[Klug-general] gimp rotation sequence layers duplication

[Thomas Edward Groves]

Thinking about this one:
if the Gimp had the concept of a 'virtual' or 'nonexistent' pixel
that is one on which NO operation was to be carried out
then it could pad out rotations with such and avoid this kind
of mess.
Of course that would mean a new file format.
Hmm.
Probably not going to happen.

Tom

----- Original Message -----
From: Mike Evans <mike at tandem.f9.co.uk>
To: <kent at mailman.lug.org.uk>
Sent: Friday, February 05, 2016 9:45 AM
Subject: Re: [Klug-general] gimp rotation sequence layers duplication


> That's what an exponential curve looks like.  (It is an exponential
> isn't it, rather than some other geometric progression?  It's rather a
> long time ago since I had to bother with that stuff.)  Ever tried the
> game with the rice grains on a chess board?
>
> On 05/02/16 09:09, jwmartnet . wrote:
> > The extra time wasn't really noticible until the 15th layer or so and
> > still pretty quick, so I just plodded on with it. Was only in the last
> > few layers where it really got dragged down.
> >
> > On 5 February 2016 at 08:30,  <john at johnreid.it> wrote:
> >> Because of the immense size, would it not be smarter to duplicate and
rotate the original layer each time r‎ather than each subsequent, expanded
canvas?
> >>
> >> ‎Alternatively, once the image size starts to slow the system down use
Gimp's autocrop function to get the canvas size down to 500px again.
> >>
> >> I imagine that rotating a raster image that's 35,000 pixel‎ square
(over a billion pixels!) is a chunk of work for any system.
> >>
> >> Glad to see the group chatting, by the way!
> >>
> >> John
> >>
> >> Sent from my BlackBerry 10 smartphone.
> >>    Original Message
> >> From: jwmartnet .
> >> Sent: Thursday, 4 February 2016 23:07
> >> To: Kent Linux User Group - General Topics
> >> Reply To: Kent Linux User Group - General Topics
> >> Subject: Re: [Klug-general] gimp rotation sequence layers duplication
> >>
> >> Oh. The last layer is 35370 x 35370 px.
> >>
> >>
> >> On 4 February 2016 at 23:02, jwmartnet . <jwm.art.net at gmail.com> wrote:
> >>> Hi,
> >>>
> >>> Anyone know much about how the gimp does rotation? I started with a
> >>> small image < 500x500 px, and performed the following procedure:
> >>>
> >>> 1) duplicate layer
> >>> 2) rotate new layer 15 degrees
> >>> 3) duplicate rotated layer
> >>> 4) repeat from step 2
> >>>
> >>> So I've got around 21 layers now and with each layer the rotation is
> >>> taking longer and longer, about two minutes - on an i7-4790k @ 4ghz.
> >>>
> >>> Yawn.
> >>>
> >>> James.
> >> _______________________________________________
> >> Kent mailing list
> >> Kent at mailman.lug.org.uk
> >> https://mailman.lug.org.uk/mailman/listinfo/kent
> >>
> >> _______________________________________________
> >> Kent mailing list
> >> Kent at mailman.lug.org.uk
> >> https://mailman.lug.org.uk/mailman/listinfo/kent
> > _______________________________________________
> > Kent mailing list
> > Kent at mailman.lug.org.uk
> > https://mailman.lug.org.uk/mailman/listinfo/kent
>
>
> _______________________________________________
> Kent mailing list
> Kent at mailman.lug.org.uk
> https://mailman.lug.org.uk/mailman/listinfo/kent