harfbuzz/src/hb-font.hh

721 lines
21 KiB
C++

/*
* Copyright © 2009 Red Hat, Inc.
* Copyright © 2011 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
*/
#ifndef HB_FONT_HH
#define HB_FONT_HH
#include "hb.hh"
#include "hb-face.hh"
#include "hb-shaper.hh"
/*
* hb_font_funcs_t
*/
#define HB_FONT_FUNCS_IMPLEMENT_CALLBACKS \
HB_FONT_FUNC_IMPLEMENT (get_,font_h_extents) \
HB_FONT_FUNC_IMPLEMENT (get_,font_v_extents) \
HB_FONT_FUNC_IMPLEMENT (get_,nominal_glyph) \
HB_FONT_FUNC_IMPLEMENT (get_,nominal_glyphs) \
HB_FONT_FUNC_IMPLEMENT (get_,variation_glyph) \
HB_FONT_FUNC_IMPLEMENT (get_,glyph_h_advance) \
HB_FONT_FUNC_IMPLEMENT (get_,glyph_v_advance) \
HB_FONT_FUNC_IMPLEMENT (get_,glyph_h_advances) \
HB_FONT_FUNC_IMPLEMENT (get_,glyph_v_advances) \
HB_FONT_FUNC_IMPLEMENT (get_,glyph_h_origin) \
HB_FONT_FUNC_IMPLEMENT (get_,glyph_v_origin) \
HB_FONT_FUNC_IMPLEMENT (get_,glyph_h_kerning) \
HB_IF_NOT_DEPRECATED (HB_FONT_FUNC_IMPLEMENT (get_,glyph_v_kerning)) \
HB_FONT_FUNC_IMPLEMENT (get_,glyph_extents) \
HB_FONT_FUNC_IMPLEMENT (get_,glyph_contour_point) \
HB_FONT_FUNC_IMPLEMENT (get_,glyph_name) \
HB_FONT_FUNC_IMPLEMENT (get_,glyph_from_name) \
HB_FONT_FUNC_IMPLEMENT (,draw_glyph) \
HB_FONT_FUNC_IMPLEMENT (,paint_glyph) \
/* ^--- Add new callbacks here */
struct hb_font_funcs_t
{
hb_object_header_t header;
struct {
#define HB_FONT_FUNC_IMPLEMENT(get_,name) void *name;
HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
#undef HB_FONT_FUNC_IMPLEMENT
} *user_data;
struct {
#define HB_FONT_FUNC_IMPLEMENT(get_,name) hb_destroy_func_t name;
HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
#undef HB_FONT_FUNC_IMPLEMENT
} *destroy;
/* Don't access these directly. Call font->get_*() instead. */
union get_t {
struct get_funcs_t {
#define HB_FONT_FUNC_IMPLEMENT(get_,name) hb_font_##get_##name##_func_t name;
HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
#undef HB_FONT_FUNC_IMPLEMENT
} f;
void (*array[0
#define HB_FONT_FUNC_IMPLEMENT(get_,name) +1
HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
#undef HB_FONT_FUNC_IMPLEMENT
]) ();
} get;
};
DECLARE_NULL_INSTANCE (hb_font_funcs_t);
/*
* hb_font_t
*/
#define HB_SHAPER_IMPLEMENT(shaper) HB_SHAPER_DATA_INSTANTIATE_SHAPERS(shaper, font);
#include "hb-shaper-list.hh"
#undef HB_SHAPER_IMPLEMENT
struct hb_font_t
{
hb_object_header_t header;
unsigned int serial;
unsigned int serial_coords;
hb_font_t *parent;
hb_face_t *face;
int32_t x_scale;
int32_t y_scale;
float x_embolden;
float y_embolden;
bool embolden_in_place;
int32_t x_strength; /* x_embolden, in scaled units. */
int32_t y_strength; /* y_embolden, in scaled units. */
float slant;
float slant_xy;
float x_multf;
float y_multf;
int64_t x_mult;
int64_t y_mult;
unsigned int x_ppem;
unsigned int y_ppem;
float ptem;
/* Font variation coordinates. */
unsigned int instance_index;
unsigned int num_coords;
int *coords;
float *design_coords;
hb_font_funcs_t *klass;
void *user_data;
hb_destroy_func_t destroy;
hb_shaper_object_dataset_t<hb_font_t> data; /* Various shaper data. */
