Having trouble with Player moving Left on his own

Unity Engine
1

Im trying to get my player to move Left right, and Jump. It worked for several days. Im helping students and must have accidently saved the wrong code or screwed something up in the player set up.
Here is the code. I also included player set up pictures.

8444540--1119584--Player Set up 1.jpg
8444540--1119584--Player Set up 1.jpg550Ă—1918 132 KB
8444540--1119587--Player Set up 2.jpg
8444540--1119587--Player Set up 2.jpg614Ă—2106 132 KB

public class PlayerMovement : MonoBehaviour
{

private Rigidbody2D rb;
private BoxCollider2D coll;//++++++++
private Animator anim;
private SpriteRenderer sprite;
private float dirX = 0f;
[SerializeField]
private LayerMask jumpableGround;//++++++++

[SerializeField]
private float moveSpeed = 7f;
[SerializeField]
private float jumpForce = 14f;

// Start is called before the first frame update
void Start()
{
rb = GetComponent();
coll = GetComponent();//++++++
}
// Update is called once per frame
void Update()
{
dirX = Input.GetAxisRaw(“Horizontal”);
rb.velocity = new Vector2(dirX * moveSpeed, rb.velocity.y);

if (Input.GetButtonDown(“Jump”) && isGrounded())//++++++++
{

rb.velocity = new Vector2(rb.velocity.x, jumpForce);
}

}
private bool isGrounded()
{
return Physics2D.BoxCast(coll.bounds.center, coll.bounds.size, 0f, Vector2.down, .1f, jumpableGround);
}
}

2

If you post a code snippet, ALWAYS USE CODE TAGS:

How to use code tags: Using code tags properly

Staring at static code can only take you a tiny part of the way to solving problems.

Here is how to reason about your code at runtime. This is a process known as debugging:

What is often happening in these cases is one of the following:

  • the code you think is executing is not actually executing at all
  • the code is executing far EARLIER or LATER than you think
  • the code is executing far LESS OFTEN than you think
  • the code is executing far MORE OFTEN than you think
  • the code is executing on another GameObject than you think it is
  • you’re getting an error or warning and you haven’t noticed it in the console window

To help gain more insight into your problem, I recommend liberally sprinkling Debug.Log() statements through your code to display information in realtime.

Doing this should help you answer these types of questions:

  • is this code even running? which parts are running? how often does it run? what order does it run in?
  • what are the values of the variables involved? Are they initialized? Are the values reasonable?
  • are you meeting ALL the requirements to receive callbacks such as triggers / colliders (review the documentation)

Knowing this information will help you reason about the behavior you are seeing.

You can also supply a second argument to Debug.Log() and when you click the message, it will highlight the object in scene, such as Debug.Log("Problem!",this);

If your problem would benefit from in-scene or in-game visualization, Debug.DrawRay() or Debug.DrawLine() can help you visualize things like rays (used in raycasting) or distances.

You can also call Debug.Break() to pause the Editor when certain interesting pieces of code run, and then study the scene manually, looking for all the parts, where they are, what scripts are on them, etc.

You can also call GameObject.CreatePrimitive() to emplace debug-marker-ish objects in the scene at runtime.

You could also just display various important quantities in UI Text elements to watch them change as you play the game.

If you are running a mobile device you can also view the console output. Google for how on your particular mobile target, such as this answer or iOS: How To - Capturing Device Logs on iOS or this answer for Android: How To - Capturing Device Logs on Android

Another useful approach is to temporarily strip out everything besides what is necessary to prove your issue. This can simplify and isolate compounding effects of other items in your scene or prefab.

Here’s an example of putting in a laser-focused Debug.Log() and how that can save you a TON of time wallowing around speculating what might be going wrong:

When in doubt, print it out!™

Note: the print() function is an alias for Debug.Log() provided by the MonoBehaviour class.

You must find a way to get the information you need in order to reason about what the problem is.

3

You should probably teach your students to use code tags when they ask questions, and use version control so they can roll back to earlier versions of their project.

1 Like