[Player] Add AI Pathfinding on a 2D grid to the player character

Assets/External/AstarPathfindingProject/ExampleScenes/ExampleScripts/MineBotAnimation.cs

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+using UnityEngine;
+
+namespace Pathfinding.Examples {
+	/// <summary>
+	/// Animation helper specifically made for the spider robot in the example scenes.
+	/// The spider robot (or mine-bot) which has been copied from the Unity Example Project
+	/// can have this script attached to be able to pathfind around with animations working properly.\n
+	/// This script should be attached to a parent GameObject however since the original bot has Z+ as up.
+	/// This component requires Z+ to be forward and Y+ to be up.\n
+	///
+	/// A movement script (e.g AIPath) must also be attached to the same GameObject to actually move the unit.
+	///
+	/// Animation is handled by this component. The Animator component refered to in <see cref="anim"/> should have a single parameter called NormalizedSpeed.
+	/// When the end of path is reached, if the <see cref="endOfPathEffect"/> is not null, it will be instantiated at the current position. However a check will be
+	/// done so that it won't spawn effects too close to the previous spawn-point.
+	/// [Open online documentation to see images]
+	/// </summary>
+	[HelpURL("http://arongranberg.com/astar/docs/class_pathfinding_1_1_examples_1_1_mine_bot_animation.php")]
+	public class MineBotAnimation : VersionedMonoBehaviour {
+		/// <summary>
+		/// Animation component.
+		/// Should hold animations "awake" and "forward"
+		/// </summary>
+		public Animator anim;
+
+		/// <summary>
+		/// Effect which will be instantiated when end of path is reached.
+		/// See: <see cref="OnTargetReached"/>
+		/// </summary>
+		public GameObject endOfPathEffect;
+
+		bool isAtDestination;
+
+		IAstarAI ai;
+		Transform tr;
+
+		protected override void Awake () {
+			base.Awake();
+			ai = GetComponent<IAstarAI>();
+			tr = GetComponent<Transform>();
+		}
+
+		/// <summary>Point for the last spawn of <see cref="endOfPathEffect"/></summary>
+		protected Vector3 lastTarget;
+
+		/// <summary>
+		/// Called when the end of path has been reached.
+		/// An effect (<see cref="endOfPathEffect)"/> is spawned when this function is called
+		/// However, since paths are recalculated quite often, we only spawn the effect
+		/// when the current position is some distance away from the previous spawn-point
+		/// </summary>
+		void OnTargetReached () {
+			if (endOfPathEffect != null && Vector3.Distance(tr.position, lastTarget) > 1) {
+				GameObject.Instantiate(endOfPathEffect, tr.position, tr.rotation);
+				lastTarget = tr.position;
+			}
+		}
+
+		protected void Update () {
+			if (ai.reachedEndOfPath) {
+				if (!isAtDestination) OnTargetReached();
+				isAtDestination = true;
+			} else isAtDestination = false;
+
+			// Calculate the velocity relative to this transform's orientation
+			Vector3 relVelocity = tr.InverseTransformDirection(ai.velocity);
+			relVelocity.y = 0;
+
+			// Speed relative to the character size
+			anim.SetFloat("NormalizedSpeed", relVelocity.magnitude / anim.transform.lossyScale.x);
+		}
+	}
+}