Simulating a Fidget Spinner

Questions & Answers
1

Hi,
I just started some code that is supposed to simulate a real world fidget spinner. After scribbling the system on paper i thought i had a good solution, and it works fine for some angles except around certain angles where it starts to show some weird behaviour sort of changing direction. I can’t figure out what’s causing this. Pasting code below.

    if (Input.GetMouseButton(0))
    {
        Debug.Log(transform.rotation.z.ToString());
        Vector3 v_deltaInput = lastInput - Input.mousePosition;
        Vector3 v_unitTheta = -Mathf.Sin(transform.rotation.z) * Vector3.right + Mathf.Cos(transform.rotation.z) * Vector3.up;
       f_projection = Vector3.Dot(v_unitTheta, v_deltaInput);
        transform.Rotate(Vector3.fwd, f_projection);
        lastInput = Input.mousePosition;
    }
    else {
        transform.Rotate(Vector3.fwd, f_projection);
    }
}
2

Solved. Perhaps abit hard-coded, but it works in my specific casae. I’ll post my solution here incase anyone else runs in to a similiar problem. Basically u pop it on a 2d sprite and spin.

       if (Input.GetMouseButtonDown(0))
        {
            f_projection = 0.0f;
        }
        if (Input.GetMouseButton(0))
        {
            Vector3 v_deltaInput = lastInput - Input.mousePosition;
            Vector3 v_unitX = new Vector3(1, 0, 0);
            Vector3 v_unitY = new Vector3(0, 1, 0);
            f_projectionX = Vector3.Dot(v_unitX, v_deltaInput);
            f_projectionY = Vector3.Dot(v_unitY, v_deltaInput);
            if (Input.mousePosition.y < Screen.height / 2)
            {
                f_projectionX = -f_projectionX;
            }
            if (Input.mousePosition.x > Screen.width / 2)
            {
                f_projectionY = -f_projectionY;
            }
            f_rot = f_projectionX + f_projectionY;
            transform.Rotate(Vector3.forward, f_rot);
            lastInput = Input.mousePosition;
        }
        else
        {
            transform.Rotate(Vector3.forward, f_rot);
        }