st/hb.c

140 lines
3.4 KiB
C

#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <time.h>
#include <X11/Xft/Xft.h>
#include <X11/cursorfont.h>
#include <hb.h>
#include <hb-ft.h>
#include "st.h"
#include "hb.h"
#define FEATURE(c1,c2,c3,c4) { .tag = HB_TAG(c1,c2,c3,c4), .value = 1, .start = HB_FEATURE_GLOBAL_START, .end = HB_FEATURE_GLOBAL_END }
#define BUFFER_STEP 256
hb_font_t *hbfindfont(XftFont *match);
typedef struct {
XftFont *match;
hb_font_t *font;
} HbFontMatch;
typedef struct {
size_t capacity;
HbFontMatch *fonts;
} HbFontCache;
static HbFontCache hbfontcache = { 0, NULL };
typedef struct {
size_t capacity;
Rune *runes;
} RuneBuffer;
static RuneBuffer hbrunebuffer = { 0, NULL };
static hb_buffer_t *hbbuffer;
/*
* Poplulate the array with a list of font features, wrapped in FEATURE macro,
* e. g.
* FEATURE('c', 'a', 'l', 't'), FEATURE('d', 'l', 'i', 'g')
*/
hb_feature_t features[] = { };
void
hbcreatebuffer(void)
{
hbbuffer = hb_buffer_create();
}
void
hbdestroybuffer(void)
{
hb_buffer_destroy(hbbuffer);
}
void
hbunloadfonts(void)
{
for (int i = 0; i < hbfontcache.capacity; i++) {
hb_font_destroy(hbfontcache.fonts[i].font);
XftUnlockFace(hbfontcache.fonts[i].match);
}
if (hbfontcache.fonts != NULL) {
free(hbfontcache.fonts);
hbfontcache.fonts = NULL;
}
hbfontcache.capacity = 0;
}
hb_font_t *
hbfindfont(XftFont *match)
{
for (int i = 0; i < hbfontcache.capacity; i++) {
if (hbfontcache.fonts[i].match == match)
return hbfontcache.fonts[i].font;
}
/* Font not found in cache, caching it now. */
hbfontcache.fonts = realloc(hbfontcache.fonts, sizeof(HbFontMatch) * (hbfontcache.capacity + 1));
FT_Face face = XftLockFace(match);
hb_font_t *font = hb_ft_font_create(face, NULL);
if (font == NULL)
die("Failed to load Harfbuzz font.");
hbfontcache.fonts[hbfontcache.capacity].match = match;
hbfontcache.fonts[hbfontcache.capacity].font = font;
hbfontcache.capacity += 1;
return font;
}
void
hbtransform(HbTransformData *data, XftFont *xfont, const Glyph *glyphs, int start, int length)
{
uint32_t mode;
unsigned int glyph_count;
int rune_idx, glyph_idx, end = start + length;
hb_buffer_t *buffer = hbbuffer;
hb_font_t *font = hbfindfont(xfont);
if (font == NULL) {
data->count = 0;
return;
}
hb_buffer_reset(buffer);
hb_buffer_set_direction(buffer, HB_DIRECTION_LTR);
hb_buffer_set_cluster_level(buffer, HB_BUFFER_CLUSTER_LEVEL_MONOTONE_CHARACTERS);
/* Resize the buffer if required length is larger. */
if (hbrunebuffer.capacity < length) {
hbrunebuffer.capacity = (length / BUFFER_STEP + 1) * BUFFER_STEP;
hbrunebuffer.runes = realloc(hbrunebuffer.runes, hbrunebuffer.capacity * sizeof(Rune));
}
/* Fill buffer with codepoints. */
for (rune_idx = 0, glyph_idx = start; glyph_idx < end; glyph_idx++, rune_idx++) {
hbrunebuffer.runes[rune_idx] = glyphs[glyph_idx].u;
mode = glyphs[glyph_idx].mode;
if (mode & ATTR_WDUMMY)
hbrunebuffer.runes[rune_idx] = 0x0020;
}
hb_buffer_add_codepoints(buffer, hbrunebuffer.runes, length, 0, length);
/* Shape the segment. */
hb_shape(font, buffer, features, sizeof(features)/sizeof(hb_feature_t));
/* Get new glyph info. */
hb_glyph_info_t *info = hb_buffer_get_glyph_infos(buffer, &glyph_count);
hb_glyph_position_t *pos = hb_buffer_get_glyph_positions(buffer, &glyph_count);
/* Fill the output. */
data->buffer = buffer;
data->glyphs = info;
data->positions = pos;
data->count = glyph_count;
}