ref: b0377e84cf31c48afed765c433abe7eebb4135a5
dir: /sys/src/libttf/glyf.c/
#include <u.h>
#include <libc.h>
#include <bio.h>
#include <draw.h>
#include <ctype.h>
#include <ttf.h>
#include "impl.h"
void
ttfputglyph(TTGlyph *g)
{
if(g == nil) return;
free(g->pt);
free(g->ptorg);
free(g->confst);
free(g->bit);
free(g->hint);
free(g);
}
static void
glyphscale(TTGlyph *g)
{
TTFont *f;
int i;
TTPoint *p;
f = g->font;
for(i = 0; i < g->npt; i++){
p = &g->pt[i];
p->x = ttfrounddiv(p->x * f->ppem * 64, f->u->emsize);
p->y = ttfrounddiv(p->y * f->ppem * 64, f->u->emsize);
}
memmove(g->ptorg, g->pt, sizeof(TTPoint) * g->npt);
g->pt[g->npt - 1].x = g->pt[g->npt - 1].x + 32 & -64;
}
static TTGlyph *
emptyglyph(TTFont *fs, int glyph, int render)
{
TTGlyph *g;
g = mallocz(sizeof(TTGlyph), 1);
if(g == nil)
return nil;
g->font = fs;
g->info = &fs->u->ginfo[glyph];
g->confst = malloc(sizeof(int));
g->npt = 2;
g->pt = mallocz(sizeof(TTPoint) * 2, 1);
g->ptorg = mallocz(sizeof(TTPoint) * 2, 1);
if(g->confst == nil || g->pt == nil || g->ptorg == nil){
ttfputglyph(g);
return nil;
}
g->pt[1].x = g->info->advanceWidth;
g->npt = 2;
if(render)
glyphscale(g);
g->xmin = 0;
g->ymin = 0;
g->xmax = g->info->advanceWidth;
g->ymax = 1;
if(render){
g->xminpx = 0;
g->xmaxpx = (g->xmax * fs->ppem + fs->u->emsize - 1) / fs->u->emsize;
g->yminpx = 0;
g->ymaxpx = 1;
}
return g;
}
static TTGlyph *
simpglyph(TTFont *fs, int glyph, int nc, int render)
{
u16int np;
short x;
u16int len;
u16int temp16;
u8int temp8;
u8int *flags, *fp, *fq;
TTPoint *p;
int i, j, r;
short lastx, lasty;
TTFontU *f;
TTGlyph *g;
flags = nil;
f = fs->u;
g = mallocz(sizeof(TTGlyph), 1);
if(g == nil)
return nil;
g->font = fs;
g->info = &f->ginfo[glyph];
g->confst = malloc(sizeof(u16int) * (nc + 1));
if(g->confst == nil)
goto err;
x = -1;
for(i = g->ncon; i < nc; i++){
g->confst[i] = x + 1;
ttfunpack(f, "w", &x);
}
g->confst[i] = x + 1;
g->ncon = nc;
np = x + 1;
ttfunpack(f, "w", &len);
g->nhint = len;
g->hint = mallocz(len, 1);
if(g->hint == nil)
goto err;
Bread(f->bin, g->hint, len);
flags = mallocz(np, 1);
if(flags == nil)
goto err;
for(i = 0; i < np; i++){
j = Bgetc(f->bin);
flags[i] = j;
if((j & 8) != 0){
r = Bgetc(f->bin);
while(r-- > 0)
flags[++i] = j;
}
}
fp = flags;
fq = flags;
lastx = lasty = 0;
g->pt = malloc(sizeof(TTPoint) * (np + 2));
if(g->pt == nil)
goto err;
g->ptorg = malloc(sizeof(TTPoint) * (np + 2));
if(g->ptorg == nil)
goto err;
for(i = 0; i < np; i++){
p = &g->pt[g->npt + i];
p->flags = *fp & 1;
switch(*fp++ & 0x12){
case 0x00: ttfunpack(f, "w", &temp16); p->x = lastx += temp16; break;
