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/* -*- Mode: c; tab-width: 8; c-basic-offset: 4; indent-tabs-mode: t; -*- */
/* cairo - a vector graphics library with display and print output
*
* Copyright © 2006, 2008 Red Hat, Inc
*
* This library is free software; you can redistribute it and/or
* modify it either under the terms of the GNU Lesser General Public
* License version 2.1 as published by the Free Software Foundation
* (the "LGPL") or, at your option, under the terms of the Mozilla
* Public License Version 1.1 (the "MPL"). If you do not alter this
* notice, a recipient may use your version of this file under either
* the MPL or the LGPL.
*
* You should have received a copy of the LGPL along with this library
* in the file COPYING-LGPL-2.1; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
* You should have received a copy of the MPL along with this library
* in the file COPYING-MPL-1.1
*
* The contents of this file are subject to the Mozilla Public License
* Version 1.1 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
* OF ANY KIND, either express or implied. See the LGPL or the MPL for
* the specific language governing rights and limitations.
*
* The Original Code is the cairo graphics library.
*
* The Initial Developer of the Original Code is Red Hat, Inc.
*
* Contributor(s):
* Kristian Høgsberg <krh@redhat.com>
* Behdad Esfahbod <behdad@behdad.org>
*/
#include "cairoint.h"
#include "cairo-user-font-private.h"
#include "cairo-recording-surface-private.h"
#include "cairo-analysis-surface-private.h"
#include "cairo-error-private.h"
/**
* SECTION:cairo-user-fonts
* @Title:User Fonts
* @Short_Description: Font support with font data provided by the user
*
* The user-font feature allows the cairo user to provide drawings for glyphs
* in a font. This is most useful in implementing fonts in non-standard
* formats, like SVG fonts and Flash fonts, but can also be used by games and
* other application to draw "funky" fonts.
**/
/**
* CAIRO_HAS_USER_FONT:
*
* Defined if the user font backend is available.
* This macro can be used to conditionally compile backend-specific code.
* The user font backend is always built in versions of cairo that support
* this feature (1.8 and later).
*
* Since: 1.8
**/
typedef struct _cairo_user_scaled_font_methods {
cairo_user_scaled_font_init_func_t init;
cairo_user_scaled_font_render_glyph_func_t render_color_glyph;
cairo_user_scaled_font_render_glyph_func_t render_glyph;
cairo_user_scaled_font_unicode_to_glyph_func_t unicode_to_glyph;
cairo_user_scaled_font_text_to_glyphs_func_t text_to_glyphs;
} cairo_user_scaled_font_methods_t;
typedef struct _cairo_user_font_face {
cairo_font_face_t base;
/* Set to true after first scaled font is created. At that point,
* the scaled_font_methods cannot change anymore. */
cairo_bool_t immutable;
cairo_bool_t has_color;
cairo_user_scaled_font_methods_t scaled_font_methods;
} cairo_user_font_face_t;
typedef struct _cairo_user_scaled_font {
cairo_scaled_font_t base;
cairo_text_extents_t default_glyph_extents;
/* space to compute extents in, and factors to convert back to user space */
cairo_matrix_t extent_scale;
double extent_x_scale;
double extent_y_scale;
/* multiplier for metrics hinting */
double snap_x_scale;
double snap_y_scale;
cairo_pattern_t *foreground_marker;
cairo_pattern_t *foreground_pattern;
cairo_bool_t foreground_marker_used;
cairo_bool_t foreground_colors_used;
} cairo_user_scaled_font_t;
/* #cairo_user_scaled_font_t */
static cairo_surface_t *
_cairo_user_scaled_font_create_recording_surface (cairo_user_scaled_font_t *scaled_font,
cairo_bool_t color,
const cairo_color_t *foreground_color)
{
cairo_content_t content;
if (color) {
content = CAIRO_CONTENT_COLOR_ALPHA;
} else {
content = scaled_font->base.options.antialias == CAIRO_ANTIALIAS_SUBPIXEL ?
