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/*
* Copyright © 2022 Red Hat, 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): Matthias Clasen
*/
#include "hb.hh"
#ifdef HAVE_CAIRO
#include "hb-cairo.h"
#include "hb-cairo-utils.hh"
#include "hb-machinery.hh"
#include "hb-utf.hh"
/**
* SECTION:hb-cairo
* @title: hb-cairo
* @short_description: Cairo integration
* @include: hb-cairo.h
*
* Functions for using HarfBuzz with the cairo library.
*
* HarfBuzz supports using cairo for rendering.
**/
static void
hb_cairo_move_to (hb_draw_funcs_t *dfuncs HB_UNUSED,
void *draw_data,
hb_draw_state_t *st HB_UNUSED,
float to_x, float to_y,
void *user_data HB_UNUSED)
{
cairo_t *cr = (cairo_t *) draw_data;
cairo_move_to (cr, (double) to_x, (double) to_y);
}
static void
hb_cairo_line_to (hb_draw_funcs_t *dfuncs HB_UNUSED,
void *draw_data,
hb_draw_state_t *st HB_UNUSED,
float to_x, float to_y,
void *user_data HB_UNUSED)
{
cairo_t *cr = (cairo_t *) draw_data;
cairo_line_to (cr, (double) to_x, (double) to_y);
}
static void
hb_cairo_cubic_to (hb_draw_funcs_t *dfuncs HB_UNUSED,
void *draw_data,
hb_draw_state_t *st HB_UNUSED,
float control1_x, float control1_y,
float control2_x, float control2_y,
float to_x, float to_y,
void *user_data HB_UNUSED)
{
cairo_t *cr = (cairo_t *) draw_data;
cairo_curve_to (cr,
(double) control1_x, (double) control1_y,
(double) control2_x, (double) control2_y,
(double) to_x, (double) to_y);
}
static void
hb_cairo_close_path (hb_draw_funcs_t *dfuncs HB_UNUSED,
void *draw_data,
hb_draw_state_t *st HB_UNUSED,
void *user_data HB_UNUSED)
{
cairo_t *cr = (cairo_t *) draw_data;
cairo_close_path (cr);
}
static inline void free_static_cairo_draw_funcs ();
static struct hb_cairo_draw_funcs_lazy_loader_t : hb_draw_funcs_lazy_loader_t<hb_cairo_draw_funcs_lazy_loader_t>
{
static hb_draw_funcs_t *create ()
{
hb_draw_funcs_t *funcs = hb_draw_funcs_create ();
hb_draw_funcs_set_move_to_func (funcs, hb_cairo_move_to, nullptr, nullptr);
hb_draw_funcs_set_line_to_func (funcs, hb_cairo_line_to, nullptr, nullptr);
hb_draw_funcs_set_cubic_to_func (funcs, hb_cairo_cubic_to, nullptr, nullptr);
hb_draw_funcs_set_close_path_func (funcs, hb_cairo_close_path, nullptr, nullptr);
hb_draw_funcs_make_immutable (funcs);
hb_atexit (free_static_cairo_draw_funcs);
return funcs;
}
} static_cairo_draw_funcs;
static inline
void free_static_cairo_draw_funcs ()
{
static_cairo_draw_funcs.free_instance ();
}
static hb_draw_funcs_t *
hb_cairo_draw_get_funcs ()
{
return static_cairo_draw_funcs.get_unconst ();
}
#ifdef HAVE_CAIRO_USER_FONT_FACE_SET_RENDER_COLOR_GLYPH_FUNC
static void
hb_cairo_push_transform (hb_paint_funcs_t *pfuncs HB_UNUSED,
void *paint_data,
float xx, float yx,
float xy, float yy,
float dx, float dy,
void *user_data HB_UNUSED)
{
hb_cairo_context_t *c = (hb_cairo_context_t *) paint_data;
cairo_t *cr = c->cr;
cairo_matrix_t m;
cairo_save (cr);
cairo_matrix_init (&m, (double) xx, (double) yx,
(double) xy, (double) yy,
(double) dx, (double) dy);
cairo_transform (cr, &m);
}
static void
hb_cairo_pop_transform (hb_paint_funcs_t *pfuncs HB_UNUSED,
void *paint_data,
void *user_data HB_UNUSED)
{
hb_cairo_context_t *c = (hb_cairo_context_t *) paint_data;
cairo_t *cr = c->cr;
cairo_restore (cr);
}
static hb_bool_t
hb_cairo_paint_color_glyph (hb_paint_funcs_t *pfuncs HB_UNUSED,
void *paint_data,
hb_codepoint_t glyph,
hb_font_t *font,
void *user_data HB_UNUSED)
{
hb_cairo_context_t *c = (hb_cairo_context_t *) paint_data;
cairo_t *cr = c->cr;