/* Convert from font-space to user-space */
int64_t dir_mult (hb_direction_t direction)
{ return HB_DIRECTION_IS_VERTICAL(direction) ? y_mult : x_mult; }
hb_position_t em_scale_x (int16_t v) { return em_mult (v, x_mult); }
hb_position_t em_scale_y (int16_t v) { return em_mult (v, y_mult); }
hb_position_t em_scalef_x (float v) { return em_multf (v, x_multf); }
hb_position_t em_scalef_y (float v) { return em_multf (v, y_multf); }
float em_fscale_x (int16_t v) { return em_fmult (v, x_multf); }
float em_fscale_y (int16_t v) { return em_fmult (v, y_multf); }
float em_fscalef_x (float v) { return em_fmultf (v, x_multf); }
float em_fscalef_y (float v) { return em_fmultf (v, y_multf); }
hb_position_t em_scale_dir (int16_t v, hb_direction_t direction)
{ return em_mult (v, dir_mult (direction)); }
/* Convert from parent-font user-space to our user-space */
hb_position_t parent_scale_x_distance (hb_position_t v)
{
if (unlikely (parent && parent->x_scale != x_scale))
return (hb_position_t) (v * (int64_t) this->x_scale / this->parent->x_scale);
return v;
}
hb_position_t parent_scale_y_distance (hb_position_t v)
{
if (unlikely (parent && parent->y_scale != y_scale))
return (hb_position_t) (v * (int64_t) this->y_scale / this->parent->y_scale);
return v;
}
hb_position_t parent_scale_x_position (hb_position_t v)
{ return parent_scale_x_distance (v); }
hb_position_t parent_scale_y_position (hb_position_t v)
{ return parent_scale_y_distance (v); }
void parent_scale_distance (hb_position_t *x, hb_position_t *y)
{
*x = parent_scale_x_distance (*x);
*y = parent_scale_y_distance (*y);
}
void parent_scale_position (hb_position_t *x, hb_position_t *y)
{
*x = parent_scale_x_position (*x);
*y = parent_scale_y_position (*y);
}
void scale_glyph_extents (hb_glyph_extents_t *extents)
{
float x1 = em_fscale_x (extents->x_bearing);
float y1 = em_fscale_y (extents->y_bearing);
float x2 = em_fscale_x (extents->x_bearing + extents->width);
float y2 = em_fscale_y (extents->y_bearing + extents->height);
/* Apply slant. */
if (slant_xy)
{
x1 += hb_min (y1 * slant_xy, y2 * slant_xy);
x2 += hb_max (y1 * slant_xy, y2 * slant_xy);
}
extents->x_bearing = floorf (x1);
extents->y_bearing = floorf (y1);
extents->width = ceilf (x2) - extents->x_bearing;
extents->height = ceilf (y2) - extents->y_bearing;
if (x_strength || y_strength)
{
/* Y */
int y_shift = y_strength;
if (y_scale < 0) y_shift = -y_shift;
extents->y_bearing += y_shift;
extents->height -= y_shift;
/* X */
int x_shift = x_strength;
if (x_scale < 0) x_shift = -x_shift;
if (embolden_in_place)
extents->x_bearing -= x_shift / 2;
extents->width += x_shift;
}
}
/* Public getters */
HB_INTERNAL bool has_func (unsigned int i);
HB_INTERNAL bool has_func_set (unsigned int i);
/* has_* ... */
#define HB_FONT_FUNC_IMPLEMENT(get_,name) \
bool \
has_##name##_func () \
{ \
hb_font_funcs_t *funcs = this->klass; \
unsigned int i = offsetof (hb_font_funcs_t::get_t::get_funcs_t, name) / sizeof (funcs->get.array[0]); \
return has_func (i); \
} \
bool \
has_##name##_func_set () \
{ \
