Collapsing/expanding nodes

[joeyballentine]

Closes #2529

[RunDevelopment]

I think we should largely copy blender for this feature. They do it like this:

The main aspects I would copy from this are:

1. The collapse/expand icons. I think their icons are a lot clearer.
2. Their input/output handles are usable even when collapsed. This would make some of our nodes fully functional even when minimized.

What do you think?

[joeyballentine]

How does 2. look when there's a shit ton of handles?

[RunDevelopment]

It increases the size of the header. Quite clever.

[joeyballentine]

To be completely honest, that sounds like wayyyyy too much work to do, especially now that i've already done it this way. And not to mention our nodes are a different shape than blender's, and they have more information on them. Unless you think we should get rid of the validation marker and the disable toggle when a node is collapsed and just have the header?

[RunDevelopment]

To be completely honest, that sounds like wayyyyy too much work to do

It might not be. Since you brought up removing the footer, I tried doing that. (Didn't sound like such a bad idea.) Honestly, it looks pretty good with centered handles:

As for how this works with a lot of handles: it doesn't.

It can deal with up to 6 handles without overflowing, which should cover most nodes. And if it does overflow, it just looks a little bad, but it doesn't break anything.

The only thing I would still change is to show the status icon where there is currently empty space (where you have a placeholder icon button). But I would only show it when there is an error. No need to clutter the clean UI when we have nothing to report.

What do you think?

---

That aside, I found another minor issue: when I minimize a node with a multiline text box (e.g. text to image), the collapse toggle moves (since it is right aligned). Instead of making nodes keep the increased width, I would suggest moving the toggle to the left of the title. You can see what that looks like in the screenshots above.

[RunDevelopment]

I made a PR for my last comment: #2551

[RunDevelopment]

@joeyballentine please don't merge after #2551. There are still 2 bugs:

1. The color of minimized input handles isn't always the same as that of the real ones.
2. Node documentation has the collapse toggle, but it does nothing.

[joeyballentine]

Fixed the two bugs, should be good to go now