[hackers] [dwm] Improve speed of drw_text when provided with large strings || Miles Alan

[git]

commit 716233534b35f74dba5a46ade8f1a6f8cc72fea4
Author:     Miles Alan <m...@milesalan.com>
AuthorDate: Mon Aug 9 18:24:14 2021 +0200
Commit:     Hiltjo Posthuma <hil...@codemadness.org>
CommitDate: Mon Aug 9 18:25:19 2021 +0200

    Improve speed of drw_text when provided with large strings
    
    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.

diff --git a/drw.c b/drw.c
index 4cdbcbe..9c39086 100644
--- a/drw.c
+++ b/drw.c
@@ -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);