pangofc-font.c

GTK+-2.0源码之pango-1.15.6.tar.gz

  return metrics;
}

/* This function is cut-and-pasted into pangocairo-fcfont.c - it might be
 * better to add a virtual fcfont->create_context (font).
 */
static PangoFontMetrics *
pango_fc_font_get_metrics (PangoFont     *font,
			   PangoLanguage *language)
{
  PangoFcFont *fcfont = PANGO_FC_FONT (font);
  PangoFcMetricsInfo *info = NULL; /* Quiet gcc */
  GSList *tmp_list;

  const char *sample_str = pango_language_get_sample_string (language);

  tmp_list = fcfont->metrics_by_lang;
  while (tmp_list)
    {
      info = tmp_list->data;

      if (info->sample_str == sample_str)    /* We _don't_ need strcmp */
	break;

      tmp_list = tmp_list->next;
    }

  if (!tmp_list)
    {
      PangoContext *context;

      if (!fcfont->fontmap)
	return pango_font_metrics_new ();

      info = g_slice_new0 (PangoFcMetricsInfo);

      fcfont->metrics_by_lang = g_slist_prepend (fcfont->metrics_by_lang,
						 info);

      info->sample_str = sample_str;

      context = pango_fc_font_map_create_context (PANGO_FC_FONT_MAP (fcfont->fontmap));
      pango_context_set_language (context, language);

      info->metrics = pango_fc_font_create_metrics_for_context (fcfont, context);

      g_object_unref (context);
    }

  return pango_font_metrics_ref (info->metrics);
}

static PangoFontMap *
pango_fc_font_get_font_map (PangoFont *font)
{
  PangoFcFont *fcfont = PANGO_FC_FONT (font);

  return fcfont->fontmap;
}

static gboolean
pango_fc_font_real_has_char (PangoFcFont *font,
			     gunichar     wc)
{
  FcCharSet *charset;

  if (FcPatternGetCharSet (font->font_pattern,
			   FC_CHARSET, 0, &charset) != FcResultMatch)
    return FALSE;

  return FcCharSetHasChar (charset, wc);
}

static guint
pango_fc_font_real_get_glyph (PangoFcFont *font,
			      gunichar     wc)
{
  FT_Face face;
  FT_UInt index;

  guint idx;
  GUnicharToGlyphCacheEntry *entry;

  PangoFcFontPrivate *priv = font->priv;

  if (G_UNLIKELY (priv->char_to_glyph_cache == NULL))
    {
      priv->char_to_glyph_cache = g_new0 (GUnicharToGlyphCacheEntry, GLYPH_CACHE_NUM_ENTRIES);
      /* Make sure all cache entries are invalid initially */
      priv->char_to_glyph_cache[0].ch = 1; /* char 1 cannot happen in bucket 0 */
    }

  idx = wc & GLYPH_CACHE_MASK;
  entry = priv->char_to_glyph_cache + idx;

  if (entry->ch != wc)
    {
      face = PANGO_FC_FONT_LOCK_FACE (font);
      index = FcFreeTypeCharIndex (face, wc);
      if (index > (FT_UInt)face->num_glyphs)
	index = 0;

      entry->ch = wc;
      entry->glyph = index;

      PANGO_FC_FONT_UNLOCK_FACE (font);
    }

  return entry->glyph;
}

/**
 * pango_fc_font_lock_face:
 * @font: a #PangoFcFont.
 *
 * Gets the FreeType <type>FT_Face</type> associated with a font,
 * This face will be kept around until you call
 * pango_fc_font_unlock_face().
 *
 * Return value: the FreeType <type>FT_Face</type> associated with @font.
 *
 * Since: 1.4
 **/
FT_Face
pango_fc_font_lock_face (PangoFcFont *font)
{
  g_return_val_if_fail (PANGO_IS_FC_FONT (font), NULL);

  return PANGO_FC_FONT_LOCK_FACE (font);
}

/**
 * pango_fc_font_unlock_face:
 * @font: a #PangoFcFont.
 *
 * Releases a font previously obtained with
 * pango_fc_font_lock_face().
 *
 * Since: 1.4
 **/
void
pango_fc_font_unlock_face (PangoFcFont *font)
{
  g_return_if_fail (PANGO_IS_FC_FONT (font));

