util/font-options.hh - third_party/harfbuzz - Git at Google

 /*
  * 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.
  *
  * Google Author(s): Behdad Esfahbod
  */

 #ifndef FONT_OPTIONS_HH
 #define FONT_OPTIONS_HH

 #include "face-options.hh"

 #ifdef HAVE_FREETYPE
 #include <hb-ft.h>
 #endif
 #include <hb-ot.h>

 #define FONT_SIZE_UPEM 0x7FFFFFFF
 #define FONT_SIZE_NONE 0

 extern const unsigned DEFAULT_FONT_SIZE;
 extern const unsigned SUBPIXEL_BITS;

 struct font_options_t : face_options_t
 {
   ~font_options_t ()
   {
     free (variations);
     g_free (font_funcs);
     hb_font_destroy (font);
   }

   void add_options (option_parser_t *parser);

   void post_parse (GError **error);

   hb_variation_t *variations = nullptr;
   unsigned int num_variations = 0;
   int x_ppem = 0;
   int y_ppem = 0;
   double ptem = 0.;
   unsigned int subpixel_bits = SUBPIXEL_BITS;
   mutable double font_size_x = DEFAULT_FONT_SIZE;
   mutable double font_size_y = DEFAULT_FONT_SIZE;
   char *font_funcs = nullptr;
   int ft_load_flags = 2;

   hb_font_t *font = nullptr;
 };


 static struct supported_font_funcs_t {
 	char name[4];
 	void (*func) (hb_font_t *);
 } supported_font_funcs[] =
 {
 #ifdef HAVE_FREETYPE
   {"ft",	hb_ft_font_set_funcs},
 #endif
   {"ot",	hb_ot_font_set_funcs},
 };


 void
 font_options_t::post_parse (GError **error)
 {
   assert (!font);
   font = hb_font_create (face);

   if (font_size_x == FONT_SIZE_UPEM)
     font_size_x = hb_face_get_upem (face);
   if (font_size_y == FONT_SIZE_UPEM)
     font_size_y = hb_face_get_upem (face);

   hb_font_set_ppem (font, x_ppem, y_ppem);
   hb_font_set_ptem (font, ptem);

   int scale_x = (int) scalbnf (font_size_x, subpixel_bits);
   int scale_y = (int) scalbnf (font_size_y, subpixel_bits);
   hb_font_set_scale (font, scale_x, scale_y);

   hb_font_set_variations (font, variations, num_variations);

   void (*set_font_funcs) (hb_font_t *) = nullptr;
   if (!font_funcs)
   {
     set_font_funcs = supported_font_funcs[0].func;
   }
   else
   {
     for (unsigned int i = 0; i < ARRAY_LENGTH (supported_font_funcs); i++)
       if (0 == g_ascii_strcasecmp (font_funcs, supported_font_funcs[i].name))
       {
 	set_font_funcs = supported_font_funcs[i].func;
 	break;
       }
     if (!set_font_funcs)
     {
       GString *s = g_string_new (nullptr);
       for (unsigned int i = 0; i < ARRAY_LENGTH (supported_font_funcs); i++)
       {
 	if (i)
 	  g_string_append_c (s, '/');
 	g_string_append (s, supported_font_funcs[i].name);
       }
       g_string_append_c (s, '\n');
       char *p = g_string_free (s, FALSE);
       g_set_error (error, G_OPTION_ERROR, G_OPTION_ERROR_BAD_VALUE,
 		   "Unknown font function implementation `%s'; supported values are: %s; default is %s",
 		   font_funcs,
 		   p,
 		   supported_font_funcs[0].name);
       free (p);
       return;
     }
   }
   set_font_funcs (font);
 #ifdef HAVE_FREETYPE
   hb_ft_font_set_load_flags (font, ft_load_flags);
 #endif
 }


 static gboolean
 parse_variations (const char *name G_GNUC_UNUSED,
 		  const char *arg,
 		  gpointer    data,
 		  GError    **error G_GNUC_UNUSED)
 {
   font_options_t *font_opts = (font_options_t *) data;
   char *s = (char *) arg;
   char *p;

   font_opts->num_variations = 0;
   g_free (font_opts->variations);
   font_opts->variations = nullptr;

   if (!*s)
     return true;

