pangoatsui-fontmap.c

Pango is a library for layout and rendering of text, with an emphasis on internationalization. Pang

  return face->synthetic_italic;
}

PangoCoverage *
_pango_atsui_face_get_coverage (PangoATSUIFace *face,
				PangoLanguage  *language)
{
  int i;

  /* Note: We currently fake the coverage by reporting that the 255 first 
   * glyphs exist in all fonts, which is not true. It's unclear how to get
   * this done correctly.
   */

  if (face->coverage)
    return face->coverage;

  face->coverage = pango_coverage_new ();

  for (i = 0; i < 256; i++)
    pango_coverage_set (face->coverage, i, PANGO_COVERAGE_EXACT);

  return face->coverage;
}

static void pango_atsui_font_map_class_init (PangoATSUIFontMapClass *class);
static void pango_atsui_font_map_init (PangoATSUIFontMap *atsuifontmap);

static guint    font_hash_key_hash  (const FontHashKey *key);
static gboolean font_hash_key_equal (const FontHashKey *key_a,
				     const FontHashKey *key_b);
static void     font_hash_key_free  (FontHashKey       *key);

G_DEFINE_TYPE (PangoATSUIFontMap, pango_atsui_font_map, PANGO_TYPE_FONT_MAP);

static void
pango_atsui_font_map_finalize (GObject *object)
{
  PangoATSUIFontMap *fontmap = PANGO_ATSUI_FONT_MAP (object);

  g_hash_table_destroy (fontmap->font_hash);
  g_hash_table_destroy (fontmap->families);

  G_OBJECT_CLASS (pango_atsui_font_map_parent_class)->finalize (object);
}

struct _FontHashKey {
  PangoATSUIFontMap *fontmap;
  PangoMatrix matrix;
  PangoFontDescription *desc;
  char *postscript_name;
  gpointer context_key;
};

/* Fowler / Noll / Vo (FNV) Hash (http://www.isthe.com/chongo/tech/comp/fnv/)
 *
 * Not necessarily better than a lot of other hashes, but should be OK, and
 * well tested with binary data.
 */

#define FNV_32_PRIME ((guint32)0x01000193)
#define FNV1_32_INIT ((guint32)0x811c9dc5)

static guint32
hash_bytes_fnv (unsigned char *buffer,
		int            len,
		guint32        hval)
{
  while (len--)
    {
      hval *= FNV_32_PRIME;
      hval ^= *buffer++;
    }

  return hval;
}

static gboolean
font_hash_key_equal (const FontHashKey *key_a,
		     const FontHashKey *key_b)
{
  if (key_a->matrix.xx == key_b->matrix.xx &&
      key_a->matrix.xy == key_b->matrix.xy &&
      key_a->matrix.yx == key_b->matrix.yx &&
      key_a->matrix.yy == key_b->matrix.yy &&
      pango_font_description_equal (key_a->desc, key_b->desc) &&
      strcmp (key_a->postscript_name, key_b->postscript_name) == 0)
    {
      if (key_a->context_key)
	return PANGO_ATSUI_FONT_MAP_GET_CLASS (key_a->fontmap)->context_key_equal (key_a->fontmap,
										key_a->context_key,
										key_b->context_key);
      else
	return TRUE;
    }
  else
    return FALSE;
}

static guint
font_hash_key_hash (const FontHashKey *key)
{
    guint32 hash = FNV1_32_INIT;

    /* We do a bytewise hash on the context matrix */
    hash = hash_bytes_fnv ((unsigned char *)(&key->matrix),
			   sizeof(double) * 4,
			   hash);

    if (key->context_key)
      hash ^= PANGO_ATSUI_FONT_MAP_GET_CLASS (key->fontmap)->context_key_hash (key->fontmap,
									       key->context_key);

    hash ^= g_str_hash (key->postscript_name);

    return (hash ^ pango_font_description_hash (key->desc));
}

static void
font_hash_key_free (FontHashKey *key)
{
  if (key->context_key)
    PANGO_ATSUI_FONT_MAP_GET_CLASS (key->fontmap)->context_key_free (key->fontmap,
								     key->context_key);

  g_slice_free (FontHashKey, key);
}

static FontHashKey *
font_hash_key_copy (FontHashKey *old)
{
  FontHashKey *key = g_slice_new (FontHashKey);

