Can't use paths to reference SubViewport nodes

[blackears]

Godot version

v4.0.2.stable.official [7a0977c]

System information

Windows 10, Compatability

Issue description

I'm trying to create a Control that will automatically render a thumbnail of a material. To do this, I've created a TextureRectangle to display the thumbnail and a SubViewport to create a simple 3D scene to render the thumbnail. Unfortunately this is causing a lot of problems with Godot being unable to resolve the path to the viewport. I read a few other bug reports I think are related, but the node that is using the SubViewport is a peer of the viewport itself.

#55818

Steps to reproduce

Try to run this project. You will get these errors when Godot tries to resolve the path.

E 0:00:01:0049 get_node: Node not found: "SubViewport" (relative to "Control").
<C++ Error> Method/function failed. Returning: nullptr
<C++ Source> scene/main/node.cpp:1364 @ get_node()
E 0:00:01:0049 setup_local_to_scene: ViewportTexture: Path to node is invalid.
<C++ Error> Condition "!vpn" is true.
<C++ Source> scene/main/viewport.cpp:76 @ setup_local_to_scene()

Minimal reproduction project

subviewportTrumbnailTest.zip

[KoBeWi]

The problem is that the ViewportTexture initializes too early, before the node hierarchy is ready.

[dandeliondino]

Thank you for this fix. I had the same error (and a few related ones). When I removed the assignment from the inspector and instead assigned the ViewportTexture in the parent's ready function, the errors disappeared.

Also, I would love to see the is_ready() function in the PR merged. Despite having is_inside_tree(), I still end up creating my own check for ready a few times per project, and it would be great to have it built-in.