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/* cairo - a vector graphics library with display and print output
*
* Copyright © 2005 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 University of Southern
* California.
*
* Contributor(s):
* Owen Taylor <otaylor@redhat.com>
*/
#include "cairoint.h"
#include "cairo-error-private.h"
/**
* SECTION:cairo-font-options
* @Title: cairo_font_options_t
* @Short_Description: How a font should be rendered
* @See_Also: #cairo_scaled_font_t
*
* The font options specify how fonts should be rendered. Most of the
* time the font options implied by a surface are just right and do not
* need any changes, but for pixel-based targets tweaking font options
* may result in superior output on a particular display.
**/
static const cairo_font_options_t _cairo_font_options_nil = {
CAIRO_ANTIALIAS_DEFAULT,
CAIRO_SUBPIXEL_ORDER_DEFAULT,
CAIRO_LCD_FILTER_DEFAULT,
CAIRO_HINT_STYLE_DEFAULT,
CAIRO_HINT_METRICS_DEFAULT,
CAIRO_ROUND_GLYPH_POS_DEFAULT,
NULL
};
/**
* _cairo_font_options_init_default:
* @options: a #cairo_font_options_t
*
* Initializes all fields of the font options object to default values.
**/
void
_cairo_font_options_init_default (cairo_font_options_t *options)
{
options->antialias = CAIRO_ANTIALIAS_DEFAULT;
options->subpixel_order = CAIRO_SUBPIXEL_ORDER_DEFAULT;
options->lcd_filter = CAIRO_LCD_FILTER_DEFAULT;
options->hint_style = CAIRO_HINT_STYLE_DEFAULT;
options->hint_metrics = CAIRO_HINT_METRICS_DEFAULT;
options->round_glyph_positions = CAIRO_ROUND_GLYPH_POS_DEFAULT;
options->variations = NULL;
}
void
_cairo_font_options_init_copy (cairo_font_options_t *options,
const cairo_font_options_t *other)
{
options->antialias = other->antialias;
options->subpixel_order = other->subpixel_order;
options->lcd_filter = other->lcd_filter;
options->hint_style = other->hint_style;
options->hint_metrics = other->hint_metrics;
options->round_glyph_positions = other->round_glyph_positions;
options->variations = other->variations ? strdup (other->variations) : NULL;
}
/**
* cairo_font_options_create:
*
* Allocates a new font options object with all options initialized
* to default values.
*
* Return value: a newly allocated #cairo_font_options_t. Free with
* cairo_font_options_destroy(). This function always returns a
* valid pointer; if memory cannot be allocated, then a special
* error object is returned where all operations on the object do nothing.
* You can check for this with cairo_font_options_status().
*
* Since: 1.0
**/
cairo_font_options_t *
cairo_font_options_create (void)
{
cairo_font_options_t *options;
options = _cairo_malloc (sizeof (cairo_font_options_t));
if (!options) {
_cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
return (cairo_font_options_t *) &_cairo_font_options_nil;
}
_cairo_font_options_init_default (options);
return options;
}
/**
* cairo_font_options_copy:
* @original: a #cairo_font_options_t
*
* Allocates a new font options object copying the option values from
* @original.
*
* Return value: a newly allocated #cairo_font_options_t. Free with
* cairo_font_options_destroy(). This function always returns a
* valid pointer; if memory cannot be allocated, then a special
* error object is returned where all operations on the object do nothing.
* You can check for this with cairo_font_options_status().
*
* Since: 1.0
**/
cairo_font_options_t *
cairo_font_options_copy (const cairo_font_options_t *original)
{
cairo_font_options_t *options;
if (cairo_font_options_status ((cairo_font_options_t *) original))
return (cairo_font_options_t *) &_cairo_font_options_nil;
options = _cairo_malloc (sizeof (cairo_font_options_t));
if (!options) {
_cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
return (cairo_font_options_t *) &_cairo_font_options_nil;
}
_cairo_font_options_init_copy (options, original);
return options;
}
void
_cairo_font_options_fini (cairo_font_options_t *options)
{
free (options->variations);
}
/**
* cairo_font_options_destroy:
* @options: a #cairo_font_options_t
*
* Destroys a #cairo_font_options_t object created with
* cairo_font_options_create() or cairo_font_options_copy().