cairo_save (cr);
hb_position_t x_scale, y_scale;
hb_font_get_scale (font, &x_scale, &y_scale);
cairo_scale (cr, x_scale, y_scale);
cairo_glyph_t cairo_glyph = { glyph, 0, 0 };
cairo_set_scaled_font (cr, c->scaled_font);
cairo_set_font_size (cr, 1);
cairo_show_glyphs (cr, &cairo_glyph, 1);
cairo_restore (cr);
return true;
}
static void
hb_cairo_push_clip_glyph (hb_paint_funcs_t *pfuncs HB_UNUSED,
void *paint_data,
hb_codepoint_t glyph,
hb_font_t *font,
void *user_data HB_UNUSED)
{
hb_cairo_context_t *c = (hb_cairo_context_t *) paint_data;
cairo_t *cr = c->cr;
cairo_save (cr);
cairo_new_path (cr);
hb_font_draw_glyph (font, glyph, hb_cairo_draw_get_funcs (), cr);
cairo_close_path (cr);
cairo_clip (cr);
}
static void
hb_cairo_push_clip_rectangle (hb_paint_funcs_t *pfuncs HB_UNUSED,
void *paint_data,
float xmin, float ymin, float xmax, float ymax,
void *user_data HB_UNUSED)
{
hb_cairo_context_t *c = (hb_cairo_context_t *) paint_data;
cairo_t *cr = c->cr;
cairo_save (cr);
cairo_rectangle (cr,
(double) xmin, (double) ymin,
(double) (xmax - xmin), (double) (ymax - ymin));
cairo_clip (cr);
}
static void
hb_cairo_pop_clip (hb_paint_funcs_t *pfuncs HB_UNUSED,
void *paint_data,
void *user_data HB_UNUSED)
{
hb_cairo_context_t *c = (hb_cairo_context_t *) paint_data;
cairo_t *cr = c->cr;
cairo_restore (cr);
}
static void
hb_cairo_push_group (hb_paint_funcs_t *pfuncs HB_UNUSED,
void *paint_data,
void *user_data HB_UNUSED)
{
hb_cairo_context_t *c = (hb_cairo_context_t *) paint_data;
cairo_t *cr = c->cr;
cairo_save (cr);
cairo_push_group (cr);
}
static void
hb_cairo_pop_group (hb_paint_funcs_t *pfuncs HB_UNUSED,
void *paint_data,
hb_paint_composite_mode_t mode,
void *user_data HB_UNUSED)
{
hb_cairo_context_t *c = (hb_cairo_context_t *) paint_data;
cairo_t *cr = c->cr;
cairo_pop_group_to_source (cr);
cairo_set_operator (cr, _hb_paint_composite_mode_to_cairo (mode));
cairo_paint (cr);
cairo_restore (cr);
}
static void
hb_cairo_paint_color (hb_paint_funcs_t *pfuncs HB_UNUSED,
void *paint_data,
hb_bool_t use_foreground,
hb_color_t color,
void *user_data HB_UNUSED)
{
hb_cairo_context_t *c = (hb_cairo_context_t *) paint_data;
cairo_t *cr = c->cr;
if (use_foreground)
{
#ifdef HAVE_CAIRO_USER_SCALED_FONT_GET_FOREGROUND_SOURCE
double r, g, b, a;
cairo_pattern_t *foreground = cairo_user_scaled_font_get_foreground_source (c->scaled_font);
if (cairo_pattern_get_rgba (foreground, &r, &g, &b, &a) == CAIRO_STATUS_SUCCESS)
cairo_set_source_rgba (cr, r, g, b, a * hb_color_get_alpha (color) / 255.);
else
#endif
cairo_set_source_rgba (cr, 0, 0, 0, hb_color_get_alpha (color) / 255.);
}
else
cairo_set_source_rgba (cr,
hb_color_get_red (color) / 255.,
hb_color_get_green (color) / 255.,
hb_color_get_blue (color) / 255.,
hb_color_get_alpha (color) / 255.);
cairo_paint (cr);
}
static hb_bool_t
hb_cairo_paint_image (hb_paint_funcs_t *pfuncs HB_UNUSED,
void *paint_data,
hb_blob_t *blob,
unsigned width,
unsigned height,
hb_tag_t format,
float slant,
hb_glyph_extents_t *extents,
void *user_data HB_UNUSED)
{
hb_cairo_context_t *c = (hb_cairo_context_t *) paint_data;
return _hb_cairo_paint_glyph_image (c, blob, width, height, format, slant, extents);
}
static void
hb_cairo_paint_linear_gradient (hb_paint_funcs_t *pfuncs HB_UNUSED,
void *paint_data,
hb_color_line_t *color_line,
float x0, float y0,
float x1, float y1,
float x2, float y2,
void *user_data HB_UNUSED)
{
hb_cairo_context_t *c = (hb_cairo_context_t *) paint_data;
