Hugin doesn't allow make to skip nona.

Unfortunately the Hugin Makefile system only supports restarting if you stitch on the command-line. The GUI tools always create new temporary .pto project and Makefile files every time they stitch, so this forces make to recreate everything for everyt stitch.

New FAQ: http://wiki.panotools.org/Hugin_FAQ#Makefile_based_stitching_process

Would it be possible to add a "resume stitch" functionality in the GUI? Or is this prevented by the random nature of the temporary files used for the stitch?

The pto file names are obviously generated with some "mstemp" function. That's all fine and dandy, but how about the following? We do the random filename thingy once per session (reinitialize on loading a new project?). Now we have a fixed filename pto file and Makefile.

Now for the dependency, instead of specifying "project.pto" for the nona steps we specify .mapping_of_image_0000_changed . We initialize, this when we first write the pto file, and when we later change things, we check all parameters that influence the nona step. If none of them changed, we don't update the timestamp on that file. If any of them changed, we touch the file, so that nona will run again.

We could do less "hacking" and more "let make do its job" if we extract the minimal PTO file for nona to work with for say image1.

In my case, for image 0 that would look like:
p f2 w4000 h1520 v200 E15.3667 R0 S30,3987,86,978 n"TIFF_m c:NONE r:CROP"
i w3872 h2592 f0 v19.4308886983727 Ra0 Rb0 Rc0 Rd0 Re0 Eev15.3666636524199 Er1 Eb1 r1.28847308425683 p0.0174682245138073 y-93.1233672191193 TrX0 TrY0 TrZ0 j0 a0 b0 c0 d0 e0 g0 t0 Va1 Vb0 Vc0 Vd0 Vx0 Vy0 Vm5 u10 n"DSC05514.JPG"

Next we compare it bit-for-bit with the older version of the simplified pto file. If they are the same, don't update the old version. If they are different, we replace the old version...