CollisionEffects.cs

using UnityEngine;
using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
using Janus;

[Serializable]
public class CollisionEffectRelationship
{
    public PhysicMaterial OtherMaterial;
    public bool IsContinuous;
    public float EffectInterval = .5f;
    public AudioClip SoundEffect;
    public GameObject VisualEffectPrefab;
    public TriggerHitLocationMode TriggerHitLocationMode;
}

[AddComponentMenu("Liberi/Collision Effects")]
[Script(ScriptRole.View)]
public class CollisionEffects : MonoBehaviour
{
    public CollisionEffectRelationship[] Relationships;

    Dictionary<PhysicMaterial, CollisionEffectRelationship> _relationshipsByMaterial;
    Dictionary<Collider, Vector3> _continuousContacts;

    void Awake ()
    {
        _relationshipsByMaterial = new Dictionary<PhysicMaterial, CollisionEffectRelationship>();

        foreach (var relationship in Relationships)
        {
            _relationshipsByMaterial.Add(relationship.OtherMaterial, relationship);
        }

        _continuousContacts = new Dictionary<Collider, Vector3>();
    }

    private void ApplyEffect (CollisionEffectRelationship relationship, Vector3 location)
    {
        if (relationship.SoundEffect != null)
            SoundPool.Play(relationship.SoundEffect, location);

        if (relationship.VisualEffectPrefab != null)
            Sync.SpawnLocal(relationship.VisualEffectPrefab, location);
    }

    IEnumerator ApplyContinuousEffect (CollisionEffectRelationship relationship, Collider other)
    {
        while (other != null && _continuousContacts.ContainsKey(other))
        {
            ApplyEffect(relationship, _continuousContacts[other]);

            yield return new WaitForSeconds(relationship.EffectInterval);
        }

        yield break;
    }

    void OnCollisionEnter (Collision collision)
    {
        if (!enabled)
            return;

        if (collision.collider == null)
            return;

        var otherMat = collision.collider.sharedMaterial;

        if (otherMat == null)
            return;

        CollisionEffectRelationship relationship = null;

        if (!_relationshipsByMaterial.TryGetValue(otherMat, out relationship))
            return;

        if (relationship.IsContinuous)
        {
            _continuousContacts.Add(collision.collider, collision.contacts[0].point);
            StartCoroutine(ApplyContinuousEffect(relationship, collision.collider));
        }
        else ApplyEffect(relationship, collision.contacts[0].point);
    }

    void OnCollisionStay (Collision collision)
    {
        if (!enabled)
            return;

        if (_continuousContacts.ContainsKey(collision.collider))
            _continuousContacts[collision.collider] = collision.contacts[0].point;
    }

    void OnCollisionExit (Collision collision)
    {
        if (!enabled)
            return;

        if (collision.collider == null)
            return;
    
        var otherMat = collision.collider.sharedMaterial;

        if (otherMat == null)
            return;

        CollisionEffectRelationship relationship = null;

        if (!_relationshipsByMaterial.TryGetValue(otherMat, out relationship))
            return;

        if (relationship.IsContinuous)
        {
            _continuousContacts.Remove(collision.collider);
        }
    }

    void OnTriggerEnter (Collider other)
    {
        if (!enabled)
            return;

        if (other.sharedMaterial == null)
            return;

        CollisionEffectRelationship relationship = null;

        if (!_relationshipsByMaterial.TryGetValue(other.sharedMaterial, out relationship))
            return;

        if (relationship.IsContinuous)
        {
            _continuousContacts.Add(other, PhysicsUtils.GetTriggerHitLocation(collider, other, relationship.TriggerHitLocationMode));
            StartCoroutine(ApplyContinuousEffect(relationship, other));
        }
        else ApplyEffect(relationship, PhysicsUtils.GetTriggerHitLocation(collider, other, relationship.TriggerHitLocationMode));
    }

    void OnTriggerStay (Collider other)
    {
        if (!enabled)
            return;

        if (!_continuousContacts.ContainsKey(other))
            return;

        CollisionEffectRelationship relationship = null;

        if (!_relationshipsByMaterial.TryGetValue(other.sharedMaterial, out relationship))
            return;

        _continuousContacts[other] = PhysicsUtils.GetTriggerHitLocation(collider, other, relationship.TriggerHitLocationMode);
    }

    void OnTriggerExit (Collider other)
    {
        if (!enabled)
            return;

        if (other.sharedMaterial == null)
            return;

        CollisionEffectRelationship relationship = null;

        if (!_relationshipsByMaterial.TryGetValue(other.sharedMaterial, out relationship))
            return;

        if (relationship.IsContinuous)
        {
            _continuousContacts.Remove(other);
        }
    }
}