Unity - Move the Player Using Scripts Part 2

Get the gameObject's axis value

To move the character, you have to apply force to them by either changing the gameobject's velocity or by applying force to them.

• After getting the component from Awake(), you can manipulate it in the FixedUpdate() to move it.

      Rigidbody2D rigid;
  
      float h;
      public float walkSpeed;
  
        private void Awake()
      {
          rigid = GetComponent<Rigidbody2D>();
      }
  
      private void FixedUpdate()
      {
          h = Input.GetAxisRaw("Horizontal");
  
          rigid.velocity = new Vector2(h * walkSpeed, rigid.velocity.y);
      }

• In the FixedUpdate, we need a variable to store our Input.GetAxisRaw code.

Input.GetAxisRaw gets the value of virtue axis. For this case, -1 or 1 for x-axis.

• To store our Input.GetAxisRaw, we declare h as our float value before Awake() and set h = Input.GetAxisRaw("Horizontal")

• "Horizontal" is unity's built in system which captures the gameObjects horizontal movements. By default it is set to left arrow & right arrow and a & d keys on the keyboard.
• This can be found on Edit -> Project Settings -> Input Management.

• As you can see there's a lot of other inputs that we can use.
• If you want to change the number of inputs, you can change the size number.

Apply the velocity to the Rigidbody 2D

  Rigidbody2D rigid;

      float h;
      public float walkSpeed;

        private void Awake()
      {
          rigid = GetComponent<Rigidbody2D>();
      }

      private void FixedUpdate()
      {
          h = Input.GetAxisRaw("Horizontal");

          rigid.velocity = new Vector2(h * walkSpeed, rigid.velocity.y);
      }
  }

• Now we need to write a code to change the velocity of the gameObject.

  rigid.velocity = new Vector2(h * walkSpeed, rigid.velocity.y);

• We are going to tap in to our rigidbody 2D's velocity so write rigid.velocity

• Since we want to specify our Vector2, we will use new Vector2

new Vector2 is used when we need to create a new Vector2 with specific x and y components.

• For our x-axis value, we will use h value which is -1 or 1, since we want to move from left to right.

• For our y-axis value, we don't want to move vertically when we move horizontally. Therefore, we will leave it as it is. This can be done by rigid.velocity.y.

rigid.velocity = new Vector2(h, rigid.velocity.y);

• Our gameObject can move with this code, but it will only move at -1 or 1 speed becuase of our h value which is our Input.GetAxisRaw("Horizontal") value.

• We can solve this problem by making another variable called public float walkSpeed; before Awake().

• By making public float walkSpeed; public, we can access it from the gameObject's script section from the inspector window.

• Now, we can multiply the walkSpeed to our h value to make it go faster.

rigid.velocity = new Vector2(h * walkSpeed, rigid.velocity.y);

Make sure to save the script before playing the scene!

Constraints

• When you start moving, the gameObject might rotate.

• This can be fixed by freezing the gameObject's z-axis in constraints for Rigidbody 2D component.

Next

Apply force to the gameObject to move.