Re: Overlays as an AA-tree

[Andreas Politz]

Eli Zaretskii <address@hidden> writes:

>> Do you expect redisplay performance to improve or is it your aim that it
>> does not degrade ?
>
> It should certainly not be worse, otherwise the design and
> implementation would need to be improved, IMO.  Display is a very
> important client of overlays, so it shouldn't suffer from refactoring.

I had the idea, that this centered list intuitively sounds like a good
fit for the display's requirements, i.e. usually little random access
and the center can be updated relatively cheaply while scrolling.

> I would be happy to know that performance gets better, of course.  The
> recentering of overlays, which is not a cheap operation, should no
> longer be needed, for example.
>

It definitively is not needed.  I currently trying to improve the
performance of my implementation, with some success.  

>> BTW how do you figure out which functions need attention,
>> performance-wise.

> If you mean overlay-specific functions, I can name the most important
> ones for you.  I know which ones they are because I know what the
> display engine calls in its inner loops.

I guess, I figured it out.

-ap