Re: Emacs terminology (not again!?)

[David Kastrup]

Eli Zaretskii <address@hidden> writes:

>> From: David Kastrup <address@hidden>
>> Date: Sat, 18 Jan 2014 09:55:13 +0100
>> 
>> > It is a UI design decision in Emacs to always show point on screen.
>> > But nothing prevents us from writing a mode that leaves point off
>> > screen, or even abandoning that decision if we want (and I'm not
>> > saying we do).  The infrastructure is there, check out the vscroll
>> > thingy and window-vscroll.
>> 
>> That scrolls "graphically"
>
> Yes, I don't see how this is important for the issue at hand.  On a
> text terminal, each character counts as a single pixel.
>
>> (no idea whether it works on text terminals):
>
> It doesn't currently, but that's just because no one bothered to
> implement that.
>
>> basically it displaces your screen window by a given distance.
>
> Yes.
>
>> There is no concept of a "window start" in terms of a text position
>> that can move away from point
>
> A window start is just a buffer position, so I'm not following your
> argument here.
>
>> and no real way to implement that.
>
> ??? Why not?  Perhaps you mean no way to implement that easily, or
> maybe in Lisp alone.

If the task is "let the window start with the given buffer position even
if this makes point go off-screen", a reasonably simple task
description, window-vscroll does not seem like a useful tool for that.

-- 
David Kastrup