dickmenu/drw.c
NRK 22511c41d5 drw_text: improve performance when there's no match
this was the last piece of the puzzle, the case where we can't find any
font to draw the codepoint.

in such cases, we use XftFontMatch() which is INSANELY slow. but that's
not the real problem. the real problem was we were continuously trying
to match the same thing over and over again.

this patch introduces a small cache, which keeps track a couple
codepoints for which we know we won't find any matches.

with this, i can dump lots of emojies into dmenu where some of them
don't have any matching font, and still not have dmenu lag insanely or
FREEZE completely when scrolling up and down.

this also improves startup time, which will of course depend on the
system and all installed fonts; but on my system and test case i see the
following startup time drop:

before -> after
60ms   -> 34ms
2022-03-25 22:49:07 +01:00

463 lines
11 KiB
C

/* See LICENSE file for copyright and license details. */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <X11/Xlib.h>
#include <X11/Xft/Xft.h>
#include "drw.h"
#include "util.h"
#define UTF_INVALID 0xFFFD
#define UTF_SIZ 4
static const unsigned char utfbyte[UTF_SIZ + 1] = {0x80, 0, 0xC0, 0xE0, 0xF0};
static const unsigned char utfmask[UTF_SIZ + 1] = {0xC0, 0x80, 0xE0, 0xF0, 0xF8};
static const long utfmin[UTF_SIZ + 1] = { 0, 0, 0x80, 0x800, 0x10000};
static const long utfmax[UTF_SIZ + 1] = {0x10FFFF, 0x7F, 0x7FF, 0xFFFF, 0x10FFFF};
static long
utf8decodebyte(const char c, size_t *i)
{
for (*i = 0; *i < (UTF_SIZ + 1); ++(*i))
if (((unsigned char)c & utfmask[*i]) == utfbyte[*i])
return (unsigned char)c & ~utfmask[*i];
return 0;
}
static size_t
utf8validate(long *u, size_t i)
{
if (!BETWEEN(*u, utfmin[i], utfmax[i]) || BETWEEN(*u, 0xD800, 0xDFFF))
*u = UTF_INVALID;
for (i = 1; *u > utfmax[i]; ++i)
;
return i;
}
static size_t
utf8decode(const char *c, long *u, size_t clen)
{
size_t i, j, len, type;
long udecoded;
*u = UTF_INVALID;
if (!clen)
return 0;
udecoded = utf8decodebyte(c[0], &len);
if (!BETWEEN(len, 1, UTF_SIZ))
return 1;
for (i = 1, j = 1; i < clen && j < len; ++i, ++j) {
udecoded = (udecoded << 6) | utf8decodebyte(c[i], &type);
if (type)
return j;
}
if (j < len)
return 0;
*u = udecoded;
utf8validate(u, len);
return len;
}
Drw *
drw_create(Display *dpy, int screen, Window root, unsigned int w, unsigned int h)
{
Drw *drw = ecalloc(1, sizeof(Drw));
drw->dpy = dpy;
drw->screen = screen;
drw->root = root;
drw->w = w;
drw->h = h;
drw->drawable = XCreatePixmap(dpy, root, w, h, DefaultDepth(dpy, screen));
drw->gc = XCreateGC(dpy, root, 0, NULL);
XSetLineAttributes(dpy, drw->gc, 1, LineSolid, CapButt, JoinMiter);
return drw;
}
void
drw_resize(Drw *drw, unsigned int w, unsigned int h)
{
if (!drw)
return;
drw->w = w;
drw->h = h;
if (drw->drawable)
XFreePixmap(drw->dpy, drw->drawable);
drw->drawable = XCreatePixmap(drw->dpy, drw->root, w, h, DefaultDepth(drw->dpy, drw->screen));
}
void
drw_free(Drw *drw)
{
XFreePixmap(drw->dpy, drw->drawable);
XFreeGC(drw->dpy, drw->gc);
drw_fontset_free(drw->fonts);
free(drw);
}
/* This function is an implementation detail. Library users should use
* drw_fontset_create instead.
*/
static Fnt *
xfont_create(Drw *drw, const char *fontname, FcPattern *fontpattern)
{
Fnt *font;
XftFont *xfont = NULL;
FcPattern *pattern = NULL;
if (fontname) {
/* Using the pattern found at font->xfont->pattern does not yield the
* same substitution results as using the pattern returned by
* FcNameParse; using the latter results in the desired fallback
* behaviour whereas the former just results in missing-character
* rectangles being drawn, at least with some fonts. */
if (!(xfont = XftFontOpenName(drw->dpy, drw->screen, fontname))) {
fprintf(stderr, "error, cannot load font from name: '%s'\n", fontname);
return NULL;
}
if (!(pattern = FcNameParse((FcChar8 *) fontname))) {
