On Sep 22, 2004, at 10:53 AM, Øyvind Kolås wrote:
On 09/21/04 23:17:28, Øyvind Kolås wrote:
The act I call processing is called evaluating in GEGL, I feel this
is an issue where I probably have a stronger bias towards the
terminology
I have been using, both terms probably have merit, and I'll leave the
term process in gggl for the time being.
I after spending some time today looking closer at the GEGL api, I
have rediscovered more of the reasoning that it is called evaluate in
GEGL, in GEGL you are only able to evaluate a ROI (region of interest)
on a particular root node in the graph. The region of interest, and
minimal recomputation which this approach advocates is interesting,
but it has
a shortcoming.
The approach doesn't easily facilitate multiplie active sinks at the
same time, something that might be beneficial for rendering thumbnails
in the composition treeview in GIMP. The approach needed with the
current evaluation manager is to issue a seperate processing step for
each thumbnail that one wants to generate.
This isn't a limitation of the "ROI" processing concept. Ideally the
results from any particular processing is caching, and only
recalculated if something changes, the cache gets full, or it is faster
to recalculate than draw from the cache. In which case, the second,
thumbnail calculation doesn't take much extra time, since it can reuse
the results of the first, Original calculation.
--
Daniel Rogers
University of California, San Diego
Programmer/Analyst II
Department of Radiology
danrogers@xxxxxxxx
Voice: 619-543-5250