Question Get <T> reference from QueryResults (SynthesizedTrait<T> ?)

I think I'm looking for a way to get a component (ie. Transform, GameObject, Foo, etc) from an object that matches a Proxy's QueryResult.

I'm trying to write an Action that will allow me to move UI under the correct RectTransform without a scene reference. I've seen the Walkthrough Sample, which is good, but seems to require some scene references. AssetBundles and building these at runtime would allow for some more scalable experiences.

So, what I have is

• A Canvas in a scene that has a SynthesizedObject, SynthesizedReferencePoint, SynthesizedPose, and SynthesizedSemanticTag.
• A Proxy in a prefab with a SemanticTagCondition to match the object, and my action component to try and get any information about the Canvas that matches the Semantic Tag.

And... typing this up, I think I see that I need a SynthesizedCanvas, or a SynthesizedRectTransform... I can get the Pose from the SynthesizedPose. Is that how this is supposed to work? Am I looking for a SynthesizedTrait<RectTransform> ?

 

Looks like I can get everything except the associated RectTransform itself, using Synthesized elements, and Traits, an IMatchAcquireHandler. I can pass the position, and the sizeDelta, and other floats, Vector2, etc.

I'm having trouble now getting a custom struct to adhere to the same pattern as the internal Pose class. I think it is because MARS has defined Traits that exist somewhere internal or in an AOT way within the namespace. Is it possible to add new Structs to the FunctionalityProviders?

Getting lots of errors from IProvidesTraits.cs line 47 and line 52

Here's a representation of my code:

Code (CSharp):

1. [Serializable]
2. public struct CustomData : IEquatable<CustomData>
3. {
4.     public Vector2 size;
5.     //... IEquatable stuff
6. }
7.  
8. public class SynthesizedCustomData : SynthesizedTrait<CustomData>, IUsesCameraOffset
9. {
10.     public override string TraitName { get { return "customdata"; } }
11.     public override bool UpdateWithTransform { get { return true; } }
12.     IProvidesCameraOffset IFunctionalitySubscriber<IProvidesCameraOffset>.provider { get; set; }
13.  
14.     public override CustomData GetTraitData()
15.     {
16.         // I actually populate the CustomData, but, psuedo code here
17.         return new CustomData();
18.     }
19. }
20.  
21. public class CustomDataAction : MonoBehaviour, IMatchAcquireHandler, IRequiresTraits
22. {
23.         static readonly TraitRequirement[] k_RequiredTraits = {
24.             new TraitRequirement(new TraitDefinition("customdata", typeof(CustomData)), true)
25.         };
26.  
27.         public void OnMatchAcquire(QueryResult queryResult)
28.         {
29.             if (!queryResult.TryGetTrait("customdata", out CustomData customData))
30.                 return;
31.  
32.             Debug.Log("yay!");
33.         }
34. }

 

Thanks for the help. I'm using MARS 1.3, and Unity 2020.2.7. I've tried a few things, but the simplest way to repro is to copy this code into a script, and add the component to a synthesizedObject, and press play:

Code (CSharp):

1. using Unity.MARS.Data.Synthetic;
2. using Unity.MARS.Providers;
3. using Unity.XRTools.ModuleLoader;
4.  
5. public class CustomData
6. {
7.     int v = 1;
8. }
9.  
10. public class SynthesizedCustomData : SynthesizedTrait<CustomData>, IUsesCameraOffset
11. {
12.     public override string TraitName => "customdata";
13.     public override bool UpdateWithTransform { get { return true; } }
14.  
15.     IProvidesCameraOffset IFunctionalitySubscriber<IProvidesCameraOffset>.provider { get; set; }
16.  
17.     public override CustomData GetTraitData()
18.     {
19.         return new CustomData();
20.     }
21. }

My results complain once when it loads:

And then every frame, it complains again:

 

I've also gone pretty far down SynthesizedTrackable, IProviderTraits (and how they are registered with MARSDatabase), as well as IUsesMARSTrackableData, and SimulatedProviders. I've tried developing this functionality within a Packages Directory, as well as in Assets. It seems that the Generated.cs file containing the partial MARSDatabase defines the types that are supported. I appreciate that these are no longer Internal, however I'm not seeing an easy extensible way to add our own Trackables or Traits. And Debugging through the interfaces is fairly tedious.

Near as I can tell, the AddTrait<T> or AddOrUpdateTrait<T> methods (defined in the IProvidesTraitsMethods class) have an internal getter that isn't retrieving my classes SynthesizedTrait<T> values. Not quite clear why.

 

I've tried the suggested:

The files that got regenerated were the same (Only diff was new meta guids), and the errors I saw were the same as well. Didn't pick-up or include my CustomData class from the example above.

 

Bug Filed (Case# 1333546): https://fogbugz.unity3d.com/default.asp?1333546_20ccdvk59fvhp45k

Or this can be duplicated by copying this simple script (SynthesizedCustomData.cs):

Code (CSharp):

1. using Unity.MARS.Data.Synthetic;
2. using Unity.MARS.Providers;
3. using Unity.XRTools.ModuleLoader;
4. public class CustomData
5. {
6.     int v = 1;
7. }
8. public class SynthesizedCustomData : SynthesizedTrait<CustomData>, IUsesCameraOffset
9. {
10.     public override string TraitName => "customdata";
11.     public override bool UpdateWithTransform { get { return true; } }
12.     IProvidesCameraOffset IFunctionalitySubscriber<IProvidesCameraOffset>.provider { get; set; }
13.     public override CustomData GetTraitData()
14.     {
15.         return new CustomData();
16.     }
17. }

And adding SynthesizedObject component, and the above component (SynthesizedCustomData) to a gameObject in a MARS scene. Then press play.

Unity 2020.1.9f1, Unity MARS 1.3.0, Import Samples, Open a MARS sample scene, add the script.