bug#68006: 30.0.50; Image-mode speed

[Eli Zaretskii]

> From: Manuel Giraud <manuel@ledu-giraud.fr>
> Cc: stefankangas@gmail.com,  68006@debbugs.gnu.org
> Date: Thu, 04 Jan 2024 20:16:19 +0100
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > Yes, probably.  And if you are going for the simple solution, please
> > keep in mind that image-cache-eviction-delay is a global variable, and
> > the images are cached on a per-frame basis.  So if image-mode enlarges
> > image-cache-eviction-delay, it will affect all the images, not just
> > those in image-mode buffers.  One more reason why I think we should
> > provide a separate and differently managed cache for this purpose.
> 
> Ok.  Maybe we should re-use the current C cache code with a "nice"
> interface for this too.

Yes, that can be done.  But we might need to store additional
information there, like the buffer of the image, for example.