chore: initial commit

Packages/com.opsive.behaviordesigner/Runtime/Groups/BehaviorTreeSystemGroup.cs

@@ -0,0 +1,80 @@
+#if GRAPH_DESIGNER
+/// ---------------------------------------------
+/// Behavior Designer
+/// Copyright (c) Opsive. All Rights Reserved.
+/// https://www.opsive.com
+/// ---------------------------------------------
+namespace Opsive.BehaviorDesigner.Runtime.Groups
+{
+    using Opsive.BehaviorDesigner.Runtime.Systems;
+    using Unity.Entities;
+    using UnityEngine;
+
+    /// <summary>
+    /// System group which runs all of the behavior tree systems.
+    /// </summary>
+    [UpdateInGroup(typeof(SimulationSystemGroup))]
+    [UpdateAfter(typeof(BeginSimulationEntityCommandBufferSystem))]
+    public partial class BehaviorTreeSystemGroup : ComponentSystemGroup
+    {
+        private bool m_Alive;
+
+        public bool Alive { get => m_Alive; }
+
+        /// <summary>
+        /// Disable the group if there are no behavior trees.
+        /// </summary>
+        [RuntimeInitializeOnLoadMethod]
+        private static void Init()
+        {
+            if (BehaviorTree.BehaviorTreeCount > 0) {
+                return;
+            }
+
+            var worlds = World.All;
+            for (int i = 0; i < worlds.Count; ++i) {
+                var systemGroup = worlds[i].GetExistingSystemManaged<BehaviorTreeSystemGroup>();
+                if (systemGroup == null) {
+                    continue;
+                }
+                systemGroup.Enabled = false;
+            }
+        }
+
+        /// <summary>
+        /// The group has been created.
+        /// </summary>
+        protected override void OnCreate()
+        {
+            base.OnCreate();
+
+            m_Alive = true;
+        }
+
+        /// <summary>
+        /// Update the system group.
+        /// </summary>
+        protected override void OnUpdate()
+        {
+            base.OnUpdate();
+
+            // Stop running if all trees have completed.
+            var systemHandle = World.GetExistingSystem<DetermineEvaluationSystem>();
+            var system = EntityManager.WorldUnmanaged.GetUnsafeSystemRef<DetermineEvaluationSystem>(systemHandle);
+            if (!system.Active) {
+                Enabled = false;
+            }
+        }
+
+        /// <summary>
+        /// The group has been destroyed.
+        /// </summary>
+        protected override void OnDestroy()
+        {
+            base.OnDestroy();
+
+            m_Alive = false;
+        }
+    }
+}
+#endif