hb_font_funcs_t *funcs = this->klass; \
unsigned int i = offsetof (hb_font_funcs_t::get_t::get_funcs_t, name) / sizeof (funcs->get.array[0]); \
return has_func_set (i); \
}
HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
#undef HB_FONT_FUNC_IMPLEMENT
hb_bool_t get_font_h_extents (hb_font_extents_t *extents)
{
hb_memset (extents, 0, sizeof (*extents));
return klass->get.f.font_h_extents (this, user_data,
extents,
!klass->user_data ? nullptr : klass->user_data->font_h_extents);
}
hb_bool_t get_font_v_extents (hb_font_extents_t *extents)
{
hb_memset (extents, 0, sizeof (*extents));
return klass->get.f.font_v_extents (this, user_data,
extents,
!klass->user_data ? nullptr : klass->user_data->font_v_extents);
}
bool has_glyph (hb_codepoint_t unicode)
{
hb_codepoint_t glyph;
return get_nominal_glyph (unicode, &glyph);
}
hb_bool_t get_nominal_glyph (hb_codepoint_t unicode,
hb_codepoint_t *glyph,
hb_codepoint_t not_found = 0)
{
*glyph = not_found;
return klass->get.f.nominal_glyph (this, user_data,
unicode, glyph,
!klass->user_data ? nullptr : klass->user_data->nominal_glyph);
}
unsigned int get_nominal_glyphs (unsigned int count,
const hb_codepoint_t *first_unicode,
unsigned int unicode_stride,
hb_codepoint_t *first_glyph,
unsigned int glyph_stride)
{
return klass->get.f.nominal_glyphs (this, user_data,
count,
first_unicode, unicode_stride,
first_glyph, glyph_stride,
!klass->user_data ? nullptr : klass->user_data->nominal_glyphs);
}
hb_bool_t get_variation_glyph (hb_codepoint_t unicode, hb_codepoint_t variation_selector,
hb_codepoint_t *glyph,
hb_codepoint_t not_found = 0)
{
*glyph = not_found;
return klass->get.f.variation_glyph (this, user_data,
unicode, variation_selector, glyph,
!klass->user_data ? nullptr : klass->user_data->variation_glyph);
}
hb_position_t get_glyph_h_advance (hb_codepoint_t glyph)
{
return klass->get.f.glyph_h_advance (this, user_data,
glyph,
!klass->user_data ? nullptr : klass->user_data->glyph_h_advance);
}
hb_position_t get_glyph_v_advance (hb_codepoint_t glyph)
{
return klass->get.f.glyph_v_advance (this, user_data,
glyph,
!klass->user_data ? nullptr : klass->user_data->glyph_v_advance);
}
void get_glyph_h_advances (unsigned int count,
const hb_codepoint_t *first_glyph,
unsigned int glyph_stride,
hb_position_t *first_advance,
unsigned int advance_stride)
{
return klass->get.f.glyph_h_advances (this, user_data,
count,
first_glyph, glyph_stride,
first_advance, advance_stride,
!klass->user_data ? nullptr : klass->user_data->glyph_h_advances);
}
void get_glyph_v_advances (unsigned int count,
const hb_codepoint_t *first_glyph,
unsigned int glyph_stride,
hb_position_t *first_advance,
unsigned int advance_stride)
{
return klass->get.f.glyph_v_advances (this, user_data,
count,
first_glyph, glyph_stride,
first_advance, advance_stride,
!klass->user_data ? nullptr : klass->user_data->glyph_v_advances);
}
hb_bool_t get_glyph_h_origin (hb_codepoint_t glyph,
hb_position_t *x, hb_position_t *y)
{
*x = *y = 0;
return klass->get.f.glyph_h_origin (this, user_data,
glyph, x, y,