_hb_cairo_paint_linear_gradient (c, color_line, x0, y0, x1, y1, x2, y2);
}
static void
hb_cairo_paint_radial_gradient (hb_paint_funcs_t *pfuncs HB_UNUSED,
void *paint_data,
hb_color_line_t *color_line,
float x0, float y0, float r0,
float x1, float y1, float r1,
void *user_data HB_UNUSED)
{
hb_cairo_context_t *c = (hb_cairo_context_t *) paint_data;
_hb_cairo_paint_radial_gradient (c, color_line, x0, y0, r0, x1, y1, r1);
}
static void
hb_cairo_paint_sweep_gradient (hb_paint_funcs_t *pfuncs HB_UNUSED,
void *paint_data,
hb_color_line_t *color_line,
float x0, float y0,
float start_angle, float end_angle,
void *user_data HB_UNUSED)
{
hb_cairo_context_t *c = (hb_cairo_context_t *) paint_data;
_hb_cairo_paint_sweep_gradient (c, color_line, x0, y0, start_angle, end_angle);
}
static const cairo_user_data_key_t color_cache_key = {0};
static void
_hb_cairo_destroy_map (void *p)
{
hb_map_destroy ((hb_map_t *) p);
}
static hb_bool_t
hb_cairo_paint_custom_palette_color (hb_paint_funcs_t *funcs,
void *paint_data,
unsigned int color_index,
hb_color_t *color,
void *user_data HB_UNUSED)
{
#ifdef HAVE_CAIRO_FONT_OPTIONS_GET_CUSTOM_PALETTE_COLOR
hb_cairo_context_t *c = (hb_cairo_context_t *) paint_data;
cairo_t *cr = c->cr;
#define HB_DEADBEEF HB_TAG(0xDE,0xAD,0xBE,0xEF)
hb_map_t *color_cache = c->color_cache;
hb_codepoint_t *v;
if (likely (color_cache && color_cache->has (color_index, &v)))
{
if (*v == HB_DEADBEEF)
return false;
*color = *v;
return true;
}
cairo_font_options_t *options;
double red, green, blue, alpha;
options = cairo_font_options_create ();
cairo_get_font_options (cr, options);
if (CAIRO_STATUS_SUCCESS ==
cairo_font_options_get_custom_palette_color (options, color_index,
&red, &green, &blue, &alpha))
{
cairo_font_options_destroy (options);
*color = HB_COLOR (round (255 * blue),
round (255 * green),
round (255 * red),
round (255 * alpha));
if (likely (color_cache && *color != HB_DEADBEEF))
color_cache->set (color_index, *color);
return true;
}
cairo_font_options_destroy (options);
if (likely (color_cache))
color_cache->set (color_index, HB_DEADBEEF);
#undef HB_DEADBEEF
#endif
return false;
}
static inline void free_static_cairo_paint_funcs ();
static struct hb_cairo_paint_funcs_lazy_loader_t : hb_paint_funcs_lazy_loader_t<hb_cairo_paint_funcs_lazy_loader_t>
{
static hb_paint_funcs_t *create ()
{
hb_paint_funcs_t *funcs = hb_paint_funcs_create ();
hb_paint_funcs_set_push_transform_func (funcs, hb_cairo_push_transform, nullptr, nullptr);
hb_paint_funcs_set_pop_transform_func (funcs, hb_cairo_pop_transform, nullptr, nullptr);
hb_paint_funcs_set_color_glyph_func (funcs, hb_cairo_paint_color_glyph, nullptr, nullptr);
hb_paint_funcs_set_push_clip_glyph_func (funcs, hb_cairo_push_clip_glyph, nullptr, nullptr);
hb_paint_funcs_set_push_clip_rectangle_func (funcs, hb_cairo_push_clip_rectangle, nullptr, nullptr);
hb_paint_funcs_set_pop_clip_func (funcs, hb_cairo_pop_clip, nullptr, nullptr);
hb_paint_funcs_set_push_group_func (funcs, hb_cairo_push_group, nullptr, nullptr);
hb_paint_funcs_set_pop_group_func (funcs, hb_cairo_pop_group, nullptr, nullptr);
hb_paint_funcs_set_color_func (funcs, hb_cairo_paint_color, nullptr, nullptr);
hb_paint_funcs_set_image_func (funcs, hb_cairo_paint_image, nullptr, nullptr);
hb_paint_funcs_set_linear_gradient_func (funcs, hb_cairo_paint_linear_gradient, nullptr, nullptr);
hb_paint_funcs_set_radial_gradient_func (funcs, hb_cairo_paint_radial_gradient, nullptr, nullptr);
hb_paint_funcs_set_sweep_gradient_func (funcs, hb_cairo_paint_sweep_gradient, nullptr, nullptr);