*
* Since: 1.0
**/
void
cairo_font_options_destroy (cairo_font_options_t *options)
{
if (cairo_font_options_status (options))
return;
_cairo_font_options_fini (options);
free (options);
}
/**
* cairo_font_options_status:
* @options: a #cairo_font_options_t
*
* Checks whether an error has previously occurred for this
* font options object
*
* Return value: %CAIRO_STATUS_SUCCESS or %CAIRO_STATUS_NO_MEMORY
*
* Since: 1.0
**/
cairo_status_t
cairo_font_options_status (cairo_font_options_t *options)
{
if (options == NULL)
return CAIRO_STATUS_NULL_POINTER;
else if (options == (cairo_font_options_t *) &_cairo_font_options_nil)
return CAIRO_STATUS_NO_MEMORY;
else
return CAIRO_STATUS_SUCCESS;
}
slim_hidden_def (cairo_font_options_status);
/**
* cairo_font_options_merge:
* @options: a #cairo_font_options_t
* @other: another #cairo_font_options_t
*
* Merges non-default options from @other into @options, replacing
* existing values. This operation can be thought of as somewhat
* similar to compositing @other onto @options with the operation
* of %CAIRO_OPERATOR_OVER.
*
* Since: 1.0
**/
void
cairo_font_options_merge (cairo_font_options_t *options,
const cairo_font_options_t *other)
{
if (cairo_font_options_status (options))
return;
if (cairo_font_options_status ((cairo_font_options_t *) other))
return;
if (other->antialias != CAIRO_ANTIALIAS_DEFAULT)
options->antialias = other->antialias;
if (other->subpixel_order != CAIRO_SUBPIXEL_ORDER_DEFAULT)
options->subpixel_order = other->subpixel_order;
if (other->lcd_filter != CAIRO_LCD_FILTER_DEFAULT)
options->lcd_filter = other->lcd_filter;
if (other->hint_style != CAIRO_HINT_STYLE_DEFAULT)
options->hint_style = other->hint_style;
if (other->hint_metrics != CAIRO_HINT_METRICS_DEFAULT)
options->hint_metrics = other->hint_metrics;
if (other->round_glyph_positions != CAIRO_ROUND_GLYPH_POS_DEFAULT)
options->round_glyph_positions = other->round_glyph_positions;
if (other->variations) {
if (options->variations) {
char *p;
/* 'merge' variations by concatenating - later entries win */
p = malloc (strlen (other->variations) + strlen (options->variations) + 2);
p[0] = 0;
strcat (p, options->variations);
strcat (p, ",");
strcat (p, other->variations);
free (options->variations);
options->variations = p;
}
else {
options->variations = strdup (other->variations);
}
}
}
slim_hidden_def (cairo_font_options_merge);
/**
* cairo_font_options_equal:
* @options: a #cairo_font_options_t
* @other: another #cairo_font_options_t
*
* Compares two font options objects for equality.
*
* Return value: %TRUE if all fields of the two font options objects match.
* Note that this function will return %FALSE if either object is in
* error.
*
* Since: 1.0
**/
cairo_bool_t
cairo_font_options_equal (const cairo_font_options_t *options,
const cairo_font_options_t *other)
{
if (cairo_font_options_status ((cairo_font_options_t *) options))
return FALSE;
if (cairo_font_options_status ((cairo_font_options_t *) other))
return FALSE;
if (options == other)
return TRUE;
return (options->antialias == other->antialias &&
options->subpixel_order == other->subpixel_order &&
options->lcd_filter == other->lcd_filter &&
options->hint_style == other->hint_style &&
options->hint_metrics == other->hint_metrics &&
options->round_glyph_positions == other->round_glyph_positions &&
((options->variations == NULL && other->variations == NULL) ||
(options->variations != NULL && other->variations != NULL &&
strcmp (options->variations, other->variations) == 0)));
}
slim_hidden_def (cairo_font_options_equal);
/**
* cairo_font_options_hash:
* @options: a #cairo_font_options_t
*
* Compute a hash for the font options object; this value will
* be useful when storing an object containing a #cairo_font_options_t
* in a hash table.
*
* Return value: the hash value for the font options object.
* The return value can be cast to a 32-bit type if a
* 32-bit hash value is needed.
