Re: Question about display engine

[Ergus]

On Mon, Sep 09, 2019 at 09:39:13AM +0200, martin rudalics wrote:
> > I fixed that, try now please (it is in savannah already).
>
> Thank you.  Works now as expected.
>
> I'm still not convinced that it is a good idea to unconditionally run
> handle_face_prop_general from extend_face_to_end_of_line.  It will
> penalize processing every line shown in a window even if no attribute
> processed is affected by a nil :extend attribute.  But if you and Eli
> think it's cleaner to do it this way, I will not object further.
>
> Thanks again, martin
Hi Martin:

I actually don't agree either... but the merge process is a destructive
operation (like a binary | ) So it means that we lost information during
the merge process and we don't have a method to know the merged faces
only with the face_id (in the general case) and mergng different faces
could produce the same result.

We can do some optimizations like condition the call if the face_id at
position is not the default face for example. Or compare with the
previous call result... but I think that only Eli can suggest which are
applicable in this case.