Re: [Gimp-developer] fix gimp

[Boudewijn Rempt <boud valdyas org>]

On Wed, 27 Dec 2017, Alexandre Prokoudine wrote:

> On Thu, Dec 28, 2017 at 1:42 AM Boudewijn Rempt wrote:
>
> > This, actually, is also how Photoshop works: one Krita developer spoke to
> > a Photoshop developer during a recent conference and picked his brain...
> > Photoshop makes a copy of the image for _every_ state. Any undo state is a
> > shallow copy of the document.
>
>
> Even for gigapixel panoramas?

That's what they told us. The number of pixels shouldn't matter, since these
are shallow copies -- only when a tile is changed, the actual pixel data gets 
copied.

That reminds me -- I don't know how Gimp handles its tiles (or scanlines) but
krita has got a huge and very complicated pool and hash tables to store tiles.
In photoshop, tiles are large and stored in a plain std::vector.

-- 
Boudewijn Rempt | http://www.krita.org, http://www.valdyas.org