[hackers] [dmenu][patch] Improve speed of drw_text when provided with large strings

From: <m_AT_milesalan.com>
Date: Sat, 7 Aug 2021 21:34:35 -0400

From: Miles Alan <m_AT_milesalan.com>

Calculates len & ew in drw_font_getexts loop by incrementing instead of
decrementing; as such avoids proportional increase in time spent in loop
based on provided strings size.

---
 drw.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drw.c b/drw.c
index 4cdbcbe..9c39086 100644
--- a/drw.c
+++ b/drw.c
_AT_@ -310,8 +310,11 @@ drw_text(Drw *drw, int x, int y, unsigned int w, unsigned int h, unsigned int lp
 		if (utf8strlen) {
 			drw_font_getexts(usedfont, utf8str, utf8strlen, &ew, NULL);
 			/* shorten text if necessary */
-			for (len = MIN(utf8strlen, sizeof(buf) - 1); len && ew > w; len--)
-				drw_font_getexts(usedfont, utf8str, len, &ew, NULL);
+			if (ew > w)
+				for (ew = 0, len = 0; ew < w - lpad * 2 && len < MIN(utf8strlen, sizeof(buf) - 1); len++)
+					drw_font_getexts(usedfont, utf8str, len, &ew, NULL);
+			else
+				len = MIN(utf8strlen, sizeof(buf) - 1);
 
 			if (len) {
 				memcpy(buf, utf8str, len);
-- 
2.30.2

Received on Sun Aug 08 2021 - 03:34:35 CEST