   /* count the variations first, so we can allocate memory */
   p = s;
   do {
     font_opts->num_variations++;
     p = strchr (p, ',');
     if (p)
       p++;
   } while (p);

   font_opts->variations = (hb_variation_t *) calloc (font_opts->num_variations, sizeof (*font_opts->variations));
   if (!font_opts->variations)
     return false;

   /* now do the actual parsing */
   p = s;
   font_opts->num_variations = 0;
   while (p && *p) {
     char *end = strchr (p, ',');
     if (hb_variation_from_string (p, end ? end - p : -1, &font_opts->variations[font_opts->num_variations]))
       font_opts->num_variations++;
     p = end ? end + 1 : nullptr;
   }

   return true;
 }

 static gboolean
 parse_font_size (const char *name G_GNUC_UNUSED,
 		 const char *arg,
 		 gpointer    data,
 		 GError    **error G_GNUC_UNUSED)
 {
   font_options_t *font_opts = (font_options_t *) data;
   if (0 == strcmp (arg, "upem"))
   {
     font_opts->font_size_y = font_opts->font_size_x = FONT_SIZE_UPEM;
     return true;
   }
   switch (sscanf (arg, "%lf%*[ ,]%lf", &font_opts->font_size_x, &font_opts->font_size_y)) {
     case 1: font_opts->font_size_y = font_opts->font_size_x; HB_FALLTHROUGH;
     case 2: return true;
     default:
       g_set_error (error, G_OPTION_ERROR, G_OPTION_ERROR_BAD_VALUE,
 		   "%s argument should be one or two space-separated numbers",
 		   name);
       return false;
   }
 }

 static gboolean
 parse_font_ppem (const char *name G_GNUC_UNUSED,
 		 const char *arg,
 		 gpointer    data,
 		 GError    **error G_GNUC_UNUSED)
 {
   font_options_t *font_opts = (font_options_t *) data;
   switch (sscanf (arg, "%d%*[ ,]%d", &font_opts->x_ppem, &font_opts->y_ppem)) {
     case 1: font_opts->y_ppem = font_opts->x_ppem; HB_FALLTHROUGH;
     case 2: return true;
     default:
       g_set_error (error, G_OPTION_ERROR, G_OPTION_ERROR_BAD_VALUE,
 		   "%s argument should be one or two space-separated numbers",
 		   name);
       return false;
   }
 }

 void
 font_options_t::add_options (option_parser_t *parser)
 {
   face_options_t::add_options (parser);

   char *text = nullptr;

   {
     static_assert ((ARRAY_LENGTH_CONST (supported_font_funcs) > 0),
 		   "No supported font-funcs found.");
     GString *s = g_string_new (nullptr);
     g_string_printf (s, "Set font functions implementation to use (default: %s)\n\n    Supported font function implementations are: %s",
 		     supported_font_funcs[0].name,
 		     supported_font_funcs[0].name);
     for (unsigned int i = 1; i < ARRAY_LENGTH (supported_font_funcs); i++)
     {
       g_string_append_c (s, '/');
       g_string_append (s, supported_font_funcs[i].name);
     }
     text = g_string_free (s, FALSE);
     parser->free_later (text);
   }

   char *font_size_text;
   if (DEFAULT_FONT_SIZE == FONT_SIZE_UPEM)
     font_size_text = (char *) "Font size (default: upem)";
   else
   {
     font_size_text = g_strdup_printf ("Font size (default: %d)", DEFAULT_FONT_SIZE);
     parser->free_later (font_size_text);
   }