hb_paint_funcs_set_custom_palette_color_func (funcs, hb_cairo_paint_custom_palette_color, nullptr, nullptr);
hb_paint_funcs_make_immutable (funcs);
hb_atexit (free_static_cairo_paint_funcs);
return funcs;
}
} static_cairo_paint_funcs;
static inline
void free_static_cairo_paint_funcs ()
{
static_cairo_paint_funcs.free_instance ();
}
static hb_paint_funcs_t *
hb_cairo_paint_get_funcs ()
{
return static_cairo_paint_funcs.get_unconst ();
}
#endif
static const cairo_user_data_key_t hb_cairo_face_user_data_key = {0};
static const cairo_user_data_key_t hb_cairo_font_user_data_key = {0};
static const cairo_user_data_key_t hb_cairo_font_init_func_user_data_key = {0};
static const cairo_user_data_key_t hb_cairo_font_init_user_data_user_data_key = {0};
static const cairo_user_data_key_t hb_cairo_scale_factor_user_data_key = {0};
static void hb_cairo_face_destroy (void *p) { hb_face_destroy ((hb_face_t *) p); }
static void hb_cairo_font_destroy (void *p) { hb_font_destroy ((hb_font_t *) p); }
static cairo_status_t
hb_cairo_init_scaled_font (cairo_scaled_font_t *scaled_font,
cairo_t *cr HB_UNUSED,
cairo_font_extents_t *extents)
{
cairo_font_face_t *font_face = cairo_scaled_font_get_font_face (scaled_font);
hb_font_t *font = (hb_font_t *) cairo_font_face_get_user_data (font_face,
&hb_cairo_font_user_data_key);
if (!font)
{
hb_face_t *face = (hb_face_t *) cairo_font_face_get_user_data (font_face,
&hb_cairo_face_user_data_key);
font = hb_font_create (face);
#if !defined(HB_NO_VAR) && CAIRO_VERSION >= CAIRO_VERSION_ENCODE(1,16,0)
cairo_font_options_t *font_options = cairo_font_options_create ();
// Set variations
cairo_scaled_font_get_font_options (scaled_font, font_options);
const char *variations = cairo_font_options_get_variations (font_options);
hb_vector_t<hb_variation_t> vars;
const char *p = variations;
while (p && *p)
{
const char *end = strpbrk ((char *) p, ", ");
hb_variation_t var;
if (hb_variation_from_string (p, end ? end - p : -1, &var))
vars.push (var);
p = end ? end + 1 : nullptr;
}
hb_font_set_variations (font, &vars[0], vars.length);
cairo_font_options_destroy (font_options);
#endif
// Set scale; Note: should NOT set slant, or we'll double-slant.
unsigned scale_factor = hb_cairo_font_face_get_scale_factor (font_face);
if (scale_factor)
{
cairo_matrix_t font_matrix;
cairo_scaled_font_get_scale_matrix (scaled_font, &font_matrix);
hb_font_set_scale (font,
round (font_matrix.xx * scale_factor),
round (font_matrix.yy * scale_factor));
}
auto *init_func = (hb_cairo_font_init_func_t)
cairo_font_face_get_user_data (font_face,
&hb_cairo_font_init_func_user_data_key);
if (init_func)
{
void *user_data = cairo_font_face_get_user_data (font_face,
&hb_cairo_font_init_user_data_user_data_key);
font = init_func (font, scaled_font, user_data);
}
hb_font_make_immutable (font);
}
cairo_scaled_font_set_user_data (scaled_font,
&hb_cairo_font_user_data_key,
(void *) hb_font_reference (font),
hb_cairo_font_destroy);
hb_position_t x_scale, y_scale;
hb_font_get_scale (font, &x_scale, &y_scale);
hb_font_extents_t hb_extents;
hb_font_get_h_extents (font, &hb_extents);
extents->ascent = (double) hb_extents.ascender / y_scale;
extents->descent = (double) -hb_extents.descender / y_scale;
extents->height = extents->ascent + extents->descent;
#ifdef HAVE_CAIRO_USER_FONT_FACE_SET_RENDER_COLOR_GLYPH_FUNC
hb_map_t *color_cache = hb_map_create ();
if (unlikely (CAIRO_STATUS_SUCCESS != cairo_scaled_font_set_user_data (scaled_font,