fprintf(stderr, "error, cannot parse font name to pattern: '%s'\n", fontname);
XftFontClose(drw->dpy, xfont);
return NULL;
}
} else if (fontpattern) {
if (!(xfont = XftFontOpenPattern(drw->dpy, fontpattern))) {
fprintf(stderr, "error, cannot load font from pattern.\n");
return NULL;
}
} else {
die("no font specified.");
}
/* Do not allow using color fonts. This is a workaround for a BadLength
* error from Xft with color glyphs. Modelled on the Xterm workaround. See
* https://bugzilla.redhat.com/show_bug.cgi?id=1498269
* https://lists.suckless.org/dev/1701/30932.html
* https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=916349
* and lots more all over the internet.
*/
FcBool iscol;
if(FcPatternGetBool(xfont->pattern, FC_COLOR, 0, &iscol) == FcResultMatch && iscol) {
XftFontClose(drw->dpy, xfont);
return NULL;
}
font = ecalloc(1, sizeof(Fnt));
font->xfont = xfont;
font->pattern = pattern;
font->h = xfont->ascent + xfont->descent;
font->dpy = drw->dpy;
return font;
}
static void
xfont_free(Fnt *font)
{
if (!font)
return;
if (font->pattern)
FcPatternDestroy(font->pattern);
XftFontClose(font->dpy, font->xfont);
free(font);
}
Fnt*
drw_fontset_create(Drw* drw, const char *fonts[], size_t fontcount)
{
Fnt *cur, *ret = NULL;
size_t i;
if (!drw || !fonts)
return NULL;
for (i = 1; i <= fontcount; i++) {
if ((cur = xfont_create(drw, fonts[fontcount - i], NULL))) {
cur->next = ret;
ret = cur;
}
}
return (drw->fonts = ret);
}
void
drw_fontset_free(Fnt *font)
{
if (font) {
drw_fontset_free(font->next);
xfont_free(font);
}
}
void
drw_clr_create(Drw *drw, Clr *dest, const char *clrname)
{
if (!drw || !dest || !clrname)
return;
if (!XftColorAllocName(drw->dpy, DefaultVisual(drw->dpy, drw->screen),
DefaultColormap(drw->dpy, drw->screen),
clrname, dest))
die("error, cannot allocate color '%s'", clrname);
}
/* Wrapper to create color schemes. The caller has to call free(3) on the
* returned color scheme when done using it. */
Clr *
drw_scm_create(Drw *drw, const char *clrnames[], size_t clrcount)
{
size_t i;
Clr *ret;
/* need at least two colors for a scheme */
if (!drw || !clrnames || clrcount < 2 || !(ret = ecalloc(clrcount, sizeof(XftColor))))
return NULL;
for (i = 0; i < clrcount; i++)
drw_clr_create(drw, &ret[i], clrnames[i]);
return ret;
}
void
drw_setfontset(Drw *drw, Fnt *set)
{
if (drw)
drw->fonts = set;
}
void
drw_setscheme(Drw *drw, Clr *scm)
{
if (drw)
drw->scheme = scm;
}
void
drw_rect(Drw *drw, int x, int y, unsigned int w, unsigned int h, int filled, int invert)
{
if (!drw || !drw->scheme)
return;
XSetForeground(drw->dpy, drw->gc, invert ? drw->scheme[ColBg].pixel : drw->scheme[ColFg].pixel);
if (filled)
XFillRectangle(drw->dpy, drw->drawable, drw->gc, x, y, w, h);
else
XDrawRectangle(drw->dpy, drw->drawable, drw->gc, x, y, w - 1, h - 1);
}
int
drw_text(Drw *drw, int x, int y, unsigned int w, unsigned int h, unsigned int lpad, const char *text, int invert)
{
int i, ty, ellipsis_x = 0;
unsigned int tmpw, ew, ellipsis_w = 0, ellipsis_len, ellipsis_width;
XftDraw *d = NULL;
Fnt *usedfont, *curfont, *nextfont;
int utf8strlen, utf8charlen, render = x || y || w || h;
long utf8codepoint = 0;
const char *utf8str;
FcCharSet *fccharset;
FcPattern *fcpattern;
FcPattern *match;
XftResult result;
int charexists = 0, overflow = 0;
/* keep track of a couple codepoints for which we have no match. */
enum { nomatches_len = 64 };
static struct { long codepoint[nomatches_len]; unsigned int idx; } nomatches;
if (!drw || (render && !drw->scheme) || !text || !drw->fonts)
return 0;
if (!render) {
w = invert ? invert : ~invert;
} else {
XSetForeground(drw->dpy, drw->gc, drw->scheme[invert ? ColFg : ColBg].pixel);
XFillRectangle(drw->dpy, drw->drawable, drw->gc, x, y, w, h);
d = XftDrawCreate(drw->dpy, drw->drawable,
DefaultVisual(drw->dpy, drw->screen),
DefaultColormap(drw->dpy, drw->screen));
x += lpad;
w -= lpad;
}
usedfont = drw->fonts;
