Hi Peter!

yahvuu wrote:

Tobias Ellinghaus schrieb:
Am Mittwoch, 8. Juli 2009 schrub yahvuu:


The user sends a JPEG to a colleague for review -- takes 2 hours to render.
The image is OK, the user creates a TIFF for the print shop -- takes 2
hours again.

I think in this case, the user would be better off if he had some
control about when the rendering happens.
What about caching the rendered image? As long as nothing is changed it can be 
reused. And when anything is altered in the image it has to be rerendered 
anyway. At least if it's not possible to cache intermediate results of the 
rendering or just rerender the changed parts.

that gives a very nice solution! Some disk cache is needed by GEGL anyway,
and if that cache is persistent across sessions, unnecessary recalculations
can be mostly avoided.
What about taking the cache with you? e.g. switch to another workstation - would be cool to have an option to store the cache external too...
Personally, i wouldn't mind to assign some GBs to GIMP in order to make my
life easier. Those who do mind, could set the 'persistent cache' size to zero
in order to make shure GIMP cleans up when closing the session.
That would be fine - question is:

a) save only the final image

b) save all the results of the GEGL graph nodes during a session so that not all nodes have to be calculated if only the last one is changed...

c) create a dedicated "cache" or "proxy" node that can be assigned by the user

In case someone really needs to save the rendered bitmap together with
the composition, there's still the possibility to put that option into
the finalize command. Or something like that.
Use case?

A) I have a comp. that takes 2h to render and I want to take the cache with me because I want do do some final color adjustments with my client. If I reopen the comp and change the color node settings the rendered bitmap beomes invalid and I need another 2h to recalculate all again...

In this case I just hat to export a PNG or something like and start a new comp. to do the final color tweaks.
But that would be bad for the workflow because now I have 2 comp. to work with...

B) I've set a "GEGL "cache node" ontop of the GEGL nodes that took 2h to render and stored the "cache node" data into my Gimp comp. file. In my clients office I load the comp. into Gimp and add another GEGL color correction node ontop of the "cache node" - now I do some quick "realtime" adjustments to get the approval for the image from my client. 2h of rendering saved...

A simple prerendered cache won't save the day i think...


Danko Dolch
3D artist & compositor
Gimp-developer mailing list

Reply via email to