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Unrealistic Angles in Inverse Kinematics (FABRIK)

Development Discussion C++ Gameplay Programming
#1

In my setup, I am using the FABRIK node in the Animation Graph, to animate my character’s arms and legs towards 4 target transforms. These are set in C++, and shared with the Event Graph where they’re passed on into the Animation Graph. However, I am lacking a way to specify angular constraints on my joints, to avoid unhuman poses like this:

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So the only constraints I was able to find where in the PhysicsAsset, but this is not something that would be used for IK.
There has to be a clean way of doing this, but I couldn’t even find documentation on this problem anywhere.
Any help would be greatly appreciated.

#2

I am having the same issues. Not sure why. This should be moved to the animation forum I think.

#3

I have reposted this problem to Animations.

#4

An update to the FABRIK joint limits:

I found the dev who contributed the FABRIK implementation on reddit and contacted him. He/she
confirmed that there are no joint limits implemented for the FABRIK node, even though the
theoretical algorithm describes a way of doing so.

Consequently, anyone using the FABRIK node will have to implement joint limits or constraints
him/herself. The paper on this algorithm can be found here: