Re: Pixel-based display functions

[Eli Zaretskii]

> Date: Sat, 07 Feb 2015 13:28:18 +0100
> From: martin rudalics <address@hidden>
> CC: address@hidden, address@hidden
> 
>  >> (2) For each cell put the text in a buffer and show the buffer in a
>  >>       window.
>  >
>  > I thought Lars didn't want to flash display of such windows.
> 
> How comes we'd flash them?  He would obviously restore the window
> configuration before the next redisplay.

Then how to interpret "show the buffer" in your text above?

>  > Doesn't posn-at-point and end-of-visual-line already provide the means
>  > to get this information?
> 
> The latter calls `vertical-motion' so this should work indeed.  But does
> `vertical-motion' have to go back to the beginning of a logical line
> when it's broken into several visual lines?

Yes, it does.  There's no other place where the display engine can
_know_ that the X coordinate is zero.

> This would mean that we'd always have to rescan from the beginning
> of the logical line for each visual line break

Yes.