pangowin32.c

GTK+-2.0源码之pango-1.15.6.tar.gz

  table = g_malloc (ENCODING_TABLE_SIZE*n_tables);

  res = GetFontData (hdc, CMAP, CMAP_HEADER_SIZE, table, ENCODING_TABLE_SIZE*n_tables);
  if (res != ENCODING_TABLE_SIZE*n_tables)
    return 0;

  for (i = 0; i < n_tables; i++)
    {
      if (table[i].platform_id == GUINT16_TO_BE (MICROSOFT_PLATFORM_ID) &&
	  table[i].encoding_id == GUINT16_TO_BE (encoding_id))
	{
	  offset = GUINT32_FROM_BE (table[i].offset);
	  g_free (table);
	  return offset;
	}
    }
  g_free (table);
  return 0;
}

static gpointer
get_format_4_cmap (HDC hdc)
{
  guint32 offset;
  guint32 res;
  guint16 length;
  guint16 *tbl, *tbl_end;
  struct format_4_cmap *table;

  /* FIXME: Could look here at the CRC for the font in the DC
	    and return a cached copy if the same */

  offset = get_cmap_offset (hdc, UNICODE_ENCODING_ID);
  if (offset == 0)
    return NULL;

  res = GetFontData (hdc, CMAP, offset + 2, &length, 2);
  if (res != 2)
    return NULL;
  length = GUINT16_FROM_BE (length);

  table = g_malloc (length);

  res = GetFontData (hdc, CMAP, offset, table, length);
  if (res != length ||
      GUINT16_FROM_BE (table->format) != 4 ||
      (GUINT16_FROM_BE (table->length) % 2) != 0)
    {
      g_free (table);
      return NULL;
    }

  table->format = GUINT16_FROM_BE (table->format);
  table->length = GUINT16_FROM_BE (table->length);
  table->language = GUINT16_FROM_BE (table->language);
  table->seg_count_x_2 = GUINT16_FROM_BE (table->seg_count_x_2);
  table->search_range = GUINT16_FROM_BE (table->search_range);
  table->entry_selector = GUINT16_FROM_BE (table->entry_selector);
  table->range_shift = GUINT16_FROM_BE (table->range_shift);

  tbl_end = (guint16 *)((char *)table + length);
  tbl = &table->reserved;

  while (tbl < tbl_end)
    {
      *tbl = GUINT16_FROM_BE (*tbl);
      tbl++;
    }

  return table;
}

static guint16 *
get_id_range_offset (struct format_4_cmap *table)
{
  gint32 seg_count = table->seg_count_x_2/2;
  return &table->arrays[seg_count*3];
}

static guint16 *
get_id_delta (struct format_4_cmap *table)
{
  gint32 seg_count = table->seg_count_x_2/2;
  return &table->arrays[seg_count*2];
}

static guint16 *
get_start_count (struct format_4_cmap *table)
{
  gint32 seg_count = table->seg_count_x_2/2;
  return &table->arrays[seg_count*1];
}

static guint16 *
get_end_count (struct format_4_cmap *table)
{
  gint32 seg_count = table->seg_count_x_2/2;
  /* Apparently the reseved spot is not reserved for
     the end_count array!? */
  return (&table->arrays[seg_count*0])-1;
}

static gboolean
find_segment (struct format_4_cmap *table,
	      guint16               wc,
	      guint16              *segment)
{
  guint16 start, end, i;
  guint16 seg_count = table->seg_count_x_2/2;
  guint16 *end_count = get_end_count (table);
  guint16 *start_count = get_start_count (table);
  static guint last = 0; /* Cache of one */

  if (last < seg_count &&
      wc >= start_count[last] &&
      wc <= end_count[last])
    {
      *segment = last;
      return TRUE;
    }


