Face ft_face = ft_font->ft_face;
if (unlikely (FT_Load_Glyph (ft_face, glyph, ft_font->load_flags)))
return false;
extents->x_bearing = ft_face->glyph->metrics.horiBearingX;
extents->y_bearing = ft_face->glyph->metrics.horiBearingY;
extents->width = ft_face->glyph->metrics.width;
extents->height = -ft_face->glyph->metrics.height;
if (font->x_scale < 0)
{
extents->x_bearing = -extents->x_bearing;
extents->width = -extents->width;
}
if (font->y_scale < 0)
{
extents->y_bearing = -extents->y_bearing;
extents->height = -extents->height;
}
return true;
}
static hb_bool_t
hb_ft_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)
{
const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
hb_lock_t lock (ft_font->lock);
FT_Face ft_face = ft_font->ft_face;
if (unlikely (FT_Load_Glyph (ft_face, glyph, ft_font->load_flags)))
return false;
if (unlikely (ft_face->glyph->format != FT_GLYPH_FORMAT_OUTLINE))
return false;
if (unlikely (point_index >= (unsigned int) ft_face->glyph->outline.n_points))
return false;
*x = ft_face->glyph->outline.points[point_index].x;
*y = ft_face->glyph->outline.points[point_index].y;
return true;
}
static hb_bool_t
hb_ft_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_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
hb_lock_t lock (ft_font->lock);
FT_Face ft_face = ft_font->ft_face;
hb_bool_t ret = !FT_Get_Glyph_Name (ft_face, glyph, name, size);
if (ret && (size && !*name))
ret = false;
return ret;
}
static hb_bool_t
hb_ft_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)
{
const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
hb_lock_t lock (ft_font->lock);
FT_Face ft_face = ft_font->ft_face;
if (len < 0)
*glyph = FT_Get_Name_Index (ft_face, (FT_String *) name);
else {
/* Make a nul-terminated version. */
char buf[128];
len = hb_min (len, (int) sizeof (buf) - 1);
strncpy (buf, name, len);
buf[len] = '\0';
*glyph = FT_Get_Name_Index (ft_face, buf);
}
if (*glyph == 0)
{
/* Check whether the given name was actually the name of glyph 0. */
char buf[128];
if (!FT_Get_Glyph_Name(ft_face, 0, buf, sizeof (buf)) &&
len < 0 ? !strcmp (buf, name) : !strncmp (buf, name, len))
return true;
}
return *glyph != 0;
}
static hb_bool_t
hb_ft_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_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
hb_lock_t lock (ft_font->lock);
FT_Face ft_face = ft_font->ft_face;
metrics->ascender = FT_MulFix(ft_face->ascender, ft_face->size->metrics.y_scale);
metrics->descender = FT_MulFix(ft_face->descender, ft_face->size->metrics.y_scale);
metrics->line_gap = FT_MulFix( ft_face->height, ft_face->size->metrics.y_scale ) - (metrics->ascender - metrics->descender);
if (font->y_scale < 0)
{
metrics->ascender = -metrics->ascender;
metrics->descender = -metrics->descender;
metrics->line_gap = -metrics->line_gap;
}
return true;
}
static inline void free_static_ft_funcs ();
static struct hb_ft_font_funcs_lazy_loader_t : hb_font_funcs_lazy_loader_t<hb_ft_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_ft_get_font_h_extents, nullptr, nullptr);
//hb_font_funcs_set_font_v_extents_func (funcs, hb_ft_get_font_v_extents, nullptr, nullptr);
