Remove shapes, they will be leaked on exit

Asolix

I would have assumed that a simple Free or QueueFree on a PhysicsBody3D would delete all added shapes and their owners, children and other things related to them.
Even with following code I still get leaked things:

public override void _Ready()
{
    var _physicsBody3D = new StaticBody3D();
    var shape = new BoxShape3D();
    var colShape = new CollisionShape3D()
    {
        Name = "collision_shape",
        Shape = shape
    };

    var owner = new GodotObject();
    uint ownerId = _physicsBody3D.CreateShapeOwner(owner);
    _physicsBody3D.ShapeOwnerAddShape(ownerId, colShape.Shape);

    Exit();
}

private void Exit()
{
    SceneTree tree = GetTree();

    RemoveAllShapes();
    _physicsBody3D?.Free();

    tree.ToSignal(
        tree, SceneTree.SignalName.ProcessFrame
    ).OnCompleted(
        () => tree.Quit()
    );
}

private void RemoveAllShapes()
{
    if (_physicsBody3D != null)
    {
        foreach (uint shapeOwner in _physicsBody3D.GetShapeOwners().Select(v => (uint)v))
        {
            var owner = _physicsBody3D.ShapeOwnerGetOwner(shapeOwner);
            _physicsBody3D.ShapeOwnerClearShapes(shapeOwner);
            _physicsBody3D.RemoveShapeOwner(shapeOwner);
            owner.Free();
        }
    }
}

What do I need to do to ensure that the shapes are properly deleted?

I get the following error with the above code after the program was automatically terminated in the next frame:

ERROR: 1 RID allocations of type 'P11GodotBody3D' were leaked at exit. 
ERROR: 1 RID allocations of type 'P12GodotShape3D' were leaked at exit.
WARNING: ObjectDB instances leaked at exit (run with --verbose for details).
     at: cleanup (core/object/object.cpp:2047)

Godot Version: v4.1.1.stable.mono.official [bd6af8e0e]

Thanks

SnapCracklins

Asolix i only see ‘free’ in there and not ‘queue_free’. Free releases nodes but it’s not always safe to do so. ‘Queue_free’ releases then when it is safe to do so. I’d start there.

The other problem is that you are flushing physics pieces outside of ‘physics_process’ which godot tends to not like. I would run that RemoveAllShapes function in there but try queue_free first though.

Also - I am not sure how you project is set up, but it might be easier to just instance the Shape Owner you need with all the part as its own scene rather than code everything building it, because somewhere something is not syncing up.

Asolix

Ok, I have to admit that a very stupid error crept into the example code above: the private variable _physicsBody3D, which unfortunately was not listed in the code, is initialized again in the _Ready method. Anyway, let's not talk about it any further. 😉

However, even if I use QueueFree and destroy the shapes beforehand in the physics process, a leak remains:

ERROR: 1 RID allocations of type 'P12GodotShape3D' were leaked at exit.

Unfortunately, creation and removal must be done in code.

SnapCracklins

Asolix interesting. I’ve had to do manual changing like this sometimes too with physics. Doesn’t happen much in 3.5 but I have seen it. Maybe try a variable - like call it “flushed” - and keep it false until you need it. Flip it in physics process until when “flushed” is true, then dump the physics and flip “flushed” back?

Asolix

I have now done some tests.
If you create a PhysicsBody3D and assign a CollisionShape3D to it and also add a Shape3D to it, you have to remove the PhysicsBody3D with QueueFree and also the CollisionShape3D object.
Shape3D is a resource and will be removed automatically.
But you have no possibility to get the CollisionShape3D object from the PhysicsBody3D body. Also not from the derived objects like RigidBody3D, StaticBody3D, ...
So you need to reference the CollisionShape3D object in a variable or store it in PhysicsBody3D to be able to remove both objects later.
The shapes or the ShapeOwner(s) in the loop from my post can be removed beforehand to avoid a leak of the ShapeOwner. However, if you wait one frame after removing the CollisionShape3D, it will automatically be released.

It would be nice to have a way to get a reference from the body to the already assigned CollisionShape3D.
Maybe I'm missing something, but I couldn't find a way to get to the CollisionShape3D object.

synthnostate

Asolix When you create a collisionshape in the editor it's a child of the physicsbody. Why don't you just do that in code?

physicsbody.add_child(colshape)
colshape.owner = physicsbody

Then you can retrieve it with physicsbody.find_children("", "CollisionShape3D", false) or physicsbody.get_child(0) if you know it's always the only child.

Maybe Godot will automatically free it if it's a child node.

DaveTheCoder

This is a bug, isn't it? It should be submitted.

Asolix

Of course, I tried it that way. But what I have never done is to set the Node.Owner. If this is set, the corresponding ShapeOwner is removed as well. Thanks for the hint.

xyz

Asolix Owner property is irrelevant. Here's how things work.

Everything that inherits from RefCounted is garbage collected via reference counting, so you don't need to care about its cleanup at all. This includes all Resource types since Resource inherits RefCounted

Nodes do not inherit RefCounted and must be manually freed. When you call Free() or QueueFree() on a node, all of its children will be freed as well.

So if your nodes and shapes are properly set up, that is, all collision shape nodes are children of the body and all shape resources are only referenced from collision shape nodes, then all you need to do is call *Free() on the body node and everything else will be properly cleaned up.

Note that doing this from _Ready() might not be the best idea.

synthnostate

Yeah, owner is mainly used in editor tools, but it's worth trying in a situation like this. Wouldn't be the first time the docs were wrong or missing crucial information.

Asolix

Ok, thanks for the detailed explanation. I think I get it now. I now have all the shape things as child nodes and it works fine.
Thanks to all