Collider Script

using UnityEngine;
using System.Collections;
using System.Collections.Generic;

public class ColliderTester : MonoBehaviour
{
    // _________________________________________________________________________________
    // |                             !! IMPORTANT !!                                   |
    // | + Make sure you assign a rigid body component to the object with this script. |
    // | + Make sure you enable "Is Trigger" to the collider component.                |
    // |_______________________________________________________________________________|

    // This script is used to create an easy to identify list of objects the object's collider is currently in contact with.*
    // * To exclude objects from detection, assign them to layers and use the Physics menu to choose which layers intact with each other.
    // ** Be sure to check both sides of the layer chart as one layer can still be interacting with another from the other way around.

    // Performance low? Check how many OnTrigger calls this collider is making by enabling this.
    public bool DebugCollisionTests;

    // Since colliders may rely on an initial setting,
    // this allows us to communicate when we've settled in.
    public bool Initialized;
    private float InitializeTimer;
    private float InitializeClock = 0.5f;

    // Check to see if we're touching anything
    public bool HittingAnything;

    // If we don't need to check for direction, save ourselves the effort and don't.
    public bool CheckDirections;

    // This is ONLY for testing with the raycast. Layer chart is used for Triggers.
    public LayerMask RaycastMask;

    // If layers are being used properly, this should be all we need the majority of the time. :)
    public bool HitTop;
    public bool HitBottom;
    public bool HitLeft;
    public bool HitRight;

    // The list of colliders and their information.
    public List<ColliderDetected> ColliderDetectList = new List<ColliderDetected>();

    void Start()
    {
        // Make sure the list is completely clean before using it.
        ColliderDetectList.Clear();
    }

    // Add collider information to the CollisionList;
    void OnTriggerEnter(Collider collider)
    {
        if (DebugCollisionTests) // Marks in the debugger when collisions enter.
            Debug.Log("[  ] - OnTriggerEnter: " + gameObject.collider + " has entered " + collider.name);

        // Add the new detected collider to our list of colliders.
        // Adding the current collider allows for you to detect your distance and location from the object.
        ColliderDetectList.Add(new ColliderDetected(collider, gameObject.collider));

        // If we enter a trigger, update our collisions.
        if (CheckDirections)
            RaycastTest();
    }

    // Remove collider information from the CollisionList;
    void OnTriggerExit(Collider collider)
    {
        if (DebugCollisionTests) // Marks in the debugger when collisions exit.
            Debug.Log("[X] - OnTriggerExit: " + gameObject.collider + " has exited " + collider.name);

        // listCount allows us to go through each collider in the list so we know which one to remove when we find a match.
        int indexCount = 0;

        // Go through each colliderDetected in the ColliderDetectList to find a matching collider.
        // DO NOT IDENTIFY BY NAME.
        // COLLIDERS ARE ALWEAYS UNIQUE.
        foreach (ColliderDetected colliderDetected in ColliderDetectList)
        {
            // Check each collider
            if (colliderDetected.collider == collider)
            {
                // Remove a collider based off of it's index count number.
                ColliderDetectList.RemoveAt(indexCount);
                // Break away from foreach loop so it doesn't try to finish the list after it's been changed.
                break;
            }
            // Adjust the index count if we haven't found a match yet.
            // This is important so that once we do find a match, we can remove it.
            indexCount++;
        }

        // We exited a trigger, update our collisions.
        if (CheckDirections)
            RaycastTest();
    }

    void RaycastTest()
    {
        HitTop = false;
        HitBottom = false;
        HitLeft = false;
        HitRight = false;

        // Easy access to Ray directions.
        Ray Up = new Ray(transform.position, Vector3.up);
        Ray Down = new Ray(transform.position, Vector3.down);
        Ray Left = new Ray(transform.position, Vector3.right); // Don't change. Properly inversed.
        Ray Right = new Ray(transform.position, Vector3.left); // Don't change. Properly inversed.

        RaycastHit hit;

        // Check all four directions for a hit.
        if (Physics.Raycast(Up, out hit, transform.localScale.y / 2f, RaycastMask))
            HitTop = true;
        if (Physics.Raycast(Down, out hit, transform.localScale.y / 2f, RaycastMask))
            HitBottom = true;
        if (Physics.Raycast(Left, out hit, transform.localScale.x / 2f, RaycastMask))
            HitLeft = true;
        if (Physics.Raycast(Right, out hit, transform.localScale.x / 2f, RaycastMask))
            HitRight = true;
    }

    void Update()
    {
        if (!Initialized)
        {
            InitializeTimer = InitializeTimer + (1 * Time.deltaTime);
            if (InitializeTimer > InitializeClock)
                Initialized = true;
        }

        if (ColliderDetectList.Count > 0)
            HittingAnything = true;
        else
            HittingAnything = false;
    }

    // This class holds information for each collider detected.
    // Any information about the collision can be found here.
    [System.Serializable]
    public class ColliderDetected
    {
        private string name;         // Listed for easy debugging.
        private string tag;          // Listed for easy debugging.
        public Collider collider;    // Required.

        // Constructor for creating a new ColliderDetected.
        public ColliderDetected(Collider newCollider, Collider selfCollider)
        {
            name = newCollider.name;
            tag = newCollider.tag;
            collider = newCollider;
        }
    }
}