&color_cache_key,
color_cache,
_hb_cairo_destroy_map)))
hb_map_destroy (color_cache);
#endif
return CAIRO_STATUS_SUCCESS;
}
static cairo_status_t
hb_cairo_text_to_glyphs (cairo_scaled_font_t *scaled_font,
const char *utf8,
int utf8_len,
cairo_glyph_t **glyphs,
int *num_glyphs,
cairo_text_cluster_t **clusters,
int *num_clusters,
cairo_text_cluster_flags_t *cluster_flags)
{
hb_font_t *font = (hb_font_t *) cairo_scaled_font_get_user_data (scaled_font,
&hb_cairo_font_user_data_key);
hb_buffer_t *buffer = hb_buffer_create ();
hb_buffer_add_utf8 (buffer, utf8, utf8_len, 0, utf8_len);
hb_buffer_guess_segment_properties (buffer);
hb_shape (font, buffer, nullptr, 0);
hb_cairo_glyphs_from_buffer (buffer,
true,
font->x_scale, font->y_scale,
0., 0.,
utf8, utf8_len,
glyphs, (unsigned *) num_glyphs,
clusters, (unsigned *) num_clusters,
cluster_flags);
hb_buffer_destroy (buffer);
return CAIRO_STATUS_SUCCESS;
}
static cairo_status_t
hb_cairo_render_glyph (cairo_scaled_font_t *scaled_font,
unsigned long glyph,
cairo_t *cr,
cairo_text_extents_t *extents)
{
hb_font_t *font = (hb_font_t *) cairo_scaled_font_get_user_data (scaled_font,
&hb_cairo_font_user_data_key);
hb_position_t x_scale, y_scale;
hb_font_get_scale (font, &x_scale, &y_scale);
cairo_scale (cr, +1./x_scale, -1./y_scale);
hb_font_draw_glyph (font, glyph, hb_cairo_draw_get_funcs (), cr);
cairo_fill (cr);
return CAIRO_STATUS_SUCCESS;
}
#ifdef HAVE_CAIRO_USER_FONT_FACE_SET_RENDER_COLOR_GLYPH_FUNC
static cairo_status_t
hb_cairo_render_color_glyph (cairo_scaled_font_t *scaled_font,
unsigned long glyph,
cairo_t *cr,
cairo_text_extents_t *extents)
{
hb_font_t *font = (hb_font_t *) cairo_scaled_font_get_user_data (scaled_font,
&hb_cairo_font_user_data_key);
unsigned int palette = 0;
#ifdef CAIRO_COLOR_PALETTE_DEFAULT
cairo_font_options_t *options = cairo_font_options_create ();
cairo_scaled_font_get_font_options (scaled_font, options);
palette = cairo_font_options_get_color_palette (options);
cairo_font_options_destroy (options);
#endif
hb_color_t color = HB_COLOR (0, 0, 0, 255);
hb_position_t x_scale, y_scale;
hb_font_get_scale (font, &x_scale, &y_scale);
cairo_scale (cr, +1./x_scale, -1./y_scale);
hb_cairo_context_t c;
c.scaled_font = scaled_font;
c.cr = cr;
c.color_cache = (hb_map_t *) cairo_scaled_font_get_user_data (scaled_font, &color_cache_key);
hb_font_paint_glyph (font, glyph, hb_cairo_paint_get_funcs (), &c, palette, color);
return CAIRO_STATUS_SUCCESS;
}
#endif
static cairo_font_face_t *
user_font_face_create (hb_face_t *face)
{
cairo_font_face_t *cairo_face;
cairo_face = cairo_user_font_face_create ();
cairo_user_font_face_set_init_func (cairo_face, hb_cairo_init_scaled_font);
cairo_user_font_face_set_text_to_glyphs_func (cairo_face, hb_cairo_text_to_glyphs);
cairo_user_font_face_set_render_glyph_func (cairo_face, hb_cairo_render_glyph);
#ifdef HAVE_CAIRO_USER_FONT_FACE_SET_RENDER_COLOR_GLYPH_FUNC
if (hb_ot_color_has_png (face) || hb_ot_color_has_layers (face) || hb_ot_color_has_paint (face))
cairo_user_font_face_set_render_color_glyph_func (cairo_face, hb_cairo_render_color_glyph);
#endif
if (unlikely (CAIRO_STATUS_SUCCESS != cairo_font_face_set_user_data (cairo_face,
&hb_cairo_face_user_data_key,
(void *) hb_face_reference (face),
hb_cairo_face_destroy)))
hb_face_destroy (face);
return cairo_face;
}
/**
* hb_cairo_font_face_create_for_font:
* @font: a #hb_font_t
*
* Creates a #cairo_font_face_t for rendering text according
* to @font.
