Rod bending by blend tree in Unity

Question

I'm working on implementing rod bending by blend tree. Once, I've made a system to achieve that but then after I found out it doesn't work correctly in every angles and situations. I fills directionX (First parameter of blend tree) and directionY (Second parameter of blend tree) by using this code:

            Vector3 projectedLineXY = Vector3.ProjectOnPlane(_baitHandler.transform.position - _context.rodTip.position, _context.rod.transform.forward);
            float angleSignXY = Mathf.Sign(Vector3.Dot(Vector3.Cross(_context.rod.transform.up, projectedLineXY), _context.rod.transform.forward));
            float angleXY = Vector3.Angle(_context.rod.transform.up, projectedLineXY) * angleSignXY;
            Vector3 projectedLineZY = Vector3.ProjectOnPlane(_baitHandler.transform.position - _context.rodTip.position, _context.rod.transform.right);
            float angleSignZY = Mathf.Sign(Vector3.Dot(Vector3.Cross(_context.rod.transform.up, projectedLineZY), -_context.rod.transform.right));
            float angleZY = Vector3.Angle(_context.rod.transform.up, projectedLineZY) * angleSignZY;

_baitHandler.transform.position is bait position and _context.rodTip.position is tip of rod position. _context.rod is rod gameObject and other things related to that are its directions.

Please if you know how I can achieve the correct solution for that, explain what exactly I can fill these 2 parameters of blend tree.

Video from blend tree

Answer 1

I hope it is helpful for anyone who is looking for implementing rod bending by blend tree. Finally I got to this after so many iterations:

private const float ROD_BEND_CORRECTION_ERROR = 0.01f;
private readonly int DIRECTION_X_HASH = Animator.StringToHash("directionX");
private readonly int DIRECTION_Y_HASH = Animator.StringToHash("directionY");

public void UpdateRodBend(float deltaTime, float strength = 1f)
{
    for (int i = 0; i < 10; i++)
    {
        Vector3 line = bait.position - rodTip.position;
        Vector3 projectedY = Vector3.ProjectOnPlane(line, rodTip.forward);
        float angleSignY = Mathf.Sign(Vector3.Dot(Vector3.Cross(rodTip.up, projectedY), rodTip.forward));
        float angleY = Vector3.Angle(-rodTip.up, projectedY) * angleSignY;
        if (Mathf.Abs(angleY / 90) > ROD_BEND_CORRECTION_ERROR)
        {
            animator.SetDirectionY((angleY / 90) * deltaTime * rodBendingSmoothSpeed, strength);
            animator.ForceUpdateRodAnimator();
        }
        line = bait.position - rodTip.position;
        Vector3 projectedX = Vector3.ProjectOnPlane(line, rodTip.right);
        float angleSignX = Mathf.Sign(Vector3.Dot(Vector3.Cross(_context.rodTip.up, projectedX), -rodTip.right));
        float angleX = Vector3.Angle(-rodTip.up, projectedX) * angleSignX;
        if (Mathf.Abs(angleX / 90) > ROD_BEND_CORRECTION_ERROR)
        {
            animator.SetDirectionX((angleX / 90) * deltaTime * rodBendingSmoothSpeed, strength);
            animator.ForceUpdateRodAnimator();
        }
    }
}

public void SetDirectionX(float value, float maxLength)
{
    Vector2 clamped = Vector2.ClampMagnitude(new Vector2(animator.GetFloat(DIRECTION_X_HASH) + value, animator.GetFloat(DIRECTION_Y_HASH)), maxLength);
    animator.SetFloat(DIRECTION_X_HASH, clamped.x);
}

public void SetDirectionY(float value, float maxLength)
{
    Vector2 clamped = Vector2.ClampMagnitude(new Vector2(animator.GetFloat(DIRECTION_X_HASH), animator.GetFloat(DIRECTION_Y_HASH) + value), maxLength);
    animator.SetFloat(DIRECTION_Y_HASH, clamped.y);
}