Add a way to disable any node

[me2beats]

Problems:

1. When I create scenes I often experiment with nodes properties values (position, size etc).
   So sometimes I just duplicate the node, set the old node visibility to false and then change some parameters for the new node.
   Then I compare results, and delete the old node if the new one looks/works better.
   But there are many cases when I can't easily use this approach, for example if there is a reference to the node by name like onready var node =$path_to_the_node, or if the node uses signals.
   I want the node to still be in the tree in the editor, but completely disabled, which means it will not exist in the game at all.

2. Sometimes I just want to quickly test how the game would behave if I remove some node from the editor.
   I solve it deleting the node then run the game then when I close the game window I press Ctrl+z to undo the node deletion, but this is not handy.

Solution:

The idea is to have an option, for example a checkbox (in the node right-click context menu), pressing it the node would still be in the Scene Tree Editor, but completely disabled like it doesn't exists as a node, (including the tool mode I guess?).
That means $Node won't work and get_children() will not have disabled nodes in the children list.

• Name collisions in the disabled nodes should be allowed: the user can have multiple disabled nodes with name Node and at the same time one enabled node with name Node.
• There should be an easy way to clearly see in the editor that a node is disabled.
• All changed properties of disabled node are still stored in the scene, the node simply not created in the game, even Node.new() is not called.
• I don't think it should be as a property, I don't see useful cases, this should be kinda editor/Packed Scene feature only
• See also set node as a Placeholder, this is kinda similar, but it works only for scenes and Placeholder's goal is different (delayed creation of the nodes)

[Calinou]

The use case seems a bit contrived to me. I don't see why you'd need to do this after the process mode refactor has landed in 4.0.alpha.

[me2beats]

• the node still exists in the game and in the editor
• the node can be accessed from the code of other nodes
• _init(), enter_tree() and _ready() are called
• unable to create a node named Node, if I already have a node with disabled proccess named Node (I think it could be allowed for disabled nodes)
• signals are still emitted

[me2beats]

the idea is to not create the node in the game at all

[wareya]

As a workaround, could you add code to instantly destroy undesired nodes in _init()? (have not tested if this would actually work)

But there are many cases when I can't easily use this approach, for example if there is a reference to the node by name like onready var node =$path_to_the_node

If the node doesn't exist in the game at all, then this will break regardless. The only way for this to not break is if the node does exist, but spawns in a 'paused' state of some kind.

[me2beats]

sometimes the idea is to let it break, when testing. In the release version the code should be fixed of course