!klass->user_data ? nullptr : klass->user_data->glyph_h_origin);
}
hb_bool_t get_glyph_v_origin (hb_codepoint_t glyph,
hb_position_t *x, hb_position_t *y)
{
*x = *y = 0;
return klass->get.f.glyph_v_origin (this, user_data,
glyph, x, y,
!klass->user_data ? nullptr : klass->user_data->glyph_v_origin);
}
hb_position_t get_glyph_h_kerning (hb_codepoint_t left_glyph,
hb_codepoint_t right_glyph)
{
#ifdef HB_DISABLE_DEPRECATED
return 0;
#else
return klass->get.f.glyph_h_kerning (this, user_data,
left_glyph, right_glyph,
!klass->user_data ? nullptr : klass->user_data->glyph_h_kerning);
#endif
}
hb_position_t get_glyph_v_kerning (hb_codepoint_t top_glyph,
hb_codepoint_t bottom_glyph)
{
#ifdef HB_DISABLE_DEPRECATED
return 0;
#else
return klass->get.f.glyph_v_kerning (this, user_data,
top_glyph, bottom_glyph,
!klass->user_data ? nullptr : klass->user_data->glyph_v_kerning);
#endif
}
hb_bool_t get_glyph_extents (hb_codepoint_t glyph,
hb_glyph_extents_t *extents)
{
hb_memset (extents, 0, sizeof (*extents));
return klass->get.f.glyph_extents (this, user_data,
glyph,
extents,
!klass->user_data ? nullptr : klass->user_data->glyph_extents);
}
hb_bool_t get_glyph_contour_point (hb_codepoint_t glyph, unsigned int point_index,
hb_position_t *x, hb_position_t *y)
{
*x = *y = 0;
return klass->get.f.glyph_contour_point (this, user_data,
glyph, point_index,
x, y,
!klass->user_data ? nullptr : klass->user_data->glyph_contour_point);
}
hb_bool_t get_glyph_name (hb_codepoint_t glyph,
char *name, unsigned int size)
{
if (size) *name = '\0';
return klass->get.f.glyph_name (this, user_data,
glyph,
name, size,
!klass->user_data ? nullptr : klass->user_data->glyph_name);
}
hb_bool_t get_glyph_from_name (const char *name, int len, /* -1 means nul-terminated */
hb_codepoint_t *glyph)
{
*glyph = 0;
if (len == -1) len = strlen (name);
return klass->get.f.glyph_from_name (this, user_data,
name, len,
glyph,
!klass->user_data ? nullptr : klass->user_data->glyph_from_name);
}
void draw_glyph (hb_codepoint_t glyph,
hb_draw_funcs_t *draw_funcs, void *draw_data)
{
klass->get.f.draw_glyph (this, user_data,
glyph,
draw_funcs, draw_data,
!klass->user_data ? nullptr : klass->user_data->draw_glyph);
}
void paint_glyph (hb_codepoint_t glyph,
hb_paint_funcs_t *paint_funcs, void *paint_data,
unsigned int palette,
hb_color_t foreground)
{
klass->get.f.paint_glyph (this, user_data,
glyph,
paint_funcs, paint_data,
palette, foreground,
!klass->user_data ? nullptr : klass->user_data->paint_glyph);
}
/* A bit higher-level, and with fallback */
void get_h_extents_with_fallback (hb_font_extents_t *extents)
{
if (!get_font_h_extents (extents))
{
extents->ascender = y_scale * .8;
extents->descender = extents->ascender - y_scale;
extents->line_gap = 0;
}
}
void get_v_extents_with_fallback (hb_font_extents_t *extents)
{
if (!get_font_v_extents (extents))
{
extents->ascender = x_scale / 2;
extents->descender = extents->ascender - x_scale;
extents->line_gap = 0;
}
}
void get_extents_for_direction (hb_direction_t direction,
hb_font_extents_t *extents)
{