*
* Note that the scale of @font does not affect the rendering,
* but the variations and slant that are set on @font do.
*
* Returns: (transfer full): a newly created #cairo_font_face_t
*
* Since: 7.0.0
*/
cairo_font_face_t *
hb_cairo_font_face_create_for_font (hb_font_t *font)
{
hb_font_make_immutable (font);
auto *cairo_face = user_font_face_create (font->face);
if (unlikely (CAIRO_STATUS_SUCCESS != cairo_font_face_set_user_data (cairo_face,
&hb_cairo_font_user_data_key,
(void *) hb_font_reference (font),
hb_cairo_font_destroy)))
hb_font_destroy (font);
return cairo_face;
}
/**
* hb_cairo_font_face_get_font:
* @font_face: a #cairo_font_face_t
*
* Gets the #hb_font_t that @font_face was created from.
*
* Returns: (nullable) (transfer none): the #hb_font_t that @font_face was created from
*
* Since: 7.0.0
*/
hb_font_t *
hb_cairo_font_face_get_font (cairo_font_face_t *font_face)
{
return (hb_font_t *) cairo_font_face_get_user_data (font_face,
&hb_cairo_font_user_data_key);
}
/**
* hb_cairo_font_face_create_for_face:
* @face: a #hb_face_t
*
* Creates a #cairo_font_face_t for rendering text according
* to @face.
*
* Returns: (transfer full): a newly created #cairo_font_face_t
*
* Since: 7.0.0
*/
cairo_font_face_t *
hb_cairo_font_face_create_for_face (hb_face_t *face)
{
hb_face_make_immutable (face);
return user_font_face_create (face);
}
/**
* hb_cairo_font_face_get_face:
* @font_face: a #cairo_font_face_t
*
* Gets the #hb_face_t associated with @font_face.
*
* Returns: (nullable) (transfer none): the #hb_face_t associated with @font_face
*
* Since: 7.0.0
*/
hb_face_t *
hb_cairo_font_face_get_face (cairo_font_face_t *font_face)
{
return (hb_face_t *) cairo_font_face_get_user_data (font_face,
&hb_cairo_face_user_data_key);
}
/**
* hb_cairo_font_face_set_font_init_func:
* @font_face: a #cairo_font_face_t
* @func: The virtual method to use
* @user_data: user data accompanying the method
* @destroy: function to call when @user_data is not needed anymore
*
* Set the virtual method to be called when a cairo
* face created using hb_cairo_font_face_create_for_face()
* creates an #hb_font_t for a #cairo_scaled_font_t.
*
* Since: 7.0.0
*/
void
hb_cairo_font_face_set_font_init_func (cairo_font_face_t *font_face,
hb_cairo_font_init_func_t func,
void *user_data,
hb_destroy_func_t destroy)
{
cairo_font_face_set_user_data (font_face,
&hb_cairo_font_init_func_user_data_key,
(void *) func,
nullptr);
if (unlikely (CAIRO_STATUS_SUCCESS != cairo_font_face_set_user_data (font_face,
&hb_cairo_font_init_user_data_user_data_key,
(void *) user_data,
destroy)) && destroy)
{
destroy (user_data);
cairo_font_face_set_user_data (font_face,
&hb_cairo_font_init_func_user_data_key,
nullptr,
nullptr);
}
}
/**
* hb_cairo_scaled_font_get_font:
* @scaled_font: a #cairo_scaled_font_t
*
* Gets the #hb_font_t associated with @scaled_font.
*
* Returns: (nullable) (transfer none): the #hb_font_t associated with @scaled_font
*
* Since: 7.0.0
*/
hb_font_t *
hb_cairo_scaled_font_get_font (cairo_scaled_font_t *scaled_font)
{
return (hb_font_t *) cairo_scaled_font_get_user_data (scaled_font, &hb_cairo_font_user_data_key);
}
/**
* hb_cairo_font_face_set_scale_factor:
* @scale_factor: The scale factor to use. See below
* @font_face: a #cairo_font_face_t
*
* Sets the scale factor of the @font_face. Default scale
* factor is zero.
*
* When a #cairo_font_face_t is created from a #hb_face_t using
* hb_cairo_font_face_create_for_face(), such face will create
* #hb_font_t objects during scaled-font creation. The scale
* factor defines how the scale set on such #hb_font_t objects
* relates to the font-matrix (as such font size) of the cairo
* scaled-font.
