pangowin32.c

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

  if (!coverage)
    {
      coverage = pango_coverage_new ();
      pango_win32_font_calc_coverage (font, coverage, lang);

      pango_win32_font_entry_set_coverage (win32font->win32face, coverage, lang);
    }

  return coverage;
}

static PangoEngineShape *
pango_win32_font_find_shaper (PangoFont     *font,
			      PangoLanguage *lang,
			      guint32        ch)
{
  PangoMap *shape_map = NULL;
  PangoScript script;

  shape_map = pango_win32_get_shaper_map (lang);
  script = pango_script_for_unichar (ch);
  return (PangoEngineShape *)pango_map_get_engine (shape_map, script);
}

/* Utility functions */

/**
 * pango_win32_get_unknown_glyph:
 * @font: a #PangoFont
 * @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
 **/
PangoGlyph
pango_win32_get_unknown_glyph (PangoFont *font,
			       gunichar   wc)
{
  return PANGO_GET_UNKNOWN_GLYPH (wc);
}

/**
 * pango_win32_render_layout_line:
 * @hdc:       DC to use for uncolored drawing
 * @line:      a #PangoLayoutLine
 * @x:         the x position of start of string (in pixels)
 * @y:         the y position of baseline (in pixels)
 *
 * Render a #PangoLayoutLine onto a device context. For underlining to
 * work property the text alignment of the DC should have TA_BASELINE
 * and TA_LEFT.
 */
void
pango_win32_render_layout_line (HDC              hdc,
				PangoLayoutLine *line,
				int              x,
				int              y)
{
  GSList *tmp_list = line->runs;
  PangoRectangle overall_rect;
  PangoRectangle logical_rect;
  PangoRectangle ink_rect;

  int x_off = 0;

  pango_layout_line_get_extents (line,NULL, &overall_rect);

  while (tmp_list)
    {
      HBRUSH oldfg = NULL;
      HBRUSH brush = NULL;
      POINT points[2];
      PangoUnderline uline = PANGO_UNDERLINE_NONE;
      PangoLayoutRun *run = tmp_list->data;
      PangoAttrColor fg_color, bg_color;
      gboolean fg_set, bg_set;

      tmp_list = tmp_list->next;

      pango_win32_get_item_properties (run->item, &uline, &fg_color, &fg_set, &bg_color, &bg_set);

      if (uline == PANGO_UNDERLINE_NONE)
	pango_glyph_string_extents (run->glyphs, run->item->analysis.font,
				    NULL, &logical_rect);
      else
	pango_glyph_string_extents (run->glyphs, run->item->analysis.font,
				    &ink_rect, &logical_rect);

      if (bg_set)
	{
	  HBRUSH oldbrush;

	  brush = CreateSolidBrush (RGB ((bg_color.color.red + 128) >> 8,
					 (bg_color.color.green + 128) >> 8,
					 (bg_color.color.blue + 128) >> 8));
	  oldbrush = SelectObject (hdc, brush);
	  Rectangle (hdc, x + PANGO_PIXELS (x_off + logical_rect.x),
			  y + PANGO_PIXELS (overall_rect.y),
			  PANGO_PIXELS (logical_rect.width),
			  PANGO_PIXELS (overall_rect.height));
	  SelectObject (hdc, oldbrush);
	  DeleteObject (brush);
	}

      if (fg_set)
	{
	  brush = CreateSolidBrush (RGB ((fg_color.color.red + 128) >> 8,
					 (fg_color.color.green + 128) >> 8,
					 (fg_color.color.blue + 128) >> 8));
	  oldfg = SelectObject (hdc, brush);
	}

      pango_win32_render (hdc, run->item->analysis.font, run->glyphs,
			  x + PANGO_PIXELS (x_off), y);

      switch (uline)
	{
	case PANGO_UNDERLINE_NONE:
	  break;
	case PANGO_UNDERLINE_DOUBLE:
	  points[0].x = x + PANGO_PIXELS (x_off + ink_rect.x) - 1;
	  points[0].y = points[1].y = y + 4;
	  points[1].x = x + PANGO_PIXELS (x_off + ink_rect.x + ink_rect.width);
	  Polyline (hdc, points, 2);
	  points[0].y = points[1].y = y + 2;
	  Polyline (hdc, points, 2);
	  break;
	case PANGO_UNDERLINE_SINGLE:
	  points[0].x = x + PANGO_PIXELS (x_off + ink_rect.x) - 1;
	  points[0].y = points[1].y = y + 2;
	  points[1].x = x + PANGO_PIXELS (x_off + ink_rect.x + ink_rect.width);
	  Polyline (hdc, points, 2);
	  break;
	case PANGO_UNDERLINE_ERROR:
	  {
	    int point_x;
	    int counter = 0;
	    int end_x = x + PANGO_PIXELS (x_off + ink_rect.x + ink_rect.width);

