+ ++it->glyph_row->used[area];
+ }
+ else
+ IT_EXPAND_MATRIX_WIDTH (it, area);
+}
+
+
+/* Produce a glyph for a glyphless character for iterator IT.
+ IT->glyphless_method specifies which method to use for displaying
+ the character. See the description of enum
+ glyphless_display_method in dispextern.h for the detail.
+
+ FOR_NO_FONT is nonzero if and only if this is for a character for
+ which no font was found. ACRONYM, if non-nil, is an acronym string
+ for the character. */
+
+static void
+produce_glyphless_glyph (struct it *it, int for_no_font, Lisp_Object acronym)
+{
+ int face_id;
+ struct face *face;
+ struct font *font;
+ int base_width, base_height, width, height;
+ short upper_xoff, upper_yoff, lower_xoff, lower_yoff;
+ int len;
+
+ /* Get the metrics of the base font. We always refer to the current
+ ASCII face. */
+ face = FACE_FROM_ID (it->f, it->face_id)->ascii_face;
+ font = face->font ? face->font : FRAME_FONT (it->f);
+ it->ascent = FONT_BASE (font) + font->baseline_offset;
+ it->descent = FONT_DESCENT (font) - font->baseline_offset;
+ base_height = it->ascent + it->descent;
+ base_width = font->average_width;
+
+ /* Get a face ID for the glyph by utilizing a cache (the same way as
+ doen for `escape-glyph' in get_next_display_element). */
+ if (it->f == last_glyphless_glyph_frame
+ && it->face_id == last_glyphless_glyph_face_id)
+ {
+ face_id = last_glyphless_glyph_merged_face_id;
+ }
+ else
+ {
+ /* Merge the `glyphless-char' face into the current face. */
+ face_id = merge_faces (it->f, Qglyphless_char, 0, it->face_id);
+ last_glyphless_glyph_frame = it->f;
+ last_glyphless_glyph_face_id = it->face_id;
+ last_glyphless_glyph_merged_face_id = face_id;
+ }
+
+ if (it->glyphless_method == GLYPHLESS_DISPLAY_THIN_SPACE)
+ {
+ it->pixel_width = THIN_SPACE_WIDTH;
+ len = 0;
+ upper_xoff = upper_yoff = lower_xoff = lower_yoff = 0;
+ }
+ else if (it->glyphless_method == GLYPHLESS_DISPLAY_EMPTY_BOX)
+ {
+ width = CHAR_WIDTH (it->c);
+ if (width == 0)
+ width = 1;
+ else if (width > 4)
+ width = 4;
+ it->pixel_width = base_width * width;
+ len = 0;
+ upper_xoff = upper_yoff = lower_xoff = lower_yoff = 0;
+ }
+ else
+ {
+ char buf[7], *str;
+ unsigned int code[6];
+ int upper_len;
+ int ascent, descent;
+ struct font_metrics metrics_upper, metrics_lower;
+
+ face = FACE_FROM_ID (it->f, face_id);
+ font = face->font ? face->font : FRAME_FONT (it->f);
+ PREPARE_FACE_FOR_DISPLAY (it->f, face);
+
+ if (it->glyphless_method == GLYPHLESS_DISPLAY_ACRONYM)
+ {
+ if (! STRINGP (acronym) && CHAR_TABLE_P (Vglyphless_char_display))
+ acronym = CHAR_TABLE_REF (Vglyphless_char_display, it->c);
+ str = STRINGP (acronym) ? SSDATA (acronym) : "";
+ }
+ else
+ {
+ xassert (it->glyphless_method == GLYPHLESS_DISPLAY_HEX_CODE);
+ sprintf (buf, "%0*X", it->c < 0x10000 ? 4 : 6, it->c);
+ str = buf;
+ }
+ for (len = 0; str[len] && ASCII_BYTE_P (str[len]); len++)
+ code[len] = font->driver->encode_char (font, str[len]);
+ upper_len = (len + 1) / 2;
+ font->driver->text_extents (font, code, upper_len,
+ &metrics_upper);
+ font->driver->text_extents (font, code + upper_len, len - upper_len,
+ &metrics_lower);
+
+
+
+ /* +4 is for vertical bars of a box plus 1-pixel spaces at both side. */
+ width = max (metrics_upper.width, metrics_lower.width) + 4;
+ upper_xoff = upper_yoff = 2; /* the typical case */
+ if (base_width >= width)
+ {
+ /* Align the upper to the left, the lower to the right. */
+ it->pixel_width = base_width;
+ lower_xoff = base_width - 2 - metrics_lower.width;
+ }
+ else
+ {
+ /* Center the shorter one. */
+ it->pixel_width = width;
+ if (metrics_upper.width >= metrics_lower.width)
+ lower_xoff = (width - metrics_lower.width) / 2;
+ else
+ upper_xoff = (width - metrics_upper.width) / 2;
+ }
+
+ /* +5 is for horizontal bars of a box plus 1-pixel spaces at
+ top, bottom, and between upper and lower strings. */
+ height = (metrics_upper.ascent + metrics_upper.descent
+ + metrics_lower.ascent + metrics_lower.descent) + 5;
+ /* Center vertically.
+ H:base_height, D:base_descent
+ h:height, ld:lower_descent, la:lower_ascent, ud:upper_descent
+
+ ascent = - (D - H/2 - h/2 + 1); "+ 1" for rounding up
+ descent = D - H/2 + h/2;
+ lower_yoff = descent - 2 - ld;
+ upper_yoff = lower_yoff - la - 1 - ud; */
+ ascent = - (it->descent - (base_height + height + 1) / 2);
+ descent = it->descent - (base_height - height) / 2;
+ lower_yoff = descent - 2 - metrics_lower.descent;
+ upper_yoff = (lower_yoff - metrics_lower.ascent - 1
+ - metrics_upper.descent);
+ /* Don't make the height shorter than the base height. */
+ if (height > base_height)
+ {
+ it->ascent = ascent;
+ it->descent = descent;
+ }
+ }
+
+ it->phys_ascent = it->ascent;
+ it->phys_descent = it->descent;
+ if (it->glyph_row)
+ append_glyphless_glyph (it, face_id, for_no_font, len,
+ upper_xoff, upper_yoff,
+ lower_xoff, lower_yoff);
+ it->nglyphs = 1;
+ take_vertical_position_into_account (it);
+}
+
+
+/* RIF:
+ Produce glyphs/get display metrics for the display element IT is
+ loaded with. See the description of struct it in dispextern.h
+ for an overview of struct it. */
+
+void
+x_produce_glyphs (struct it *it)
+{
+ int extra_line_spacing = it->extra_line_spacing;
+
+ it->glyph_not_available_p = 0;
+
+ if (it->what == IT_CHARACTER)
+ {
+ XChar2b char2b;
+ struct face *face = FACE_FROM_ID (it->f, it->face_id);
+ struct font *font = face->font;
+ struct font_metrics *pcm = NULL;
+ int boff; /* baseline offset */
+
+ if (font == NULL)
+ {
+ /* When no suitable font is found, display this character by
+ the method specified in the first extra slot of
+ Vglyphless_char_display. */
+ Lisp_Object acronym = lookup_glyphless_char_display (-1, it);
+
+ xassert (it->what == IT_GLYPHLESS);
+ produce_glyphless_glyph (it, 1, STRINGP (acronym) ? acronym : Qnil);
+ goto done;
+ }
+
+ boff = font->baseline_offset;
+ if (font->vertical_centering)
+ boff = VCENTER_BASELINE_OFFSET (font, it->f) - boff;
+
+ if (it->char_to_display != '\n' && it->char_to_display != '\t')