harfbuzz/src/hb-font-private.hh
2012-11-15 16:23:21 -08:00

470 lines
13 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_PRIVATE_HH
#define HB_FONT_PRIVATE_HH
#include "hb-private.hh"
#include "hb-font.h"
#include "hb-object-private.hh"
#include "hb-shaper-private.hh"
#include "hb-shape-plan-private.hh"
/*
* hb_font_funcs_t
*/
#define HB_FONT_FUNCS_IMPLEMENT_CALLBACKS \
HB_FONT_FUNC_IMPLEMENT (glyph) \
HB_FONT_FUNC_IMPLEMENT (glyph_h_advance) \
HB_FONT_FUNC_IMPLEMENT (glyph_v_advance) \
HB_FONT_FUNC_IMPLEMENT (glyph_h_origin) \
HB_FONT_FUNC_IMPLEMENT (glyph_v_origin) \
HB_FONT_FUNC_IMPLEMENT (glyph_h_kerning) \
HB_FONT_FUNC_IMPLEMENT (glyph_v_kerning) \
HB_FONT_FUNC_IMPLEMENT (glyph_extents) \
HB_FONT_FUNC_IMPLEMENT (glyph_contour_point) \
HB_FONT_FUNC_IMPLEMENT (glyph_name) \
HB_FONT_FUNC_IMPLEMENT (glyph_from_name) \
/* ^--- Add new callbacks here */
struct hb_font_funcs_t {
hb_object_header_t header;
ASSERT_POD ();
hb_bool_t immutable;
/* Don't access these directly. Call hb_font_get_*() instead. */
struct {
#define HB_FONT_FUNC_IMPLEMENT(name) hb_font_get_##name##_func_t name;
HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
#undef HB_FONT_FUNC_IMPLEMENT
} get;
struct {
#define HB_FONT_FUNC_IMPLEMENT(name) void *name;
HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
#undef HB_FONT_FUNC_IMPLEMENT
} user_data;
struct {
#define HB_FONT_FUNC_IMPLEMENT(name) hb_destroy_func_t name;
HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
#undef HB_FONT_FUNC_IMPLEMENT
} destroy;
};
/*
* hb_face_t
*/
struct hb_face_t {
hb_object_header_t header;
ASSERT_POD ();
hb_bool_t immutable;
hb_reference_table_func_t reference_table_func;
void *user_data;
hb_destroy_func_t destroy;
unsigned int index;
mutable unsigned int upem;
mutable unsigned int num_glyphs;
struct hb_shaper_data_t shaper_data;
struct plan_node_t {
hb_shape_plan_t *shape_plan;
plan_node_t *next;
} *shape_plans;
inline hb_blob_t *reference_table (hb_tag_t tag) const
{
hb_blob_t *blob;
if (unlikely (!this || !reference_table_func))
return hb_blob_get_empty ();
blob = reference_table_func (/*XXX*/const_cast<hb_face_t *> (this), tag, user_data);
if (unlikely (!blob))
return hb_blob_get_empty ();
return blob;
}
inline unsigned int get_upem (void) const
{
if (unlikely (!upem))
load_upem ();
return upem;
}
inline unsigned int get_num_glyphs (void) const
{
if (unlikely (num_glyphs == (unsigned int) -1))
load_num_glyphs ();
return num_glyphs;
}
private:
HB_INTERNAL void load_upem (void) const;
HB_INTERNAL void load_num_glyphs (void) const;
};
#define HB_SHAPER_DATA_CREATE_FUNC_EXTRA_ARGS
#define HB_SHAPER_IMPLEMENT(shaper) HB_SHAPER_DATA_PROTOTYPE(shaper, face);
#include "hb-shaper-list.hh"
#undef HB_SHAPER_IMPLEMENT
#undef HB_SHAPER_DATA_CREATE_FUNC_EXTRA_ARGS
/*
* hb_font_t
*/
struct hb_font_t {
hb_object_header_t header;
ASSERT_POD ();
hb_bool_t immutable;
hb_font_t *parent;
hb_face_t *face;
int x_scale;
int y_scale;
unsigned int x_ppem;
unsigned int y_ppem;
hb_font_funcs_t *klass;
void *user_data;
hb_destroy_func_t destroy;
struct hb_shaper_data_t shaper_data;
/* Convert from font-space to user-space */
inline hb_position_t em_scale_x (int16_t v) { return em_scale (v, this->x_scale); }
inline hb_position_t em_scale_y (int16_t v) { return em_scale (v, this->y_scale); }
/* Convert from parent-font user-space to our user-space */
inline hb_position_t parent_scale_x_distance (hb_position_t v) {
if (unlikely (parent && parent->x_scale != x_scale))
return v * (int64_t) this->x_scale / this->parent->x_scale;
return v;
}
inline hb_position_t parent_scale_y_distance (hb_position_t v) {
if (unlikely (parent && parent->y_scale != y_scale))
return v * (int64_t) this->y_scale / this->parent->y_scale;
return v;
}
inline hb_position_t parent_scale_x_position (hb_position_t v) {
return parent_scale_x_distance (v);
}
inline hb_position_t parent_scale_y_position (hb_position_t v) {
return parent_scale_y_distance (v);
}
inline void parent_scale_distance (hb_position_t *x, hb_position_t *y) {
*x = parent_scale_x_distance (*x);
*y = parent_scale_y_distance (*y);
