Area3D does not see newly instanced StaticBody3D with Monitoring/Monitorable enabled

[cridenour]

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Bugsquad note: This issue has been confirmed several times already. No need to confirm it further.

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Godot version

4.0.beta1

System information

Windows 10

Issue description

I'm aware of #17238 (specific to Monitorable being enabled, which doesn't help here) and #57539 which is specific to moving a StaticBody. Could be the same fix works for this and #57539 but I did not want to miss this use-case.

When you have a Area3D and a new StaticBody3D is placed in the scene, it will not detect it until you change the collision_layer or collision_mask. I imagine other "touches" will force an update as well.

Steps to reproduce

1. Create a scene with an Area3D.
2. After scene is ready, add a StaticBody3D with the layer of the Area3D's mask.

Optional workaround:
3. After more time, update the collision_layer or collision_mask.

Minimal reproduction project

Area3D StaticBody.zip

This MRP automates showing the bug and the current workaround.

[Brandtweary]

I'm having this exact same bug in 2D. I'm using Godot version 4.0.beta4, on Windows 11.

[jsardev]

Same issue with Area2D and StaticBody2D, Godot 4.0.2.stable, MacOS.

[RawEnchilada]

Area2D doesn't emit mouse_entered event as well if instantiated from script.
Linux v4.0.3.stable.mono.official

[Razboinicul]

Same issue with v4.1.1.stable.official [bd6af8e], Linux

[Denatle]

Same with Area2d, 4.2.stable, windows 11

[QSSE2016]

Hey everyone, also running into this issue in Godot 4.3 stable. Found a rather strange solution to it.
i was setting collisions through script (via collision_layer = ...).

Before (not working):
`func _ready() -> void:

$".".collision_layer = 3 + int(element)`

After (working)
`func _ready() -> void:

var body: StaticBody2D = $"."

body.set_collision_layer_value(3 + int(element),true)`

I have no idea why it wasnt working before. Is Layer 1 really important to the engine or something? cause with the After code you still keep that layer 1 default true value. Not really sure, but hope this helps.

[LO-0116]

bug persists in v4.3.stable.official [77dcf97], windows 11.

Perhaps note-worthy: collision between instantiate StaticBody2Ds are broken, but not broken between Area2Ds