case 0x02: ttfunpack(f, "b", &temp8); p->x = lastx -= temp8; break;
case 0x10: p->x = lastx; break;
case 0x12: ttfunpack(f, "b", &temp8); p->x = lastx += temp8; break;
}
}
for(i = 0; i < np; i++){
p = &g->pt[g->npt + i];
switch(*fq++ & 0x24){
case 0x00: ttfunpack(f, "w", &temp16); p->y = lasty += temp16; break;
case 0x04: ttfunpack(f, "b", &temp8); p->y = lasty -= temp8; break;
case 0x20: p->y = lasty; break;
case 0x24: ttfunpack(f, "b", &temp8); p->y = lasty += temp8; break;
}
}
g->pt[np] = (TTPoint){0,0,0};
g->pt[np+1] = (TTPoint){f->ginfo[glyph].advanceWidth,0,0};
g->npt = np + 2;
free(flags);
if(render){
glyphscale(g);
ttfhint(g);
}
return g;
err:
free(flags);
ttfputglyph(g);
return nil;
}
static TTGlyph *getglyph(TTFont *, int, int);
enum {
ARG_1_AND_2_ARE_WORDS = 1<<0,
ARGS_ARE_XY_VALUES = 1<<1,
ROUND_XY_TO_GRID = 1<<2,
WE_HAVE_A_SCALE = 1<<3,
MORE_COMPONENTS = 1<<5,
WE_HAVE_AN_X_AND_Y_SCALE = 1<<6,
WE_HAVE_A_TWO_BY_TWO = 1<<7,
WE_HAVE_INSTRUCTIONS = 1<<8,
USE_MY_METRICS = 1<<9,
OVERLAP_COMPOUND = 1<<10,
};
static int
mergeglyph(TTGlyph *g, TTGlyph *h, int flags, int x, int y, int a, int b, int c, int d, int render)
{
int i, m;
TTPoint *p;
TTFont *f;
int dx, dy;
f = g->font;
g->confst = realloc(g->confst, sizeof(int) * (g->ncon + h->ncon + 1));
for(i = 1; i <= h->ncon; i++)
g->confst[g->ncon + i] = g->confst[g->ncon] + h->confst[i];
g->ncon += h->ncon;
g->pt = realloc(g->pt, sizeof(TTPoint) * (g->npt + h->npt - 2));
if((flags & USE_MY_METRICS) == 0){
memmove(g->pt + g->npt + h->npt - 4, g->pt + g->npt - 2, 2 * sizeof(TTPoint));
m = h->npt - 2;
}else
m = h->npt;
for(i = 0; i < m; i++){
p = &g->pt[g->npt - 2 + i];
*p = h->pt[i];
dx = ttfrounddiv(p->x * a + p->y * b, 16384);
dy = ttfrounddiv(p->x * c + p->y * d, 16384);
p->x = dx;
p->y = dy;
if((flags & ARGS_ARE_XY_VALUES) != 0){
if(render){
dx = ttfrounddiv(x * f->ppem * 64, f->u->emsize);
dy = ttfrounddiv(y * f->ppem * 64, f->u->emsize);
if((flags & ROUND_XY_TO_GRID) != 0){
dx = dx + 32 & -64;
dy = dy + 32 & -64;
}
}
p->x += dx;
p->y += dy;
}else
abort();
}
g->npt += h->npt - 2;
return 0;
}
static TTGlyph *
compglyph(TTFont *fs, int glyph, int render)
{
u16int flags, idx;
int x, y;
int a, b, c, d;
TTFontU *f;
uvlong off;
TTGlyph *g, *h;
u16int len;
f = fs->u;
g = mallocz(sizeof(TTGlyph), 1);
if(g == nil)
return nil;
g->font = fs;
g->info = &f->ginfo[glyph];
g->pt = mallocz(sizeof(TTPoint) * 2, 1);
if(g->pt == nil){
err:
ttfputglyph(g);
return nil;
}
g->pt[1].x = ttfrounddiv(f->ginfo[glyph].advanceWidth * fs->ppem * 64, f->emsize);
g->npt = 2;
g->confst = mallocz(sizeof(int), 1);
if(g->confst == nil)
goto err;
do{
ttfunpack(f, "ww", &flags, &idx);