  /* Binary search for the segment */
  start = 0; /* inclusive */
  end = seg_count; /* not inclusive */
  while (start < end)
    {
      /* Look at middle pos */
      i = (start + end)/2;

      if (i == start)
	{
	  /* We made no progress. Look if this is the one. */

	  if (wc >= start_count[i] &&
	      wc <= end_count[i])
	    {
	      *segment = i;
	      last = i;
	      return TRUE;
	    }
	  else
	    return FALSE;
	}
      else if (wc < start_count[i])
	{
	  end = i;
	}
      else if (wc > end_count[i])
	{
	  start = i;
	}
      else
	{
	  /* Found it! */
	  *segment = i;
	  last = i;
	  return TRUE;
	}
    }
  return FALSE;
}

static gpointer
get_format_12_cmap (HDC hdc)
{
  guint32 offset;
  guint32 res;
  guint32 length;
  guint32 *tbl, *tbl_end;
  struct format_12_cmap *table;

  offset = get_cmap_offset (hdc, UCS4_ENCODING_ID);
  if (offset == 0)
    return NULL;

  res = GetFontData (hdc, CMAP, offset + 4, &length, 4);
  if (res != 4)
    return NULL;
  length = GUINT32_FROM_BE (length);

  table = g_malloc (length);

  res = GetFontData (hdc, CMAP, offset, table, length);
  if (res != length)
    {
      g_free (table);
      return NULL;
    }

  table->format = GUINT16_FROM_BE (table->format);
  table->length = GUINT32_FROM_BE (table->length);
  table->language = GUINT32_FROM_BE (table->language);
  table->count = GUINT32_FROM_BE (table->count);

  if (table->format != 12 ||
      (table->length % 4) != 0 ||
      table->length > length ||
      table->length < 16 + table->count * 12)
    {
      g_free (table);
      return NULL;
    }

  tbl_end = (guint32 *) ((char *) table + length);
  tbl = table->groups;

  while (tbl < tbl_end)
    {
      *tbl = GUINT32_FROM_BE (*tbl);
      tbl++;
    }

  return table;
}

static gpointer
font_get_cmap (PangoFont *font)
{
  PangoWin32Font *win32font = (PangoWin32Font *)font;
  gpointer cmap;

  if (win32font->win32face->cmap)
    return win32font->win32face->cmap;

  pango_win32_font_select_font (font, pango_win32_hdc);

  /* Prefer the format 12 cmap */
  if ((cmap = get_format_12_cmap (pango_win32_hdc)) != NULL)
    {
      win32font->win32face->cmap_format = 12;
      win32font->win32face->cmap = cmap;
    }
  else if ((cmap = get_format_4_cmap (pango_win32_hdc)) != NULL)
    {
      win32font->win32face->cmap_format = 4;
      win32font->win32face->cmap = cmap;
    }

  pango_win32_font_done_font (font);

  return cmap;
}

/**
 * pango_win32_font_get_glyph_index:
 * @font: a #PangoFont.
 * @wc: a Unicode character.
 *
 * Obtains the index of the glyph for @wc in @font, or 0, if not
 * covered.
 *
 * Return value: the glyph index for @wc.
 **/
gint
pango_win32_font_get_glyph_index (PangoFont *font,
				  gunichar   wc)
{
  PangoWin32Font *win32font = (PangoWin32Font *)font;
  gpointer cmap;
  guint16 glyph;

  /* Do GetFontData magic on font->hfont here. */
  cmap = font_get_cmap (font);

  if (cmap == NULL)
    return 0;

  if (win32font->win32face->cmap_format == 4)
    {
      struct format_4_cmap *cmap4 = cmap;
      guint16 *id_range_offset;
      guint16 *id_delta;
      guint16 *start_count;
      guint16 segment;
      guint16 id;
      guint16 ch = wc;

      if (wc > 0xFFFF)
	return 0;

      if (!find_segment (cmap4, ch, &segment))
	return 0;

      id_range_offset = get_id_range_offset (cmap4);
      id_delta = get_id_delta (cmap4);
      start_count = get_start_count (cmap4);

      if (id_range_offset[segment] == 0)
	glyph = (id_delta[segment] + ch) % 65536;
      else
	{
	  id = *(id_range_offset[segment]/2 +
		 (ch - start_count[segment]) +
		 &id_range_offset[segment]);
	  if (id)
	    glyph = (id_delta[segment] + id) %65536;
	  else
	    glyph = 0;
	}
    }
  else if (win32font->win32face->cmap_format == 12)
    {
      struct format_12_cmap *cmap12 = cmap;
      guint32 i;

      glyph = 0;
      for (i = 0; i < cmap12->count; i++)
	{
	  if (cmap12->groups[i*3+0] <= wc && wc <= cmap12->groups[i*3+1])
	    {
	      glyph = cmap12->groups[i*3+2] + (wc - cmap12->groups[i*3+0]);
	      break;
	    }
	}
    }
  else
    g_assert_not_reached ();

