Re: [Gegl-developer] gegl-gtk

[Hendrik Boom <hendrik topoi pooq com>]

On Tue, Jul 03, 2012 at 01:28:38AM +0200, rassahah googlemail com wrote:
> Jon Nordby <jononor gmail com> wrote:
> > CC'ing the GEGL mailing list, since there may be others interested.
> >
> > Hi Isaac,
> >
> > glad to hear gegl-gtk was useful to you. I will try to check our your
> > node editor work soon.
> >
> > What exactly is the issue with nodes with infinite bounds? I have not
> > tested myself. Rendering of gegl:checkerboard sounds like some that
> > should just-work, so I'd be happy to accept patches if it does not.
>
>
> I think the problem here is that a program like this:
>
>     #include <gegl.h>
>     int main (int argc, char **argv)
>     {
>       gegl_init (&argc, &argv);
>       GeglNode *a = gegl_node_new ();
>       gegl_node_set (a, "operation", "gegl:color", 0);
>       gegl_node_process (a);
>     }
>
> does not terminate. It creates a single color node and tries to
> gegl_node_process() it.  But because the color node produces an infinite
> (virtual) image, the process node needs an infinitely long time to
> process it. Or at least this is the way i understand it. In its way,
> at least it is logical.
>
> I think the problem here is not the process functionality, but the API;
> the function gegl_node_process() does not have an error return value,
> so it practically must not fail, and so it has to take the long path
> of processing for all eternity (or until it runs out of  memory, whatever
> happens first).

It almost looks as if there needs to be som kind of bounding box to 
limit the processing to the part that might potentially be visible...
Not sure how consistent that would be to the rest og gegl, though.

-- hendrik