Re: Some NS port changes

[Alan Third]

On Sun, Jan 20, 2019 at 06:11:17AM +0000, Zhang Haijun wrote:
> There are still too many flickers on macOS 10.13.6.
> 
> Steps to reproduce:
> 1. emacs -Q
> 2. (setq redisplay-dont-pause nil)
> 3. Select text across lines with touchpad
> 
> I can see blanks and then refreshing, sometimes just a blank retangle without 
> refreshing.

FWIW that’s exactly what I would expect to happen with that setting
set to nil. We can’t really stop the NS toolkit trying to update the
screen, but if you pause redisplay part‐way through then it’s not
going to be able to update the areas already marked as needing
redrawn.

Once it’s tried to redraw those areas, it marks them as drawn whether
it was succesful or not, so the next time round they will be ignored.
There’s not very much I can do about that.

What’s the use‐case for setting this variable?
-- 
Alan Third