Subject: Re: bug#52676: 28.0.50; [PATCH] Rationalize window-text-pixel-size

From: Po Lu <[email-masked]>
Date: Tue, 21 Dec 2021 09:34:37 +0800

dick <[email-masked]> writes:

> I am sure there was a way to do what you wanted without resorting to
> what you did.  Perhaps I've been too harsh on you.  You've gotten a lot
> of poor (but earnest) counsel from emacs-devel.

None of the counsel was "poor".  If you have anything real to add to the
discussion, please quit the rhetoric and say what the problem is out
loud.

>                  (cons (car dims*)
>                        (- (cdr dims*)
>                           (save-excursion
>                             (goto-char to)
>                             (if (> (line-end-position) (line-beginning-position))
>                                 (line-pixel-height)
>                               0))))))))

There goes the part of the performance problem that change was supposed
to solve: if you take a look at `pixel-point-and-height-at-unseen-line'
in its current slow state, that is similar to what is already being done
there.  (And once again, your test simply does not work when there is a
line-prefix, unlike `pixel-point-and-height-at-unseen-line'.)

So before you come to the conclusion that it is ok to remove a change,
please take a minute to at least try to understand the logic behind that
change.