static PangoFontMetrics *
pango_cairo_core_text_font_create_base_metrics_for_context (PangoCairoFont *font,
PangoContext *context)
{
PangoCoreTextFont *cfont = (PangoCoreTextFont *) font;
PangoFontMetrics *metrics;
PangoFontDescription *font_desc;
PangoLayout *layout;
PangoRectangle extents;
PangoLanguage *language = pango_context_get_language (context);
const char *sample_str = pango_language_get_sample_string (language);
CTFontRef ctfont;
metrics = pango_font_metrics_new ();
ctfont = pango_core_text_font_get_ctfont (cfont);
metrics->ascent = CTFontGetAscent (ctfont) * PANGO_SCALE;
metrics->descent = CTFontGetDescent (ctfont) * PANGO_SCALE;
metrics->underline_position = CTFontGetUnderlinePosition (ctfont) * PANGO_SCALE;
metrics->underline_thickness = CTFontGetUnderlineThickness (ctfont) * PANGO_SCALE;
metrics->strikethrough_position = metrics->ascent / 3;
metrics->strikethrough_thickness = CTFontGetUnderlineThickness (ctfont) * PANGO_SCALE;
layout = pango_layout_new (context);
font_desc = pango_font_describe_with_absolute_size ((PangoFont *) font);
pango_layout_set_font_description (layout, font_desc);
pango_layout_set_text (layout, sample_str, -1);
pango_layout_get_extents (layout, NULL, &extents);
metrics->approximate_char_width = extents.width / pango_utf8_strwidth (sample_str);
pango_layout_set_text (layout, "0123456789", -1);
metrics->approximate_digit_width = max_glyph_width (layout);
pango_font_description_free (font_desc);
g_object_unref (layout);
return metrics;
}
PangoFontMetrics *
_pango_cairo_font_get_metrics (PangoFont *font,
PangoLanguage *language)
{
PangoCairoFont *cfont = (PangoCairoFont *) font;
PangoCairoFontPrivate *cf_priv = PANGO_CAIRO_FONT_PRIVATE (font);
PangoCairoFontMetricsInfo *info = NULL; /* Quiet gcc */
GSList *tmp_list;
const char *sample_str = pango_language_get_sample_string (language);
tmp_list = cf_priv->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)
{
PangoFontMap *fontmap;
PangoContext *context;
cairo_font_options_t *font_options;
PangoLayout *layout;
PangoRectangle extents;
PangoFontDescription *desc;
cairo_scaled_font_t *scaled_font;
cairo_matrix_t cairo_matrix;
PangoMatrix pango_matrix;
PangoMatrix identity = PANGO_MATRIX_INIT;
int height, shift;
/* XXX this is racy. need a ref'ing getter... */
fontmap = pango_font_get_font_map (font);
if (!fontmap)
return pango_font_metrics_new ();
fontmap = g_object_ref (fontmap);
info = g_slice_new0 (PangoCairoFontMetricsInfo);
cf_priv->metrics_by_lang = g_slist_prepend (cf_priv->metrics_by_lang, info);
info->sample_str = sample_str;
scaled_font = _pango_cairo_font_private_get_scaled_font (cf_priv);
context = pango_font_map_create_context (fontmap);
pango_context_set_language (context, language);
font_options = cairo_font_options_create ();
cairo_scaled_font_get_font_options (scaled_font, font_options);
pango_cairo_context_set_font_options (context, font_options);
cairo_font_options_destroy (font_options);
info->metrics = (* PANGO_CAIRO_FONT_GET_IFACE (font)->create_base_metrics_for_context) (cfont, context);
/* We now need to adjust the base metrics for ctm */
cairo_scaled_font_get_ctm (scaled_font, &cairo_matrix);
pango_matrix.xx = cairo_matrix.xx;
pango_matrix.yx = cairo_matrix.yx;
pango_matrix.xy = cairo_matrix.xy;
pango_matrix.yy = cairo_matrix.yy;
pango_matrix.x0 = 0;
pango_matrix.y0 = 0;
if (G_UNLIKELY (0 != memcmp (&identity, &pango_matrix, 4 * sizeof (double))))
{
double xscale = pango_matrix_get_font_scale_factor (&pango_matrix);
if (xscale) xscale = 1 / xscale;
info->metrics->ascent *= xscale;
info->metrics->descent *= xscale;
info->metrics->underline_position *= xscale;
info->metrics->underline_thickness *= xscale;
info->metrics->strikethrough_position *= xscale;
info->metrics->strikethrough_thickness *= xscale;
}
/* Set the matrix on the context so we don't have to adjust the derived
* metrics. */
pango_context_set_matrix (context, &pango_matrix);
/* Update approximate_*_width now */
layout = pango_layout_new (context);
desc = pango_font_describe_with_absolute_size (font);
pango_layout_set_font_description (layout, desc);
pango_font_description_free (desc);
pango_layout_set_text (layout, sample_str, -1);
pango_layout_get_extents (layout, NULL, &extents);
info->metrics->approximate_char_width = extents.width / pango_utf8_strwidth (sample_str);
pango_layout_set_text (layout, "0123456789", -1);
info->metrics->approximate_digit_width = max_glyph_width (layout);
g_object_unref (layout);
/* We may actually reuse ascent/descent we got from cairo here. that's
* in cf_priv->font_extents.
*/
height = info->metrics->ascent + info->metrics->descent;
switch (cf_priv->gravity)
{
default:
case PANGO_GRAVITY_AUTO:
case PANGO_GRAVITY_SOUTH:
break;
case PANGO_GRAVITY_NORTH:
info->metrics->ascent = info->metrics->descent;
break;
case PANGO_GRAVITY_EAST:
case PANGO_GRAVITY_WEST:
{
int ascent = height / 2;
if (cf_priv->is_hinted)
ascent = PANGO_UNITS_ROUND (ascent);
info->metrics->ascent = ascent;
}
}
shift = (height - info->metrics->ascent) - info->metrics->descent;
info->metrics->descent += shift;
info->metrics->underline_position -= shift;
info->metrics->strikethrough_position -= shift;
info->metrics->ascent = height - info->metrics->descent;
g_object_unref (context);
g_object_unref (fontmap);
}
return pango_font_metrics_ref (info->metrics);
}