hb_font_funcs_set_nominal_glyph_func (funcs, hb_ft_get_nominal_glyph, nullptr, nullptr);
hb_font_funcs_set_nominal_glyphs_func (funcs, hb_ft_get_nominal_glyphs, nullptr, nullptr);
hb_font_funcs_set_variation_glyph_func (funcs, hb_ft_get_variation_glyph, nullptr, nullptr);
hb_font_funcs_set_glyph_h_advances_func (funcs, hb_ft_get_glyph_h_advances, nullptr, nullptr);
hb_font_funcs_set_glyph_v_advance_func (funcs, hb_ft_get_glyph_v_advance, nullptr, nullptr);
//hb_font_funcs_set_glyph_h_origin_func (funcs, hb_ft_get_glyph_h_origin, nullptr, nullptr);
hb_font_funcs_set_glyph_v_origin_func (funcs, hb_ft_get_glyph_v_origin, nullptr, nullptr);
#ifndef HB_NO_OT_SHAPE_FALLBACK
hb_font_funcs_set_glyph_h_kerning_func (funcs, hb_ft_get_glyph_h_kerning, nullptr, nullptr);
#endif
//hb_font_funcs_set_glyph_v_kerning_func (funcs, hb_ft_get_glyph_v_kerning, nullptr, nullptr);
hb_font_funcs_set_glyph_extents_func (funcs, hb_ft_get_glyph_extents, nullptr, nullptr);
hb_font_funcs_set_glyph_contour_point_func (funcs, hb_ft_get_glyph_contour_point, nullptr, nullptr);
hb_font_funcs_set_glyph_name_func (funcs, hb_ft_get_glyph_name, nullptr, nullptr);
hb_font_funcs_set_glyph_from_name_func (funcs, hb_ft_get_glyph_from_name, nullptr, nullptr);
hb_font_funcs_make_immutable (funcs);
hb_atexit (free_static_ft_funcs);
return funcs;
}
} static_ft_funcs;
static inline
void free_static_ft_funcs ()
{
static_ft_funcs.free_instance ();
}
static hb_font_funcs_t *
_hb_ft_get_font_funcs ()
{
return static_ft_funcs.get_unconst ();
}
static void
_hb_ft_font_set_funcs (hb_font_t *font, FT_Face ft_face, bool unref)
{
bool symbol = ft_face->charmap && ft_face->charmap->encoding == FT_ENCODING_MS_SYMBOL;
hb_ft_font_t *ft_font = _hb_ft_font_create (ft_face, symbol, unref);
if (unlikely (!ft_font)) return;
hb_font_set_funcs (font,
_hb_ft_get_font_funcs (),
ft_font,
_hb_ft_font_destroy);
}
static hb_blob_t *
_hb_ft_reference_table (hb_face_t *face HB_UNUSED, hb_tag_t tag, void *user_data)
{
FT_Face ft_face = (FT_Face) user_data;
FT_Byte *buffer;
FT_ULong length = 0;
FT_Error error;
/* Note: FreeType like HarfBuzz uses the NONE tag for fetching the entire blob */
error = FT_Load_Sfnt_Table (ft_face, tag, 0, nullptr, &length);
if (error)
return nullptr;
buffer = (FT_Byte *) hb_malloc (length);
if (!buffer)
return nullptr;
error = FT_Load_Sfnt_Table (ft_face, tag, 0, buffer, &length);
if (error)
{
hb_free (buffer);
return nullptr;
}
return hb_blob_create ((const char *) buffer, length,
HB_MEMORY_MODE_WRITABLE,
buffer, hb_free);
}
/**
* hb_ft_face_create:
* @ft_face: (destroy destroy) (scope notified): FT_Face to work upon
* @destroy: (nullable): A callback to call when the face object is not needed anymore
*
* Creates an #hb_face_t face object from the specified FT_Face.
*
* This variant of the function does not provide any life-cycle management.
*
* Most client programs should use hb_ft_face_create_referenced()
* (or, perhaps, hb_ft_face_create_cached()) instead.
*
* If you know you have valid reasons not to use hb_ft_face_create_referenced(),
* then it is the client program's responsibility to destroy @ft_face
* after the #hb_face_t face object has been destroyed.