CAIRO_CONTENT_COLOR_ALPHA :
CAIRO_CONTENT_ALPHA;
}
if (scaled_font->foreground_pattern)
cairo_pattern_destroy (scaled_font->foreground_pattern);
scaled_font->foreground_marker_used = FALSE;
scaled_font->foreground_colors_used = FALSE;
if (foreground_color) {
scaled_font->foreground_pattern = _cairo_pattern_create_solid (foreground_color);
} else {
scaled_font->foreground_pattern = cairo_pattern_create_rgb (0, 0, 0);
}
return cairo_recording_surface_create (content, NULL);
}
static cairo_t *
_cairo_user_scaled_font_create_recording_context (const cairo_user_scaled_font_t *scaled_font,
cairo_surface_t *recording_surface,
cairo_bool_t color)
{
cairo_t *cr;
cr = cairo_create (recording_surface);
if (!_cairo_matrix_is_scale_0 (&scaled_font->base.scale)) {
cairo_matrix_t scale;
scale = scaled_font->base.scale;
scale.x0 = scale.y0 = 0.;
cairo_set_matrix (cr, &scale);
}
cairo_set_font_size (cr, 1.0);
cairo_set_font_options (cr, &scaled_font->base.options);
if (!color)
cairo_set_source_rgb (cr, 1., 1., 1.);
return cr;
}
static cairo_int_status_t
_cairo_user_scaled_glyph_init_record_glyph (cairo_user_scaled_font_t *scaled_font,
cairo_scaled_glyph_t *scaled_glyph,
const cairo_color_t *foreground_color)
{
cairo_user_font_face_t *face =
(cairo_user_font_face_t *) scaled_font->base.font_face;
cairo_text_extents_t extents = scaled_font->default_glyph_extents;
cairo_surface_t *recording_surface = NULL;
cairo_int_status_t status = CAIRO_STATUS_SUCCESS;
cairo_t *cr;
cairo_bool_t foreground_used = FALSE;
if (!face->scaled_font_methods.render_color_glyph && !face->scaled_font_methods.render_glyph)
return CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED;
/* special case for 0 rank matrix (as in _cairo_scaled_font_init): empty surface */
if (_cairo_matrix_is_scale_0 (&scaled_font->base.scale)) {
recording_surface = _cairo_user_scaled_font_create_recording_surface (scaled_font, FALSE, foreground_color);
_cairo_scaled_glyph_set_recording_surface (scaled_glyph,
&scaled_font->base,
recording_surface,
NULL);
} else {
status = CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED;
if (face->scaled_font_methods.render_color_glyph &&
scaled_font->base.options.color_mode != CAIRO_COLOR_MODE_NO_COLOR)
{
recording_surface = _cairo_user_scaled_font_create_recording_surface (scaled_font, TRUE, foreground_color);
cr = _cairo_user_scaled_font_create_recording_context (scaled_font, recording_surface, TRUE);
status = face->scaled_font_methods.render_color_glyph ((cairo_scaled_font_t *)scaled_font,
_cairo_scaled_glyph_index(scaled_glyph),
cr, &extents);
if (status == CAIRO_INT_STATUS_SUCCESS) {
status = cairo_status (cr);
scaled_glyph->color_glyph = TRUE;
scaled_glyph->color_glyph_set = TRUE;
}
cairo_destroy (cr);
foreground_used = scaled_font->foreground_marker_used || scaled_font->foreground_colors_used;
}
if (status == (cairo_int_status_t)CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED &&
face->scaled_font_methods.render_glyph) {
if (recording_surface)
cairo_surface_destroy (recording_surface);
recording_surface = _cairo_user_scaled_font_create_recording_surface (scaled_font, FALSE, foreground_color);
recording_surface->device_transform.x0 = .25 * _cairo_scaled_glyph_xphase (scaled_glyph);
recording_surface->device_transform.y0 = .25 * _cairo_scaled_glyph_yphase (scaled_glyph);
cr = _cairo_user_scaled_font_create_recording_context (scaled_font, recording_surface, FALSE);
status = face->scaled_font_methods.render_glyph ((cairo_scaled_font_t *)scaled_font,
_cairo_scaled_glyph_index(scaled_glyph),
cr, &extents);
if (status == CAIRO_INT_STATUS_SUCCESS) {
status = cairo_status (cr);
scaled_glyph->color_glyph = FALSE;
scaled_glyph->color_glyph_set = TRUE;
}
cairo_destroy (cr);
foreground_used = FALSE;
}
if (status != CAIRO_INT_STATUS_SUCCESS) {
if (recording_surface)
cairo_surface_destroy (recording_surface);
return status;
}
_cairo_scaled_glyph_set_recording_surface (scaled_glyph,
&scaled_font->base,
recording_surface,
foreground_used ? foreground_color : NULL);
}
/* set metrics */
if (extents.width == 0.) {
cairo_box_t bbox;
double x1, y1, x2, y2;
double x_scale, y_scale;
/* Compute extents.x/y/width/height from recording_surface,
* in font space.
*/
status = _cairo_recording_surface_get_bbox ((cairo_recording_surface_t *) recording_surface,
&bbox,
&scaled_font->extent_scale);
if (unlikely (status))
return status;
_cairo_box_to_doubles (&bbox, &x1, &y1, &x2, &y2);
x_scale = scaled_font->extent_x_scale;
y_scale = scaled_font->extent_y_scale;
extents.x_bearing = x1 * x_scale;
extents.y_bearing = y1 * y_scale;
extents.width = (x2 - x1) * x_scale;
extents.height = (y2 - y1) * y_scale;
}
if (scaled_font->base.options.hint_metrics != CAIRO_HINT_METRICS_OFF) {
extents.x_advance = _cairo_lround (extents.x_advance / scaled_font->snap_x_scale) * scaled_font->snap_x_scale;
extents.y_advance = _cairo_lround (extents.y_advance / scaled_font->snap_y_scale) * scaled_font->snap_y_scale;
}
_cairo_scaled_glyph_set_metrics (scaled_glyph,
&scaled_font->base,
&extents);
return status;
}
static cairo_int_status_t
_cairo_user_scaled_glyph_init_surface (cairo_user_scaled_font_t *scaled_font,
cairo_scaled_glyph_t *scaled_glyph,
cairo_scaled_glyph_info_t info,
const cairo_color_t *foreground_color)
{
cairo_surface_t *surface;
cairo_format_t format;
int width, height;
cairo_int_status_t status = CAIRO_STATUS_SUCCESS;
cairo_bool_t foreground_used;
/* TODO
* extend the glyph cache to support argb glyphs.
