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From: Eli Zaretskii <eliz@gnu.org>
To: help-gnu-emacs@gnu.org
Subject: Re: Correct way to implement `pixel-point-and-height-at-unseen-line'?
Date: Tue, 14 Dec 2021 16:26:01 +0200	[thread overview]
Message-ID: <835yrrl0ue.fsf@gnu.org> (raw)
In-Reply-To: <871r2fthzg.fsf@yahoo.com> (message from Po Lu on Tue, 14 Dec 2021 21:48:35 +0800)

> From: Po Lu <luangruo@yahoo.com>
> Cc: help-gnu-emacs@gnu.org
> Date: Tue, 14 Dec 2021 21:48:35 +0800
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > Did you try something like this:
> >
> >   (save-excursion
> >     (goto-char (window-start))
> >     (vertical-motion (- (ceiling N (frame-char-height))))
> >     (point))
> >
> > where N is your number of pixels?
> 
> That won't always work correctly with lines of different height: for
> example, if the line above start is smaller than the default character
> height of the frame, the number of lines by which to move upwards could
> be too small.

But if you always need the line before window-start, i.e. use N = 1,
then why is that a problem?



  reply	other threads:[~2021-12-14 14:26 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <87pmq1wag9.fsf.ref@yahoo.com>
2021-12-13  1:38 ` Correct way to implement `pixel-point-and-height-at-unseen-line'? Po Lu
2021-12-13  2:20   ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-12-13  2:49     ` Po Lu
2021-12-13  3:04       ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-12-13  3:18         ` Po Lu
2021-12-13 23:41           ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-12-14  0:41             ` Po Lu
2021-12-13 14:32   ` Eli Zaretskii
2021-12-14  0:41     ` Po Lu
2021-12-14 13:30       ` Eli Zaretskii
2021-12-14 13:48         ` Po Lu
2021-12-14 14:26           ` Eli Zaretskii [this message]
2021-12-15  0:40             ` Po Lu
2021-12-15 13:11               ` Eli Zaretskii

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