Is there a RotateAround functionality for Rigidbody 2D's?

Question

Hello,

I've been trying to make a top-down 2d game which involves the weapon swinging around the player based on the momentum of the mouse x input, I was previously transforming the weapon to pivot around the player based on the RotateAround function but it wasn't reacting to incoming projectile physics. I have since switched transforming to rigidbody.MoveRotation() but I cannot work out how to rotate around a specific pivot when using this form of rotation.

Here is the code in question, currently it does not rotate around the player but does rotate in place with mouse x input:

 using UnityEngine;
 using System.Collections;
  
 public class OrbitPlayer : MonoBehaviour {
  
     public Transform target;
     private Rigidbody2D myRigidbody;
     public float orbitDistance = 10.0f;
     private Vector3 relativeDistance = Vector3.zero;
     private float mouseXspeed;
     private Vector3 targetPosition;
 
     // Use this for initialization
     void Start () {
         if(target != null) 
         {
             relativeDistance = (transform.position - target.position).normalized * orbitDistance;
         }
         myRigidbody = GetComponent<Rigidbody2D>();
     }
 
     void Orbit(float mouseXspeed, Vector3 targetPosition)
     {
         if(target != null)
         {
             Debug.Log(targetPosition);
             // Moves with the target
             myRigidbody.MovePosition(targetPosition);
             // Rotates based on Mouse X input
             myRigidbody.MoveRotation(mouseXspeed);
         }
     }
     
     void Update () {
         
         targetPosition = target.position + relativeDistance;
 
         // Gets the movement of the mouse in the x axis
         float mouseXaxis = Input.GetAxis("Mouse X");
         // Keeps knowledge of the axis and adds accordingly to movement
         mouseXspeed += mouseXaxis;
     
     }
     
     void FixedUpdate() {
         Orbit(mouseXspeed, targetPosition);
     }
 }

Is there a way to use RotateAround for a rigidbody or is there an equivalent?

Answer 1

I've instead managed to use the parametric equation to work out x and y coordinates to make the weapon move to specific points in a circle around the player with the radius of 1.

 using UnityEngine;
 using System.Collections;
  
 public class OrbitPlayer : MonoBehaviour {
  
     public Transform target;
     private Rigidbody2D myRigidbody;
     private Vector3 relativeDistance = Vector3.zero;
     private float mouseXspeed;
     private float mouseXaxis;
     private Vector3 targetPosition;
     private Vector3 weaponPos;
 
     // Use this for initialization
     void Start () {
         myRigidbody = GetComponent<Rigidbody2D>();
         mouseXspeed = 0;
     }
  
     void Orbit(float mouseXspeed, Vector3 weaponPos)
     {
         if(target != null)
         {
             targetPosition = target.position;
             // Moves with the target
             myRigidbody.MovePosition(targetPosition + weaponPos);
             // Rotates based on Mouse X input
             myRigidbody.MoveRotation(mouseXspeed);
             
         }
     }
 
     void Update () {
         
         // Gets the movement of the mouse in the x axis
         mouseXaxis = Input.GetAxis("Mouse X");
         // Keeps knowledge of the axis and adds accordingly to movement
         
         mouseXspeed += mouseXaxis;
 
         weaponPos.x = Mathf.Cos(mouseXspeed);
         weaponPos.y = Mathf.Sin(mouseXspeed);
         weaponPos.z = 0;
 
         Debug.Log("mouse X Speed: " + mouseXspeed);
 
         print("mouseXspeed: "+ mouseXspeed+ " weaponPos: " + weaponPos);
     
     }
      
     void FixedUpdate() {
         Orbit(mouseXspeed*(180/Mathf.PI), weaponPos);
     }
 }

This does initialize the weapon position to be at rotation 0 with the coordinates directly 1 unit right of the target (player) as cos(0)=1

Is there a RotateAround functionality for Rigidbody 2D's?

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