chore: initial commit

Assets/Feel/MMTools/Accessories/MMMovement/MMPreventPassingThrough2D.cs

@@ -0,0 +1,132 @@
+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+using UnityEngine.Serialization;
+
+namespace MoreMountains.Tools
+{
+	/// <summary>
+	/// Prevents fast moving objects from going through colliders by casting a ray backwards after each movement
+	/// </summary>
+	[AddComponentMenu("More Mountains/Tools/Movement/MMPreventPassingThrough2D")]
+	public class MMPreventPassingThrough2D : MonoBehaviour 
+	{
+		public enum Modes { Raycast, BoxCast }
+		/// whether to cast a ray or a boxcast to look for targets
+		public Modes Mode = Modes.Raycast;	
+		/// the layer mask to search obstacles on
+		public LayerMask ObstaclesLayerMask; 
+		/// the bounds adjustment variable
+		public float SkinWidth = 0.1f;
+		/// whether or not to reposition the rb if hitting a trigger collider 
+		public bool RepositionRigidbodyIfHitTrigger = true;
+		/// whether or not to reposition the rb if hitting a non trigger collider
+		[FormerlySerializedAs("RepositionRigidbody")] 
+		public bool RepositionRigidbodyIfHitNonTrigger = true;
+
+		[Header("Debug")]
+		[MMReadOnly]
+		public RaycastHit2D Hit;
+
+		protected float _smallestBoundsWidth; 
+		protected float _adjustedSmallestBoundsWidth; 
+		protected float _squaredBoundsWidth; 
+		protected Vector3 _positionLastFrame; 
+		protected Rigidbody2D _rigidbody;
+		protected Collider2D _collider;
+		protected Vector2 _lastMovement;
+		protected float _lastMovementSquared;
+		protected RaycastHit2D _hitInfo;
+		protected Vector2 _colliderSize;
+
+		/// <summary>
+		/// On Start we initialize our object
+		/// </summary>
+		protected virtual void Start() 
+		{ 
+			Initialization ();
+		} 
+
+		/// <summary>
+		/// Grabs the rigidbody and computes the bounds width
+		/// </summary>
+		protected virtual void Initialization()
+		{
+			_rigidbody = GetComponent<Rigidbody2D>();
+			_positionLastFrame = _rigidbody.position; 
+
+			_collider = GetComponent<Collider2D>();
+			if (_collider as BoxCollider2D != null)
+			{
+				_colliderSize = (_collider as BoxCollider2D).size;
+			}
+			
+			_smallestBoundsWidth = Mathf.Min(Mathf.Min(_collider.bounds.extents.x, _collider.bounds.extents.y), _collider.bounds.extents.z); 
+			_adjustedSmallestBoundsWidth = _smallestBoundsWidth * (1.0f - SkinWidth); 
+			_squaredBoundsWidth = _smallestBoundsWidth * _smallestBoundsWidth; 
+		}
+
+		/// <summary>
+		/// On Enable, we initialize our last frame position
+		/// </summary>
+		protected virtual void OnEnable()
+		{
+			_positionLastFrame = this.transform.position;
+		}
+
+		/// <summary>
+		/// On fixedUpdate, checks the last movement and if needed casts a ray to detect obstacles
+		/// </summary>
+		protected virtual void Update() 
+		{ 
+			_lastMovement = this.transform.position - _positionLastFrame; 
+			_lastMovementSquared = _lastMovement.sqrMagnitude;
+
+			// if we've moved further than our bounds, we may have missed something
+			if (_lastMovementSquared > _squaredBoundsWidth) 
+			{ 
+				float movementMagnitude = Mathf.Sqrt(_lastMovementSquared);
+
+				// we cast a ray backwards to see if we should have hit something
+				if (Mode == Modes.Raycast)
+				{
+					_hitInfo = MMDebug.RayCast(_positionLastFrame, _lastMovement.normalized, movementMagnitude, ObstaclesLayerMask, Color.blue, true);	
+				}
+				else
+				{
+					_hitInfo = Physics2D.BoxCast(origin: _positionLastFrame,
+						size: _colliderSize,
+						angle: 0,
+						layerMask: ObstaclesLayerMask,
+						direction: _lastMovement.normalized,
+						distance: movementMagnitude);
+				}
+
+				if (_hitInfo.collider != null)
+				{
+					if (_hitInfo.collider.isTrigger) 
+					{
+						_hitInfo.collider.SendMessage("OnTriggerEnter2D", _collider, SendMessageOptions.DontRequireReceiver);
+						if (RepositionRigidbodyIfHitTrigger)
+						{
+							this.transform.position = _hitInfo.point - (_lastMovement / movementMagnitude) * _adjustedSmallestBoundsWidth;
+							_rigidbody.position = _hitInfo.point - (_lastMovement / movementMagnitude) * _adjustedSmallestBoundsWidth;
+						}   
+					}						
+
+					if (!_hitInfo.collider.isTrigger)
+					{
+						Hit = _hitInfo;
+						this.gameObject.SendMessage("PreventedCollision2D", Hit, SendMessageOptions.DontRequireReceiver);
+						if (RepositionRigidbodyIfHitNonTrigger)
+						{
+							this.transform.position = _hitInfo.point - (_lastMovement / movementMagnitude) * _adjustedSmallestBoundsWidth;
+							_rigidbody.position = _hitInfo.point - (_lastMovement / movementMagnitude) * _adjustedSmallestBoundsWidth;
+						}                        
+					}
+				}
+			} 
+			_positionLastFrame = this.transform.position; 
+		}
+	}
+}