2 separate operations on a Config Joint / Rigidbody within a single FixedUpdate

Unity Engine
1

Problem - It seems these two ‘operations’ cannot be performed in succession. All I get is the second part (AddTorque). My guess is Unity combines the entire thing and runs it together at the end of the FixedUpdate. Can I overcome this somehow or is that just how it works?

 private void FixedUpdate()
    {
        JointDrive jd1 = new JointDrive
        {
            positionSpring = Mathf.Infinity,
            maximumForce = Mathf.Infinity,
            positionDamper = 50f
        };
        bike_CJ.slerpDrive = jd1;

        bike_CJ.xMotion = ConfigurableJointMotion.Locked;
        bike_CJ.yMotion = ConfigurableJointMotion.Locked;
        bike_CJ.zMotion = ConfigurableJointMotion.Locked;
        bike_CJ.targetRotation = Quaternion.AngleAxis(30 * lean, bike_TR.forward); // lock the joint, rotate it with target rotation force

        JointDrive jd2 = new JointDrive
        {
            positionSpring = 0f,
            maximumForce = 0f,
            positionDamper = 0f
        };
        bike_CJ.slerpDrive = jd2;

        bike_CJ.xMotion = ConfigurableJointMotion.Free;
        bike_CJ.yMotion = ConfigurableJointMotion.Free;
        bike_CJ.zMotion = ConfigurableJointMotion.Free;
        bike_RB.AddTorque(Vector3.up * 10, ForceMode.Impulse); // disable target rotation force, unlock the joint, rotate it with AddTorque
    }
2

That’s how it works. Note that your code is not performing any operation in the joint: it’s just configuring the public properties exposed by the joint component. At the end of FixedUpdate the physics engine takes the values that are in the properties and performs the physic operations with them. So physics only “sees” the latest values you left there.

3

Yeah I figured as much and was thinking about things all wrong. Cheers.