  key->fontmap = old->fontmap;
  key->matrix = old->matrix;
  key->desc = pango_font_description_copy (old->desc);
  key->postscript_name = g_strdup (old->postscript_name);
  if (old->context_key)
    key->context_key = PANGO_ATSUI_FONT_MAP_GET_CLASS (key->fontmap)->context_key_copy (key->fontmap,
											old->context_key);
  else
    key->context_key = NULL;

  return key;
}


static void
get_context_matrix (PangoContext *context,
		    PangoMatrix *matrix)
{
  const PangoMatrix *set_matrix;
  static const PangoMatrix identity = PANGO_MATRIX_INIT;

  if (context)
    set_matrix = pango_context_get_matrix (context);
  else
    set_matrix = NULL;

  if (set_matrix)
    *matrix = *set_matrix;
  else
    *matrix = identity;
}

static void
font_hash_key_for_context (PangoATSUIFontMap *fcfontmap,
			   PangoContext   *context,
			   FontHashKey    *key)
{
  key->fontmap = fcfontmap;
  get_context_matrix (context, &key->matrix);

  if (PANGO_ATSUI_FONT_MAP_GET_CLASS (fcfontmap)->context_key_get)
    key->context_key = (gpointer)PANGO_ATSUI_FONT_MAP_GET_CLASS (fcfontmap)->context_key_get (fcfontmap, context);
  else
    key->context_key = NULL;
}

static void
pango_atsui_font_map_add (PangoATSUIFontMap *atsuifontmap,
			  PangoContext      *context,
			  PangoATSUIFont    *atsuifont)
{
  FontHashKey key;
  FontHashKey *key_copy;
  PangoATSUIFace *face;

  _pango_atsui_font_set_font_map (atsuifont, atsuifontmap);

  font_hash_key_for_context (atsuifontmap, context, &key);
  face = _pango_atsui_font_get_face (atsuifont);
  key.postscript_name = (char *)_pango_atsui_face_get_postscript_name (face);
  key.desc = _pango_atsui_font_get_font_description (atsuifont);

  key_copy = font_hash_key_copy (&key);
  _pango_atsui_font_set_context_key (atsuifont, key_copy->context_key);
  g_hash_table_insert (atsuifontmap->font_hash, key_copy, g_object_ref (atsuifont));
}

static PangoATSUIFont *
pango_atsui_font_map_lookup (PangoATSUIFontMap    *atsuifontmap,
			     PangoContext         *context,
			     PangoFontDescription *desc,
			     PangoATSUIFace       *face)
{
  FontHashKey key;

  font_hash_key_for_context (atsuifontmap, context, &key);
  key.postscript_name = (char *)_pango_atsui_face_get_postscript_name (face);
  key.desc = desc;

  return g_hash_table_lookup (atsuifontmap->font_hash, &key);
}

static gboolean
find_best_match (PangoATSUIFamily            *font_family,
		 const PangoFontDescription  *description,
		 PangoFontDescription       **best_description,
		 PangoATSUIFace             **best_face)
{
  PangoFontDescription *new_desc;
  int i;

  *best_description = NULL;
  *best_face = NULL;

  for (i = 0; i < font_family->n_faces; i++)
    {
      new_desc = pango_font_face_describe (font_family->faces[i]);

      if (pango_font_description_better_match (description, *best_description, new_desc))
	{
	  pango_font_description_free (*best_description);
	  *best_description = new_desc;
	  *best_face = (PangoATSUIFace *)font_family->faces[i];
	}
      else
	pango_font_description_free (new_desc);
    }

  if (*best_description)
    return TRUE;

  return FALSE;
}

static PangoFont *
pango_atsui_font_map_load_font (PangoFontMap               *fontmap,
				PangoContext               *context,
				const PangoFontDescription *description)
{
  PangoATSUIFontMap *atsuifontmap = (PangoATSUIFontMap *)fontmap;
  PangoATSUIFamily *font_family;
  gchar *name;
  gint size;

  size = pango_font_description_get_size (description);
  if (size < 0)
    return NULL;

  name = g_utf8_casefold (pango_font_description_get_family (description), -1);
  font_family = g_hash_table_lookup (atsuifontmap->families, name);
  g_free (name);

  if (font_family)
    {
      PangoFontDescription *best_description;
      PangoATSUIFace *best_face;
      PangoATSUIFont *best_font;

