Hybrid ECS Transform Synchronization

Hey All,

Is there a simple way to make it so that a GameObject's transform gets synchronized with the associated entity's Position/Rotation component datas?

Thanks,
Bryan

 

Yes. But may be little tricky. Look for keyword in this ECS forum, tween, tweening. You will get some idea, to start of.

 

It's super easy, just add either of these components depending on the direction you want to copy

CopyTransformFromGameObject for copying the GameObject to Position/Rotation components
CopyTransformToGameObject for copying the Position/Rotation components to GameObject

Found in Unity.Transforms.Hybrid

 

Thanks man!

 

How does this work with the GameObjectEntity? Isn't that the preferred way to work Hybrid? GameObjectEntity makes a Transform component in the ECS entity that you can manipulate.

 

Hey, @tertle have you found there is GC.Collect spike in the Profiler, when using the CopyTransformToGameObject?

 

I have the same issue. There are about 1000 objects with CopyTransformToGameObject and CopyTransformFromGameObject and it takes more then 1ms. Spikes appears randomly (possibly with a large number of operations per minute, adding a parent/child to this object). And a spike time is always the same and depends on the total number of these CTTGO/CTFGO entities. For example, if you have 10 thousand entities with CTTGO/CTFGO and you will add a parent to one of them, will cause a lag of 10ms.

Is this the way it should be or am I doing something wrong, maybe someone knows?

 

CopyTransform behaviours have been more or less replaced by the concept of hybrid components. Use those instead.

That being said, using hybrid components is always going to be slow. If you want real scalability get rid of your monobehaviours/gameobjects.

 

Internally CopyTransformToGameObjectSystem does this:

Code (CSharp):

1. protected override JobHandle OnUpdate(JobHandle inputDeps)
2.         {
3.             var transforms = m_TransformGroup.GetTransformAccessArray();
4.             var copyTransformsJob = new CopyTransforms
5.             {
6.                 LocalToWorlds = m_TransformGroup.ToComponentDataArrayAsync<LocalToWorld>(Allocator.TempJob, out inputDeps),
7.             };
8.  
9.             return copyTransformsJob.Schedule(transforms, inputDeps);
10.         }

GC comes from .GetTransformAccessArray(), which generates new transform access array if old one is invalid (when number of transforms != entities with transforms in query changes).

Best way to avoid it - allocate single transform access array, and do not alter it.

Here's a thread about it, maybe you'll find something useful.
But in any case this requires custom system to sync TRS around.
https://forum.unity.com/threads/imp...form-system-performance.1048907/#post-6784835