Physics.ClosestPoint error with ARPlane and ARMesh in Unity using Ultraleap Plugin 7.1.0

[tichise]

Description

I am using the Ultraleap Plugin 7.1.0 in Unity with the LeapServiceProvider in DesktopMode. I have added Physical Hands Manager to my scene, and I am generating AR planes and meshes using ARFoundation. However, when attempting to interact with non-convex objects (such as ARPlane or ARMesh), I encounter the following error:

Physics.ClosestPoint can only be used with a BoxCollider, SphereCollider, CapsuleCollider and a convex MeshCollider.
UnityEngine.Collider:ClosestPoint (UnityEngine.Vector3)
Leap.PhysicalHands.ContactBone:UpdateObjectDistances (UnityEngine.Collider[],int) (at 

I tried adding the IgnorePhysicalHands component to ARPlane and ARMesh, but this did not resolve the issue. Additionally, I attempted to disable collision using layers, but this approach was also unsuccessful. Since ARPlanes and ARMeshes are dynamically generated and non-convex by nature, it is difficult to make them convex. This is because making them convex would affect other processes. This issue also has a significant impact on other behaviors in the scene.

It seems that the Physics.ClosestPoint method is being called on non-convex colliders, which is unsupported. Is there a recommended workaround for handling AR-generated planes and meshes when interacting with Physical Hands Manager?

Steps to Reproduce

1. Add Physical Hands Manager to a Unity scene.
2. Use ARFoundation to generate AR planes or AR meshes.
3. Attempt interaction with non-convex AR objects using Physical Hands Manager.
4. Observe the error in the console.

Expected Behavior

Physical Hands Manager should be able to interact with AR planes and meshes without causing the Physics.ClosestPoint error.

Actual Behavior

The error occurs when interacting with non-convex colliders, such as AR-generated planes or meshes, which aren't supported by the Physics.ClosestPoint method.

Environment

• Unity version: [Specify your Unity version]
• ARFoundation version: [Specify your ARFoundation version]
• Ultraleap Plugin version: 7.1.0
• LeapServiceProvider mode: DesktopMode

[rorygames]

Hey, this is unfortunately a Unity physics limitation and not something that can be fixed. Unity's physics system cannot handle non-convex meshes reliably (specifically when using non-kinematic rigidbodies), they essentially have no volume and the physics system can't calculate them.

My suggestion would be to do one of a few things:

• Simply toggle the convex checkbox (which as you said will cause other issues with other systems)
• Create a helper script that generates a secondary object that has another mesh collider that is convex, without adjusting the original one. You would use the secondary object for your interaction and simply have the ARmesh object follow it (someone on the Unity forums ran into a similar problem before ) This would also be more performant and would reduce the impact on your application.

Please note that I do not have any prior experience with AR foundation's workings, so cannot provide any support with it.