  PANGO_FC_FONT_UNLOCK_FACE (font);
}

/**
 * pango_fc_font_has_char:
 * @font: a #PangoFcFont
 * @wc: Unicode codepoint to look up
 *
 * Determines whether @font has a glyph for the codepoint @wc.
 *
 * Return value: %TRUE if @font has the requested codepoint.
 *
 * Since: 1.4
 **/
gboolean
pango_fc_font_has_char (PangoFcFont *font,
			gunichar     wc)
{
  PangoFcFontPrivate *priv = font->priv;
  FcCharSet *charset;

  g_return_val_if_fail (PANGO_IS_FC_FONT (font), FALSE);

  if (priv->decoder)
    {
      charset = pango_fc_decoder_get_charset (priv->decoder, font);
      return FcCharSetHasChar (charset, wc);
    }

  return PANGO_FC_FONT_GET_CLASS (font)->has_char (font, wc);
}

/**
 * pango_fc_font_get_glyph:
 * @font: a #PangoFcFont
 * @wc: Unicode character to look up
 *
 * Gets the glyph index for a given Unicode character
 * for @font. If you only want to determine
 * whether the font has the glyph, use pango_fc_font_has_char().
 *
 * Return value: the glyph index, or 0, if the Unicode
 *   character doesn't exist in the font.
 *
 * Since: 1.4
 **/
PangoGlyph
pango_fc_font_get_glyph (PangoFcFont *font,
			 gunichar     wc)
{
  PangoFcFontPrivate *priv = font->priv;

  /* Replace NBSP with a normal space; it should be invariant that
   * they shape the same other than breaking properties.
   */
  if (wc == 0xA0)
	  wc = 0x20;

  if (priv->decoder)
    return pango_fc_decoder_get_glyph (priv->decoder, font, wc);

  return PANGO_FC_FONT_GET_CLASS (font)->get_glyph (font, wc);
}


/**
 * pango_fc_font_get_unknown_glyph:
 * @font: a #PangoFcFont
 * @wc: the Unicode character for which a glyph is needed.
 *
 * Returns the index of a glyph suitable for drawing @wc as an
 * unknown character.
 *
 * Use PANGO_GET_UNKNOWN_GLYPH() instead.
 *
 * Return value: a glyph index into @font.
 *
 * Since: 1.4
 **/
PangoGlyph
pango_fc_font_get_unknown_glyph (PangoFcFont *font,
				 gunichar     wc)
{
  if (font && PANGO_FC_FONT_GET_CLASS (font)->get_unknown_glyph)
    return PANGO_FC_FONT_GET_CLASS (font)->get_unknown_glyph (font, wc);

  return PANGO_GET_UNKNOWN_GLYPH (wc);
}

void
_pango_fc_font_shutdown (PangoFcFont *font)
{
  g_return_if_fail (PANGO_IS_FC_FONT (font));

  if (PANGO_FC_FONT_GET_CLASS (font)->shutdown)
    PANGO_FC_FONT_GET_CLASS (font)->shutdown (font);
}

/**
 * pango_fc_font_kern_glyphs
 * @font: a #PangoFcFont
 * @glyphs: a #PangoGlyphString
 *
 * Adjust each adjacent pair of glyphs in @glyphs according to
 * kerning information in @font.
 *
 * Since: 1.4
 **/
void
pango_fc_font_kern_glyphs (PangoFcFont      *font,
			   PangoGlyphString *glyphs)
{
  FT_Face face;
  FT_Error error;
  FT_Vector kerning;
  int i;

  g_return_if_fail (PANGO_IS_FC_FONT (font));
  g_return_if_fail (glyphs != NULL);

  face = PANGO_FC_FONT_LOCK_FACE (font);
  if (!face)
    return;

  if (!FT_HAS_KERNING (face))
    {
      PANGO_FC_FONT_UNLOCK_FACE (font);
      return;
    }

  for (i = 1; i < glyphs->num_glyphs; ++i)
    {
      error = FT_Get_Kerning (face,
			      glyphs->glyphs[i-1].glyph,
			      glyphs->glyphs[i].glyph,
			      ft_kerning_default,
			      &kerning);

      if (error == FT_Err_Ok)
	glyphs->glyphs[i-1].geometry.width += PANGO_UNITS_26_6 (kerning.x);
    }

  PANGO_FC_FONT_UNLOCK_FACE (font);
}

/**
 * _pango_fc_font_get_decoder
 * @font: a #PangoFcFont
 *
 * This will return any custom decoder set on this font.
 *
 * Return value: The custom decoder
 *
 * Since: 1.6
 **/