  return glyph;
}

gboolean
pango_win32_get_name_header (HDC                 hdc,
			     struct name_header *header)
{
  if (GetFontData (hdc, NAME, 0, header, sizeof (*header)) != sizeof (*header))
    return FALSE;

  header->num_records = GUINT16_FROM_BE (header->num_records);
  header->string_storage_offset = GUINT16_FROM_BE (header->string_storage_offset);

  return TRUE;
}

gboolean
pango_win32_get_name_record (HDC                 hdc,
			     gint                i,
			     struct name_record *record)
{
  if (GetFontData (hdc, NAME, 6 + i * sizeof (*record),
		   record, sizeof (*record)) != sizeof (*record))
    return FALSE;

  record->platform_id = GUINT16_FROM_BE (record->platform_id);
  record->encoding_id = GUINT16_FROM_BE (record->encoding_id);
  record->language_id = GUINT16_FROM_BE (record->language_id);
  record->name_id = GUINT16_FROM_BE (record->name_id);
  record->string_length = GUINT16_FROM_BE (record->string_length);
  record->string_offset = GUINT16_FROM_BE (record->string_offset);

  return TRUE;
}

static gboolean
font_has_name_in (PangoFont                       *font,
		  PangoWin32CoverageLanguageClass  cjkv)
{
  HFONT hfont, oldhfont;
  struct name_header header;
  struct name_record record;
  gint i;
  gboolean retval = FALSE;

  if (cjkv == PANGO_WIN32_COVERAGE_UNSPEC)
    return TRUE;

  hfont = pango_win32_get_hfont (font);
  oldhfont = SelectObject (pango_win32_hdc, hfont);

  if (!pango_win32_get_name_header (pango_win32_hdc, &header))
    {
      SelectObject (pango_win32_hdc, oldhfont);
      return FALSE;
    }

  for (i = 0; i < header.num_records; i++)
    {
      if (!pango_win32_get_name_record (pango_win32_hdc, i, &record))
	{
	  SelectObject (pango_win32_hdc, oldhfont);
	  return FALSE;
	}

      if ((record.name_id != 1 && record.name_id != 16) || record.string_length <= 0)
	continue;

      PING(("platform:%d encoding:%d language:%04x name_id:%d",
	    record.platform_id, record.encoding_id, record.language_id, record.name_id));

      if (record.platform_id == MICROSOFT_PLATFORM_ID)
	if ((cjkv == PANGO_WIN32_COVERAGE_ZH_TW &&
	     record.language_id == MAKELANGID (LANG_CHINESE, SUBLANG_CHINESE_TRADITIONAL))
	    ||
	    (cjkv == PANGO_WIN32_COVERAGE_ZH_CN &&
	     record.language_id == MAKELANGID (LANG_CHINESE, SUBLANG_CHINESE_SIMPLIFIED))
	    ||
	    (cjkv == PANGO_WIN32_COVERAGE_JA &&
	     PRIMARYLANGID (record.language_id) == LANG_JAPANESE)
	    ||
	    (cjkv == PANGO_WIN32_COVERAGE_KO &&
	     PRIMARYLANGID (record.language_id) == LANG_KOREAN)
	    ||
	    (cjkv == PANGO_WIN32_COVERAGE_VI &&
	     PRIMARYLANGID (record.language_id) == LANG_VIETNAMESE))
	  {
	    PING (("yep:%d:%04x", cjkv, record.language_id));
	    retval = TRUE;
	    break;
	  }
    }

  SelectObject (pango_win32_hdc, oldhfont);
  return retval;
}

static void
pango_win32_font_calc_coverage (PangoFont     *font,
				PangoCoverage *coverage,
				PangoLanguage *lang)
{
  PangoWin32Font *win32font = (PangoWin32Font *)font;
  gpointer cmap;
  guint32 ch;
  guint32 i;
  PangoWin32CoverageLanguageClass cjkv;
  gboolean hide_unihan = FALSE;

  PING(("font:%s lang:%s",
	pango_font_description_to_string (pango_font_describe (font)),
	pango_language_to_string (lang)));

  cjkv = pango_win32_coverage_language_classify (lang);

  if (cjkv != PANGO_WIN32_COVERAGE_UNSPEC && !font_has_name_in (font, cjkv))
    {
      PING(("hiding UniHan chars"));
      hide_unihan = TRUE;
    }