	    for (point_x = x + PANGO_PIXELS (x_off + ink_rect.x) - 1;
		 point_x <= end_x;
		 point_x += 2)
	    {
	      points[0].x = point_x;
	      points[1].x = MAX (point_x + 1, end_x);

	      if (counter)
		points[0].y = points[1].y = y + 2;
	      else
		points[0].y = points[1].y = y + 3;

	      Polyline (hdc, points, 2);
	      counter = (counter + 1) % 2;
	    }
	  }
	  break;
	case PANGO_UNDERLINE_LOW:
	  points[0].x = x + PANGO_PIXELS (x_off + ink_rect.x) - 1;
	  points[0].y = points[1].y = y + PANGO_PIXELS (ink_rect.y + ink_rect.height) + 2;
	  points[1].x = x + PANGO_PIXELS (x_off + ink_rect.x + ink_rect.width);
	  Polyline (hdc, points, 2);
	  break;
	}

      if (fg_set)
	{
	  SelectObject (hdc, oldfg);
	  DeleteObject (brush);
	}

      x_off += logical_rect.width;
    }
}

/**
 * pango_win32_render_layout:
 * @hdc:       HDC to use for uncolored drawing
 * @layout:    a #PangoLayout
 * @x:         the X position of the left of the layout (in pixels)
 * @y:         the Y position of the top of the layout (in pixels)
 *
 * Render a #PangoLayoutLine onto an X drawable
 */
void
pango_win32_render_layout (HDC          hdc,
			   PangoLayout *layout,
			   int          x,
			   int          y)
{
  PangoLayoutIter *iter;

  g_return_if_fail (hdc != NULL);
  g_return_if_fail (PANGO_IS_LAYOUT (layout));

  iter = pango_layout_get_iter (layout);

  do
    {
      PangoRectangle   logical_rect;
      PangoLayoutLine *line;
      int              baseline;

      line = pango_layout_iter_get_line_readonly (iter);

      pango_layout_iter_get_line_extents (iter, NULL, &logical_rect);
      baseline = pango_layout_iter_get_baseline (iter);

      pango_win32_render_layout_line (hdc,
				      line,
				      x + PANGO_PIXELS (logical_rect.x),
				      y + PANGO_PIXELS (baseline));
    }
  while (pango_layout_iter_next_line (iter));

  pango_layout_iter_free (iter);
}

/* This utility function is duplicated here and in pango-layout.c; should it be
 * public? Trouble is - what is the appropriate set of properties?
 */
static void
pango_win32_get_item_properties (PangoItem      *item,
				 PangoUnderline *uline,
				 PangoAttrColor *fg_color,
				 gboolean       *fg_set,
				 PangoAttrColor *bg_color,
				 gboolean       *bg_set)
{
  GSList *tmp_list = item->analysis.extra_attrs;

  if (fg_set)
    *fg_set = FALSE;

  if (bg_set)
    *bg_set = FALSE;

  while (tmp_list)
    {
      PangoAttribute *attr = tmp_list->data;

      switch (attr->klass->type)
	{
	case PANGO_ATTR_UNDERLINE:
	  if (uline)
	    *uline = ((PangoAttrInt *)attr)->value;
	  break;

	case PANGO_ATTR_FOREGROUND:
	  if (fg_color)
	    *fg_color = *((PangoAttrColor *)attr);
	  if (fg_set)
	    *fg_set = TRUE;

	  break;

	case PANGO_ATTR_BACKGROUND:
	  if (bg_color)
	    *bg_color = *((PangoAttrColor *)attr);
	  if (bg_set)
	    *bg_set = TRUE;

	  break;

	default:
	  break;
	}
      tmp_list = tmp_list->next;
    }
}

static guint
get_cmap_offset (HDC     hdc,
		 guint16 encoding_id)
{
  guint16 n_tables;
  struct cmap_encoding_subtable *table;
  gint32 res;
  int i;
  guint32 offset;

  /* Get The number of encoding tables, at offset 2 */
  res = GetFontData (hdc, CMAP, 2, &n_tables, 2);
  if (res != 2)
    return 0;

  n_tables = GUINT16_FROM_BE (n_tables);

  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)