Resolved Cannot retrieve child entity from spawned entity?

Hello, I have a simple Agent prefab meant to move in the scene. That agent has a Capsule child with a MeshRenderer. The agent is then spawned as an entity and the MeshRenderer is converted as a RenderMeshArray.

I would like to access the Capsule child at runtime and change that material's color. I have tried accessing it through the agent entity's Child Buffer to retrieve the Capsule entity, but Unity throws me an error saying the entity doesn't have a Child buffer :

Code (CSharp):

1.  
2.                 var agentEntity = EntityManager.Instantiate(spawnerAspect.AgentPrefab);
3.  
4.                 Random r = new Random((uint)(1));
5.  
6.                 float rand = r.NextFloat();
7.  
8.                 var child = SystemAPI.GetBuffer<Child>(agentEntity)[0].Value;
9.                 SystemAPI.SetComponent(child, new HDRPMaterialPropertyBaseColor
10.                 {
11.                     Value = rand < profile.GenderRatio ? this.ColorToF4(UnityEngine.Color.blue) : this.ColorToF4(UnityEngine.Color.magenta)
12.                 });

While the Child BufferComponentData has clearly been added to the agent entity :



Any help to access the child entity would be appreciated. Thank you for your time.

 

I'm going through the exact same issue. Did you manage to fix that error?

 

Hello,

I couldn't find a way to properly access the Child entities themselves, but I did find a way to modify their components :

Code (CSharp):

1. EntityQuery childQuery = SystemAPI.QueryBuilder().WithAll<TheComponentToModify>().Build();
2.  
3.  
4.         new ModifyJob
5.         {
6.             Ecb = ecb.AsParallelWriter(),
7.             ChildQueryMask = childQuery.GetEntityQueryMask(),
8.         }.ScheduleParallel();
9.  
10.  
11.     [BurstCompile]
12.     private partial struct ModifyJob: IJobEntity
13.     {
14.         #region Vars
15.  
16.  
17.         public EntityCommandBuffer.ParallelWriter Ecb;
18.         public EntityQueryMask ChildQueryMask;
19.  
20.         #endregion
21.  
22.         #region Execute
23.  
24.         // To retrieve the parent, I use a custom apsect referencing its Entity inside
25.         [BurstCompile]
26.         public void Execute(ParentAspect parent, [EntityIndexInQuery] int sortKey)
27.         {
28.             //Each root prefab contains a LinkedEntityGroup, a list of all its entities.
29.             // We retrieve the entity containing the Component registered in the QueryMask and we edit its value
30.  
31.             this.Ecb.SetComponentForLinkedEntityGroup(sortKey, parentAspect.Entity, ChildQueryMask, new TheComponentToModify { Value = Whatever() });
32.         }
33.  
34.         #endregion
35.     }
36.  
37.