Physics.IgnoreLayerCollision

Description

Makes the collision detection system ignore all collisions between any collider in layer1 and any collider in layer2.

Note that IgnoreLayerCollision will reset the trigger state of affected colliders, so you might receive OnTriggerExit and OnTriggerEnter messages in response to calling this.

You can set the default values for your project for any layer combinations in the Physics inspector.

Additional resources: Physics.GetIgnoreLayerCollision,Physics.IgnoreCollision.

//Attach this script to a GameObject and make sure it has a Rigidbody component
//Make a second GameObject with a Collider to test collisions on. Make sure both GameObjects are the same on the y and z axes

//This script stops collisions between two layers (in this case layers 0 and 8). Set up a new layer in the Inspector window by clicking the Layer option.
//Next click “Add Layer”. Then, assign this layer to the second GameObject.

//In Play Mode, press the left and right keys to move the Rigidbody to the left and right. If your first GameObject is in layer 0 and your second GameObject is in layer 8, the collision is ignored.


using UnityEngine;

public class Example : MonoBehaviour
{
    //Set the speed number in the Inspector window
    public float m_Speed;
    Rigidbody m_Rigidbody;

    void Start()
    {
        //Fetch the Rigidbody component from the GameObject
        m_Rigidbody = GetComponent<Rigidbody>();
        //Ignore the collisions between layer 0 (default) and layer 8 (custom layer you set in Inspector window)
        Physics.IgnoreLayerCollision(0, 8);
    }

    void Update()
    {
        //Press right to move the GameObject to the right. Make sure you set the speed high in the Inspector window.
        if (Input.GetKey(KeyCode.RightArrow))
        {
            m_Rigidbody.AddForce(Vector3.right * m_Speed);
        }

        //Press the left arrow key to move the GameObject to the left
        if (Input.GetKey(KeyCode.LeftArrow))
        {
            m_Rigidbody.AddForce(Vector3.left * m_Speed);
        }
    }

    //Detect when there is a collision
    void OnCollisionStay(Collision collide)
    {
        //Output the name of the GameObject you collide with
        Debug.Log("I hit the GameObject : " + collide.gameObject.name);
    }
}