*
* Since: 1.0
**/
unsigned long
cairo_font_options_hash (const cairo_font_options_t *options)
{
unsigned long hash = 0;
if (cairo_font_options_status ((cairo_font_options_t *) options))
options = &_cairo_font_options_nil; /* force default values */
if (options->variations)
hash = _cairo_string_hash (options->variations, strlen (options->variations));
return ((options->antialias) |
(options->subpixel_order << 4) |
(options->lcd_filter << 8) |
(options->hint_style << 12) |
(options->hint_metrics << 16)) ^ hash;
}
slim_hidden_def (cairo_font_options_hash);
/**
* cairo_font_options_set_antialias:
* @options: a #cairo_font_options_t
* @antialias: the new antialiasing mode
*
* Sets the antialiasing mode for the font options object. This
* specifies the type of antialiasing to do when rendering text.
*
* Since: 1.0
**/
void
cairo_font_options_set_antialias (cairo_font_options_t *options,
cairo_antialias_t antialias)
{
if (cairo_font_options_status (options))
return;
options->antialias = antialias;
}
slim_hidden_def (cairo_font_options_set_antialias);
/**
* cairo_font_options_get_antialias:
* @options: a #cairo_font_options_t
*
* Gets the antialiasing mode for the font options object.
*
* Return value: the antialiasing mode
*
* Since: 1.0
**/
cairo_antialias_t
cairo_font_options_get_antialias (const cairo_font_options_t *options)
{
if (cairo_font_options_status ((cairo_font_options_t *) options))
return CAIRO_ANTIALIAS_DEFAULT;
return options->antialias;
}
/**
* cairo_font_options_set_subpixel_order:
* @options: a #cairo_font_options_t
* @subpixel_order: the new subpixel order
*
* Sets the subpixel order for the font options object. The subpixel
* order specifies the order of color elements within each pixel on
* the display device when rendering with an antialiasing mode of
* %CAIRO_ANTIALIAS_SUBPIXEL. See the documentation for
* #cairo_subpixel_order_t for full details.
*
* Since: 1.0
**/
void
cairo_font_options_set_subpixel_order (cairo_font_options_t *options,
cairo_subpixel_order_t subpixel_order)
{
if (cairo_font_options_status (options))
return;
options->subpixel_order = subpixel_order;
}
slim_hidden_def (cairo_font_options_set_subpixel_order);
/**
* cairo_font_options_get_subpixel_order:
* @options: a #cairo_font_options_t
*
* Gets the subpixel order for the font options object.
* See the documentation for #cairo_subpixel_order_t for full details.
*
* Return value: the subpixel order for the font options object
*
* Since: 1.0
**/
cairo_subpixel_order_t
cairo_font_options_get_subpixel_order (const cairo_font_options_t *options)
{
if (cairo_font_options_status ((cairo_font_options_t *) options))
return CAIRO_SUBPIXEL_ORDER_DEFAULT;
return options->subpixel_order;
}
/**
* cairo_font_options_set_lcd_filter:
* @options: a #cairo_font_options_t
* @lcd_filter: the new LCD filter
*
* Sets the LCD filter for the font options object. The LCD filter
* specifies how pixels are filtered when rendered with an antialiasing
* mode of %CAIRO_ANTIALIAS_SUBPIXEL. See the documentation for
* #cairo_lcd_filter_t for full details.
**/
void
cairo_font_options_set_lcd_filter (cairo_font_options_t *options,
cairo_lcd_filter_t lcd_filter)
{
if (cairo_font_options_status (options))
return;
options->lcd_filter = lcd_filter;
}
/**
* cairo_font_options_get_lcd_filter:
* @options: a #cairo_font_options_t
*
* Gets the LCD filter for the font options object.
* See the documentation for #cairo_lcd_filter_t for full details.
*
* Return value: the LCD filter for the font options object
**/
cairo_lcd_filter_t
cairo_font_options_get_lcd_filter (const cairo_font_options_t *options)
{
if (cairo_font_options_status ((cairo_font_options_t *) options))
return CAIRO_LCD_FILTER_DEFAULT;
return options->lcd_filter;
}
/**
* _cairo_font_options_set_round_glyph_positions:
* @options: a #cairo_font_options_t
* @round: the new rounding value
*
* Sets the rounding options for the font options object. If rounding is set, a
* glyph's position will be rounded to integer values.
