Resizing for the nodes.

[vzarytovskii]

Hey @WilliamKarolDiCioccio, first of all, thanks for the library, I am very new to both flutter and dart, and found it not only useful to me in my small pet project, but also a great source for the learning of Flutter libraries.

I would like to contribute to it and add a resizing support for the nodes, if it's something what is desired.

I, however, am quite new to GUI/client side programming in general and flutter in particular (I'm more of a compilers person), in case if it's something you would accept as a feature, here would be my approach to pursuing it:

1. Add dimensions to the Node (+ serialization/deserialization).
2. Add certain handlers to the _NodeWidgetState, such as _handleResizeStart, _handleResizeUpdate and _handleResizeEnd to handle/set the states of the widget.
3. Set certain default constraints on the minimal size of the node/widget.
4. Allow user to configure whether resizing is enabled or disabled and whether child widgets can/shall be resized together with the container.
5. Handle/cancel other user events which can occur (like cancelling selection event when node is resizing).

Again, if it's something you see fitting in the fl_nodes, I would be happy to bite a bullet and try implementing it, and will be grateful to any pointers or things I've missed.

Thanks in advance.

[WilliamKarolDiCioccio]

Thanks @vzarytovskii, that means the world to me!

I've never noticed it was possible to do it in most node editors (I just checked with blender and UE5). Sounds like a cool feature. I'm happy to let you collaborate to this project and to give you the possibility to practice your skills. If you plan on future contributions I can add you as a collaborator.

You seem to be on the right track with all the points you've made. A recommendation, mind the input handling, the edge might overlap with the ports and the program should distinguish what to do.

If you need help don't be afraid of asking here or even on the Discord server here (not that the server was born for fl_nodes but the two projects are strictly related), also the FlutterDev community is eager to help newcomers.

On an unrelated note:

1. Would you like to tell me more about your app?
2. You're not merely "more of a compiler person", you're CompilerMan 🦸. I had this idea of building a compiler myself in the back of my mind (never got past AST) for a while now. If that ever becomes a reality I know who to bother 😂

[vzarytovskii]

Great, thanks for the feedback and kind words, I will then try to start playing with it, might just straight submit a draft of changes and just go from there.

As for app - it's pretty much a canvas with ability to create and connect nodes, with ability to "run" a computation (as part of the node, can do some data fetching, maybe some other side-effects), (re)using data from the previous nodes, etc.

It's pretty much custom node editor, but with focus on textual data.

[vzarytovskii]

Alright, I made some progress:

resize.mov

Will need to see how does it behave when:
a. Ports are involved
b. Child fields are there and whether or not they're getting resized.

After that, I will make most of things configurable, so there are no surprises for any existing consumers.

[WilliamKarolDiCioccio]

Great job 👍

Ports position are accessed using widget key global coordinates so that should always work fine.

One thing you should be aware of is the spatial hash grid mechanism and more specifically how nodes are inserted in it. To avoid unnecessary insertions I use the didUpdateWidget method as you can see here. A change in the entity state must occur to trigger the insertion so you must either add the size property to the state struct (also good for serialization) or add another check.

Hope this helps.
Let me know how things go.

[WilliamKarolDiCioccio]

Hey @vzarytovskii! How's it going? Don't worry, it's not a race. Just checking on you.

[vzarytovskii]

It's been going well. I needed to switch to some other projects, but will come back to it in the near future. I got resizing working in general, so need to rebase on the latest upstream and check it with example project.

[WilliamKarolDiCioccio]

Hi @vzarytovskii! How are you doing? Just checking on you after I got back on the project. I've received an invite for an hackathon that had to do with this.

[vzarytovskii]

Hey, thanks for checking in. All of my free time on oss was consumed by work unfortunately :( I would still like to contribute to the project, but unsure when I will be able to come back.

[WilliamKarolDiCioccio]

No worries, It isn't in the roadmap even doe it's a nice feature to have and I too abandoned the project for a while. Hope your hard work pays off 😉