  /* Do GetFontData magic on font->hfont here. */
  cmap = font_get_cmap (font);
  if (cmap == NULL)
    {
      PING(("no table"));
      return;
    }

  PING (("coverage:"));
  if (win32font->win32face->cmap_format == 4)
    {
      struct format_4_cmap *cmap4 = cmap;
      guint16 *id_range_offset;
      guint16 *start_count;
      guint16 *end_count;
      guint16 seg_count;
      guint16 id;

      seg_count = cmap4->seg_count_x_2/2;
      end_count = get_end_count (cmap4);
      start_count = get_start_count (cmap4);
      id_range_offset = get_id_range_offset (cmap4);

      for (i = 0; i < seg_count; i++)
	{
	  if (id_range_offset[i] == 0)
	    {
#ifdef PANGO_WIN32_DEBUGGING
	      if (pango_win32_debug)
		{
		  if (end_count[i] == start_count[i])
		    g_print ("%04x ", start_count[i]);
		  else
		    g_print ("%04x:%04x ", start_count[i], end_count[i]);
		}
#endif
	      for (ch = start_count[i]; ch <= end_count[i]; ch++)
		if (hide_unihan && CH_IS_UNIHAN_BMP (ch))
		  pango_coverage_set (coverage, ch, PANGO_COVERAGE_APPROXIMATE);
		else
		  pango_coverage_set (coverage, ch, PANGO_COVERAGE_EXACT);
	    }
	  else
	    {
#ifdef PANGO_WIN32_DEBUGGING
	      guint32 ch0 = G_MAXUINT;
#endif
	      for (ch = start_count[i]; ch <= end_count[i]; ch++)
		{
		  if (ch == 0xFFFF)
		    break;

		  id = *(id_range_offset[i]/2 +
			 (ch - start_count[i]) +
			 &id_range_offset[i]);
		  if (id)
		    {
#ifdef PANGO_WIN32_DEBUGGING
		      if (ch0 == G_MAXUINT)
			ch0 = ch;
#endif
		      if (hide_unihan && CH_IS_UNIHAN_BMP (ch))
			pango_coverage_set (coverage, ch, PANGO_COVERAGE_APPROXIMATE);
		      else
			pango_coverage_set (coverage, ch, PANGO_COVERAGE_EXACT);
		    }
#ifdef PANGO_WIN32_DEBUGGING
		  else if (ch0 < G_MAXUINT)
		    {
		      if (pango_win32_debug)
			{
			  if (ch > ch0 + 2)
			    g_print ("%04x:%04x ", ch0, ch - 1);
			  else
			    g_print ("%04x ", ch0);
			}
		      ch0 = G_MAXUINT;
		    }
#endif
		}
#ifdef PANGO_WIN32_DEBUGGING
	      if (ch0 < G_MAXUINT)
		{
		  if (pango_win32_debug)
		    {
		      if (ch > ch0 + 2)
			g_print ("%04x:%04x ", ch0, ch - 1);
		      else
			g_print ("%04x ", ch0);
		    }
		}
#endif
	    }
	}
    }
  else if (win32font->win32face->cmap_format == 12)
    {
      struct format_12_cmap *cmap12 = cmap;

      for (i = 0; i < cmap12->count; i++)
	{
#ifdef PANGO_WIN32_DEBUGGING
	  if (pango_win32_debug)
	    {
	      if (cmap12->groups[i*3+0] == cmap12->groups[i*3+1])
		g_print ("%04x ", cmap12->groups[i*3+0]);
	      else
		g_print ("%04x:%04x ", cmap12->groups[i*3+0], cmap12->groups[i*3+1]);
	    }
#endif
	  for (ch = cmap12->groups[i*3+0]; ch <= cmap12->groups[i*3+1]; ch++)
	    {
	      if (hide_unihan && CH_IS_UNIHAN (ch))
		pango_coverage_set (coverage, ch, PANGO_COVERAGE_APPROXIMATE);
	      else
		pango_coverage_set (coverage, ch, PANGO_COVERAGE_EXACT);
	    }
	}
    }
  else
    g_assert_not_reached ();
#ifdef PANGO_WIN32_DEBUGGING
  if (pango_win32_debug)
    g_print ("\n");
#endif
}