*
* Return value: (transfer full): the new #hb_face_t face object
*
* Since: 0.9.2
**/
hb_face_t *
hb_ft_face_create (FT_Face ft_face,
hb_destroy_func_t destroy)
{
hb_face_t *face;
if (!ft_face->stream->read) {
hb_blob_t *blob;
blob = hb_blob_create ((const char *) ft_face->stream->base,
(unsigned int) ft_face->stream->size,
HB_MEMORY_MODE_READONLY,
ft_face, destroy);
face = hb_face_create (blob, ft_face->face_index);
hb_blob_destroy (blob);
} else {
face = hb_face_create_for_tables (_hb_ft_reference_table, ft_face, destroy);
}
hb_face_set_index (face, ft_face->face_index);
hb_face_set_upem (face, ft_face->units_per_EM);
return face;
}
/**
* hb_ft_face_create_referenced:
* @ft_face: FT_Face to work upon
*
* Creates an #hb_face_t face object from the specified FT_Face.
*
* This is the preferred variant of the hb_ft_face_create*
* function family, because it calls FT_Reference_Face() on @ft_face,
* ensuring that @ft_face remains alive as long as the resulting
* #hb_face_t face object remains alive. Also calls FT_Done_Face()
* when the #hb_face_t face object is destroyed.
*
* Use this version unless you know you have good reasons not to.
*
* Return value: (transfer full): the new #hb_face_t face object
*
* Since: 0.9.38
**/
hb_face_t *
hb_ft_face_create_referenced (FT_Face ft_face)
{
FT_Reference_Face (ft_face);
return hb_ft_face_create (ft_face, _hb_ft_face_destroy);
}
static void
hb_ft_face_finalize (FT_Face ft_face)
{
hb_face_destroy ((hb_face_t *) ft_face->generic.data);
}
/**
* hb_ft_face_create_cached:
* @ft_face: FT_Face to work upon
*
* Creates an #hb_face_t face object from the specified FT_Face.
*
* This variant of the function caches the newly created #hb_face_t
* face object, using the @generic pointer of @ft_face. Subsequent function
* calls that are passed the same @ft_face parameter will have the same
* #hb_face_t returned to them, and that #hb_face_t will be correctly
* reference counted.
*
* However, client programs are still responsible for destroying
* @ft_face after the last #hb_face_t face object has been destroyed.
*
* Return value: (transfer full): the new #hb_face_t face object
*
* Since: 0.9.2
**/
hb_face_t *
hb_ft_face_create_cached (FT_Face ft_face)
{
if (unlikely (!ft_face->generic.data || ft_face->generic.finalizer != (FT_Generic_Finalizer) hb_ft_face_finalize))
{
if (ft_face->generic.finalizer)
ft_face->generic.finalizer (ft_face);
ft_face->generic.data = hb_ft_face_create (ft_face, nullptr);
ft_face->generic.finalizer = (FT_Generic_Finalizer) hb_ft_face_finalize;
}
return hb_face_reference ((hb_face_t *) ft_face->generic.data);
}
/**
* hb_ft_font_create:
* @ft_face: (destroy destroy) (scope notified): FT_Face to work upon
* @destroy: (nullable): A callback to call when the font object is not needed anymore
*
* Creates an #hb_font_t font object from the specified FT_Face.
*
* <note>Note: You must set the face size on @ft_face before calling
* hb_ft_font_create() on it. HarfBuzz assumes size is always set and will
* access `size` member of FT_Face unconditionally.</note>
*
* This variant of the function does not provide any life-cycle management.
*
* Most client programs should use hb_ft_font_create_referenced()
* instead.
*
* If you know you have valid reasons not to use hb_ft_font_create_referenced(),
* then it is the client program's responsibility to destroy @ft_face
* after the #hb_font_t font object has been destroyed.
*
* HarfBuzz will use the @destroy callback on the #hb_font_t font object
* if it is supplied when you use this function. However, even if @destroy
* is provided, it is the client program's responsibility to destroy @ft_face,
* and it is the client program's responsibility to ensure that @ft_face is
* destroyed only after the #hb_font_t font object has been destroyed.
