Requested Improve slideshow control

[Starosta]

Hello,

I would like to propose some improvements in slideshow using IrfanView. Currently, there are 2 possible options: "show all photos from the file list sequentially" and "show all photos from the file list randomly". I propose to extend it:

1. Create list of folders to show (not individual files).
2. Slideshow modes:
   1. Cycle over folders randomly, i.e. select folder from the list, and show all photos/videos from the selected folders, in "native order/sequentially" or in "random order", depending on the setting.
   2. Cycle over folders sequentially, i.e. follow the folder list, photo ordering also can be chosen "sequential/random".
   3. Full random order: show random photo from the random folder.
3. Useful extra option: limits number of photos to be shown from one folder to some pre-defined number (can be useful for big albums).

Other useful extra for slideshow:

1. Show only photos that have the same orientation as device or:
2. Option to show all photos, vertical (portrait) orientation only, horizontal (album) orientation only.
3. Support of panoramic photos: scroll such photos, left to right or right to left for horizontal, up-down/down-up for vertical.
4. Auto update list of folders, i.e. only parental folder can be specified in this way, and list of folders is autogenerated on startup.