+ astar project

1 files changed, 110 insertions, 0 deletions

diff --git a/Other/AstarPathfindingDemo/Packages/com.arongranberg.astar/Behaviors/AIDestinationSetter.cs b/Other/AstarPathfindingDemo/Packages/com.arongranberg.astar/Behaviors/AIDestinationSetter.cs
new file mode 100644
index 0000000..5834f6f
--- /dev/null
+++ b/Other/AstarPathfindingDemo/Packages/com.arongranberg.astar/Behaviors/AIDestinationSetter.cs
@@ -0,0 +1,110 @@
+using UnityEngine;
+using Pathfinding.Util;
+#if MODULE_ENTITIES
+using Unity.Entities;
+#endif
+
+namespace Pathfinding {
+	/// <summary>
+	/// Sets the destination of an AI to the position of a specified object.
+	/// This component should be attached to a GameObject together with a movement script such as AIPath, RichAI or AILerp.
+	/// This component will then make the AI move towards the <see cref="target"/> set on this component.
+	///
+	/// Essentially the only thing this component does is to set the <see cref="Pathfinding.IAstarAI.destination"/> property to the position of the target every frame.
+	/// There is some additional complexity to make sure that the destination is updated immediately before the AI searches for a path as well, in case the
+	/// target moved since the last Update. There is also some complexity to reduce the performance impact, by using the <see cref="BatchedEvents"/> system to
+	/// process all AIDestinationSetter components in a single batch.
+	///
+	/// When using ECS, this component is instead added as a managed component to the entity.
+	/// The destination syncing is then handled by the <see cref="SyncDestinationTransformSystem"/> for better performance.
+	///
+	/// See: <see cref="Pathfinding.IAstarAI.destination"/>
+	///
+	/// [Open online documentation to see images]
+	/// </summary>
+	[UniqueComponent(tag = "ai.destination")]
+	[AddComponentMenu("Pathfinding/AI/Behaviors/AIDestinationSetter")]
+	[HelpURL("https://arongranberg.com/astar/documentation/stable/aidestinationsetter.html")]
+	public class AIDestinationSetter : VersionedMonoBehaviour
+#if MODULE_ENTITIES
+		, IComponentData, IRuntimeBaker
+#endif
+	{
+		/// <summary>The object that the AI should move to</summary>
+		public Transform target;
+
+		/// <summary>
+		/// If true, the agent will try to align itself with the rotation of the <see cref="target"/>.
+		///
+		/// This can only be used together with the <see cref="FollowerEntity"/> movement script.
+		/// Other movement scripts will ignore it.
+		///
+		/// [Open online documentation to see videos]
+		///
+		/// See: <see cref="FollowerEntity.SetDestination"/>
+		/// </summary>
+		public bool useRotation;
+
+		IAstarAI ai;
+#if MODULE_ENTITIES
+		Entity entity;
+		World world;
+#endif
+
+		void OnEnable () {
+			ai = GetComponent<IAstarAI>();
+#if MODULE_ENTITIES
+			if (ai is FollowerEntity follower) {
+				// This will call OnCreatedEntity on this component, if the entity has already been created.
+				follower.RegisterRuntimeBaker(this);
+			} else
+#endif
+			{
+				// Update the destination right before searching for a path as well.
+				// This is enough in theory, but this script will also update the destination every
+				// frame as the destination is used for debugging and may be used for other things by other
+				// scripts as well. So it makes sense that it is up to date every frame.
+				if (ai != null) ai.onSearchPath += UpdateDestination;
+
+				// Will make OnUpdate be called once every frame with all components.
+				// This is significantly faster than letting Unity call the Update method
+				// on each component.
+				// See https://blog.unity.com/technology/1k-update-calls
+				BatchedEvents.Add(this, BatchedEvents.Event.Update, OnUpdate, 0);
+			}
+		}
+
+		void OnDisable () {
+#if MODULE_ENTITIES
+			if (world != null && world.IsCreated && world.EntityManager.Exists(entity)) {
+				world.EntityManager.RemoveComponent<AIDestinationSetter>(entity);
+			}
+			if (ai != null && !(ai is FollowerEntity)) ai.onSearchPath -= UpdateDestination;
+#else
+			if (ai != null) ai.onSearchPath -= UpdateDestination;
+#endif
+			BatchedEvents.Remove(this);
+		}
+
+#if MODULE_ENTITIES
+		void IRuntimeBaker.OnCreatedEntity (World world, Entity entity) {
+			// Do nothing except add the component. Actual syncing is handled by the SyncDestinationTransformSystem.
+			this.entity = entity;
+			this.world = world;
+			world.EntityManager.AddComponentData<AIDestinationSetter>(entity, this);
+		}
+#endif
+
+		/// <summary>Updates the AI's destination every frame</summary>
+		static void OnUpdate (AIDestinationSetter[] components, int count) {
+			for (int i = 0; i < count; i++) {
+				components[i].UpdateDestination();
+			}
+		}
+
+		/// <summary>Updates the AI's destination immediately</summary>
+		void UpdateDestination () {
+			if (target != null && ai != null) ai.destination = target.position;
+		}
+	}
+}