[Feature Request] Playmode_Showcase/Demomode

[DarkBahamut162]

Is your feature request related to a problem?

Not really a problem but it would be a neat feature:

I've notice (like lately for the OutFox Serenity Volume I showcase) that there really isn't that much of a way to showcase more than two charts at once ingame.
There once was a 4-Player modification to an older StepMania 5 build but it was somewhat buggy and awkward to handle (especially setting all the keys for all 4 Players).
Something better than that would be great for not only for showcases of future OutFox Serenity Volumes but also for others as well.

There are two ways of making it happen: With Player or just AutoPlayer/AutoPlayerCPU for everything.

Describe the solution you'd like

The first option would be "With Player":
Select a song and difficulty as usual, but it would go into the "two part selection" for the selection of additionally to show off charts to played by the AutoPlayer/CPUs.
It might turn itself into a "three part selection" by checking if one would like to showcase the x amount of other difficulties previously selected for the AutoPlayer/CPUs (and maybe showing off the remaining un-selected options).

The gameplay might have two options of showing stuff off:

• One would be all of them side by side in difficulty order and the player would then be moved to the selected difficulty's position in it (while maybe making it obvious to the player where they are if they are confused about the display).
• The other one would be one side being the Player and on the other side there being all the selected AutoPlayers/CPUs (This might even be an idea for the online multiplayer, once it gets to that stage).

Describe alternatives you've considered

The second option would be "Without Player"
So the selection would already go into the "second part" from before from the very start.
It wouldn't/shouldn't even continue on to the gameplay with 0 charts selected (while also asking if they want their selection while others are still un-selected, like mentioned above).

For the gameplay, this time, only the first option would exist: All of them side by side, going into two rows if everything gets too squashed with too many difficulties (especially within modes with more arrows/keys taking up more space | This information also counts for the first option, of course).

Additional context

I'm not very sure if it would then also be possible to showcase more than one style at once?
Not sure if the engine is even versatile/powerful enough for that.