Re: Question about display engine

[Ergus]

Sorry Eli I still don't see anything clear. It seems that only you have
enough knowledge to understand how this solution may work. Because I am
missing a lot of details.

I will actually stop trying, because I can't implement something I don't
understand how it works and I am wasting a precious amount of time.


On Thu, Aug 29, 2019 at 09:28:55PM +0300, Eli Zaretskii wrote:
> > Date: Wed, 28 Aug 2019 20:19:58 +0200
> > From: Ergus <address@hidden>
> > Cc: address@hidden, address@hidden
> >
> > >> 1) Base face sets background and extend; and face sets only background.
> > >
> > >The background of the base face will be extended.
> > >
> >
> > But AFAIU the actual merging rules now will create a new face (if not
> > there already) that will have the new background
>
> No.  At the point which we are discussing, only background of faces
> which have the :extend bit set get merged.  So the background of a
> face without that bit will simply not get merged.
>
> You will probably need to write a variant of merge_face_ref (or add an
> extra argument to the existing function) such that background color
> attribute of a face is not merged unless the :extend bit of the face
> is set; and similar for underline and other relevant attributes we
> discussed.