equations for vignette filter

[formerphysicist]

I'm not currently a Gimp user, but I'd like to know the equations used for the vignette filter. Are they anywhere in the documentation, or just buried in the source code somewhere?

[rich2005]

The current version Gimp 2.10 uses a GEGL (see http://gegl.org/) operation for creating a vignette. The page for describing the feature is http://gegl.org/operations/gegl-vignette.html and bottom of that page, a link to the code.

In earlier versions of Gimp a vignette effect can be 'hand-made' usually by filling a fuzzy selection or application of a gradient in a layermask.

You might get more information by subscribing to one of the mailing lists https://www.gimp.org/mail_lists.html

[formerphysicist]

Thank you.