<gegl-developer-list gnome org> wrote:
>
> For example, let's say I'm developing a gimp plugin and I'm using gegl_buffer_iterator_* to get the data. And I want to manipulate the data in profile connection space CIE xyY. I have:
If you are creating an image processing filter - and you are dealing
with a single input and output drawable, rather than doing layer or
mask management you should be creating a GEGL operation and not a GIMP
plug-in, to get benefits of auto-constructed parameter UI, as well as
future integration with non-destructive editing in GIMP. GeglBuffer is
aware of the RGB space encoding also when the set format is CIE Lab.
I think this is is more of a GIMP dev question than a GEGL dev
question though, the ways this is hooked up has improved in GIMP-2.99
(master) over 2.10 - you might be seeing the lack of support for
custom color spaces in 2.10, as it is GIMP and not GEGL that is
synchronizing any spaces between drawables in core and plug-ins.
/pippin
It is true that I might do away with a gegl operation to get the auto constructed parameter UI. But I would need more than one input image. In my mind/design, there's this main layer which would get this filter applied on, but there need to be one or two user selectable secondary layers for additional input. Is it possible to do that with the design you have in mind?
But the bigger problem is the desperate lack of any guides/tutorials, etc. I started the development in the current way simply because there's basically only one source of how to do a plugin development and that is https://developer.gimp.org/plug-ins.html. And that guide is over ten years old and I got tons of depreciated warnings etc. And I spent extremely long tracking and jumping through all gimp/gegl/babl C documentation to get to the current point where it somehow works - in sRGB only.
The only "guide" on how to create a gegl operation is https://www.wiki.gimp.org/wiki/Hacking:Porting_filters_to_GEGL and that one is extremely sparse and imho quite laughable for anyone but core gimp developers. I simply could not find any starting points on how to create a gimp filter (plug-in alike) using a gegl operations (and XML for example).
The documentation on gegl git is also more aimed towards gegl as a standalone rather then gegl in gimp.