Restart ecs simulation?

Is there an easy way to complete restart an ecs simulation? I tried variations on the following without success...

World.Active.EntityManager.DestroyEntity(World.Active.EntityManager.GetAllEntities());

World.Active.Dispose();

SceneManager.LoadScene(SceneManager.GetActiveScene().buildIndex, LoadSceneMode.Single);

Thanks, Bas

 

I am using DefaultWorldInitialization to do this for me. You still need to dispose old world and scenes.

Code (CSharp):

1.    
2. World.Active.Dispose();
3. SceneManager.LoadScene("Intro", LoadSceneMode.Single);
4. DefaultWorldInitialization.Initialize("Default World", false);
5.  

 

I recently blueprinted a full scene management framework so I won't be using this code much longer. I don't keep state in systems, so I don't actually dispose the world and create a new one.

Code (CSharp):

1. using Unity.Entities;
2. using UnityEngine.SceneManagement;
3.  
4. namespace Latios
5. {
6.     internal struct LatiosSceneChangeDummyTag : IComponentData { }
7.  
8.     [AlwaysUpdateSystem]
9.     internal class DestroyEntitiesSceneChangeSystem : SubSystem
10.     {
11.         private EntityQuery destroyQuery = null;
12.  
13.         protected override void OnCreate()
14.         {
15.             EntityQueryDesc desc = new EntityQueryDesc
16.             {
17.                 All = new ComponentType[]
18.                 {
19.                     typeof(LatiosSceneChangeDummyTag)
20.                 },
21.                 None = new ComponentType[]
22.                 {
23.                     typeof(SingletonTag),
24.                     typeof(DontDestroyOnSceneChangeTag)
25.                 }
26.             };
27.             destroyQuery                = GetEntityQuery(desc);
28.             SceneManager.sceneUnloaded += RealUpdateOnSceneChange;
29.         }
30.  
31.         protected override void OnUpdate()
32.         {}
33.  
34.         private void RealUpdateOnSceneChange(Scene unloaded)
35.         {
36.             if (unloaded.isSubScene)
37.                 return;
38.  
39.             //Why are add and remove inconsistent?
40.             EntityManager.AddComponent(EntityManager.UniversalQuery, typeof(LatiosSceneChangeDummyTag));
41.             EntityManager.DestroyEntity(destroyQuery);
42.             EntityManager.RemoveComponent<LatiosSceneChangeDummyTag>(EntityManager.UniversalQuery);
43.         }
44.     }
45. }

 

Thanks, this works for me, I just use

World.DisposeAllWorlds();

to get rid of our streaming worlds

 

I'm trying to destroy all my worlds without the restart.

Just calling

World.DisposeAllWorlds();

gives me this error (and a similar one for PresentationSystemGroup):

Does anyone know how to unregister the system groups from the ScriptBehaviourUpdateOrder or a better way to achieve the goal of destroying the worlds? I don't want to change scene, I just want to destroy the worlds and that's it.

Code (CSharp):

1. InvalidOperationException: Unity.Entities.SimulationSystemGroup has already been destroyed. It may not be used anymore.
2. Unity.Entities.ComponentSystemBase.CheckExists () (at Library/PackageCache/com.unity.entities@0.1.1-preview/Unity.Entities/ComponentSystem.cs:323)
3. Unity.Entities.ComponentSystemBase.ShouldRunSystem () (at Library/PackageCache/com.unity.entities@0.1.1-preview/Unity.Entities/ComponentSystem.cs:339)
4. Unity.Entities.ComponentSystem.InternalUpdate () (at Library/PackageCache/com.unity.entities@0.1.1-preview/Unity.Entities/ComponentSystem.cs:783)
5. Unity.Entities.ComponentSystemBase.Update () (at Library/PackageCache/com.unity.entities@0.1.1-preview/Unity.Entities/ComponentSystem.cs:284)
6. Unity.Entities.ScriptBehaviourUpdateOrder+DummyDelegateWrapper.TriggerUpdate () (at Library/PackageCache/com.unity.entities@0.1.1-preview/Unity.Entities/ScriptBehaviourUpdateOrder.cs:144)

 

By destroying your world you mean destroy all entities?

EntityManager.DestroyEntity(EntityManager.GetAllEntities());

removing systems:

ComponentSystemGroup.RemoveSystemFromUpdateList(ComponentSystemBase sys)

Find your system to remove:

World.GetExistingSystem(typeof(system))

 

Yes, but also all systems and whatever other world data there might be.

I found a way to make it work. I call:

World.DisposeAllWorlds ();

DefaultWorldInitialization.Initialize ("Default World", false);

As has been suggested, however, I also needed to call it from a coroutine that waits until the end of the frame.