**/
void
_cairo_font_options_set_round_glyph_positions (cairo_font_options_t *options,
cairo_round_glyph_positions_t round)
{
if (cairo_font_options_status (options))
return;
options->round_glyph_positions = round;
}
/**
* _cairo_font_options_get_round_glyph_positions:
* @options: a #cairo_font_options_t
*
* Gets the glyph position rounding option for the font options object.
*
* Return value: The round glyph posistions flag for the font options object.
**/
cairo_round_glyph_positions_t
_cairo_font_options_get_round_glyph_positions (const cairo_font_options_t *options)
{
if (cairo_font_options_status ((cairo_font_options_t *) options))
return CAIRO_ROUND_GLYPH_POS_DEFAULT;
return options->round_glyph_positions;
}
/**
* cairo_font_options_set_hint_style:
* @options: a #cairo_font_options_t
* @hint_style: the new hint style
*
* Sets the hint style for font outlines for the font options object.
* This controls whether to fit font outlines to the pixel grid,
* and if so, whether to optimize for fidelity or contrast.
* See the documentation for #cairo_hint_style_t for full details.
*
* Since: 1.0
**/
void
cairo_font_options_set_hint_style (cairo_font_options_t *options,
cairo_hint_style_t hint_style)
{
if (cairo_font_options_status (options))
return;
options->hint_style = hint_style;
}
slim_hidden_def (cairo_font_options_set_hint_style);
/**
* cairo_font_options_get_hint_style:
* @options: a #cairo_font_options_t
*
* Gets the hint style for font outlines for the font options object.
* See the documentation for #cairo_hint_style_t for full details.
*
* Return value: the hint style for the font options object
*
* Since: 1.0
**/
cairo_hint_style_t
cairo_font_options_get_hint_style (const cairo_font_options_t *options)
{
if (cairo_font_options_status ((cairo_font_options_t *) options))
return CAIRO_HINT_STYLE_DEFAULT;
return options->hint_style;
}
/**
* cairo_font_options_set_hint_metrics:
* @options: a #cairo_font_options_t
* @hint_metrics: the new metrics hinting mode
*
* Sets the metrics hinting mode for the font options object. This
* controls whether metrics are quantized to integer values in
* device units.
* See the documentation for #cairo_hint_metrics_t for full details.
*
* Since: 1.0
**/
void
cairo_font_options_set_hint_metrics (cairo_font_options_t *options,
cairo_hint_metrics_t hint_metrics)
{
if (cairo_font_options_status (options))
return;
options->hint_metrics = hint_metrics;
}
slim_hidden_def (cairo_font_options_set_hint_metrics);
/**
* cairo_font_options_get_hint_metrics:
* @options: a #cairo_font_options_t
*
* Gets the metrics hinting mode for the font options object.
* See the documentation for #cairo_hint_metrics_t for full details.
*
* Return value: the metrics hinting mode for the font options object
*
* Since: 1.0
**/
cairo_hint_metrics_t
cairo_font_options_get_hint_metrics (const cairo_font_options_t *options)
{
if (cairo_font_options_status ((cairo_font_options_t *) options))
return CAIRO_HINT_METRICS_DEFAULT;
return options->hint_metrics;
}
/**
* cairo_font_options_set_variations:
* @options: a #cairo_font_options_t
* @variations: the new font variations, or %NULL
*
* Sets the OpenType font variations for the font options object.
* Font variations are specified as a string with a format that
* is similar to the CSS font-variation-settings. The string contains
* a comma-separated list of axis assignments, which each assignment
* consists of a 4-character axis name and a value, separated by
* whitespace and optional equals sign.
*
* Examples:
*
* wght=200,wdth=140.5
*
* wght 200 , wdth 140.5
*
* Since: 1.16
**/
void
cairo_font_options_set_variations (cairo_font_options_t *options,
const char *variations)
{
char *tmp = variations ? strdup (variations) : NULL;
free (options->variations);
options->variations = tmp;
}
/**
* cairo_font_options_get_variations:
* @options: a #cairo_font_options_t
*
* Gets the OpenType font variations for the font options object.
* See cairo_font_options_set_variations() for details about the
* string format.
*
* Return value: the font variations for the font options object. The
* returned string belongs to the @options and must not be modified.
* It is valid until either the font options object is destroyed or
* the font variations in this object is modified with
* cairo_font_options_set_variations().
*
* Since: 1.16
**/
const char *
cairo_font_options_get_variations (cairo_font_options_t *options)
{
return options->variations;
}