[pre.14][solvers] SolverHandler IsHandTracked not working when handedness is set to Everything

[holomatt]

This issue has been migrated a new MRTK repository, and the status of this issue will now be tracked at the following location:

• [pre.14][solvers] SolverHandler IsHandTracked not working when handedness is set to Everything MixedRealityToolkit/MixedRealityToolkit-Unity#192

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Describe the bug

--When SolverHandler is set to Tracked Handedness Left+Right, HandConstraintPalm Up First Hand Detected and Last Hand lost Unity Event fields do not function.
--When there are two SolverHandler with Tracked Handedness set to Left and Right respectively, HandConstraintPalmUp Last Hand Detected field does not consider the opposing hand.

To reproduce

--Add SolverHandler, HandConstraintPalmUp, HandBounds to a GameObject

1. Set a single instance of SolverHandler to Tracked Handedness to Everything (Both does not reproduce the issue)
2. Hook feedback to HandConstraintPalmUp First Handed Detected and Last Hand Detected Fields

OR

1. Add two instances the above component setup and set TrackedHandedness for one to Left and the other to Right
2. Hook feedback to HandConstraintPalm Up First Hand Detected and Last Hand Detected Fields for each solver

Expected behavior

--A single SolverHandler set to Left+Right or Everything should fire events correctly
--Last Hand Detected field on HandConstraintPalmUp should consider the opposing hand

Your setup (please complete the following information)

• Unity Version 2021.3
• MRTK Version 3.pre-14
• MR OpenXR Plugin 1.7.0 (also tried 1.4.4, etc)

Target platform (please complete the following information)

• Editor UWP w/Sim Hand
• HL2

Additional context

In pre.12 this scenario also generated an Assertion Failed:

Microsoft.MixedReality.Toolkit.HandednessExtensions:ToXRNode (Microsoft.MixedReality.Toolkit.Handedness) (at Library/PackageCache/[email protected]/Utilities/Extensions/HandednessExtensions.cs:93)

[holomatt]

cc @Zee2 @RogPodge

[holomatt]

^^Looks like this is where the issue stems from when set to Both. XRI does not appear to work with the current implementation of HandnessExtensions.

[AMollis]

@srinjoym is this something needed for GA?

[AMollis]

@srinjoym I chatted with @holomatt about this. There is an assumption that this issue stems from a limitation in XRI 2.2, and can be addressed by upgrading to XR1 2.3. Can you help determine if there is a solution that doesn't require upgrading to XR1 2.2. The issue for upgrading to XR1 2.3 is #11282

[shaynie]

No repro after upgrading XRI to 2.3. Please re-open if you encounter it again with XRI 2.3 installed.

[holomatt]

Just tested on 3.0.0-pre.15 - this still reproduces. Setting SolverHandler to Both or Everything does not function. Still need to use two instances of the SolverHandler set to Left and Right respectively in order to implement hand menus for both hands.

[AMollis]

@holomatt was still able to reproduce this issue with XRI 2.3.1. I assume this still repros with XRI 2.3.0

Reopening bug.

[holomatt]

After more testing with @AMollis - we found that this issue is an inspector bug specific to selecting the "Everything" value. The "Both" value works great, but once the user changes the Enum away from the default (Both) it latches to "Everything" when selecting more than one hand, resulting in non-operation.

[AMollis]

Hopefully this is fixed now :)