drw_font_getexts(usedfont, "...", 3, &ellipsis_width, NULL);
while (1) {
ew = ellipsis_len = utf8strlen = 0;
utf8str = text;
nextfont = NULL;
while (*text) {
utf8charlen = utf8decode(text, &utf8codepoint, UTF_SIZ);
for (curfont = drw->fonts; curfont; curfont = curfont->next) {
charexists = charexists || XftCharExists(drw->dpy, curfont->xfont, utf8codepoint);
if (charexists) {
drw_font_getexts(curfont, text, utf8charlen, &tmpw, NULL);
if (ew + ellipsis_width <= w) {
/* keep track where the ellipsis still fits */
ellipsis_x = x + ew;
ellipsis_w = w - ew;
ellipsis_len = utf8strlen;
}
if (ew + tmpw > w) {
overflow = 1;
/* called from drw_fontset_getwidth_clamp():
* it wants the width AFTER the overflow
*/
if (!render)
x += tmpw;
else
utf8strlen = ellipsis_len;
} else if (curfont == usedfont) {
utf8strlen += utf8charlen;
text += utf8charlen;
ew += tmpw;
} else {
nextfont = curfont;
}
break;
}
}
if (overflow || !charexists || nextfont)
break;
else
charexists = 0;
}
if (utf8strlen) {
if (render) {
ty = y + (h - usedfont->h) / 2 + usedfont->xfont->ascent;
XftDrawStringUtf8(d, &drw->scheme[invert ? ColBg : ColFg],
usedfont->xfont, x, ty, (XftChar8 *)utf8str, utf8strlen);
}
x += ew;
w -= ew;
}
if (render && overflow)
drw_text(drw, ellipsis_x, y, ellipsis_w, h, 0, "...", invert);
if (!*text || overflow) {
break;
} else if (nextfont) {
charexists = 0;
usedfont = nextfont;
} else {
/* Regardless of whether or not a fallback font is found, the
* character must be drawn. */
charexists = 1;
for (i = 0; i < nomatches_len; ++i) {
/* avoid calling XftFontMatch if we know we won't find a match */
if (utf8codepoint == nomatches.codepoint[i])
goto no_match;
}
fccharset = FcCharSetCreate();
FcCharSetAddChar(fccharset, utf8codepoint);
if (!drw->fonts->pattern) {
/* Refer to the comment in xfont_create for more information. */
die("the first font in the cache must be loaded from a font string.");
}
fcpattern = FcPatternDuplicate(drw->fonts->pattern);
FcPatternAddCharSet(fcpattern, FC_CHARSET, fccharset);
FcPatternAddBool(fcpattern, FC_SCALABLE, FcTrue);
FcPatternAddBool(fcpattern, FC_COLOR, FcFalse);
FcConfigSubstitute(NULL, fcpattern, FcMatchPattern);
FcDefaultSubstitute(fcpattern);
match = XftFontMatch(drw->dpy, drw->screen, fcpattern, &result);
FcCharSetDestroy(fccharset);
FcPatternDestroy(fcpattern);
if (match) {
usedfont = xfont_create(drw, NULL, match);
if (usedfont && XftCharExists(drw->dpy, usedfont->xfont, utf8codepoint)) {
for (curfont = drw->fonts; curfont->next; curfont = curfont->next)
; /* NOP */
curfont->next = usedfont;
} else {
xfont_free(usedfont);
nomatches.codepoint[++nomatches.idx % nomatches_len] = utf8codepoint;
no_match:
usedfont = drw->fonts;
}
}
}
}
if (d)
XftDrawDestroy(d);
return x + (render ? w : 0);
}
void
drw_map(Drw *drw, Window win, int x, int y, unsigned int w, unsigned int h)
{
if (!drw)
return;
XCopyArea(drw->dpy, drw->drawable, win, drw->gc, x, y, w, h, x, y);
XSync(drw->dpy, False);
}
unsigned int
drw_fontset_getwidth(Drw *drw, const char *text)
{
if (!drw || !drw->fonts || !text)
return 0;
return drw_text(drw, 0, 0, 0, 0, 0, text, 0);
}
unsigned int
drw_fontset_getwidth_clamp(Drw *drw, const char *text, unsigned int n)
{
unsigned int tmp = 0;
if (drw && drw->fonts && text && n)
tmp = drw_text(drw, 0, 0, 0, 0, 0, text, n);
return MIN(n, tmp);
}
void
drw_font_getexts(Fnt *font, const char *text, unsigned int len, unsigned int *w, unsigned int *h)
{
XGlyphInfo ext;
if (!font || !text)
return;
XftTextExtentsUtf8(font->dpy, font->xfont, (XftChar8 *)text, len, &ext);
if (w)
*w = ext.xOff;
if (h)
*h = font->h;
}
Cur *
drw_cur_create(Drw *drw, int shape)
{
Cur *cur;
if (!drw || !(cur = ecalloc(1, sizeof(Cur))))
return NULL;
cur->cursor = XCreateFontCursor(drw->dpy, shape);
return cur;
}
void
drw_cur_free(Drw *drw, Cur *cursor)
{
if (!cursor)
return;
XFreeCursor(drw->dpy, cursor->cursor);
free(cursor);
}