Re: wrong cursor position reported when window margins are wide

[Eli Zaretskii]

> From: Joost Kremers <address@hidden>
> Cc: address@hidden
> Date: Tue, 28 Feb 2017 21:41:13 +0100
> 
> 
> On Tue, Feb 28 2017, Eli Zaretskii wrote:
> >> From: Joost Kremers <address@hidden>
> >> Date: Tue, 28 Feb 2017 15:01:22 +0100
> >> It seems that when the window margins of an Emacs window are 
> >> non-nil, the cursor position is reported incorrectly, resulting 
> >> in 
> >> the input box being displayed in the wrong place.
> >> 
> >> The original bug report is here:
> >> 
> >> <https://github.com/joostkremers/visual-fill-column/issues/25#issuecomment-281844388>
> >> 
> >> There are screen shots that illustrate the problem. (Scroll 
> >> down a 
> >> bit for screen shots with `emacs -Q'.)
> >
> > Sorry, I couldn't understand what is meant by "cursor position
> > reporting".  Could you clarify, 
> 
> Honestly, I'm in way over my head here, so I'm mainly going by 
> this FAQ on the Fcitx site:
> 
> https://fcitx-im.org/wiki/FAQ#Cursor_Following_problem
> 
> which admittedly doesn't provide much info, either. Basically, 
> from what I gather, Fcitx and ibus and similar input methods pop 
> up an input box that follows the text cursor as you type. In order 
> to do so, they need to know the absolute position of the text 
> cursor on the screen. And in order to be able to determine 
> (calculate?) this position, they need some info from the windowing 
> system, which in turn receives this info from the active 
> application.

But we must know at least what Emacs features are used to get the
cursor position info.  Otherwise, I don't see how we can investigate
this issue, nor even that it's Emacs's fault.