*
* If the scale-factor is zero (default), then the scale of the
* #hb_font_t object will be left at default, which is the UPEM
* value of the respective #hb_face_t.
*
* If the scale-factor is set to non-zero, then the X and Y scale
* of the #hb_font_t object will be respectively set to the
* @scale_factor times the xx and yy elements of the scale-matrix
* of the cairo scaled-font being created.
*
* When using the hb_cairo_glyphs_from_buffer() API to convert the
* HarfBuzz glyph buffer that resulted from shaping with such a #hb_font_t,
* if the scale-factor was non-zero, you can pass it directly to
* that API as both X and Y scale factors.
*
* If the scale-factor was zero however, or the cairo face was
* created using the alternative constructor
* hb_cairo_font_face_create_for_font(), you need to calculate the
* correct X/Y scale-factors to pass to hb_cairo_glyphs_from_buffer()
* by dividing the #hb_font_t X/Y scale-factors by the
* cairo scaled-font's scale-matrix XX/YY components respectively
* and use those values. Or if you know that relationship offhand
* (because you set the scale of the #hb_font_t yourself), use
* the conversion rate involved.
*
* Since: 7.0.0
*/
void
hb_cairo_font_face_set_scale_factor (cairo_font_face_t *font_face,
unsigned int scale_factor)
{
cairo_font_face_set_user_data (font_face,
&hb_cairo_scale_factor_user_data_key,
(void *) (uintptr_t) scale_factor,
nullptr);
}
/**
* hb_cairo_font_face_get_scale_factor:
* @font_face: a #cairo_font_face_t
*
* Gets the scale factor set on the @font_face. Defaults to zero.
* See hb_cairo_font_face_set_scale_factor() for details.
*
* Returns: the scale factor of @font_face
*
* Since: 7.0.0
*/
unsigned int
hb_cairo_font_face_get_scale_factor (cairo_font_face_t *font_face)
{
return (unsigned int) (uintptr_t)
cairo_font_face_get_user_data (font_face,
&hb_cairo_scale_factor_user_data_key);
}
/**
* hb_cairo_glyphs_from_buffer:
* @buffer: a #hb_buffer_t containing glyphs
* @utf8_clusters: `true` if @buffer clusters are in bytes, instead of characters
* @x_scale_factor: scale factor to divide #hb_position_t Y values by
* @y_scale_factor: scale factor to divide #hb_position_t X values by
* @x: X position to place first glyph
* @y: Y position to place first glyph
* @utf8: (nullable): the text that was shaped in @buffer
* @utf8_len: the length of @utf8 in bytes
* @glyphs: (out): return location for an array of #cairo_glyph_t
* @num_glyphs: (inout): return location for the length of @glyphs
* @clusters: (out) (nullable): return location for an array of cluster positions
* @num_clusters: (inout) (nullable): return location for the length of @clusters
* @cluster_flags: (out) (nullable): return location for cluster flags
*
* Extracts information from @buffer in a form that can be
* passed to cairo_show_text_glyphs() or cairo_show_glyphs().
* This API is modeled after cairo_scaled_font_text_to_glyphs() and
* cairo_user_scaled_font_text_to_glyphs_func_t.
*
* The @num_glyphs argument should be preset to the number of glyph entries available
* in the @glyphs buffer. If the @glyphs buffer is `NULL`, the value of
* @num_glyphs must be zero. If the provided glyph array is too short for
* the conversion (or for convenience), a new glyph array may be allocated
* using cairo_glyph_allocate() and placed in @glyphs. Upon return,
* @num_glyphs should contain the number of generated glyphs. If the value
* @glyphs points at has changed after the call, the caller will free the
* allocated glyph array using cairo_glyph_free(). The caller will also free
* the original value of @glyphs, so this function shouldn't do so.
*
* If @clusters is not `NULL`, then @num_clusters and @cluster_flags
* should not be either, and @utf8 must be provided, and cluster
* mapping will be computed. The semantics of how
* cluster array allocation works is similar to the glyph array. That is,
* if @clusters initially points to a non-`NULL` value, that array may be used
* as a cluster buffer, and @num_clusters points to the number of cluster
* entries available there. If the provided cluster array is too short for
* the conversion (or for convenience), a new cluster array may be allocated
* using cairo_text_cluster_allocate() and placed in @clusters. In this case,
* the original value of @clusters will still be freed by the caller. Upon
* return, @num_clusters will contain the number of generated clusters.
* If the value @clusters points at has changed after the call, the caller
* will free the allocated cluster array using cairo_text_cluster_free().
*
* See hb_cairo_font_face_set_scale_factor() for the details of
* the @scale_factor argument.
