Hi,
some time has gone since my last plug-in port to GEGL. I would like to know if some reflections has already been made concerning some technical issues that made several plug-ins' ports problematic :

1. Plug-ins that enlarge (or reduce) the drawable size

Currently, Gimp does not take into account the resulting output buffer extent of the gegl operation.

- Filters > Light and Shadow > Drop shadow - Filters > Map > Tile
- Filters > Distorts > Curve bend

2. Plug-ins that produce a new image (may be optional)

Should these plug-ins stay gimp plug-ins (to be able to create a new image), and use a gegl graph in them to apply the related operation ?

- Filters > Map > Tile - Colors > Info > Smooth palette

3. Plug-ins that use GimpGradient

Being able to give a GimpGradient parameter to a gegl op would provide the ability to modify the gradient with the gradient editor, and have on-canvas preview in the same time. I have a wip GradientMapTool that show how useful it could be : http://thomas.manni.free.fr/GimpGradientMapTool-test.webm

- Colors > Map > Gradient Map - Filters > Distorts > Pagecurl
- Filters > Light and Shadow > Gradient Flare - Filters > Render > Nature > Flame
- Filters > Render > Fractal Explorer

4. Plug-ins that use several previews / some kind of editors

Some plug-ins provide multiple small previews that simply can not be removed without losing an important aspect of their functionalities.

- Colors > Filter Pack - Filters > Render > Pattern > Qbist - Filters > Render > Fractals > Flame - Filters > Light and Shadow > Gradient Flare

Thomas Manni