      /* Force a listing of the available faces */
      pango_font_family_list_faces ((PangoFontFamily *)font_family, NULL, NULL);

      if (!find_best_match (font_family, description, &best_description, &best_face))
	return NULL;
      
      pango_font_description_set_size (best_description, size);

      best_font = pango_atsui_font_map_lookup (atsuifontmap, 
					       context, 
					       best_description, 
					       best_face);

      if (best_font)
	g_object_ref (best_font);
      else
	{
	  PangoATSUIFontMapClass *klass;

	  klass = PANGO_ATSUI_FONT_MAP_GET_CLASS (atsuifontmap);
	  best_font = klass->create_font (atsuifontmap, context, 
					  best_face, best_description);
	  
	  if (best_font)
	    pango_atsui_font_map_add (atsuifontmap, context, best_font);
	    /* TODO: Handle the else case here. */
	}

      pango_font_description_free (best_description);

      return (PangoFont *)best_font;
    }

  return NULL;
}

static void
list_families_foreach (gpointer key,
		       gpointer value,
		       gpointer user_data)
{
  GSList **list = user_data;

  *list = g_slist_prepend (*list, value);
}

static void
pango_atsui_font_map_list_families (PangoFontMap      *fontmap,
				    PangoFontFamily ***families,
				    int               *n_families)
{
  GSList *family_list = NULL;
  GSList *tmp_list;
  PangoATSUIFontMap *atsuifontmap = (PangoATSUIFontMap *)fontmap;

  if (!n_families)
    return;

  g_hash_table_foreach (atsuifontmap->families, list_families_foreach, &family_list);

  *n_families = g_slist_length (family_list);

  if (families)
    {
      int i = 0;

      *families = g_new (PangoFontFamily *, *n_families);

      tmp_list = family_list;
      while (tmp_list)
	{
	  (*families)[i] = tmp_list->data;
	  i++;
	  tmp_list = tmp_list->next;
	}
    }

  g_slist_free (family_list);
}

static void
pango_atsui_font_map_init (PangoATSUIFontMap *atsuifontmap)
{
  NSArray *family_array;
  NSAutoreleasePool *pool;
  PangoATSUIFamily *family;

  int size, i;

  atsuifontmap->families = g_hash_table_new_full (g_str_hash, g_str_equal,
						  g_free, g_object_unref);


  atsuifontmap->font_hash = g_hash_table_new_full ((GHashFunc)font_hash_key_hash,
						   (GEqualFunc)font_hash_key_equal,
						   (GDestroyNotify)font_hash_key_free,
						   NULL);

  pool = [[NSAutoreleasePool alloc] init];
  family_array = [[NSFontManager sharedFontManager] availableFontFamilies];
  size = [family_array count];

  for (i = 0; i < size; i++) {
    NSString *family_name = [family_array objectAtIndex:i];

    family = g_object_new (PANGO_TYPE_ATSUI_FAMILY, NULL);
    family->family_name = g_strdup ([family_name UTF8String]);

    g_hash_table_insert (atsuifontmap->families, g_utf8_casefold (family->family_name, -1), family);
  }

  /* Insert aliases */
  family = g_object_new (PANGO_TYPE_ATSUI_FAMILY, NULL);
  family->family_name = g_strdup ("Sans");
  g_hash_table_insert (atsuifontmap->families, g_utf8_casefold (family->family_name, -1), family);

  family = g_object_new (PANGO_TYPE_ATSUI_FAMILY, NULL);
  family->family_name = g_strdup ("Serif");
  g_hash_table_insert (atsuifontmap->families, g_utf8_casefold (family->family_name, -1), family);

  family = g_object_new (PANGO_TYPE_ATSUI_FAMILY, NULL);
  family->family_name = g_strdup ("Monospace");
  g_hash_table_insert (atsuifontmap->families, g_utf8_casefold (family->family_name, -1), family);

  [pool release];
}

static void
pango_atsui_font_map_class_init (PangoATSUIFontMapClass *class)
{
  GObjectClass *object_class = G_OBJECT_CLASS (class);
  PangoFontMapClass *fontmap_class = PANGO_FONT_MAP_CLASS (class);

  object_class->finalize = pango_atsui_font_map_finalize;

  fontmap_class->load_font = pango_atsui_font_map_load_font;
  fontmap_class->list_families = pango_atsui_font_map_list_families;
  fontmap_class->shape_engine_type = PANGO_RENDER_TYPE_ATSUI;
}