It worked!
Recall that I was testing to output 6 cube faces from Blender 2.8 using the super-fast Eevee render engine. Instead of 90 degrees, they covered 110 degrees so that Hugin would blend the edges.
It worked originally BUT there was a problem with the enblend program that put strange artifacts when run from the command line. Turns out that there is a newer way to use Hugin from the command line, a program called hugin_executor -BUT it didn’t allow for specifying input filenames from the command line.
Sooooo… I set up the script in Linux to copy the 6 cube sides to a scratch folder and rename them to the filename in the PTO file. Then it blends the 6 images into a fulldome master file and moves onto the next frame number in the sequence.
My script needs cleaned up a bit and it isn’t pretty to look at. But it works and I can set it going and walk away from it while it does all the work.
Now I need to test it with a variety of scene types to see how the seams turn out. Even if I can’t use this for all cases, it will still work for enough situations to have made this worth my while.
I’ll keep updating on this, and will share the scripts and make a tutorial or how-to if there is enough interest.