*
* Return value: (transfer full): the new #hb_font_t font object
*
* Since: 0.9.2
**/
hb_font_t *
hb_ft_font_create (FT_Face ft_face,
hb_destroy_func_t destroy)
{
hb_font_t *font;
hb_face_t *face;
face = hb_ft_face_create (ft_face, destroy);
font = hb_font_create (face);
hb_face_destroy (face);
_hb_ft_font_set_funcs (font, ft_face, false);
hb_ft_font_changed (font);
return font;
}
/**
* hb_ft_font_changed:
* @font: #hb_font_t to work upon
*
* Refreshes the state of @font when the underlying FT_Face has changed.
* This function should be called after changing the size or
* variation-axis settings on the FT_Face.
*
* Since: 1.0.5
**/
void
hb_ft_font_changed (hb_font_t *font)
{
if (font->destroy != (hb_destroy_func_t) _hb_ft_font_destroy)
return;
hb_ft_font_t *ft_font = (hb_ft_font_t *) font->user_data;
FT_Face ft_face = ft_font->ft_face;
hb_font_set_scale (font,
(int) (((uint64_t) ft_face->size->metrics.x_scale * (uint64_t) ft_face->units_per_EM + (1u<<15)) >> 16),
(int) (((uint64_t) ft_face->size->metrics.y_scale * (uint64_t) ft_face->units_per_EM + (1u<<15)) >> 16));
#if 0 /* hb-ft works in no-hinting model */
hb_font_set_ppem (font,
ft_face->size->metrics.x_ppem,
ft_face->size->metrics.y_ppem);
#endif
#if defined(HAVE_FT_GET_VAR_BLEND_COORDINATES) && !defined(HB_NO_VAR)
FT_MM_Var *mm_var = nullptr;
if (!FT_Get_MM_Var (ft_face, &mm_var))
{
FT_Fixed *ft_coords = (FT_Fixed *) hb_calloc (mm_var->num_axis, sizeof (FT_Fixed));
int *coords = (int *) hb_calloc (mm_var->num_axis, sizeof (int));
if (coords && ft_coords)
{
if (!FT_Get_Var_Blend_Coordinates (ft_face, mm_var->num_axis, ft_coords))
{
bool nonzero = false;
for (unsigned int i = 0; i < mm_var->num_axis; ++i)
{
coords[i] = ft_coords[i] >>= 2;
nonzero = nonzero || coords[i];
}
if (nonzero)
hb_font_set_var_coords_normalized (font, coords, mm_var->num_axis);
else
hb_font_set_var_coords_normalized (font, nullptr, 0);
}
}
hb_free (coords);
hb_free (ft_coords);
#ifdef HAVE_FT_DONE_MM_VAR
FT_Done_MM_Var (ft_face->glyph->library, mm_var);
#else
hb_free (mm_var);
#endif
}
#endif
}
/**
* hb_ft_font_create_referenced:
* @ft_face: FT_Face to work upon
*
* Creates an #hb_font_t font object from the specified FT_Face.
*
* <note>Note: You must set the face size on @ft_face before calling
* hb_ft_font_create_referenced() on it. HarfBuzz assumes size is always set
* and will access `size` member of FT_Face unconditionally.</note>
*
* This is the preferred variant of the hb_ft_font_create*
* function family, because it calls FT_Reference_Face() on @ft_face,
* ensuring that @ft_face remains alive as long as the resulting
* #hb_font_t font object remains alive.
*
* Use this version unless you know you have good reasons not to.