   int font_size_flags = DEFAULT_FONT_SIZE == FONT_SIZE_NONE ? G_OPTION_FLAG_HIDDEN : 0;
   GOptionEntry entries[] =
   {
     {"font-size",	0, font_size_flags,
 			      G_OPTION_ARG_CALLBACK,	(gpointer) &parse_font_size,	font_size_text,					"1/2 integers or 'upem'"},
     {"font-ppem",	0, font_size_flags,
 			      G_OPTION_ARG_CALLBACK,	(gpointer) &parse_font_ppem,	"Set x,y pixels per EM (default: 0; disabled)",	"1/2 integers"},
     {"font-ptem",	0, 0,
 			      G_OPTION_ARG_DOUBLE,	&this->ptem,			"Set font point-size (default: 0; disabled)",	"point-size"},
     {"font-funcs",	0, 0, G_OPTION_ARG_STRING,	&this->font_funcs,		text,						"impl"},
     {"ft-load-flags",	0, 0, G_OPTION_ARG_INT,		&this->ft_load_flags,		"Set FreeType load-flags (default: 2)",		"integer"},
     {nullptr}
   };
   parser->add_group (entries,
 		     "font",
 		     "Font-instance options:",
 		     "Options for the font instance",
 		     this,
 		     false /* We add below. */);

   const gchar *variations_help = "Comma-separated list of font variations\n"
     "\n"
     "    Variations are set globally. The format for specifying variation settings\n"
     "    follows.  All valid CSS font-variation-settings values other than 'normal'\n"
     "    and 'inherited' are also accepted, though, not documented below.\n"
     "\n"
     "    The format is a tag, optionally followed by an equals sign, followed by a\n"
     "    number. For example:\n"
     "\n"
     "      \"wght=500\"\n"
     "      \"slnt=-7.5\"";

   GOptionEntry entries2[] =
   {
     {"variations",	0, 0, G_OPTION_ARG_CALLBACK,	(gpointer) &parse_variations,	variations_help,	"list"},
     {nullptr}
   };
   parser->add_group (entries2,
 		     "variations",
 		     "Variations options:",
 		     "Options for font variations used",
 		     this);
 }

 #endif
	/*
	* 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.
	*
	* Google Author(s): Behdad Esfahbod
	*/

	#ifndef FONT_OPTIONS_HH
	#define FONT_OPTIONS_HH

	#include "face-options.hh"

	#ifdef HAVE_FREETYPE
	#include <hb-ft.h>
	#endif
	#include <hb-ot.h>

	#define FONT_SIZE_UPEM 0x7FFFFFFF
	#define FONT_SIZE_NONE 0

	extern const unsigned DEFAULT_FONT_SIZE;
	extern const unsigned SUBPIXEL_BITS;

	struct font_options_t : face_options_t
	{
	~font_options_t ()
	{
	free (variations);
	g_free (font_funcs);
	hb_font_destroy (font);
	}

	void add_options (option_parser_t *parser);

	void post_parse (GError **error);

	hb_variation_t *variations = nullptr;
	unsigned int num_variations = 0;
	int x_ppem = 0;
	int y_ppem = 0;
	double ptem = 0.;
	unsigned int subpixel_bits = SUBPIXEL_BITS;
	mutable double font_size_x = DEFAULT_FONT_SIZE;
	mutable double font_size_y = DEFAULT_FONT_SIZE;
	char *font_funcs = nullptr;
	int ft_load_flags = 2;

	hb_font_t *font = nullptr;
	};


	static struct supported_font_funcs_t {
	char name[4];
	void (func) (hb_font_t );
	} supported_font_funcs[] =
	{
	#ifdef HAVE_FREETYPE
	{"ft", hb_ft_font_set_funcs},
	#endif
	{"ot", hb_ot_font_set_funcs},
	};


	void
	font_options_t::post_parse (GError **error)
	{
	assert (!font);
	font = hb_font_create (face);

