Why is my player movement code not working?

Question

I'm trying to make my 2D character able to float around the screen, but my code isn't working:

using UnityEngine;

public class playermovement : MonoBehaviour
{

    public float moveSpeed = 5f;

    public Rigidbody2D rb;

    Vector2 Movement;

    public Vector2 Movementspeed { get; private set; }

    // Update is called once per frame
    void Update()
    {
        Movement.x = Input.GetAxisRaw("Horizontal");
        Movement.y = Input.GetAxisRaw("Vertical");
    }

    void FixedUpdate()
    {
        rb.MovePosition(rb.position + (Movement * Movementspeed * Time.fixedDeltaTime));
    }
}

Answer 1

Let's go over what your code is doing, and perhaps we can point some things out.

You use the variable Movement to capture the input for each axis at each update frame:

void Update()
{
    Movement.x = Input.GetAxisRaw("Horizontal");
    Movement.y = Input.GetAxisRaw("Vertical");
}

Capturing this in a Vector2 makes sense since you're moving in 2d, and doing it in the Update callback makes sense since you want to read the input every frame. So far so good.

Then in fixed update, you're moving the position of the Rigidbody2d by doing so:

rb.MovePosition(rb.position + (Movement * Movementspeed * Time.fixedDeltaTime));

What is the value of the variable Movementspeed at this point? Unless you have used the property setter to give it a value from somewhere else, it would default to (0,0). So the value of the statement (Movement * Movementspeed * Time.fixedDeltaTime) will return 0. So essentially you're setting the position of the rigidbody to its current position.

But really think about what you're trying to do in that statement. Movement is a 2d vector that represents your direction of movement, Time.fixedDeltaTime ensures that we move by a consistent amount no matter the variance in time between fixed update calls, but what is the purpose of Movementspeed? You're doing a cross product here when I don't think you intend to. You don't really need to use another Vector2 to represent your speed, just use a float. Remember that any vector multiplied by a float just changes the magnitude of that vector. The direction stays the same.

So what you probably want to do here is:

rb.MovePosition(rb.position + (Movement * moveSpeed* Time.fixedDeltaTime));

where moveSpeed is the float variable you've defined at the top of the script.

Answer 2

I fixed it thanks for the help? it works now! this is how it ended up:

using UnityEngine;

public class playermovement : MonoBehaviour {

public float moveSpeed = 5f;

public Rigidbody2D rb;

Vector2 movement;



// Update is called once per frame
void Update()
{
    movement.x = Input.GetAxisRaw("Horizontal");
    movement.y = Input.GetAxisRaw("Vertical");
}

void FixedUpdate()
{
    rb.MovePosition(rb.position + movement * moveSpeed * Time.fixedDeltaTime);
}

}