if (likely (HB_DIRECTION_IS_HORIZONTAL (direction)))
get_h_extents_with_fallback (extents);
else
get_v_extents_with_fallback (extents);
}
void get_glyph_advance_for_direction (hb_codepoint_t glyph,
hb_direction_t direction,
hb_position_t *x, hb_position_t *y)
{
*x = *y = 0;
if (likely (HB_DIRECTION_IS_HORIZONTAL (direction)))
*x = get_glyph_h_advance (glyph);
else
*y = get_glyph_v_advance (glyph);
}
void get_glyph_advances_for_direction (hb_direction_t direction,
unsigned int count,
const hb_codepoint_t *first_glyph,
unsigned glyph_stride,
hb_position_t *first_advance,
unsigned advance_stride)
{
if (likely (HB_DIRECTION_IS_HORIZONTAL (direction)))
get_glyph_h_advances (count, first_glyph, glyph_stride, first_advance, advance_stride);
else
get_glyph_v_advances (count, first_glyph, glyph_stride, first_advance, advance_stride);
}
void guess_v_origin_minus_h_origin (hb_codepoint_t glyph,
hb_position_t *x, hb_position_t *y)
{
*x = get_glyph_h_advance (glyph) / 2;
hb_font_extents_t extents;
get_h_extents_with_fallback (&extents);
*y = extents.ascender;
}
void get_glyph_h_origin_with_fallback (hb_codepoint_t glyph,
hb_position_t *x, hb_position_t *y)
{
if (!get_glyph_h_origin (glyph, x, y) &&
get_glyph_v_origin (glyph, x, y))
{
hb_position_t dx, dy;
guess_v_origin_minus_h_origin (glyph, &dx, &dy);
*x -= dx; *y -= dy;
}
}
void get_glyph_v_origin_with_fallback (hb_codepoint_t glyph,
hb_position_t *x, hb_position_t *y)
{
if (!get_glyph_v_origin (glyph, x, y) &&
get_glyph_h_origin (glyph, x, y))
{
hb_position_t dx, dy;
guess_v_origin_minus_h_origin (glyph, &dx, &dy);
*x += dx; *y += dy;
}
}
void get_glyph_origin_for_direction (hb_codepoint_t glyph,
hb_direction_t direction,
hb_position_t *x, hb_position_t *y)
{
if (likely (HB_DIRECTION_IS_HORIZONTAL (direction)))
get_glyph_h_origin_with_fallback (glyph, x, y);
else
get_glyph_v_origin_with_fallback (glyph, x, y);
}
void add_glyph_h_origin (hb_codepoint_t glyph,
hb_position_t *x, hb_position_t *y)
{
hb_position_t origin_x, origin_y;
get_glyph_h_origin_with_fallback (glyph, &origin_x, &origin_y);
*x += origin_x;
*y += origin_y;
}
void add_glyph_v_origin (hb_codepoint_t glyph,
hb_position_t *x, hb_position_t *y)
{
hb_position_t origin_x, origin_y;
get_glyph_v_origin_with_fallback (glyph, &origin_x, &origin_y);
*x += origin_x;
*y += origin_y;
}
void add_glyph_origin_for_direction (hb_codepoint_t glyph,
hb_direction_t direction,
hb_position_t *x, hb_position_t *y)
{
hb_position_t origin_x, origin_y;
get_glyph_origin_for_direction (glyph, direction, &origin_x, &origin_y);
*x += origin_x;
*y += origin_y;
}
void subtract_glyph_h_origin (hb_codepoint_t glyph,
hb_position_t *x, hb_position_t *y)
{
hb_position_t origin_x, origin_y;
get_glyph_h_origin_with_fallback (glyph, &origin_x, &origin_y);
*x -= origin_x;
*y -= origin_y;
}
void subtract_glyph_v_origin (hb_codepoint_t glyph,
hb_position_t *x, hb_position_t *y)
{
hb_position_t origin_x, origin_y;
get_glyph_v_origin_with_fallback (glyph, &origin_x, &origin_y);
*x -= origin_x;
*y -= origin_y;
}
