AnchorableBehaviour weirdness?

[JCorvinus]

So I've replaced our internal anchor scripts with the ones from the interaction engine, and I'm noticing something strange.

In GetNearestValidAnchor(), there is the following:

      foreach (var testAnchor in anchorsToCheck) {
        if ((requireAnchorHasSpace && (!anchor.allowMultipleObjects || anchor.anchoredObjects.Count == 0))
            || (requireAnchorActiveAndEnabled && !anchor.isActiveAndEnabled)) continue;

Is that reference to anchor supposed to be a reference to testAnchor? It seems like the current anchor's ability to hold multiple multiple objects and its active state are irrelevant to whether or not testAnchor is a valid choice.

[nbenson]

You're totally right! Thanks for the catch.

Not only should that be testAnchor and not anchor, but also those inline booleans make this code very unreadable. I made the testAnchor switch and rewrote it for better readability (and might have caught an additional logic error in the process) in this PR:

Make anchor requirements readable, fix logic bug

We've got some larger issues to tackle before we release the next Interaction Engine update, so I'd suggest taking a look at the PR diff and modifying your local code if you need it fixed ASAP.

If any other developers are relying on this functionality as well, we can make a hotfix, so other devs, please respond to this thread (or make more threads) if it should be a priority.

[JCorvinus]

I found another one. The AnchorableBehaviour has an (awesome) feature that lets it attract to nearby hands. If you're using controllers-only (meaning no optical hand tracking), it'll null ref on hitting updateAttractionToHand().

Since some areas of the code are explicit about whether or not hands or controllers are acceptable, this might not technically be a bug (well the null ref is definitely a bug but you know what I mean), but either way in our project I wanted the controllers to attract anchorable things just like hands do, so I changed the code to the following:

        private void updateAttractionToHand()
        {
            if (interactionBehaviour == null || !isAttractedByHand || interactionBehaviour.hoveringControllers.Count == 0)
            {
                if (_offsetTowardsHand != Vector3.zero)
                {
                    _offsetTowardsHand = Vector3.Lerp(_offsetTowardsHand, Vector3.zero, 5F * Time.deltaTime);
                }
                return;
        }

        float reachTargetAmount = 0F;
        Vector3 towardsHand = Vector3.zero;
        if (interactionBehaviour != null)
        {
            if (isAttractedByHand)
            {
                if (interactionBehaviour.isHovered)
                {
                    InteractionController hoveringController = interactionBehaviour.closestHoveringController;
                    Vector3 target = hoveringController.hoverPoint;

                    reachTargetAmount = Mathf.Clamp01(attractionReachByDistance.Evaluate(
                                          Vector3.Distance(target, anchor.transform.position)
                                        ));
                    towardsHand = target - anchor.transform.position;
                }

                Vector3 targetOffsetTowardsHand = towardsHand * maxAttractionReach * reachTargetAmount;

                _offsetTowardsHand = Vector3.Lerp(_offsetTowardsHand, targetOffsetTowardsHand, 5 * Time.deltaTime);
            }
        }
    }

[nbenson]

Yeah, AnchorableBehaviour was created before the InteractionController abstraction came around, so I think this is just something we missed in the transition.

I've got an issue up for this as well:

Issue: Support attracting AnchorableBehaviours to nearby controllers as well as hands