API Deprecation FAQ (0.0.23)

The singleton api isn't anything magic, it just does a regular entity lookup and an Assert Length == 1 kind of check.
Honestly, the Singleton api is a bit meh at the moment and I avoid it most of the time. I only use RequireSingletonForUpdate to do checks like this.

Code (CSharp):

1.         /// <inheritdoc/>
2.         protected override void OnCreateManager()
3.         {
4.             // Ensure only a single ActiveFaction is present.
5.             this.RequireSingletonForUpdate<ActiveFaction>();
6.         }
7.  
8.         /// <inheritdoc/>
9.         protected override void OnUpdate()
10.         {
11.                 // Because the RequireSingletonForUpdate<ActiveFaction> this will only ever have 1 entity.
12.                 this.Entities
13.                     .WithAll<ActiveFaction>()
14.                     .ForEach((ref Faction faction, DynamicBuffer<FactionFogData> fogData) =>

 

After upgrading to the latest preview 30 - 0.0.12 package version I get this error on game start:

and this

What does it mean?

 

That's usually an issue with Unity's Package Manager and Burst. Restarting the editor fixes it. If you still have problems, that might be a Burst compile error in your code.

 

@DreamingImLatios

Thanks a lot, that fixed the issue.
However, I can not make generic JobComponentSystem running after upgrade:

Code (CSharp):

1. public class NodeSharedSpriteRenderingSystem : SharedSpriteRenderingSystem<NodeSharedSprite> { ... }
2.  
3. public class SharedSpriteRenderingSystem<T> : JobComponentSystem where T : struct, ISharedComponentData, ISprite { ... }
4.  

, where ISprite is my custom interface.

OnCreateManager is the only method that is called. After that, no trace in the Entity debugger or any OnUpdate call.
When I exit the game the OnDestroy is called once.

What happens to this system?

 

It sounds like the EntityQueries you specify in OnCreate and the EntityQueries derived from nested IJobForEach jobs in the class do not match any chunks in your world. Thus Unity won't call OnUpdate.

 

Thank you!
For some reason (Job)ComponentSystem can not catch LocalToWorld component, so I can't render anything. I tried to add LocalToWorld to existing system which already uses Translation, and after that it breaks.
Is this known issue?

I attached sample project:
_LocalToWorldIssue.zip

If you run it, you will see CoordsToPositionSystem running:


But if you add LocalToWorld component in that way:

Code (CSharp):

1. public class CoordsToPositionSystem : ComponentSystem {
2.     ...
3.     protected override void OnUpdate(){
4.         ...
5.        Entities.ForEach((ref Coords coords, ref Translation position, ref LocalToWorld local) => {
6.             ...
7.        }
8.     }
9. }

then CoordsToPositionSystem will not run:

 

Trying to understand these new changes. In the FPS Sample they have:

Code (CSharp):

1.     int FindPlayerControlling(ref ComponentArray<PlayerState> players, Entity entity)
2.     {
3.         if (entity == Entity.Null)
4.             return -1;
5.  
6.         for (int i = 0, c = players.Length; i < c; ++i)
7.         {
8.             var playerState = players[i];
9.             if (playerState.controlledEntity == entity)
10.                 return i;
11.         }
12.         return -1;
13.     }

How would this be converted using the new ForEach stuff?

 

The only way we can access IBufferElementData in parallel now is to use IJobChunk, right?

So to access inside IJobChunkExecute we should initialize ArchetypeChunkBufferType wich can be get by EntityManager.GetArchetypeChunkBufferType(bool) where bool tells is it RO. But when you call ArchetypeChunk.GetBufferAccessor(ArchetypeChunkBufferType) chunk changes his version.

In my case i have NativeMultiHashMap<int, Data> that contains some index that matches the cell on a map and some Data that i need to update on matching cell. In Execute() of IJobChunk i need to iterate through all cells and call TryGetFirstValue(...) on hashmap. But befor call it i also need to call ArchetypeChunk.GetBufferAccessor(ArchetypeBufferType). And that produce changes of whole chunk. I understand that i can write complex logic inside which i will get BufferAccessors only at fist successfull hit in hashmap iteration. But this approach seems very dirty to me.

The question is: can it be done without changing whole chunk version?

 

No. You also can use GetBufferFromEntity.

 

Is it as efficient?

 

Yes. It’s lookup.

 

Is it still possible to work with hybrid ecs after these changes?
How would you iterate over a entity with a transform and some costume script on it first example?

 

Yep you can work with hybrid fine. Use latest .ForEach syntax for that on main thread. Also IJobForEachTransform still exists untill Unity find better replacement.

 

Hey thanks for the reply any chance for an example ,or maybe you can correct what im doing wrong here?

the SetOrientationToGroundNormal is a monobeahviour and i've tried coupling it with a transform to create a type so i can iterate over everything that has those two things


using UnityEngine;
using Unity.Entities;
public class SystemSetOrientation : ComponentSystem
{

struct Data : IJobForEach<Transform,SetOrientationToGroundNormal>
{
public Transform transform;
public SetOrientationToGroundNormal orientation;
}


protected override void OnUpdate()
{


Entities.ForEach((IJobForEach<Transform> trans)=>
{
//do somehting
});
}
}

 

Code (CSharp):

1. using Unity.Entities;
2. using UnityEngine;
3.  
4. public struct MyComponent : IComponentData
5. {
6.     public int Val;
7. }
8.  
9. public class NewBehaviourScript : MonoBehaviour
10. {
11.     public int Val;
12. }
13.  
14. public class SystemIterator : ComponentSystem
15. {
16.     protected override void OnCreate()
17.     {
18.         var e = EntityManager.CreateEntity(typeof(MyComponent));
19.         EntityManager.SetComponentData(e, new MyComponent()
20.         {
21.             Val = 10
22.         });
23.      
24.         var go = new GameObject();
25.         go.transform.position = new Vector3(10, 11, 12);
26.      
27.         var monoComponent = (NewBehaviourScript)go.AddComponent(typeof(NewBehaviourScript));
28.         monoComponent.Val = 555;
29.      
30.         EntityManager.AddComponentObject(e, monoComponent);
31.         EntityManager.AddComponentObject(e, go.transform);
32.  
33.         monoComponent.Val = 999;
34.     }
35.  
36.     protected override void OnUpdate()
37.     {
38.         Entities.ForEach((Entity Entities, ref MyComponent c, Transform t, NewBehaviourScript m)=>
39.         {
40.             Debug.Log($"{t.position} - {m.Val} - {c.Val}");
41.             t.position += Vector3.up;
42.             m.Val += 10;
43.         });
44.     }
45. }
46.  

You of couse should use conversion workflow, I'm create GO from scratch just for showing example how ForEach works.

For access and change transform in job you should use IJobParallelForTransform with TransormAccessArray

 

Thanks so much for your help and time eizenhorn i really appreciate it , i understand what my mistake was, i kept doing a ref before component in the foreach paramaters and then i got the cannot put something that can be null error.
so i see now i only need to put the ref before the structs.

again thanks so much

 

How do I do this now?

Code (CSharp):

1. foreach(var e in GetEntities<Components>())
2. {
3.     // do something?
4. }

 

https://forum.unity.com/threads/api-deprecation-faq-0-0-23.636994/page-2#post-4478902

 

But direct access to buffer through chunks is more optimal then lookup through BufferFromEntity i guess.

 

1. @AriaBonczek or @Joachim_Ante I asked about determinism of GameObjectEntity in another thread. Some people mentioned there that GameobjectEntity is deprecated because things it relied on got deprecated. Is it true? If yes is there any built-in feature to keep the Gameobject and also a mapping between entity and gameobject.
   
   My main interest lies in making a deterministic simulation using a simple fixed point math lib and ECS and even hybrid mode is good enough for us and makes our job easier as well.
   
   How well it will be supported down the road and what approach should be used?
   
   We want to use ECS only for the simulation and not presentation of the game and the game has less than 20 units in the match at all points in time so memory / performance is not our explicit concern and determinism is.
   
   I know that we are not the most usual use-case but I want to see how much of the built-in infrastructure we can leverage and for example hopefully later on switch to burst deterministic floats instead of our fix64.
   Thanks

 

In the upgrade guide
https://github.com/Unity-Technologies/EntityComponentSystemSamples/blob/master/ReleaseNotes.md
0.0.23 Changes,
there is broken link in bullet point about [Inject] depreciation.
the Injection documentation

 

Hi Peeps, it's been a Year now (almost 11 months), are we waiting for the next Unite/Event before we get an update?

Also 19.3 doesn't seem to have any DOTS in the Package assets, was it removed ?
I'm referring to C# Jobs system, I do see the Burst Compiler, not that is shows on the Top of the Window (like it used to do before).

I'm just a newbie trying to keep up with it all.

 

There's been a few updates since they deprecated injection. The API is stabilizing on chunk iteration workflows, and GameObject conversion is the near-term authoring solution. The C# job system is built directly into Unity and has been out of preview for over a year now. Burst and Mathematics are packages which are also now out of preview. The other DOTS packages are Collections, Entities, Hybrid Renderer, Jobs (adds extra job types), Networking, and Physics.

 

Also the next unite is around the corner 25th IIRC and Mike Acton said on twitter that there will be updates and man I cannot wait for it.

Btw the current stuff are mostly stable in ECS as well

 

Darn, Looks like I need to reload an older Unity version, (not that I think it will help) - as They had the Demo's from the DOTS work flow, as you said, they may not be reliant now (deprecated).

This means I don't have much to go on as far are learning the DOTS system.
The AngryBots_ESC has been kept up to date (thank you Mike Geig and crew)

I have been able to glean info on the Chunk iteration ( 64 Kb memory chunks), thanks to some Youtube Digging.
The only person that I have found (outside Unity) on this is Code Monkey's DOTS videos.

I also found these videos series useful aswell, for the concept and implementation (whatever that means in this state)
https://www.youtube.com/channel/UCLD4SqNu97cJ7u19WMUeZCA/videos UnityDANZSEA

Hybrid Renderer, Entities have also disappeared, the thing is, they had content examples with them, once you installed - this would of been useful to me (newbie), but again, I would think that some C# code maybe depreciated by now.

Do you have any other Solid leads that can point to me the Relevant info or do we wait for the 25th ?

Thank you for your replies

 

I am not sure what you mean as I'm in 2019.3 and the latest package is from August 6 of this year.

We're using it for almost everything in our project and it is quite robust.

This also is not true. The Hybrid Renderer is still there, again an August 6 package.

Maybe you need to put the "all packages" filter on your Package Manager window?

 

August 6 package? Do you know what version of Unity you are using? My Guess would be latest official
release

 

Do you mean this? https://github.com/Unity-Technologies/EntityComponentSystemSamples

I've been doing a ton of stuff with DOTS these last few months (mostly game jams) and have been frequently scouring the internet for all things DOTS, but this never showed up for me so thanks for bringing it to my attention! https://github.com/UnityTechnologies/AngryBots_ECS

What Entities version shows up in Package Manager for you? If you don't see it, make sure you have selected All packages and under Advanced make sure you have enabled preview packages.

 

Latest Beta. You should not hide preview packages if you really want to use them (there is a setting on the window for that)