bug#32932: 27.0.50; render bugs on macOS Mojave

[Alan Third <alan@idiocy.org>]

On Fri, Oct 19, 2018 at 09:26:56AM -0700, Aaron Jensen wrote:
> On October 16, 2018 at 12:04:19 PM, Aaron Jensen
> (aaronjensen@gmail.com(mailto:aaronjensen@gmail.com)) wrote:
> > The other thing that I see sometimes and I don’t know if it is
> > related is that the menu bar flickers. I don’t know how Emacs
> > could do that so it could be an OS level bug, but I wanted to
> > mention it in case it jogged any ideas.

Well, the GNUstep version flickers the menu two or three times every
repaint. I think it’s because there’s some code forcing an update of
the menus to work around a problem with them not updating correctly
when required.

The menus definitely need a fair bit of work done to them. I think
they’re a little overly complex, but that may have been done to match
up with how Emacs handles them. I need to investigate it more.

> I definitely still see render errors. I don’t have a way to reproduce
> them, but I was able to capture a screenshot:
> 
> https://cl.ly/9065281385cf/Image%202018-10-19%20at%209.20.34%20AM.png

Does it actually look like that? With the strange blocks? It looks
like there’s some weird resizing/resampling thing going on...

> I believe everything was blank until I started to do next lines. Every
> line the point touched painted.

That makes sense because of how the cursor code marks entire lines as
dirty. If it was drawing correctly then I’d fix it, but there’s no
point just now.

> I still think that the patch is better than what’s on master, but it’s
> not perfect just yet.

I understand Eli’s planning on a freeze for 26.2 soon, so if I’ve not
got anything better than this at that point I’ll make sure it’s
included.
-- 
Alan Third