*
* The returned @glyphs vector actually has `@num_glyphs + 1` entries in
* it and the x,y values of the extra entry at the end add up the advance
* x,y of all the glyphs in the @buffer.
*
* Since: 7.0.0
*/
void
hb_cairo_glyphs_from_buffer (hb_buffer_t *buffer,
hb_bool_t utf8_clusters,
double x_scale_factor,
double y_scale_factor,
double x,
double y,
const char *utf8,
int utf8_len,
cairo_glyph_t **glyphs,
unsigned int *num_glyphs,
cairo_text_cluster_t **clusters,
unsigned int *num_clusters,
cairo_text_cluster_flags_t *cluster_flags)
{
if (utf8 && utf8_len < 0)
utf8_len = strlen (utf8);
unsigned orig_num_glyphs = *num_glyphs;
*num_glyphs = hb_buffer_get_length (buffer);
hb_glyph_info_t *hb_glyph = hb_buffer_get_glyph_infos (buffer, nullptr);
hb_glyph_position_t *hb_position = hb_buffer_get_glyph_positions (buffer, nullptr);
if (orig_num_glyphs < *num_glyphs + 1)
*glyphs = cairo_glyph_allocate (*num_glyphs + 1);
if (clusters && utf8)
{
unsigned orig_num_clusters = *num_clusters;
*num_clusters = *num_glyphs ? 1 : 0;
for (unsigned int i = 1; i < *num_glyphs; i++)
if (hb_glyph[i].cluster != hb_glyph[i-1].cluster)
(*num_clusters)++;
if (orig_num_clusters < *num_clusters)
*clusters = cairo_text_cluster_allocate (*num_clusters);
}
double x_scale = x_scale_factor ? 1. / x_scale_factor : 0.;
double y_scale = y_scale_factor ? 1. / y_scale_factor : 0.;
hb_position_t hx = 0, hy = 0;
int i;
for (i = 0; i < (int) *num_glyphs; i++)
{
(*glyphs)[i].index = hb_glyph[i].codepoint;
(*glyphs)[i].x = x + (+hb_position->x_offset + hx) * x_scale;
(*glyphs)[i].y = y + (-hb_position->y_offset + hy) * y_scale;
hx += hb_position->x_advance;
hy += -hb_position->y_advance;
hb_position++;
}
(*glyphs)[i].index = -1;
(*glyphs)[i].x = round (hx * x_scale);
(*glyphs)[i].y = round (hy * y_scale);
if (clusters && *num_clusters && utf8)
{
hb_memset ((void *) *clusters, 0, *num_clusters * sizeof ((*clusters)[0]));
hb_bool_t backward = HB_DIRECTION_IS_BACKWARD (hb_buffer_get_direction (buffer));
*cluster_flags = backward ? CAIRO_TEXT_CLUSTER_FLAG_BACKWARD : (cairo_text_cluster_flags_t) 0;
unsigned int cluster = 0;
const char *start = utf8, *end;
(*clusters)[cluster].num_glyphs++;
if (backward)
{
for (i = *num_glyphs - 2; i >= 0; i--)
{
if (hb_glyph[i].cluster != hb_glyph[i+1].cluster)
{
assert (hb_glyph[i].cluster > hb_glyph[i+1].cluster);
if (utf8_clusters)
end = start + hb_glyph[i].cluster - hb_glyph[i+1].cluster;
else
end = (const char *) hb_utf_offset_to_pointer<hb_utf8_t> ((const uint8_t *) start,
(signed) (hb_glyph[i].cluster - hb_glyph[i+1].cluster));
(*clusters)[cluster].num_bytes = end - start;
start = end;
cluster++;
}
(*clusters)[cluster].num_glyphs++;
}
(*clusters)[cluster].num_bytes = utf8 + utf8_len - start;
}
else
{
for (i = 1; i < (int) *num_glyphs; i++)
{
if (hb_glyph[i].cluster != hb_glyph[i-1].cluster)
{
assert (hb_glyph[i].cluster > hb_glyph[i-1].cluster);
if (utf8_clusters)
end = start + hb_glyph[i].cluster - hb_glyph[i-1].cluster;
else
end = (const char *) hb_utf_offset_to_pointer<hb_utf8_t> ((const uint8_t *) start,
(signed) (hb_glyph[i].cluster - hb_glyph[i-1].cluster));
(*clusters)[cluster].num_bytes = end - start;
start = end;
cluster++;
}
(*clusters)[cluster].num_glyphs++;
}
(*clusters)[cluster].num_bytes = utf8 + utf8_len - start;
}
}
else if (num_clusters)
*num_clusters = 0;
}
#endif