* need to figure out the semantics and interaction with subpixel
* rendering first.
*/
/* Only one info type at a time handled in this function */
assert (info == CAIRO_SCALED_GLYPH_INFO_COLOR_SURFACE || info == CAIRO_SCALED_GLYPH_INFO_SURFACE);
width = _cairo_fixed_integer_ceil (scaled_glyph->bbox.p2.x) -
_cairo_fixed_integer_floor (scaled_glyph->bbox.p1.x);
height = _cairo_fixed_integer_ceil (scaled_glyph->bbox.p2.y) -
_cairo_fixed_integer_floor (scaled_glyph->bbox.p1.y);
if (info == CAIRO_SCALED_GLYPH_INFO_COLOR_SURFACE) {
format = CAIRO_FORMAT_ARGB32;
} else {
switch (scaled_font->base.options.antialias) {
default:
case CAIRO_ANTIALIAS_DEFAULT:
case CAIRO_ANTIALIAS_FAST:
case CAIRO_ANTIALIAS_GOOD:
case CAIRO_ANTIALIAS_GRAY:
format = CAIRO_FORMAT_A8;
break;
case CAIRO_ANTIALIAS_NONE:
format = CAIRO_FORMAT_A1;
break;
case CAIRO_ANTIALIAS_BEST:
case CAIRO_ANTIALIAS_SUBPIXEL:
format = CAIRO_FORMAT_ARGB32;
break;
}
}
surface = cairo_image_surface_create (format, width, height);
cairo_surface_set_device_offset (surface,
- _cairo_fixed_integer_floor (scaled_glyph->bbox.p1.x),
- _cairo_fixed_integer_floor (scaled_glyph->bbox.p1.y));
if (info == CAIRO_SCALED_GLYPH_INFO_COLOR_SURFACE) {
status = _cairo_recording_surface_replay_with_foreground_color (scaled_glyph->recording_surface,
surface,
foreground_color,
&foreground_used);
} else {
status = _cairo_recording_surface_replay (scaled_glyph->recording_surface, surface);
foreground_used = FALSE;
}
if (unlikely (status)) {
cairo_surface_destroy(surface);
return status;
}
foreground_used = foreground_used || scaled_glyph->recording_uses_foreground_color;
if (info == CAIRO_SCALED_GLYPH_INFO_COLOR_SURFACE) {
_cairo_scaled_glyph_set_color_surface (scaled_glyph,
&scaled_font->base,
(cairo_image_surface_t *)surface,
foreground_used ? foreground_color : NULL);
surface = NULL;
} else {
_cairo_scaled_glyph_set_surface (scaled_glyph,
&scaled_font->base,
(cairo_image_surface_t *) surface);
surface = NULL;
}
if (surface)
cairo_surface_destroy (surface);
return status;
}
static void
_cairo_user_scaled_glyph_fini (void *abstract_font)
{
cairo_user_scaled_font_t *scaled_font = abstract_font;
if (scaled_font->foreground_pattern)
cairo_pattern_destroy (scaled_font->foreground_pattern);
if (scaled_font->foreground_marker)
cairo_pattern_destroy (scaled_font->foreground_marker);
}
static cairo_int_status_t
_cairo_user_scaled_glyph_init (void *abstract_font,
cairo_scaled_glyph_t *scaled_glyph,
cairo_scaled_glyph_info_t info,
const cairo_color_t *foreground_color)
{
cairo_int_status_t status = CAIRO_STATUS_SUCCESS;
cairo_user_scaled_font_t *scaled_font = abstract_font;
if (!scaled_glyph->recording_surface || (info & CAIRO_SCALED_GLYPH_INFO_RECORDING_SURFACE)) {
status = _cairo_user_scaled_glyph_init_record_glyph (scaled_font, scaled_glyph, foreground_color);
if (status)
return status;
}
if (info & CAIRO_SCALED_GLYPH_INFO_COLOR_SURFACE) {
if (!scaled_glyph->color_glyph )
return CAIRO_INT_STATUS_UNSUPPORTED;
status = _cairo_user_scaled_glyph_init_surface (scaled_font,
scaled_glyph,
CAIRO_SCALED_GLYPH_INFO_COLOR_SURFACE,
foreground_color);
if (status)
return status;
}
if (info & CAIRO_SCALED_GLYPH_INFO_SURFACE) {
status = _cairo_user_scaled_glyph_init_surface (scaled_font,
scaled_glyph,
CAIRO_SCALED_GLYPH_INFO_SURFACE,
NULL);
if (status)
return status;
}
if (info & CAIRO_SCALED_GLYPH_INFO_PATH) {
cairo_path_fixed_t *path = _cairo_path_fixed_create ();
if (!path)
return _cairo_error (CAIRO_STATUS_NO_MEMORY);
status = _cairo_recording_surface_get_path (scaled_glyph->recording_surface, path);
if (unlikely (status)) {
_cairo_path_fixed_destroy (path);
return status;
}
_cairo_scaled_glyph_set_path (scaled_glyph,
&scaled_font->base,
path);
}
return status;
}
static unsigned long
_cairo_user_ucs4_to_index (void *abstract_font,
uint32_t ucs4)
{
cairo_user_scaled_font_t *scaled_font = abstract_font;
cairo_user_font_face_t *face =
(cairo_user_font_face_t *) scaled_font->base.font_face;
unsigned long glyph = 0;
if (face->scaled_font_methods.unicode_to_glyph) {
cairo_status_t status;
status = face->scaled_font_methods.unicode_to_glyph (&scaled_font->base,
ucs4, &glyph);
