git.stevedylan.dev

introduce drw_fontset_getwidth_clamp() 6be057f0

getting the width of a string is an O(n) operation, and in many cases
users only care about getting the width upto a certain number.

instead of calling drw_fontset_getwidth() and *then* clamping the
result, this patch introduces drw_fontset_getwidth_clamp() function,
similar to strnlen(), which will stop once we reach n.

the `invert` parameter was overloaded internally to preserve the API,
however library users should be calling drw_fontset_getwidth_clamp() and
not depend upon internal behavior of drw_text().

NRK · 2022-03-24 02:00 2 file(s) · +18 −2

drw.c +17 −2

		return 0;

	if (!render) {
		w = ~w;
		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);


					if (ew + tmpw > w) {
						overflow = 1;
						utf8strlen = ellipsis_len;
						/* 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;

	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.h +1 −0

Fnt *drw_fontset_create(Drw* drw, const char *fonts[], size_t fontcount);
void drw_fontset_free(Fnt* set);
unsigned int drw_fontset_getwidth(Drw *drw, const char *text);
unsigned int drw_fontset_getwidth_clamp(Drw *drw, const char *text, unsigned int n);
void drw_font_getexts(Fnt *font, const char *text, unsigned int len, unsigned int *w, unsigned int *h);

/* Colorscheme abstraction */

268	268		return 0;
269	269
270	270		if (!render) {
271		-	w = ~w;
	271	+	w = invert ? invert : ~invert;
272	272		} else {
273	273		XSetForeground(drw->dpy, drw->gc, drw->scheme[invert ? ColFg : ColBg].pixel);
274	274		XFillRectangle(drw->dpy, drw->drawable, drw->gc, x, y, w, h);

300	300
301	301		if (ew + tmpw > w) {
302	302		overflow = 1;
303		-	utf8strlen = ellipsis_len;
	303	+	/* called from drw_fontset_getwidth_clamp():
	304	+	* it wants the width AFTER the overflow
	305	+	*/
	306	+	if (!render)
	307	+	x += tmpw;
	308	+	else
	309	+	utf8strlen = ellipsis_len;
304	310		} else if (curfont == usedfont) {
305	311		utf8strlen += utf8charlen;
306	312		text += utf8charlen;

395	401		if (!drw \|\| !drw->fonts \|\| !text)
396	402		return 0;
397	403		return drw_text(drw, 0, 0, 0, 0, 0, text, 0);
	404	+	}
	405	+
	406	+	unsigned int
	407	+	drw_fontset_getwidth_clamp(Drw drw, const char text, unsigned int n)
	408	+	{
	409	+	unsigned int tmp = 0;
	410	+	if (drw && drw->fonts && text && n)
	411	+	tmp = drw_text(drw, 0, 0, 0, 0, 0, text, n);
	412	+	return MIN(n, tmp);
398	413		}
399	414
400	415		void

35	35		Fnt drw_fontset_create(Drw drw, const char *fonts[], size_t fontcount);
36	36		void drw_fontset_free(Fnt* set);
37	37		unsigned int drw_fontset_getwidth(Drw drw, const char text);
	38	+	unsigned int drw_fontset_getwidth_clamp(Drw drw, const char text, unsigned int n);
38	39		void drw_font_getexts(Fnt font, const char text, unsigned int len, unsigned int w, unsigned int h);
39	40
40	41		/* Colorscheme abstraction */