NavigationServer2D agents confused with their 3D counterpart?

[Dan-The-Assassin]

Tested versions

• Reproducible in: v4.3.stable.mono.official [77dcf97]

System information

Godot v4.3.stable.mono - Windows 10.0.19045 - Vulkan (Forward+) - dedicated NVIDIA GeForce RTX 3060 (NVIDIA; 32.0.15.6094) - 13th Gen Intel(R) Core(TM) i9-13900KF (32 Threads)

Issue description

I've attempted coding an avoidance agent through script, but the result is not the expected one. The NavigationServer2D agent produces the incorrect safe velocity, a Vector3 instead of a Vector2, where the y value is always 0 and the avoidance does not work at all.

Steps to reproduce

Create a CharacterBody2D. Then, create an agent in script through the NavigationServer2D functions, give it a callback for the safe velocity. In the physics process, give the agent a velocity. In the callback for safe velocity, give the CharacterBody2D the safe velocity. You'll notice the y will always be 0. If the vector is instead made a Vector3, you'll notice the z has a value. Giving the velocity's y the safe velocity's z value seems to make movement work as intended, except for the avoidance which simply doesn't work.

Minimal reproduction project (MRP)

testproject.zip

[AThousandShips]

This is not a bug, it's because the underlying server is the 3D server (until 4.5), and in 4.5 it is still a Vector3 for compatibility, we have discussed changing it however, but it is not a bug, it should probably be documented more clearly for 4.4 and earlier though regardless if we break compatibility in 4.5

This is partially documented here

[smix8]

For Godot 4.5 with the split to the dedicated NavigationServer2D we should imo use that event to break compatibility and change it from Vector3 to Vector2.

For Godot 4.3 or 4.4 it is too late to change that. What we could do is update / extend the agent script example found here (above the agent scripts) to make it more clear that a Vector3 callback parameter is expected in those versions.

[Dan-The-Assassin]

This is not a bug, it's because the underlying server is the 3D server (until 4.5), and in 4.5 it is still a Vector3 for compatibility, we have discussed changing it however, but it is not a bug, it should probably be documented more clearly for 4.4 and earlier though regardless if we break compatibility in 4.5

This is partially documented here

Is it not a bug that the agent does not do avoidance though?

[AThousandShips]

The vector is converted as detailed in the documentation I linked, it should be Vector3(vel.x, 0.0, vel.y), not using the y

[Dan-The-Assassin]

Using it as such, for example with a code like the following, the character bodies 2D move, yes, but there is no avoidance.

    {
        Velocity = new Vector2(safeVelocity.X, safeVelocity.Z);
        MoveAndSlide();
    }

[smix8]

Is it not a bug that the agent does not do avoidance though?

This might be an issue with a node or script conflict e.g. shadowing some properties or functions on the node class, or even some C# specific issue.

This basic gdscript used on a generic Node2D works just fine (tested in Godot 4.4.1):

extends Node2D

var agent: RID

func _ready() -> void:
	agent = NavigationServer2D.agent_create()
	NavigationServer2D.agent_set_map(agent, get_world_2d().navigation_map)
	NavigationServer2D.agent_set_avoidance_enabled(agent, true)
	NavigationServer2D.agent_set_avoidance_callback(agent, Callable(self, "_avoidance_done"))

func _physics_process(delta: float) -> void:
	NavigationServer2D.agent_set_position(agent, global_position)
	NavigationServer2D.agent_set_velocity(agent, Vector2(10.0, 15.0))

func _avoidance_done(safe_velocity):
	print("safe_velocity: %s" % safe_velocity)

[AThousandShips]

Please provide an MRP to make this easier to test and fix:

• A small Godot project which reproduces the issue, with no unnecessary files included. Be sure to not include the .godot folder in the archive (but keep project.godot).
• Having an MRP is very important for contributors to be able to reproduce the bug in the same way that you are experiencing it. When testing a potential fix for the issue, contributors will use the MRP to validate that the fix is working as intended.
• Drag and drop a ZIP archive to upload it (max 10 MB). Do not select another field until the project is done uploading.
• Note for C# users: If your issue is not C#-specific, please upload a minimal reproduction project written in GDScript. This will make it easier for contributors to reproduce the issue locally as not everyone has a .NET setup available.

[Dan-The-Assassin]

testproject.zip

[Dan-The-Assassin]

From my understanding, if they are given an avoidance radius and the avoidance is enabled, the safe velocity is supposed to be such as that they keep that distance from each other, but they don't. My apologies if this is a mistake on my side