if (status == CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED)
goto not_implemented;
if (status != CAIRO_STATUS_SUCCESS) {
status = _cairo_scaled_font_set_error (&scaled_font->base, status);
glyph = 0;
}
} else {
not_implemented:
glyph = ucs4;
}
return glyph;
}
static cairo_bool_t
_cairo_user_has_color_glyphs (void *abstract_font)
{
cairo_user_scaled_font_t *scaled_font = abstract_font;
cairo_user_font_face_t *face =
(cairo_user_font_face_t *) scaled_font->base.font_face;
return face->has_color;
}
static cairo_int_status_t
_cairo_user_text_to_glyphs (void *abstract_font,
double x,
double y,
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)
{
cairo_int_status_t status = CAIRO_INT_STATUS_UNSUPPORTED;
cairo_user_scaled_font_t *scaled_font = abstract_font;
cairo_user_font_face_t *face =
(cairo_user_font_face_t *) scaled_font->base.font_face;
if (face->scaled_font_methods.text_to_glyphs) {
int i;
cairo_glyph_t *orig_glyphs = *glyphs;
int orig_num_glyphs = *num_glyphs;
status = face->scaled_font_methods.text_to_glyphs (&scaled_font->base,
utf8, utf8_len,
glyphs, num_glyphs,
clusters, num_clusters, cluster_flags);
if (status != CAIRO_INT_STATUS_SUCCESS &&
status != CAIRO_INT_STATUS_USER_FONT_NOT_IMPLEMENTED)
return status;
if (status == CAIRO_INT_STATUS_USER_FONT_NOT_IMPLEMENTED ||
*num_glyphs < 0) {
if (orig_glyphs != *glyphs) {
cairo_glyph_free (*glyphs);
*glyphs = orig_glyphs;
}
*num_glyphs = orig_num_glyphs;
return CAIRO_INT_STATUS_UNSUPPORTED;
}
/* Convert from font space to user space and add x,y */
for (i = 0; i < *num_glyphs; i++) {
double gx = (*glyphs)[i].x;
double gy = (*glyphs)[i].y;
cairo_matrix_transform_point (&scaled_font->base.font_matrix,
&gx, &gy);
(*glyphs)[i].x = gx + x;
(*glyphs)[i].y = gy + y;
}
}
return status;
}
static cairo_status_t
_cairo_user_font_face_scaled_font_create (void *abstract_face,
const cairo_matrix_t *font_matrix,
const cairo_matrix_t *ctm,
const cairo_font_options_t *options,
cairo_scaled_font_t **scaled_font);
static cairo_status_t
_cairo_user_font_face_create_for_toy (cairo_toy_font_face_t *toy_face,
cairo_font_face_t **font_face)
{
return _cairo_font_face_twin_create_for_toy (toy_face, font_face);
}
static const cairo_scaled_font_backend_t _cairo_user_scaled_font_backend = {
CAIRO_FONT_TYPE_USER,
_cairo_user_scaled_glyph_fini,
_cairo_user_scaled_glyph_init,
_cairo_user_text_to_glyphs,
_cairo_user_ucs4_to_index,
NULL, /* load_truetype_table */
NULL, /* index_to_ucs4 */
NULL, /* is_synthetic */
NULL, /* index_to_glyph_name */
NULL, /* load_type1_data */
_cairo_user_has_color_glyphs,
};
/* #cairo_user_font_face_t */
static cairo_status_t
_cairo_user_font_face_scaled_font_create (void *abstract_face,
const cairo_matrix_t *font_matrix,
const cairo_matrix_t *ctm,
const cairo_font_options_t *options,
cairo_scaled_font_t **scaled_font)
{
cairo_status_t status = CAIRO_STATUS_SUCCESS;
cairo_user_font_face_t *font_face = abstract_face;
cairo_user_scaled_font_t *user_scaled_font = NULL;
cairo_font_extents_t font_extents = {1., 0., 1., 1., 0.};
font_face->immutable = TRUE;
user_scaled_font = _cairo_malloc (sizeof (cairo_user_scaled_font_t));
if (unlikely (user_scaled_font == NULL))
return _cairo_error (CAIRO_STATUS_NO_MEMORY);
status = _cairo_scaled_font_init (&user_scaled_font->base,
&font_face->base,
font_matrix, ctm, options,
&_cairo_user_scaled_font_backend);
if (unlikely (status)) {
free (user_scaled_font);
return status;
}
user_scaled_font->foreground_pattern = NULL;
user_scaled_font->foreground_marker = _cairo_pattern_create_foreground_marker ();
/* XXX metrics hinting? */
/* compute a normalized version of font scale matrix to compute
* extents in. This is to minimize error caused by the cairo_fixed_t
* representation. */
{
double fixed_scale, x_scale, y_scale;
user_scaled_font->snap_x_scale = 1.0;
user_scaled_font->snap_y_scale = 1.0;
user_scaled_font->extent_scale = user_scaled_font->base.scale_inverse;
status = _cairo_matrix_compute_basis_scale_factors (&user_scaled_font->extent_scale,
&x_scale, &y_scale,
1);
if (status == CAIRO_STATUS_SUCCESS) {
if (x_scale == 0) x_scale = 1.;
if (y_scale == 0) y_scale = 1.;
user_scaled_font->snap_x_scale = x_scale;
user_scaled_font->snap_y_scale = y_scale;