switch(flags & (ARG_1_AND_2_ARE_WORDS | ARGS_ARE_XY_VALUES)){
case 0: ttfunpack(f, "BB", &x, &y); break;
case ARGS_ARE_XY_VALUES: ttfunpack(f, "BB", &x, &y); x = (char)x; y = (char)y; break;
case ARG_1_AND_2_ARE_WORDS: ttfunpack(f, "WW", &x, &y); break;
case ARG_1_AND_2_ARE_WORDS | ARGS_ARE_XY_VALUES: ttfunpack(f, "WW", &x, &y); x = (short)x; y = (short)y; break;
}
if((flags & WE_HAVE_A_SCALE) != 0){
ttfunpack(f, "S", &a);
d = a;
b = c = 0;
}else if((flags & WE_HAVE_AN_X_AND_Y_SCALE) != 0){
ttfunpack(f, "SS", &a, &d);
b = c = 0;
}else if((flags & WE_HAVE_A_TWO_BY_TWO) != 0)
ttfunpack(f, "SSSS", &a, &b, &c, &d);
else{
a = d = 1<<14;
b = c = 0;
}
off = Bseek(f->bin, 0, 1);
h = getglyph(fs, idx, render);
if(h == nil){
ttfputglyph(g);
return nil;
}
if(mergeglyph(g, h, flags, x, y, a, b, c, d, render) < 0){
ttfputglyph(h);
ttfputglyph(g);
return nil;
}
ttfputglyph(h);
Bseek(f->bin, off, 0);
}while((flags & MORE_COMPONENTS) != 0);
g->ptorg = malloc(sizeof(TTPoint) * g->npt);
memmove(g->ptorg, g->pt, sizeof(TTPoint) * g->npt);
// g->pt[g->npt - 1].x = g->pt[g->npt - 1].x + 32 & -64;
if(render && (flags & WE_HAVE_INSTRUCTIONS) != 0){
ttfunpack(f, "w", &len);
g->nhint = len;
g->hint = mallocz(len, 1);
if(g->hint == nil)
goto err;
Bread(f->bin, g->hint, len);
ttfhint(g);
}
return g;
}
static TTGlyph *
getglyph(TTFont *fs, int glyph, int render)
{
int i;
short xmin, ymin, xmax, ymax, nc;
TTFontU *f;
TTGlyph *g;
f = fs->u;
if((uint)glyph >= f->numGlyphs){
werrstr("no such glyph %d", glyph);
return nil;
}
if(f->ginfo[glyph].loca == f->ginfo[glyph+1].loca){
return emptyglyph(fs, glyph, render);
}
if(ttfgototable(f, "glyf") < 0)
return nil;
Bseek(f->bin, f->ginfo[glyph].loca, 1);
ttfunpack(f, "wwwww", &nc, &xmin, &ymin, &xmax, &ymax);
if(nc < 0)
g = compglyph(fs, glyph, render);
else
g = simpglyph(fs, glyph, nc, render);
if(g == nil)
return nil;
g->xmin = g->pt[0].x;
g->xmax = g->pt[0].x;
g->ymin = g->pt[0].y;
g->ymax = g->pt[0].y;
for(i = 1; i < g->npt - 2; i++){
if(g->pt[i].x < g->xmin)
g->xmin = g->pt[i].x;
if(g->pt[i].x > g->xmax)
g->xmax = g->pt[i].x;
if(g->pt[i].y < g->ymin)
g->ymin = g->pt[i].y;
if(g->pt[i].y > g->ymax)
g->ymax = g->pt[i].y;
}
if(render){
g->xminpx = g->xmin >> 6;
g->xmaxpx = g->xmax + 63 >> 6;
g->yminpx = g->ymin >> 6;
g->ymaxpx = g->ymax + 63 >> 6;
}
return g;
}
TTGlyph *
ttfgetglyph(TTFont *fs, int glyph, int render)
{
TTGlyph *g;
g = getglyph(fs, glyph, render);
if(g == nil)
return nil;
g->idx = glyph;
if(render){
ttfscan(g);
g->advanceWidthpx = (g->pt[g->npt - 1].x - g->pt[g->npt - 2].x + 63) / 64;
}
setmalloctag(g, getcallerpc(&fs));
return g;
}