gimp has a old but still nicely working filter for "supernova" effect .(Filters> Lights and Shadows>Supernova)

Alas the script allow to order only 1 "stroke" and then close automatically, so use for similar effect as in this example is if not impossible a pain



to do that i had to call again the plugin and reset the preview over and over ,again and again
the idea was add much more lights but was too boring, after a few i gave up

Now would be possible

add a "Apply" function/button , working exactly as "apply " in gmic :

the command is executed BUT the filter remain open, ready for a new command , ...

maybe a simple change but would give much more flexibility to the filter
(even more if calling from GAP for animated effect ...Could you image the possibilities? )

Since Nova is a C plugin it would have to be re compiled after it was edited to except the new command.
I don't think it is possible without a bit of C knowledge and a re compile of GIMP itself.

You could ask the devs to add it in for next release on GIT.

I bet it would be easier to re write in Python with a preview.

I don't think compile would be a problem and the change i propose is really simple :

should be a C command in the last line with the function "render and close" , and that is what happen clicking OK
BUT may be another with function "render, don't close the gui" allowing to set new coordinates and or change colour and render again

Now my intuition may be insufficient to try without knowing C (and i don't know C ), nevertheless doesn't look much more complex that replace hardcoded values , and that somehow i did that even without knowing any C.

But i was hoping that somebody here with a minimal C knowledge could give a glimpse to the code to see if could be done without too much effort

About a python plugin may be fine but that filter need a accurate preview ,not sure if a similar preview would be possible with py plugin

...and again i can't bet on it, would be at least impolite define easy something i can't do without help (well i didn't try but i fear lnot easy FOR ME), but maybe is not harder then edit the last line of the original code.

You simply just want a new value "Apply the effect" but keep the plugin open correct?
So you can apply it as many times as needbe.

Why not just go to Filters>Repeat Last? (Shift+Ctrl+F) Or do you want to change the parameters each time?

Yes , exactly

Why not just go to Filters>Repeat Last? (Shift+Ctrl+F) Or do you want to change the parameters each time?

You already answer yourself:
repeat last will be pointless because will exactly repeat last
Instead i need to change the place , and i may also need to modify the other parameters

Maybe there is a gmic filter close to "supernova" ?
I already browsed the "lights and shadows" submenu but maybe i didn't notice some possibility...or maybe there is something adapt but in another submenu

That will solve for me, nevertheless i am convinced that a "apply" option would be a cool improvement ... but again a enhancement request to the dev without propose a patch look hopeless:
Thinking better, i didn't try gimp 2.9 yet, did you ? Maybe in 2.9 supernova was "ported " to Gegl ?