Re: [Gimp-developer] GIMP - flesh out a way of allowing lazy rendering?

[Øyvind Kolås <pippin gimp org>]

On Mon, Mar 4, 2013 at 9:24 PM, Joao S. O. Bueno <gwidion mpc com br> wrote:
> While GIMP 2.9 is thriving with lots of possibilities, one thing remain as fact:
> it is dead slow.

O'RLY?

I will defer to mitch whether it is wise to do this type of GIMP-wide
re-architecting as summer of code.. personally I doubt it to be a good
thing to do in particualar changing what one wants to do and adding
even more moving parts during a time of transition; instead of
focusing on profiling and optimizing what one can. We have seen much
better performance earlier in the 2.9 cycle (where things already were
making significant use of GEGL) thus there likely is some rather low
hanging fruit that could mean an order of magnitude better
performance.

Making GEGL able to lazily render previews to scaled down mipmap
levels is something that could improve display performance/layer
compositing in current GIMP but not painting nor application of
filters. It would still bring some benefit, it doesn't touch parts
which are already in significant flux and it will provide bigger
benefits in the future. Public APIs in GEGL that will be touched by
such changes (most of them at least) have already gotten additional
arguments in preparation for such changes in hope that we do not have
to break API for operations. Working on 50% 25% or 12.5% of the pixels
should already provide a significant boost in performance and doing
8bpc would not be giving comparable benefit to that.

/Ø