quakeforge/libs/video/renderer/r_text.c
Bill Currie 935e883d8d [renderer] Switch to using HarfBuzz for glyph positioning
This means that QF should support more exotic fonts without any issue
(once the rest of the text handling system is up to snuff) as HarfBuzz
does all the hard work of handling OpenType, Graphite, etc text shaping,
including kerning (when enabled).

Also, font loading now loads all the glyphs into the atlas (preload is
gone).
2022-09-04 20:56:38 +09:00

113 lines
2.9 KiB
C

/*
r_font.c
Renderer font management management
Copyright (C) 2022 Bill Currie <bill@taniwha.org>
Author: Bill Currie <bill@taniwha.org>
Date: 2022/8/26
This program 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 2
of the License, or (at your option) any later version.
This program 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, write to:
Free Software Foundation, Inc.
59 Temple Place - Suite 330
Boston, MA 02111-1307, USA
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <math.h>
#include "QF/quakefs.h"
#include "QF/sys.h"
#include "r_font.h"
#include "r_text.h"
#include "compat.h"
rshaper_t *
RText_NewShaper (rfont_t *font)
{
rshaper_t *shaper = malloc (sizeof (rshaper_t));
shaper->rfont = font;
shaper->font = hb_ft_font_create (font->face, 0);
shaper->buffer = hb_buffer_create ();
shaper->features = (r_hb_featureset_t) DARRAY_STATIC_INIT (4);
hb_buffer_allocation_successful (shaper->buffer);
return shaper;
}
void
RText_DeleteShaper (rshaper_t *shaper)
{
hb_buffer_destroy (shaper->buffer);
hb_font_destroy (shaper->font);
DARRAY_CLEAR (&shaper->features);
free (shaper);
}
void
RText_AddFeature (rshaper_t *shaper, hb_feature_t feature)
{
DARRAY_APPEND (&shaper->features, feature);
}
void
RText_ShapeText (rshaper_t *shaper, rtext_t *text)
{
hb_buffer_reset (shaper->buffer);
hb_buffer_set_direction (shaper->buffer, text->direction);
hb_buffer_set_script (shaper->buffer, text->script);
const char *lang = text->language;
hb_buffer_set_language (shaper->buffer,
hb_language_from_string (lang, strlen (lang)));
size_t length = strlen (text->text);
hb_buffer_add_utf8 (shaper->buffer, text->text, length, 0, length);
hb_shape (shaper->font, shaper->buffer,
shaper->features.a, shaper->features.size);
}
void
RText_RenderText (rshaper_t *shaper, rtext_t *text, int x, int y,
rtext_render_t *render, void *data)
{
RText_ShapeText (shaper, text);
unsigned count;
__auto_type glyphInfo = hb_buffer_get_glyph_infos (shaper->buffer, &count);
__auto_type glyphPos = hb_buffer_get_glyph_positions (shaper->buffer,
&count);
rfont_t *font = shaper->rfont;
for (unsigned i = 0; i < count; i++) {
rglyph_t *glyph = &font->glyphs[glyphInfo[i].codepoint];
int xp = x + glyphPos[i].x_offset / 64;
int yp = y + glyphPos[i].y_offset / 64;
int xa = glyphPos[i].x_advance / 64;
int ya = glyphPos[i].y_advance / 64;
xp += glyph->bearing[0];
yp -= glyph->bearing[1];
render (glyph, xp, yp, data);
x += xa;
y += ya;
}
}