bug#32932: 27.0.50; render bugs on macOS Mojave

[Boris Buliga]

Alan,

Thank you for the patch. I will also give it a try because I experience flickering from time to time.

On Mon, 29 Oct 2018 at 18:09, Alan Third <alan@idiocy.org> wrote:

On Sun, Oct 28, 2018 at 07:18:04PM -0700, Aaron Jensen wrote:
> On October 24, 2018 at 3:42:47 AM, Alan Third
> (alan@idiocy.org(mailto:alan@idiocy.org)) wrote:
>
> > I’ve pushed a slight variant of this change to emacs-26. I’ve
> > witnessed a very rare flicker of the modeline and the line containing
> > the cursor in other windows while scrolling, but I can’t replicate it
> > consistently.
>
> I am definitely seeing the flicker on the current line. It happens
> occasionally when my emacs is idle (probably not truly idle). I see it
> sometimes when I tell emacs to do something that is a thread blocking
> operation (like loading some autoloaded lisp for the first time). It’s
> as if it clears the current line and then immediately blocks the
> rendering thread before it gets a chance to rerender the line. As soon
> as Emacs is done doing whatever it was doing, the line rerenders.
>
> No clue if that helps, but if there’s anything you want to try, I’ll
> be able to let you know if it fixes it :)

One more go. I don’t think I’ve seen the cursor line flicker after
installing this.

Simply, all I’ve done is stop making it redraw the entire line the
cursor is on. That should stop any flicker of the line text caused by
redrawing the cursor, but won’t stop any flicker of the cursor itself,
although I’ve not seen it flicker.

There’s a bit more in here to do with drawing the fringe bitmaps,
because that was the only other place ns_clip_to_row was being used,
so I’ve removed it from there too.
--
Alan Third

--

Cheers,

Boris