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.

1 files changed, 5 insertions, 2 deletions

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);