fix multi-preset export scaling

[zisoft]

The scaling setting needs to be read at job creation.

fixes #19983

[zisoft]

Release notes:

Fixed wrong handling of scaling factor during multi-preset export.

[TurboGit]

Looks good to me, thanks!

[DaveInDev]

thanks guys. Is there a way to test the implementation of this new feature ? Maybe in a future Night Build ?

[TurboGit]

Yes, on tomorrow nightly build.

[DaveInDev]

I can confirm that the scaling is now fixed in the nightly build. Thanks for your help.
But there is still a problem with the "on conflict / overwrite on changed" option which is not working as intended in case of multi-export : if you use the same example as in the #19983 issue that I opened (double JPEG export in separate directories), you'll see that if you modify a RAW/XMP, and you try to reexport it and automatically overwrite the 2 JPEG files, only the first JPEG export will overwrite. The second export is ignored. But both export files should be overwritten, as the original was modified.

[TurboGit]

@DaveInDev : Can you please open a new issue for this? TIA.

[zisoft]

Probably a similar cause, I will look.

[DaveInDev]

@TurboGit : I can confirm that the issue is very well documented in #15404 , but was never corrected. I already add a comment in this issue, concerning the need of checking the date of export target files versus last XMP modification for every export preset.

[zisoft]

@DaveInDev: Can you please check #20015

[DaveInDev]

By the way, it seems that there is the same problem as the scaling factor on the JPEG quality factor. On the same example as described in #19983, where you have two differents JPEG qualities, when you multi-export, only one of the qualities is taken into account (sometimes 90%, sometimes 80%, but I do not figure out the logic...). I tested it on 5.5.0+18~gb9fa7e4d34

[zisoft]

I see.

@TurboGit: This is a real mess, the export submodules get their params by reading the GUI settings. This works when using a single export, but not when running multiple export jobs in parallel.

Only an index (format_index, storage_index) is passed to the submodules in dt_control_export instead of the data stored in the preset.
So a redesign is required here.

[TurboGit]

@zisoft : I understand, I remember having seen that when looking at the code. Part of the params are read from GUI, others from config parameters. Both could change anyway. We need a redesign on all this to snapshot all parameters when starting the export and be sure only those values are read (passed to the proper routines) during the whole export process.

[zisoft]

I think I have fixed this now in #20015

The reason was that the parameter of the format submodule were read during the running export job execution, and so reading all changes which were made in the GUI instead of the preset parameters.

Now I read the parameters at job creation and pass them to the job.