/* since glyphs are pretty much 1.0x1.0, we can reduce error by
* scaling to a larger square. say, 1024.x1024. */
fixed_scale = 1024.;
x_scale /= fixed_scale;
y_scale /= fixed_scale;
cairo_matrix_scale (&user_scaled_font->extent_scale, 1. / x_scale, 1. / y_scale);
user_scaled_font->extent_x_scale = x_scale;
user_scaled_font->extent_y_scale = y_scale;
}
}
if (status == CAIRO_STATUS_SUCCESS &&
font_face->scaled_font_methods.init != NULL)
{
/* Lock the scaled_font mutex such that user doesn't accidentally try
* to use it just yet. */
CAIRO_MUTEX_LOCK (user_scaled_font->base.mutex);
/* Give away fontmap lock such that user-font can use other fonts */
status = _cairo_scaled_font_register_placeholder_and_unlock_font_map (&user_scaled_font->base);
if (status == CAIRO_STATUS_SUCCESS) {
cairo_surface_t *recording_surface;
cairo_t *cr;
recording_surface = _cairo_user_scaled_font_create_recording_surface (user_scaled_font, FALSE, NULL);
cr = _cairo_user_scaled_font_create_recording_context (user_scaled_font, recording_surface, FALSE);
cairo_surface_destroy (recording_surface);
status = font_face->scaled_font_methods.init (&user_scaled_font->base,
cr,
&font_extents);
if (status == CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED)
status = CAIRO_STATUS_SUCCESS;
if (status == CAIRO_STATUS_SUCCESS)
status = cairo_status (cr);
cairo_destroy (cr);
_cairo_scaled_font_unregister_placeholder_and_lock_font_map (&user_scaled_font->base);
}
CAIRO_MUTEX_UNLOCK (user_scaled_font->base.mutex);
}
if (status == CAIRO_STATUS_SUCCESS)
status = _cairo_scaled_font_set_metrics (&user_scaled_font->base, &font_extents);
if (status != CAIRO_STATUS_SUCCESS) {
_cairo_scaled_font_fini (&user_scaled_font->base);
free (user_scaled_font);
} else {
user_scaled_font->default_glyph_extents.x_bearing = 0.;
user_scaled_font->default_glyph_extents.y_bearing = -font_extents.ascent;
user_scaled_font->default_glyph_extents.width = 0.;
user_scaled_font->default_glyph_extents.height = font_extents.ascent + font_extents.descent;
user_scaled_font->default_glyph_extents.x_advance = font_extents.max_x_advance;
user_scaled_font->default_glyph_extents.y_advance = 0.;
*scaled_font = &user_scaled_font->base;
}
return status;
}
const cairo_font_face_backend_t _cairo_user_font_face_backend = {
CAIRO_FONT_TYPE_USER,
_cairo_user_font_face_create_for_toy,
_cairo_font_face_destroy,
_cairo_user_font_face_scaled_font_create
};
cairo_bool_t
_cairo_font_face_is_user (cairo_font_face_t *font_face)
{
return font_face->backend == &_cairo_user_font_face_backend;
}
/* Implement the public interface */
/**
* cairo_user_font_face_create:
*
* Creates a new user font-face.
*
* Use the setter functions to associate callbacks with the returned
* user font. The only mandatory callback is render_glyph.
*
* After the font-face is created, the user can attach arbitrary data
* (the actual font data) to it using cairo_font_face_set_user_data()
* and access it from the user-font callbacks by using
* cairo_scaled_font_get_font_face() followed by
* cairo_font_face_get_user_data().
*
* Return value: a newly created #cairo_font_face_t. Free with
* cairo_font_face_destroy() when you are done using it.
*
* Since: 1.8
**/
cairo_font_face_t *
cairo_user_font_face_create (void)
{
cairo_user_font_face_t *font_face;
font_face = _cairo_malloc (sizeof (cairo_user_font_face_t));
if (!font_face) {
_cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
return (cairo_font_face_t *)&_cairo_font_face_nil;
}
_cairo_font_face_init (&font_face->base, &_cairo_user_font_face_backend);
font_face->immutable = FALSE;
font_face->has_color = FALSE;
memset (&font_face->scaled_font_methods, 0, sizeof (font_face->scaled_font_methods));
return &font_face->base;
}
/* User-font method setters */
/**
* cairo_user_font_face_set_init_func:
* @font_face: A user font face
* @init_func: The init callback, or %NULL
*
* Sets the scaled-font initialization function of a user-font.
* See #cairo_user_scaled_font_init_func_t for details of how the callback
* works.
*
* The font-face should not be immutable or a %CAIRO_STATUS_USER_FONT_IMMUTABLE
* error will occur. A user font-face is immutable as soon as a scaled-font
* is created from it.
