grub/gfxmenu/font.c
Vladimir 'phcoder' Serbinenko 97b3fbb872 Handle initial position in bidi
2010-03-16 10:55:06 +01:00

108 lines
3.2 KiB
C

/* font.c - Font API and font file loader. */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2003,2005,2006,2007,2008,2009,2010 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/bufio.h>
#include <grub/dl.h>
#include <grub/file.h>
#include <grub/font.h>
#include <grub/misc.h>
#include <grub/mm.h>
#include <grub/types.h>
#include <grub/video.h>
#include <grub/bitmap.h>
#include <grub/charset.h>
#include <grub/unicode.h>
#include <grub/fontformat.h>
/* Draw a UTF-8 string of text on the current video render target.
The x coordinate specifies the starting x position for the first character,
while the y coordinate specifies the baseline position.
If the string contains a character that FONT does not contain, then
a glyph from another loaded font may be used instead. */
grub_err_t
grub_font_draw_string (const char *str, grub_font_t font,
grub_video_color_t color,
int left_x, int baseline_y)
{
int x;
struct grub_font_glyph *glyph;
grub_uint32_t *logical;
grub_ssize_t logical_len, visual_len;
struct grub_unicode_glyph *visual, *ptr;
logical_len = grub_utf8_to_ucs4_alloc (str, &logical, 0);
if (logical_len < 0)
return grub_errno;
visual_len = grub_bidi_logical_to_visual (logical, logical_len, &visual,
0, 0, 0);
grub_free (logical);
if (visual_len < 0)
return grub_errno;
for (ptr = visual, x = left_x; ptr < visual + visual_len; ptr++)
{
grub_err_t err;
glyph = grub_font_construct_glyph (font, ptr);
if (!glyph)
return grub_errno;
err = grub_font_draw_glyph (glyph, color, x, baseline_y);
grub_free (glyph);
if (err)
return err;
x += glyph->device_width;
}
grub_free (visual);
return GRUB_ERR_NONE;
}
/* Get the width in pixels of the specified UTF-8 string, when rendered in
in the specified font (but falling back on other fonts for glyphs that
are missing). */
int
grub_font_get_string_width (grub_font_t font, const char *str)
{
int width = 0;
grub_uint32_t *ptr;
grub_ssize_t logical_len;
grub_uint32_t *logical;
logical_len = grub_utf8_to_ucs4_alloc (str, &logical, 0);
if (logical_len < 0)
{
grub_errno = GRUB_ERR_NONE;
return 0;
}
for (ptr = logical; ptr < logical + logical_len;)
{
struct grub_unicode_glyph glyph;
ptr += grub_unicode_aglomerate_comb (ptr,
logical_len - (ptr - logical),
&glyph);
width += grub_font_get_constructed_device_width (font, &glyph);
grub_free (glyph.combining);
}
return width;
}