Limit object motion on single axis. (or multiple axis)

Scripting
1

Hello. I’m trying to build a simple script to limit the motion of an object on a single axis. But I haven’t used unity in ages. And really don’t know what I’m doing. Might be helpful to know if there is a way to expand to restricting motion on multiple axis.

using UnityEngine;
using System.Collections;

public class Player : MonoBehaviour {

	public float PlayerSpeed;
	public GameObject ProjectilePrefab;
	
	
	
	
	// Update is called once per frame
	void Update () 
	{
		///need to limit motion between 6.5 and -6.5
		// Amount to move
		float amtToMove = Input.GetAxisRaw("Horizontal") * PlayerSpeed * Time.deltaTime;
		
		// Move player
		if Player.transform.position.x < 6.5  Player.transform.position.x > -6.5
		transform.Translate(Vector3.right *amtToMove);
		
		
		if (Input.GetKeyDown("space"))
		{
			//Fire projectile
			Vector3 position = new Vector3(transform.position.x, transform.position.y + (transform.localScale.y / 2));
			
			Instantiate(ProjectilePrefab, position, Quaternion.identity);
		
		
		
		}
	
	}
}
2

You’re looking for Mathf.Clamp

You should be able to clamp the position between two values every frame. Essentially, if the value is greater than the high number/less than the low number, it gets changed to the greater/lesser number, respectively.

3

Hrrmm… Yeah that’ll work. I’m not sure how to implement this with what I have.

using UnityEngine;
using System.Collections;

public class Player : MonoBehaviour {

	public float PlayerSpeed;
	public GameObject ProjectilePrefab;
	
	
	function Update ()
{		Player.transform.position.x = Mathf.Clamp(Time.time, 6.5, -6.5);
}
	
	// Update is called once per frame
	void Update () 
	{
		///need to limit motion between 6.5 and -6.5
		// Amount to move

		float amtToMove = Input.GetAxisRaw("Horizontal") * PlayerSpeed * Time.deltaTime;
		
		// Move player
		
		
		if (Input.GetKeyDown("space"))
		{
			//Fire projectile
			Vector3 position = new Vector3(transform.position.x, transform.position.y + (transform.localScale.y / 2));
			
			Instantiate(ProjectilePrefab, position, Quaternion.identity);
		
		
		
		}
	
	}
}
4

Also clamp doesn’t seem to work when I put it off on it’s own. It just wants to gravitate towards the higher of the two values.

5

This is easier if you set transform.position directly rather than using transform.Translate. You can calculate the clamped X position with code like this:-

newX = Mathf.Clamp(transform.position.x + amtToMove, -6.5, 6.5);

Then, set the position:-

transform.position.x = newX;