2D Physics Moving an Object with the Mouse

Hi, right now I am trying to make a script that moves an object with the mouse, specifically a paddle. The script I have keeps the object on a specific y value, while matching the x value of the mouse.

Code (CSharp):

1.  
2. {
3.  
4.    [SerializeField] private float screenWidthInUnits = 18f;
5.  
6.      // Use this for initialization
7.    void Start () {
8.      
9.    }
10.    
11.    // Update is called once per frame
12.    void Update ()
13.    {
14.       float mousePosInUnits = Input.mousePosition.x / Screen.width * screenWidthInUnits;
15.       Vector2 paddlePos = new Vector2(mousePosInUnits   , transform.position.y);
16.       transform.position = paddlePos;
17.    }
18.      
19.    
20.    
21. }
22.  

However the problem arises when I move the mouse too fast to hit the ball, it passes directly over top of the ball and causes the ball's velocity to become zero. I believe that the problem is that the paddle has no velocity and it is just moving to a direct position.

How would I make a script that would allow the paddle to follow the mouse, without too much delay, but also with enough friction that it would not go over an object immediately?

Thanks.

 

Hey thanks, this is indeed what I was looking for, also you have a new subscriber

This is the script that I attached to my paddle.

Code (CSharp):

1.  
2. public class EternalFolloScripy : MonoBehaviour
3. {
4.     public TargetJoint2D TJ2D;
5.  
6.     public bool m_DrawDragLine = true;
7.     public Color m_Color = Color.cyan;
8.     // Start is called before the first frame update
9.     void Start()
10.     {
11.         TJ2D = GetComponent<TargetJoint2D>();
12.     }
13.  
14.     // Update is called once per frame
15.     void Update()
16.     {
17.         var worldPos = Camera.main.ScreenToWorldPoint (Input.mousePosition);
18.        
19.         TJ2D.target = TJ2D.transform.InverseTransformPoint(worldPos);
20.        
21.        
22.         if (TJ2D)
23.         {
24.             TJ2D.target = (worldPos);
25.  
26.          
27.             if (m_DrawDragLine)
28.                 Debug.DrawLine (TJ2D.transform.TransformPoint (TJ2D.anchor), worldPos, m_Color);
29.         }
30.  
31.  
32.     }
33. }
34.  
35.  

However when I try to disable movement on the y axis:

Code (CSharp):

1.  
2. var worldPos = Camera.main.ScreenToWorldPoint (Input.mousePosition.x, transform.position.y);
3.  

I am met with the error : "Argument type ‘float’ is not assignable to parameter type ‘UnityEngine.Vector3’"

How would I constrain the movement on the y while allowing free movement on the x?

 

Thanks so much! I am new to unity so it really helps.

 

Hi, sorry for bringing up this old thread. I have one question, the joints target is being moved in Update(), shouldn't it move specifically in FixedUpdate() so it's in sync with physics?

This piece of code

Code (CSharp):

1.  
2.         // Update the joint target.
3.         if (m_TargetJoint)
4.         {
5.             m_TargetJoint.target = worldPos;
6.  
7.             // Draw the line between the target and the joint anchor.
8.             if (m_DrawDragLine)
9.                 Debug.DrawLine(m_TargetJoint.transform.TransformPoint(m_TargetJoint.anchor), worldPos, m_Color);
10.         }
11.  

 

Thank you for the answer!