Allow members and methods from a `Node` as parameters of a signal in "advanced mode" of the signal connection dock

[Lazy-Rabbit-2001]

Describe the project you are working on

Any project, with signal frequently used

Describe the problem or limitation you are having in your project

Currently, only static data can be passed as parameters of a signal in the signal dock: They are bool, int, float, String, Vector2/3/4(i), Rect2(i), Transform2D/3D, Plane, Quaternion, AABB, Basis, Projection, Color, StringName, NodePath, Dictionary and Arrays(including PackedArrays), which are certain numbers.
However, as the frequency of signal connection in the editor grows, it's not sufficient to only allow the static data to be passed as parameters in the signal connection in the signal dock, but more expected to add something dynamic, like members and methods to make the signal connection more flexible in the editor.

Describe the feature / enhancement and how it helps to overcome the problem or limitation

Add two options in the advanced mode of signal dock: Extend the dock right and add two column containers: Passed-in members and Passed-in methods, by the right side of which are added two buttons: Add from Node and Remove

Describe how your proposal will work, with code, pseudo-code, mock-ups, and/or diagrams

When the button Add from Node is pressed, there will be a pop showing the node tree, and the developer can choose one node from it, after which a new pop will display, listing the members/methods of the node, and he/she can double click on the one he/she needs to add and there will be a column created, with letters in this form:

Passed-in members

Node:property Node/Node2:position:x

(The way works almost the same for passed-in methods container)

And if a user wants to remove the passed-in param, just choose the column and click Remove

Note: The order of each column is strictly mapped, which means that the order of the column is the order of the params to be passed into the connected method(s)

If this enhancement will not be used often, can it be worked around with a few lines of script?

No, because this is related to core of editor, and needs to write from source code

Is there a reason why this should be core and not an add-on in the asset library?

No, the reason is the same as the previous chapter

[AThousandShips]

While interesting as an idea the serialisation and construction of Callable and binding to them isn't trivial, and that's why they aren't available here, there's various possible issues with it

Worth investigating but it's quite complicated to handle

[Lazy-Rabbit-2001]

Closed this proposal for the limitation mentioned in the previous post. Please don't mark this as archived becasuse this post would be reopen one day the tech gets improved.

[Calinou]

Please don't mark this as archived since this proposal could be reopened in the future.

I prefer marking any proposal that hasn't been implemented as archived for organizational purposes. We can remove the label later if you decide to reopen it :slightly_smiling_face:

[Lazy-Rabbit-2001]

I came up with an idea, but not the best performance-booster: We can have something to get the memeber and callable by String or StringName in the signal connection dock, for example:

==== Passed-in Members ====
Argument1: [member's name here] (`String` or `StringName`)

==== Passed-in Methods ====
Argument1: [method's name here] (Same)

Then at the post-initialization or initialization of the node, get the memebers and methods from these Strings or StringNames and passes them in the ready-to-connect signals correspondingly. As Strings and StringNames are more easy to be serialized and saved in .tscn, I think this could be a better idea than getting members or methods directly.