Move object perpendicular to the mouse position

In my code I have the player moving towards the mouse position when I press W and from the mouse position when pressing S. I also want the player to move left and right when I press A and D. However, I don't want the player to move left and right according to the X and Y-plane but relative to where the player is to the mouse position (the player rotates towards the mouse position at all times). So basically, when the player is rotated I want it to move perpendicular to it's direction to the mouse position when I press A or D.

This is my code for moving to/from the mouse:

Code (CSharp):

1.      void Update()
2.         {
3.             if (Input.GetKey(KeyCode.W))
4.             {
5.                 target = Camera.main.ScreenToWorldPoint(Input.mousePosition);
6.                 target.z = transform.position.z;
7.                 transform.position = Vector3.MoveTowards(transform.position, target, speed * Time.deltaTime);
8.             }
9.             if (Input.GetKey(KeyCode.S))
10.             {
11.                 target = Camera.main.ScreenToWorldPoint(Input.mousePosition);
12.                 target.z = transform.position.z;
13.                 transform.position = Vector3.MoveTowards(transform.position, target, -speed * Time.deltaTime);
14.             }
15.         }

It also rotates using the following code:

Code (CSharp):

1.     void Update()
2.         {
3.             //rotation
4.             Vector3 mousePos = Input.mousePosition;
5.             mousePos.z = 0;
6.  
7.             Vector3 objectPos = Camera.main.WorldToScreenPoint(transform.position);
8.             mousePos.x = mousePos.x - objectPos.x;
9.             mousePos.y = mousePos.y - objectPos.y;
10.  
11.             float angle = Mathf.Atan2(mousePos.y, mousePos.x) * Mathf.Rad2Deg;
12.             angle -= 90;
13.             transform.rotation = Quaternion.Euler(new Vector3(0, 0, angle));
14.             }
15.         }

 

Calculate the Vector3 from the player to the mouse and then the perpendicular vector. Following code is not tested but should be something like this:

1. Vector3 mousePos = Input.mousePosition;
2. mousePos.z = 0;
3. Vector3 objectPos = Camera.main.WorldToScreenPoint(transform.position);
   Vector3 perp = new Vector3(objectPos..y, objectPos.x, 0);
   Vector3 move = perp.normalized * speed;
   
   
   When pressing the left/right keys you have to move either along the "move" vector or the opposite direction.
   Hope it helps

 

It's missing a negation.
Either clockwise:

Code (CSharp):

1. Vector3 perp = new Vector3(objectPos.y, -objectPos.x, 0);

Or counter-clockwise

Code (CSharp):

1. Vector3 perp = new Vector3(-objectPos.y, objectPos.x, 0);

 

It's not really working. I think you made a mistake to begin with, since you never actually calculate the vector between the mouse and the object's position. I redid the code a bit and got this:

Code (CSharp):

1. Vector3 mousePos = Input.mousePosition;
2.         mousePos.z = 0;
3.         Vector3 objectPos = Camera.main.WorldToScreenPoint(transform.position);
4.         Vector3 n1 = mousePos - objectPos;
5.         Vector3 perp = new Vector3(n1.y, n1.x, 0);

and then:

Code (CSharp):

1. if (Input.GetKey(KeyCode.A))
2.         {
3.             transform.position = Vector3.MoveTowards(transform.position, -perp, speed * Time.deltaTime);
4.         }
5.         else if (Input.GetKey(KeyCode.D))
6.         {
7.             transform.position = Vector3.MoveTowards(transform.position, perp, speed * Time.deltaTime);
8.         }

It works as long as the player is moving along the x and y-axis. However, if I'm moving 45 degrees (my player always follows the mouse position) it's not working. Then the player just continues to walk towards/from the mouse if I press A or D.

 

You also forgot what I had mentioned above. You have to not only switch, but also invert either the x or the y value.

I've written a quick example, which at least uses the correct perpendicular (clockwise) vector on a per-frame basis. If you want to eliminate the "rotate around" effect when you move sideways , you can do that of course.

Code (CSharp):

1. using UnityEngine;
2.  
3. public class CLASS_NAME : MonoBehaviour
4. {
5.     private Camera _mainCamera;
6.  
7.     [SerializeField]
8.     private float speed = 2f;
9.  
10.     private void Awake()
11.     {
12.         _mainCamera = Camera.main;
13.     }
14.  
15.     private void Update()
16.     {
17.         var mouseWorldPosition = _mainCamera.ScreenToWorldPoint(Input.mousePosition);
18.         mouseWorldPosition.z = 0f; // this should actually be transform.position.z in case your sprite is not located at z = 0
19.         // this is one way to rotate, right (x-axis) being the new forward
20.         transform.right = (mouseWorldPosition - transform.position);
21.    
22.         var movementVector = GetMovementVector();
23.         transform.Translate(movementVector * Time.deltaTime * speed);
24.     }
25.  
26.     private Vector2 GetMovementVector()
27.     {
28.         Vector2 movementDirection = Vector2.zero;
29.    
30.         // accumulates the input, use else if to only enable one key at a time
31.         if (Input.GetKey(KeyCode.A))
32.         {
33.             movementDirection.y -= 1f;
34.         }
35.         if (Input.GetKey(KeyCode.D))
36.         {
37.             movementDirection.y += 1f;
38.         }
39.         if (Input.GetKey(KeyCode.W))
40.         {
41.             movementDirection.x += 1f;
42.         }
43.         if (Input.GetKey(KeyCode.S))
44.         {
45.             movementDirection.x -= 1f;
46.         }
47.    
48.         return movementDirection.normalized;
49.     }
50. }

 

Yes you are right I wrote it a bit in a hurry (sorry).

 

Wasn't meant to be offending in any way. So there's no reason to say sorry Don't worry, we're all kind persons.

 

I didn't take it that way. Glad you got it working