	if (font_size_x == FONT_SIZE_UPEM)
	font_size_x = hb_face_get_upem (face);
	if (font_size_y == FONT_SIZE_UPEM)
	font_size_y = hb_face_get_upem (face);

	hb_font_set_ppem (font, x_ppem, y_ppem);
	hb_font_set_ptem (font, ptem);

	int scale_x = (int) scalbnf (font_size_x, subpixel_bits);
	int scale_y = (int) scalbnf (font_size_y, subpixel_bits);
	hb_font_set_scale (font, scale_x, scale_y);

	hb_font_set_variations (font, variations, num_variations);

	void (set_font_funcs) (hb_font_t ) = nullptr;
	if (!font_funcs)
	{
	set_font_funcs = supported_font_funcs[0].func;
	}
	else
	{
	for (unsigned int i = 0; i < ARRAY_LENGTH (supported_font_funcs); i++)
	if (0 == g_ascii_strcasecmp (font_funcs, supported_font_funcs[i].name))
	{
	set_font_funcs = supported_font_funcs[i].func;
	break;
	}
	if (!set_font_funcs)
	{
	GString *s = g_string_new (nullptr);
	for (unsigned int i = 0; i < ARRAY_LENGTH (supported_font_funcs); i++)
	{
	if (i)
	g_string_append_c (s, '/');
	g_string_append (s, supported_font_funcs[i].name);
	}
	g_string_append_c (s, '\n');
	char *p = g_string_free (s, FALSE);
	g_set_error (error, G_OPTION_ERROR, G_OPTION_ERROR_BAD_VALUE,
	"Unknown font function implementation `%s'; supported values are: %s; default is %s",
	font_funcs,
	p,
	supported_font_funcs[0].name);
	free (p);
	return;
	}
	}
	set_font_funcs (font);
	#ifdef HAVE_FREETYPE
	hb_ft_font_set_load_flags (font, ft_load_flags);
	#endif
	}


	static gboolean
	parse_variations (const char *name G_GNUC_UNUSED,
	const char *arg,
	gpointer data,
	GError **error G_GNUC_UNUSED)
	{
	font_options_t font_opts = (font_options_t ) data;
	char s = (char ) arg;
	char *p;

	font_opts->num_variations = 0;
	g_free (font_opts->variations);
	font_opts->variations = nullptr;

	if (!*s)
	return true;

	/* count the variations first, so we can allocate memory */
	p = s;
	do {
	font_opts->num_variations++;
	p = strchr (p, ',');
	if (p)
	p++;
	} while (p);

	font_opts->variations = (hb_variation_t ) calloc (font_opts->num_variations, sizeof (font_opts->variations));
	if (!font_opts->variations)
	return false;

	/* now do the actual parsing */
	p = s;
	font_opts->num_variations = 0;
	while (p && *p) {
	char *end = strchr (p, ',');
	if (hb_variation_from_string (p, end ? end - p : -1, &font_opts->variations[font_opts->num_variations]))
	font_opts->num_variations++;
	p = end ? end + 1 : nullptr;
	}

	return true;
	}

	static gboolean
	parse_font_size (const char *name G_GNUC_UNUSED,
	const char *arg,
	gpointer data,
	GError **error G_GNUC_UNUSED)
	{
	font_options_t font_opts = (font_options_t ) data;
	if (0 == strcmp (arg, "upem"))
	{
	font_opts->font_size_y = font_opts->font_size_x = FONT_SIZE_UPEM;
	return true;
	}
	switch (sscanf (arg, "%lf%*[ ,]%lf", &font_opts->font_size_x, &font_opts->font_size_y)) {
	case 1: font_opts->font_size_y = font_opts->font_size_x; HB_FALLTHROUGH;
	case 2: return true;
	default:
	g_set_error (error, G_OPTION_ERROR, G_OPTION_ERROR_BAD_VALUE,
	"%s argument should be one or two space-separated numbers",
	name);
	return false;
	}
	}