*
* Since: 1.8
**/
void
cairo_user_font_face_set_init_func (cairo_font_face_t *font_face,
cairo_user_scaled_font_init_func_t init_func)
{
cairo_user_font_face_t *user_font_face;
if (font_face->status)
return;
if (! _cairo_font_face_is_user (font_face)) {
if (_cairo_font_face_set_error (font_face, CAIRO_STATUS_FONT_TYPE_MISMATCH))
return;
}
user_font_face = (cairo_user_font_face_t *) font_face;
if (user_font_face->immutable) {
if (_cairo_font_face_set_error (font_face, CAIRO_STATUS_USER_FONT_IMMUTABLE))
return;
}
user_font_face->scaled_font_methods.init = init_func;
}
/**
* cairo_user_font_face_set_render_color_glyph_func:
* @font_face: A user font face
* @render_glyph_func: The render_glyph callback, or %NULL
*
* Sets the color glyph rendering function of a user-font.
* See #cairo_user_scaled_font_render_glyph_func_t for details of how the callback
* works.
*
* The font-face should not be immutable or a %CAIRO_STATUS_USER_FONT_IMMUTABLE
* error will occur. A user font-face is immutable as soon as a scaled-font
* is created from it.
*
* The render_glyph callback is the only mandatory callback of a
* user-font. At least one of
* cairo_user_font_face_set_render_color_glyph_func() or
* cairo_user_font_face_set_render_glyph_func() must be called to set
* a render callback. If both callbacks are set, the color glyph
* render callback is invoked first. If the color glyph render
* callback returns %CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED, the
* non-color version of the callback is invoked.
*
* If the callback is %NULL and a glyph is tried to be rendered using
* @font_face, a %CAIRO_STATUS_USER_FONT_ERROR will occur.
*
* Since: 1.18
**/
void
cairo_user_font_face_set_render_color_glyph_func (cairo_font_face_t *font_face,
cairo_user_scaled_font_render_glyph_func_t render_glyph_func)
{
cairo_user_font_face_t *user_font_face;
if (font_face->status)
return;
if (! _cairo_font_face_is_user (font_face)) {
if (_cairo_font_face_set_error (font_face, CAIRO_STATUS_FONT_TYPE_MISMATCH))
return;
}
user_font_face = (cairo_user_font_face_t *) font_face;
if (user_font_face->immutable) {
if (_cairo_font_face_set_error (font_face, CAIRO_STATUS_USER_FONT_IMMUTABLE))
return;
}
user_font_face->scaled_font_methods.render_color_glyph = render_glyph_func;
user_font_face->has_color = render_glyph_func ? TRUE : FALSE;
}
/**
* cairo_user_font_face_set_render_glyph_func:
* @font_face: A user font face
* @render_glyph_func: The render_glyph callback, or %NULL
*
* Sets the glyph rendering function of a user-font.
* See #cairo_user_scaled_font_render_glyph_func_t for details of how the callback
* works.
*
* The font-face should not be immutable or a %CAIRO_STATUS_USER_FONT_IMMUTABLE
* error will occur. A user font-face is immutable as soon as a scaled-font
* is created from it.
*
* The render_glyph callback is the only mandatory callback of a
* user-font. At least one of
* cairo_user_font_face_set_render_color_glyph_func() or
* cairo_user_font_face_set_render_glyph_func() must be called to set
* a render callback. If both callbacks are set, the color glyph
* render callback is invoked first. If the color glyph render
* callback returns %CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED, the
* non-color version of the callback is invoked.
*
* If the callback is %NULL and a glyph is tried to be rendered using
* @font_face, a %CAIRO_STATUS_USER_FONT_ERROR will occur.
*
* Since: 1.8
**/
void
cairo_user_font_face_set_render_glyph_func (cairo_font_face_t *font_face,
cairo_user_scaled_font_render_glyph_func_t render_glyph_func)
{
cairo_user_font_face_t *user_font_face;
if (font_face->status)
return;
if (! _cairo_font_face_is_user (font_face)) {
if (_cairo_font_face_set_error (font_face, CAIRO_STATUS_FONT_TYPE_MISMATCH))
return;
}
user_font_face = (cairo_user_font_face_t *) font_face;
if (user_font_face->immutable) {
if (_cairo_font_face_set_error (font_face, CAIRO_STATUS_USER_FONT_IMMUTABLE))
return;
}
user_font_face->scaled_font_methods.render_glyph = render_glyph_func;
}
/**
* cairo_user_font_face_set_text_to_glyphs_func:
* @font_face: A user font face
* @text_to_glyphs_func: The text_to_glyphs callback, or %NULL
*
* Sets th text-to-glyphs conversion function of a user-font.
* See #cairo_user_scaled_font_text_to_glyphs_func_t for details of how the callback
* works.
*
* The font-face should not be immutable or a %CAIRO_STATUS_USER_FONT_IMMUTABLE
* error will occur. A user font-face is immutable as soon as a scaled-font
* is created from it.