void subtract_glyph_origin_for_direction (hb_codepoint_t glyph,
hb_direction_t direction,
hb_position_t *x, hb_position_t *y)
{
hb_position_t origin_x, origin_y;
get_glyph_origin_for_direction (glyph, direction, &origin_x, &origin_y);
*x -= origin_x;
*y -= origin_y;
}
void get_glyph_kerning_for_direction (hb_codepoint_t first_glyph, hb_codepoint_t second_glyph,
hb_direction_t direction,
hb_position_t *x, hb_position_t *y)
{
if (likely (HB_DIRECTION_IS_HORIZONTAL (direction))) {
*y = 0;
*x = get_glyph_h_kerning (first_glyph, second_glyph);
} else {
*x = 0;
*y = get_glyph_v_kerning (first_glyph, second_glyph);
}
}
hb_bool_t get_glyph_extents_for_origin (hb_codepoint_t glyph,
hb_direction_t direction,
hb_glyph_extents_t *extents)
{
hb_bool_t ret = get_glyph_extents (glyph, extents);
if (ret)
subtract_glyph_origin_for_direction (glyph, direction, &extents->x_bearing, &extents->y_bearing);
return ret;
}
hb_bool_t get_glyph_contour_point_for_origin (hb_codepoint_t glyph, unsigned int point_index,
hb_direction_t direction,
hb_position_t *x, hb_position_t *y)
{
hb_bool_t ret = get_glyph_contour_point (glyph, point_index, x, y);
if (ret)
subtract_glyph_origin_for_direction (glyph, direction, x, y);
return ret;
}
/* Generates gidDDD if glyph has no name. */
void
glyph_to_string (hb_codepoint_t glyph,
char *s, unsigned int size)
{
if (get_glyph_name (glyph, s, size)) return;
if (size && snprintf (s, size, "gid%u", glyph) < 0)
*s = '\0';
}
/* Parses gidDDD and uniUUUU strings automatically. */
hb_bool_t
glyph_from_string (const char *s, int len, /* -1 means nul-terminated */
hb_codepoint_t *glyph)
{
if (get_glyph_from_name (s, len, glyph)) return true;
if (len == -1) len = strlen (s);
/* Straight glyph index. */
if (hb_codepoint_parse (s, len, 10, glyph))
return true;
if (len > 3)
{
/* gidDDD syntax for glyph indices. */
if (0 == strncmp (s, "gid", 3) &&
hb_codepoint_parse (s + 3, len - 3, 10, glyph))
return true;
/* uniUUUU and other Unicode character indices. */
hb_codepoint_t unichar;
if (0 == strncmp (s, "uni", 3) &&
hb_codepoint_parse (s + 3, len - 3, 16, &unichar) &&
get_nominal_glyph (unichar, glyph))
return true;
}
return false;
}
void mults_changed ()
{
float upem = face->get_upem ();
x_multf = x_scale / upem;
y_multf = y_scale / upem;
bool x_neg = x_scale < 0;
x_mult = (x_neg ? -((int64_t) -x_scale << 16) : ((int64_t) x_scale << 16)) / upem;
bool y_neg = y_scale < 0;
y_mult = (y_neg ? -((int64_t) -y_scale << 16) : ((int64_t) y_scale << 16)) / upem;
x_strength = fabsf (roundf (x_scale * x_embolden));
y_strength = fabsf (roundf (y_scale * y_embolden));
slant_xy = y_scale ? slant * x_scale / y_scale : 0.f;
data.fini ();
}
hb_position_t em_mult (int16_t v, int64_t mult)
{ return (hb_position_t) ((v * mult + 32768) >> 16); }
hb_position_t em_multf (float v, float mult)
{ return (hb_position_t) roundf (em_fmultf (v, mult)); }
float em_fmultf (float v, float mult)
{ return v * mult; }
float em_fmult (int16_t v, float mult)
{ return (float) v * mult; }
};
DECLARE_NULL_INSTANCE (hb_font_t);
#endif /* HB_FONT_HH */