netsurf/framebuffer/fb_font.c

135 lines
4.0 KiB
C

/*
* Copyright 2005 James Bursa <bursa@users.sourceforge.net>
* 2008 Vincent Sanders <vince@simtec.co.uk>
*
* This file is part of NetSurf, http://www.netsurf-browser.org/
*
* NetSurf 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; version 2 of the License.
*
* NetSurf 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 this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <inttypes.h>
#include <assert.h>
#include "css/css.h"
#include "render/font.h"
#include "desktop/options.h"
#include "utils/utf8.h"
#include "framebuffer/fb_gui.h"
#include "framebuffer/fb_font.h"
const struct fb_font_desc*
fb_get_font(const struct css_style *style)
{
return &font_vga_8x16;
}
utf8_convert_ret utf8_to_font_encoding(const struct fb_font_desc* font,
const char *string,
size_t len,
char **result)
{
return utf8_to_enc(string, font->encoding, len, result);
}
utf8_convert_ret utf8_to_local_encoding(const char *string,
size_t len,
char **result)
{
return utf8_to_enc(string, "CP437", len, result);
}
static bool nsfont_width(const struct css_style *style,
const char *string, size_t length,
int *width)
{
const struct fb_font_desc* fb_font = fb_get_font(style);
*width = fb_font->width * length;
return true;
}
/**
* Find the position in a string where an x coordinate falls.
*
* \param style css_style for this text, with style->font_size.size ==
* CSS_FONT_SIZE_LENGTH
* \param string UTF-8 string to measure
* \param length length of string
* \param x x coordinate to search for
* \param char_offset updated to offset in string of actual_x, [0..length]
* \param actual_x updated to x coordinate of character closest to x
* \return true on success, false on error and error reported
*/
static bool nsfont_position_in_string(const struct css_style *style,
const char *string, size_t length,
int x, size_t *char_offset, int *actual_x)
{
const struct fb_font_desc* fb_font = fb_get_font(style);
*char_offset = x / fb_font->width;
*actual_x = *char_offset * fb_font->width;
return true;
}
/**
* Find where to split a string to make it fit a width.
*
* \param style css_style for this text, with style->font_size.size ==
* CSS_FONT_SIZE_LENGTH
* \param string UTF-8 string to measure
* \param length length of string
* \param x width available
* \param char_offset updated to offset in string of actual_x, [0..length]
* \param actual_x updated to x coordinate of character closest to x
* \return true on success, false on error and error reported
*
* On exit, [char_offset == 0 ||
* string[char_offset] == ' ' ||
* char_offset == length]
*/
static bool nsfont_split(const struct css_style *style,
const char *string, size_t length,
int x, size_t *char_offset, int *actual_x)
{
const struct fb_font_desc* fb_font = fb_get_font(style);
*char_offset = x / fb_font->width;
if (*char_offset > length) {
*char_offset = length;
} else {
while (*char_offset > 0) {
if (string[*char_offset] == ' ')
break;
(*char_offset)--;
}
}
*actual_x = *char_offset * fb_font->width;
return true;
}
const struct font_functions nsfont = {
nsfont_width,
nsfont_position_in_string,
nsfont_split
};
/*
* Local Variables:
* c-basic-offset:8
* End:
*/