Re: animate incredibly slow compared to 21.3

[Kim F. Storm]

Miles Bader <address@hidden> writes:

> On Wed, 9 Mar 2005 20:24:47 -0600 (CST), Luc Teirlinck
> <address@hidden> wrote:
>>    So why is `next-line' so sub-optimal?
>> 
>> It calls line-move.
>
> Er, Ok, so then why is line-move so sub-optimal?  It might be a bit
> slower than forward-line, but surely it shouldn't cause massive
> flickering or whatever, right?

It is because of the recently added auto-window-vscroll feature
(to scroll through tall images rather than jumping over them).

To make reliable judgement about the display state, line-move must 
call sit-for which does redisplay.

It would be useful to have a version of sit-for which did redisplay
_internally_ to know what the window would look like if actually
drawn, but without actually updating the display.  I guess it would be
possible to do this, but definitely not before the release.

-- 
Kim F. Storm <address@hidden> http://www.cua.dk