	static gboolean
	parse_font_ppem (const char *name G_GNUC_UNUSED,
	const char *arg,
	gpointer data,
	GError **error G_GNUC_UNUSED)
	{
	font_options_t font_opts = (font_options_t ) data;
	switch (sscanf (arg, "%d%*[ ,]%d", &font_opts->x_ppem, &font_opts->y_ppem)) {
	case 1: font_opts->y_ppem = font_opts->x_ppem; HB_FALLTHROUGH;
	case 2: return true;
	default:
	g_set_error (error, G_OPTION_ERROR, G_OPTION_ERROR_BAD_VALUE,
	"%s argument should be one or two space-separated numbers",
	name);
	return false;
	}
	}

	void
	font_options_t::add_options (option_parser_t *parser)
	{
	face_options_t::add_options (parser);

	char *text = nullptr;

	{
	static_assert ((ARRAY_LENGTH_CONST (supported_font_funcs) > 0),
	"No supported font-funcs found.");
	GString *s = g_string_new (nullptr);
	g_string_printf (s, "Set font functions implementation to use (default: %s)\n\n Supported font function implementations are: %s",
	supported_font_funcs[0].name,
	supported_font_funcs[0].name);
	for (unsigned int i = 1; i < ARRAY_LENGTH (supported_font_funcs); i++)
	{
	g_string_append_c (s, '/');
	g_string_append (s, supported_font_funcs[i].name);
	}
	text = g_string_free (s, FALSE);
	parser->free_later (text);
	}

	char *font_size_text;
	if (DEFAULT_FONT_SIZE == FONT_SIZE_UPEM)
	font_size_text = (char *) "Font size (default: upem)";
	else
	{
	font_size_text = g_strdup_printf ("Font size (default: %d)", DEFAULT_FONT_SIZE);
	parser->free_later (font_size_text);
	}

	int font_size_flags = DEFAULT_FONT_SIZE == FONT_SIZE_NONE ? G_OPTION_FLAG_HIDDEN : 0;
	GOptionEntry entries[] =
	{
	{"font-size", 0, font_size_flags,
	G_OPTION_ARG_CALLBACK, (gpointer) &parse_font_size, font_size_text, "1/2 integers or 'upem'"},
	{"font-ppem", 0, font_size_flags,
	G_OPTION_ARG_CALLBACK, (gpointer) &parse_font_ppem, "Set x,y pixels per EM (default: 0; disabled)", "1/2 integers"},
	{"font-ptem", 0, 0,
	G_OPTION_ARG_DOUBLE, &this->ptem, "Set font point-size (default: 0; disabled)", "point-size"},
	{"font-funcs", 0, 0, G_OPTION_ARG_STRING, &this->font_funcs, text, "impl"},
	{"ft-load-flags", 0, 0, G_OPTION_ARG_INT, &this->ft_load_flags, "Set FreeType load-flags (default: 2)", "integer"},
	{nullptr}
	};
	parser->add_group (entries,
	"font",
	"Font-instance options:",
	"Options for the font instance",
	this,
	false /* We add below. */);

	const gchar *variations_help = "Comma-separated list of font variations\n"
	"\n"
	" Variations are set globally. The format for specifying variation settings\n"
	" follows. All valid CSS font-variation-settings values other than 'normal'\n"
	" and 'inherited' are also accepted, though, not documented below.\n"
	"\n"
	" The format is a tag, optionally followed by an equals sign, followed by a\n"
	" number. For example:\n"
	"\n"
	" \"wght=500\"\n"
	" \"slnt=-7.5\"";

	GOptionEntry entries2[] =
	{
	{"variations", 0, 0, G_OPTION_ARG_CALLBACK, (gpointer) &parse_variations, variations_help, "list"},
	{nullptr}
	};
	parser->add_group (entries2,
	"variations",
	"Variations options:",
	"Options for font variations used",
	this);
	}

	#endif