GUI "cards"

Nobody has claimed this yet.

I'm trying to figure out a decent way to implement "cards", i.e. a collection of widgets representing one item, often in a list of variable number.

It looked like `groups` were my best bet.
But they're supposed to have unique id's, which is not really possible in a variably sized array.

While testing my idea, I have semi-successfully created a proof of concept, using `nk_layout_space_` and `nk_group`. I have a loop that generates three groups per "card", using the same id's each time.
Probably not a great idea.

However, I can't figure out how to colour the background of each card.

AFAICT there is no way to set the background for a group. But anyway, I really want to set the card background, which is not a single group.

I presume I could draw e.g. a rounded rectangle and then draw the other widgets on top, but I've not yet figured out how.

If anyone has suggestions of what features I could look into that would be great.

I imagine this could end up being a custom widget (layout?).

Start by reviewing the nk_layout_space_ and nk_group APIs used in the proof of concept, then inspect Nuklear's existing widget and drawing entry points. Determine whether cards require a new widget or layout capability, and define completion around rendering a variable collection of widgets with a distinct background for each card.

Written by the indexing model from the issue text.