Re: Getting column position accounting for overlays

[Yuri D'Elia <wavexx@thregr.org>]

On 05/08/15 04:51, Eli Zaretskii wrote:
>> From: Yuri D'Elia <wavexx@thregr.org>
>> Date: Tue, 4 Aug 2015 22:01:24 +0200
>>
>> Is there a quick way (without iterating through 'display overlays) to
>> get the current column position for the displayed text?
> 
> What is "the current column position"?  How do you define a "column"
> when text can include variable-size fonts and images?
> 
> One answer to your question is posn-at-point, but I'm not sure that is
> what you want.

I expected such question ;)

I'd like the equivalent of (current-column), or character length between
(beginning-of-line) and cursor position [modulus tabs], but using the
actual displayed overlays.

I would almost have expected something to extract the visualized string
between two points, like `buffer-substring' but iterating through
overlays; but couldn't find any (did I miss it?)

(posn-col-row (posn-at-point)) "would" work, but 1) seems inefficient,
especially considering I don't care about variable-pitch fonts and 2)
doesn't work if the point is not visible.