*
* Since: 1.8
**/
void
cairo_user_font_face_set_text_to_glyphs_func (cairo_font_face_t *font_face,
cairo_user_scaled_font_text_to_glyphs_func_t text_to_glyphs_func)
{
cairo_user_font_face_t *user_font_face;
if (font_face->status)
return;
if (! _cairo_font_face_is_user (font_face)) {
if (_cairo_font_face_set_error (font_face, CAIRO_STATUS_FONT_TYPE_MISMATCH))
return;
}
user_font_face = (cairo_user_font_face_t *) font_face;
if (user_font_face->immutable) {
if (_cairo_font_face_set_error (font_face, CAIRO_STATUS_USER_FONT_IMMUTABLE))
return;
}
user_font_face->scaled_font_methods.text_to_glyphs = text_to_glyphs_func;
}
/**
* cairo_user_font_face_set_unicode_to_glyph_func:
* @font_face: A user font face
* @unicode_to_glyph_func: The unicode_to_glyph callback, or %NULL
*
* Sets the unicode-to-glyph conversion function of a user-font.
* See #cairo_user_scaled_font_unicode_to_glyph_func_t for details of how the callback
* works.
*
* The font-face should not be immutable or a %CAIRO_STATUS_USER_FONT_IMMUTABLE
* error will occur. A user font-face is immutable as soon as a scaled-font
* is created from it.
*
* Since: 1.8
**/
void
cairo_user_font_face_set_unicode_to_glyph_func (cairo_font_face_t *font_face,
cairo_user_scaled_font_unicode_to_glyph_func_t unicode_to_glyph_func)
{
cairo_user_font_face_t *user_font_face;
if (font_face->status)
return;
if (! _cairo_font_face_is_user (font_face)) {
if (_cairo_font_face_set_error (font_face, CAIRO_STATUS_FONT_TYPE_MISMATCH))
return;
}
user_font_face = (cairo_user_font_face_t *) font_face;
if (user_font_face->immutable) {
if (_cairo_font_face_set_error (font_face, CAIRO_STATUS_USER_FONT_IMMUTABLE))
return;
}
user_font_face->scaled_font_methods.unicode_to_glyph = unicode_to_glyph_func;
}
/* User-font method getters */
/**
* cairo_user_font_face_get_init_func:
* @font_face: A user font face
*
* Gets the scaled-font initialization function of a user-font.
*
* Return value: The init callback of @font_face
* or %NULL if none set or an error has occurred.
*
* Since: 1.8
**/
cairo_user_scaled_font_init_func_t
cairo_user_font_face_get_init_func (cairo_font_face_t *font_face)
{
cairo_user_font_face_t *user_font_face;
if (font_face->status)
return NULL;
if (! _cairo_font_face_is_user (font_face)) {
if (_cairo_font_face_set_error (font_face, CAIRO_STATUS_FONT_TYPE_MISMATCH))
return NULL;
}
user_font_face = (cairo_user_font_face_t *) font_face;
return user_font_face->scaled_font_methods.init;
}
/**
* cairo_user_font_face_get_render_color_glyph_func:
* @font_face: A user font face
*
* Gets the color glyph rendering function of a user-font.
*
* Return value: The render_glyph callback of @font_face
* or %NULL if none set or an error has occurred.
*
* Since: 1.18
**/
cairo_user_scaled_font_render_glyph_func_t
cairo_user_font_face_get_render_color_glyph_func (cairo_font_face_t *font_face)
{
cairo_user_font_face_t *user_font_face;
if (font_face->status)
return NULL;
if (! _cairo_font_face_is_user (font_face)) {
if (_cairo_font_face_set_error (font_face, CAIRO_STATUS_FONT_TYPE_MISMATCH))
return NULL;
}
user_font_face = (cairo_user_font_face_t *) font_face;
return user_font_face->scaled_font_methods.render_color_glyph;
}
/**
* cairo_user_font_face_get_render_glyph_func:
* @font_face: A user font face
*
* Gets the glyph rendering function of a user-font.
*
* Return value: The render_glyph callback of @font_face
* or %NULL if none set or an error has occurred.
*
* Since: 1.8
**/
cairo_user_scaled_font_render_glyph_func_t
cairo_user_font_face_get_render_glyph_func (cairo_font_face_t *font_face)
{
cairo_user_font_face_t *user_font_face;
if (font_face->status)
return NULL;
if (! _cairo_font_face_is_user (font_face)) {
if (_cairo_font_face_set_error (font_face, CAIRO_STATUS_FONT_TYPE_MISMATCH))
return NULL;
}
user_font_face = (cairo_user_font_face_t *) font_face;
return user_font_face->scaled_font_methods.render_glyph;
}
/**
* cairo_user_font_face_get_text_to_glyphs_func:
* @font_face: A user font face
*
* Gets the text-to-glyphs conversion function of a user-font.
*
* Return value: The text_to_glyphs callback of @font_face
* or %NULL if none set or an error occurred.
*
* Since: 1.8
**/
cairo_user_scaled_font_text_to_glyphs_func_t
cairo_user_font_face_get_text_to_glyphs_func (cairo_font_face_t *font_face)
{
cairo_user_font_face_t *user_font_face;
if (font_face->status)
return NULL;
if (! _cairo_font_face_is_user (font_face)) {
if (_cairo_font_face_set_error (font_face, CAIRO_STATUS_FONT_TYPE_MISMATCH))
return NULL;
}
user_font_face = (cairo_user_font_face_t *) font_face;
return user_font_face->scaled_font_methods.text_to_glyphs;
}
/**
* cairo_user_font_face_get_unicode_to_glyph_func:
* @font_face: A user font face
*
* Gets the unicode-to-glyph conversion function of a user-font.
*
* Return value: The unicode_to_glyph callback of @font_face
* or %NULL if none set or an error occurred.
