2D smooth top-down movement

Question

Hi. I'm new to unity. I don't know how to smotoh my top-down movement. Can someone help?

 void Update()
 {
     movement.x = Input.GetAxisRaw("Horizontal");
     movement.y = Input.GetAxisRaw("Vertical");
     mouse = cam.ScreenToWorldPoint(Input.mousePosition);
 }

 private void FixedUpdate()
 {
     rb.MovePosition(rb.position + movement * speed * Time.fixedDeltaTime);
     Vector2 lookDir = mouse - rb.position;
     float angle = Mathf.Atan2(lookDir.y, lookDir.x) * Mathf.Rad2Deg - 90f;
     rb.rotation = angle;
 }

Answer 1

Some static helper function, should be in its own class c# class, but you could put it on your player if you like. We are using a plane (assuming your level is flat) to simplify detection for where the mouse is. All mouse values will contain a "height" of zero (which is what i wanted, you can change this)

   // MouseHelper.cs
     static Plane plane = new Plane(Vector3.up, 0f);
 public static Vector3 GetWorldPosition()
         {
             if (cam != null)
             {
                 Ray ray = cam.ScreenPointToRay(Input.mousePosition);
 
                 if (plane.Raycast(ray, out float distanceToPlane))
                 {
                     return ray.GetPoint(distanceToPlane);
                 }
             }
 
             return Vector3.zero;
         }

player script: We are grabbing the input in the update method and storing it in a class field. In the fixed update we use the input to change the character position. This script assumes your "Up" is Y and your forward is Z.

   // playerscripts.cs
 vector3 motion;

     public void Update()
     {
 // grabbing our motion from update because it runs more frequently
             motion = GetMovementFromInput();
         }
 
 
         public void FixedUpdate()
         {
 // applying position/rotation changes when the physics engine runs because we are using Rigidbody.ApplyForce
             UpdatePlayerRotation(motion);
             UpdatePlayerPosition(motion);
        }
 private void UpdatePlayerRotation(Vector3 motion)
         {
             // get mouse pos
             var mousePos = MouseHelper.GetWorldPosition();
             
             // lock y to unit's current y
             var lookTarget = new Vector3(mousePos.x, gameObject.transform.position.y, mousePos.z);
             
             Owner.transform.LookAt(lookTarget);
         }
 
 // i'm using the new input system... you can sub out the input.horizontal and forward for what you have now- Input.GetAxis("Horizontal")
         private Vector3 GetMovementFromInput(InputValues input)
         {
             var posX = input.Horizontal * movementSpeed * Time.deltaTime;
             var posY = 0;
             var posZ = input.Forward * movementSpeed * Time.deltaTime;
 
             var motion = new Vector3(posX, posY, posZ);
             return motion;
         }
 
         private void UpdatePlayerPosition(Vector3 motion)
         {
         rb.AddForce( motion.normalized * movementSpeed);
         }

Hope it helps =)

2D smooth top-down movement

1 Reply

Your answer

Follow this Question

Related Questions