Masks

[rich2005]

(05-03-2023, 05:24 PM)MironW Wrote: What is the GIMP equivalent of lightroom's Linear Gradient or Radial Gradient ?

Is it a mask or just a gradient. ?  You can apply a mask to a coloured overlay or a gradient directly onto the image.

The Gimp docs about gradients: https://docs.gimp.org/en/gimp-tool-gradient.html

From your image, it might go like this
(1) Select a gradient - FG to transparent - as soon as you adjust something it becomes a custom gradient
(2) Adjust the opacity down to suit.
(3) Various color spaces
(4) Various shapes - linear / radial - see the docs.

   

You do not get the fancy lines but there is a start - mid-point - end adjustments.

Once you have it drawn in, hit the enter key and select another tool or you get the gradient tool active again.