}
inline void parent_scale_position (hb_position_t *x, hb_position_t *y) {
*x = parent_scale_x_position (*x);
*y = parent_scale_y_position (*y);
}
/* Public getters */
inline hb_bool_t get_glyph (hb_codepoint_t unicode, hb_codepoint_t variation_selector,
hb_codepoint_t *glyph)
{
*glyph = 0;
return klass->get.glyph (this, user_data,
unicode, variation_selector, glyph,
klass->user_data.glyph);
}
inline hb_position_t get_glyph_h_advance (hb_codepoint_t glyph)
{
return klass->get.glyph_h_advance (this, user_data,
glyph,
klass->user_data.glyph_h_advance);
}
inline hb_position_t get_glyph_v_advance (hb_codepoint_t glyph)
{
return klass->get.glyph_v_advance (this, user_data,
glyph,
klass->user_data.glyph_v_advance);
}
inline 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.glyph_h_origin (this, user_data,
glyph, x, y,
klass->user_data.glyph_h_origin);
}
inline 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.glyph_v_origin (this, user_data,
glyph, x, y,
klass->user_data.glyph_v_origin);
}
inline hb_position_t get_glyph_h_kerning (hb_codepoint_t left_glyph, hb_codepoint_t right_glyph)
{
return klass->get.glyph_h_kerning (this, user_data,
left_glyph, right_glyph,
klass->user_data.glyph_h_kerning);
}
inline hb_position_t get_glyph_v_kerning (hb_codepoint_t left_glyph, hb_codepoint_t right_glyph)
{
return klass->get.glyph_v_kerning (this, user_data,
left_glyph, right_glyph,
klass->user_data.glyph_v_kerning);
}
inline hb_bool_t get_glyph_extents (hb_codepoint_t glyph,
hb_glyph_extents_t *extents)
{
memset (extents, 0, sizeof (*extents));
return klass->get.glyph_extents (this, user_data,
glyph,
extents,
klass->user_data.glyph_extents);
}
inline 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.glyph_contour_point (this, user_data,
glyph, point_index,
x, y,
klass->user_data.glyph_contour_point);
}
inline hb_bool_t get_glyph_name (hb_codepoint_t glyph,
char *name, unsigned int size)
{
if (size) *name = '\0';
return klass->get.glyph_name (this, user_data,
glyph,
name, size,
klass->user_data.glyph_name);
}
inline 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.glyph_from_name (this, user_data,
name, len,
glyph,
klass->user_data.glyph_from_name);
}
/* A bit higher-level, and with fallback */
inline void get_glyph_advance_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))) {
*x = get_glyph_h_advance (glyph);
*y = 0;
} else {
*x = 0;
*y = get_glyph_v_advance (glyph);
}
}
/* Internal only */
inline 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;
/* TODO use font_metics.ascent */
*y = y_scale;
}
inline 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))) {
hb_bool_t ret = get_glyph_h_origin (glyph, x, y);
if (!ret && (ret = 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;
}
} else {
hb_bool_t ret = get_glyph_v_origin (glyph, x, y);
if (!ret && (ret = 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;
}
}
}
inline 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;
}
inline 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;
}
inline 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))) {
*x = get_glyph_h_kerning (first_glyph, second_glyph);
*y = 0;
} else {
*x = 0;
*y = get_glyph_v_kerning (first_glyph, second_glyph);
}
}
inline 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;
}
inline 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. */
inline void
glyph_to_string (hb_codepoint_t glyph,
char *s, unsigned int size)
{
if (get_glyph_name (glyph, s, size)) return;
snprintf (s, size, "gid%u", glyph);
}
/* Parses gidDDD and uniUUUU strings automatically. */
inline 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_glyph (unichar, 0, glyph))
return true;
}
return false;
}
private:
inline hb_position_t em_scale (int16_t v, int scale) { return v * (int64_t) scale / hb_face_get_upem (this->face); }
};
#define HB_SHAPER_DATA_CREATE_FUNC_EXTRA_ARGS
#define HB_SHAPER_IMPLEMENT(shaper) HB_SHAPER_DATA_PROTOTYPE(shaper, font);
#include "hb-shaper-list.hh"
#undef HB_SHAPER_IMPLEMENT
#undef HB_SHAPER_DATA_CREATE_FUNC_EXTRA_ARGS
#endif /* HB_FONT_PRIVATE_HH */