*
* Return value: (transfer full): the new #hb_font_t font object
*
* Since: 0.9.38
**/
hb_font_t *
hb_ft_font_create_referenced (FT_Face ft_face)
{
FT_Reference_Face (ft_face);
return hb_ft_font_create (ft_face, _hb_ft_face_destroy);
}
static inline void free_static_ft_library ();
static struct hb_ft_library_lazy_loader_t : hb_lazy_loader_t<hb_remove_pointer<FT_Library>,
hb_ft_library_lazy_loader_t>
{
static FT_Library create ()
{
FT_Library l;
if (FT_Init_FreeType (&l))
return nullptr;
hb_atexit (free_static_ft_library);
return l;
}
static void destroy (FT_Library l)
{
FT_Done_FreeType (l);
}
static FT_Library get_null ()
{
return nullptr;
}
} static_ft_library;
static inline
void free_static_ft_library ()
{
static_ft_library.free_instance ();
}
static FT_Library
get_ft_library ()
{
return static_ft_library.get_unconst ();
}
static void
_release_blob (FT_Face ft_face)
{
hb_blob_destroy ((hb_blob_t *) ft_face->generic.data);
}
/**
* hb_ft_font_set_funcs:
* @font: #hb_font_t to work upon
*
* Configures the font-functions structure of the specified
* #hb_font_t font object to use FreeType font functions.
*
* In particular, you can use this function to configure an
* existing #hb_face_t face object for use with FreeType font
* functions even if that #hb_face_t face object was initially
* created with hb_face_create(), and therefore was not
* initially configured to use FreeType font functions.
*
* An #hb_face_t face object created with hb_ft_face_create()
* is preconfigured for FreeType font functions and does not
* require this function to be used.
*
* <note>Note: Internally, this function creates an FT_Face.
* </note>
*
* Since: 1.0.5
**/
void
hb_ft_font_set_funcs (hb_font_t *font)
{
hb_blob_t *blob = hb_face_reference_blob (font->face);
unsigned int blob_length;
const char *blob_data = hb_blob_get_data (blob, &blob_length);
if (unlikely (!blob_length))
DEBUG_MSG (FT, font, "Font face has empty blob");
FT_Face ft_face = nullptr;
FT_Error err = FT_New_Memory_Face (get_ft_library (),
(const FT_Byte *) blob_data,
blob_length,
hb_face_get_index (font->face),
&ft_face);
if (unlikely (err)) {
hb_blob_destroy (blob);
DEBUG_MSG (FT, font, "Font face FT_New_Memory_Face() failed");
return;
}
if (FT_Select_Charmap (ft_face, FT_ENCODING_MS_SYMBOL))
FT_Select_Charmap (ft_face, FT_ENCODING_UNICODE);
FT_Set_Char_Size (ft_face,
abs (font->x_scale), abs (font->y_scale),
0, 0);
#if 0
font->x_ppem * 72 * 64 / font->x_scale,
font->y_ppem * 72 * 64 / font->y_scale);
#endif
if (font->x_scale < 0 || font->y_scale < 0)
{
FT_Matrix matrix = { font->x_scale < 0 ? -1 : +1, 0,
0, font->y_scale < 0 ? -1 : +1};
FT_Set_Transform (ft_face, &matrix, nullptr);
}
#if defined(HAVE_FT_GET_VAR_BLEND_COORDINATES) && !defined(HB_NO_VAR)
unsigned int num_coords;
const int *coords = hb_font_get_var_coords_normalized (font, &num_coords);
if (num_coords)
{
FT_Fixed *ft_coords = (FT_Fixed *) hb_calloc (num_coords, sizeof (FT_Fixed));
if (ft_coords)
{
for (unsigned int i = 0; i < num_coords; i++)
ft_coords[i] = coords[i] * 4;
FT_Set_Var_Blend_Coordinates (ft_face, num_coords, ft_coords);
hb_free (ft_coords);
}
}
#endif
ft_face->generic.data = blob;
ft_face->generic.finalizer = (FT_Generic_Finalizer) _release_blob;
_hb_ft_font_set_funcs (font, ft_face, true);
hb_ft_font_set_load_flags (font, FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING);
}
#endif