PangoFcDecoder *
_pango_fc_font_get_decoder (PangoFcFont *font)
{
  PangoFcFontPrivate *priv = font->priv;

  return priv->decoder;
}

/**
 * _pango_fc_font_set_decoder
 * @font: a #PangoFcFont
 * @decoder: a #PangoFcDecoder to set for this font
 *
 * This sets a custom decoder for this font.  Any previous decoder
 * will be released before this one is set.
 *
 * Since: 1.6
 **/

void
_pango_fc_font_set_decoder (PangoFcFont    *font,
			    PangoFcDecoder *decoder)
{
  PangoFcFontPrivate *priv = font->priv;

  if (priv->decoder)
    g_object_unref (priv->decoder);

  priv->decoder = decoder;

  if (priv->decoder)
    g_object_ref (priv->decoder);
}

gpointer
_pango_fc_font_get_context_key (PangoFcFont *fcfont)
{
  PangoFcFontPrivate *priv = fcfont->priv;

  return priv->context_key;
}

void
_pango_fc_font_set_context_key (PangoFcFont *fcfont,
				gpointer     context_key)
{
  PangoFcFontPrivate *priv = fcfont->priv;

  priv->context_key = context_key;
}

static FT_Glyph_Metrics *
get_per_char (FT_Face      face,
	      FT_Int32     load_flags,
	      PangoGlyph   glyph)
{
  FT_Error error;
  FT_Glyph_Metrics *result;

  error = FT_Load_Glyph (face, glyph, load_flags);
  if (error == FT_Err_Ok)
    result = &face->glyph->metrics;
  else
    result = NULL;

  return result;
}

/**
 * pango_fc_font_get_raw_extents:
 * @fcfont: a #PangoFcFont
 * @load_flags: flags to pass to FT_Load_Glyph()
 * @glyph: the glyph index to load
 * @ink_rect: location to store ink extents of the glyph, or %NULL
 * @logical_rect: location to store logical extents of the glyph or %NULL
 *
 * Gets the extents of a single glyph from a font. The extents are in
 * user space; that is, they are not transformed by any matrix in effect
 * for the font.
 *
 * Long term, this functionality probably belongs in the default
 * implementation of the get_glyph_extents() virtual function.
 * The other possibility would be to to make it public in something
 * like it's current form, and also expose glyph information
 * caching functionality similar to pango_ft2_font_set_glyph_info().
 *
 * Since: 1.6
 **/
void
pango_fc_font_get_raw_extents (PangoFcFont    *fcfont,
			       FT_Int32        load_flags,
			       PangoGlyph      glyph,
			       PangoRectangle *ink_rect,
			       PangoRectangle *logical_rect)
{
  FT_Glyph_Metrics *gm;
  FT_Face face;

  g_return_if_fail (PANGO_IS_FC_FONT (fcfont));

  face = PANGO_FC_FONT_LOCK_FACE (fcfont);

  if (glyph == PANGO_GLYPH_EMPTY)
    gm = NULL;
  else
    gm = get_per_char (face, load_flags, glyph);

  if (gm)
    {
      if (ink_rect)
	{
	  ink_rect->x = PANGO_UNITS_26_6 (gm->horiBearingX);
	  ink_rect->width = PANGO_UNITS_26_6 (gm->width);
	  ink_rect->y = -PANGO_UNITS_26_6 (gm->horiBearingY);
	  ink_rect->height = PANGO_UNITS_26_6 (gm->height);
	}

      if (logical_rect)
	{
	  logical_rect->x = 0;
	  logical_rect->width = PANGO_UNITS_26_6 (gm->horiAdvance);
	  if (fcfont->is_hinted ||
	      (face->face_flags & FT_FACE_FLAG_SCALABLE) == 0)
	    {
	      logical_rect->y = - PANGO_UNITS_26_6 (face->size->metrics.ascender);
	      logical_rect->height = PANGO_UNITS_26_6 (face->size->metrics.ascender - face->size->metrics.descender);
	    }
	  else
	    {
	      FT_Fixed ascender, descender;

	      ascender = FT_MulFix (face->ascender, face->size->metrics.y_scale);
	      descender = FT_MulFix (face->descender, face->size->metrics.y_scale);

	      logical_rect->y = - PANGO_UNITS_26_6 (ascender);
	      logical_rect->height = PANGO_UNITS_26_6 (ascender - descender);
	    }
	}
    }
  else
    {
      if (ink_rect)
	{
	  ink_rect->x = 0;
	  ink_rect->width = 0;
	  ink_rect->y = 0;
	  ink_rect->height = 0;
	}

      if (logical_rect)
	{
	  logical_rect->x = 0;
	  logical_rect->width = 0;
	  logical_rect->y = 0;
	  logical_rect->height = 0;
	}
    }

  PANGO_FC_FONT_UNLOCK_FACE (fcfont);
}