vig_optimize is not working on HDR images

[Alex Fliker]

PTO project before running vig_optimize:

https://fliker09.tk/sharedstuff/launchpad/panorama_9_ptovariable.pto

PTO file after running vig_optimize:

https://fliker09.tk/sharedstuff/launchpad/vig_optimize.pto

Source files:

https://fliker09.tk/sharedstuff/launchpad/1.hdr
https://fliker09.tk/sharedstuff/launchpad/2.hdr
https://fliker09.tk/sharedstuff/launchpad/3.hdr
https://fliker09.tk/sharedstuff/launchpad/4.hdr

vig_optimize output:

loading: 3.hdr
downscaling: 3662x5488 1831x2744 916x1372
loading: 4.hdr
downscaling: 3662x5488 1831x2744 916x1372
loading: 1.hdr
downscaling: 3662x5488 1831x2744 916x1372
loading: 2.hdr
downscaling: 3662x5488 1831x2744 916x1372
Sampling points
sampling points
extracting good points
Selected 12 points
Vignetting Optimization

Nothing suspicious, but I don't get any optimization. For comparison, autooptimiser succeeds (but I am not quite satisfied with it, but that's for another discussion).

[tmodes (tmodes)]

Fixed in repository (changesets 72a7b9b22974 and 49e4fa244293).
There were several issues which lead to this bug.