*
* Since: 1.8
**/
cairo_user_scaled_font_unicode_to_glyph_func_t
cairo_user_font_face_get_unicode_to_glyph_func (cairo_font_face_t *font_face)
{
cairo_user_font_face_t *user_font_face;
if (font_face->status)
return NULL;
if (! _cairo_font_face_is_user (font_face)) {
if (_cairo_font_face_set_error (font_face, CAIRO_STATUS_FONT_TYPE_MISMATCH))
return NULL;
}
user_font_face = (cairo_user_font_face_t *) font_face;
return user_font_face->scaled_font_methods.unicode_to_glyph;
}
/**
* cairo_user_scaled_font_get_foreground_marker:
* @scaled_font: A user scaled font
*
* Gets the foreground pattern of the glyph currently being
* rendered. A #cairo_user_scaled_font_render_glyph_func_t function
* that has been set with
* cairo_user_font_face_set_render_color_glyph_func() may call this
* function to retrieve the current foreground pattern for the glyph
* being rendered. The function should not be called outside of a
* cairo_user_font_face_set_render_color_glyph_func() callback.
*
* The foreground marker pattern contains an internal marker to
* indicate that it is to be substituted with the current source when
* rendered to a surface. Querying the foreground marker will reveal a
* solid black color, however this is not representative of the color
* that will actually be used. Similarly, setting a solid black color
* will render black, not the foreground pattern when the glyph is
* painted to a surface. Using the foreground marker as the source
* instead of cairo_user_scaled_font_get_foreground_source() in a
* color render callback has the following benefits:
*
* 1. Cairo only needs to call the render callback once as it can
* cache the recording. Cairo will substitute the actual foreground
* color when rendering the recording.
*
* 2. On backends that have the concept of a foreground color in fonts such as
* PDF, PostScript, and SVG, cairo can generate more optimal
* output. The glyph can be included in an embedded font.
*
* The one drawback of the using foreground marker is the render
* callback can not access the color components of the pattern as the
* actual foreground pattern is not available at the time the render
* callback is invoked. If the render callback needs to query the
* foreground pattern, use
* cairo_user_scaled_font_get_foreground_source().
*
* If the render callback simply wants to call cairo_set_source() with
* the foreground pattern,
* cairo_user_scaled_font_get_foreground_marker() is the preferred
* function to use as it results in better performance than
* cairo_user_scaled_font_get_foreground_source().
*
* Return value: the current foreground source marker pattern. This
* object is owned by cairo. This object must not be modified or used
* outside of a color render callback. To keep a reference to it,
* you must call cairo_pattern_reference().
*
* Since: 1.18
**/
cairo_pattern_t *
cairo_user_scaled_font_get_foreground_marker (cairo_scaled_font_t *scaled_font)
{
cairo_user_scaled_font_t *user_scaled_font;
if (scaled_font->backend != &_cairo_user_scaled_font_backend)
return _cairo_pattern_create_in_error (CAIRO_STATUS_FONT_TYPE_MISMATCH);
user_scaled_font = (cairo_user_scaled_font_t *)scaled_font;
return user_scaled_font->foreground_marker;
}
/**
* cairo_user_scaled_font_get_foreground_source:
* @scaled_font: A user scaled font
*
* Gets the foreground pattern of the glyph currently being
* rendered. A #cairo_user_scaled_font_render_glyph_func_t function
* that has been set with
* cairo_user_font_face_set_render_color_glyph_func() may call this
* function to retrieve the current foreground pattern for the glyph
* being rendered. The function should not be called outside of a
* cairo_user_font_face_set_render_color_glyph_func() callback.
*
* This function returns the current source at the time the glyph is
* rendered. Compared with
* cairo_user_scaled_font_get_foreground_marker(), this function
* returns the actual source pattern that will be used to render the
* glyph. The render callback is free to query the pattern and
* extract color components or other pattern data. For example if the
* render callback wants to create a gradient stop based on colors in
* the foreground source pattern, it will need to use this function in
* order to be able to query the colors in the foreground pattern.
*
* While this function does not have the restrictions on using the
* pattern that cairo_user_scaled_font_get_foreground_marker() has, it
* does incur a performance penalty. If a render callback calls this
* function:
*
* 1. Cairo will call the render callback whenever the current pattern
* of the context in which the glyph is rendered changes.
*
* 2. On backends that support font embedding (PDF, PostScript, and
* SVG), cairo can not embed this glyph in a font. Instead the glyph
* will be emitted as an image or sequence of drawing operations each
* time it is used.
*
* Return value: the current foreground source pattern. This object is
* owned by cairo. To keep a reference to it, you must call
* cairo_pattern_reference().
*
* Since: 1.18
**/
cairo_pattern_t *
cairo_user_scaled_font_get_foreground_source (cairo_scaled_font_t *scaled_font)
{
cairo_user_scaled_font_t *user_scaled_font;
if (scaled_font->backend != &_cairo_user_scaled_font_backend)
return _cairo_pattern_create_in_error (CAIRO_STATUS_FONT_TYPE_MISMATCH);
user_scaled_font = (cairo_user_scaled_font_t *)scaled_font;
user_scaled_font->foreground_colors_used = TRUE;
return user_scaled_font->foreground_pattern;
}