How to calculate EntityCommandBuffer.Concurrent jobIndex with IJobChunk?

I am unsure of how to calculate the jobIndex needed for EntityCommandBuffer.Concurrent when using an IJobChunk. Does anyone know?

Code (CSharp):

1. struct Job : IJobChunk {
2.     public EntityCommandBuffer.Concurrent commandBuffer;
3.  
4.     public void Execute(ArchetypeChunk chunk, int chunkIndex, int firstEntityIndex) {
5.        var entities = chunk.GetNativeArray(entityType);
6.        for (var i = 0; i < chunk.Count; i++) {
7.            var entity = entities[i];
8.            var jobIndex = ?
9.            commandBuffer.AddComponent(jobIndex, entity, new Whatever());
10.        }
11.     }
12. }

 

You can just use the chunkIndex.

Alternatively you can always inject the thread index.

Code (CSharp):

1. [NativeSetThreadIndex]
2. private int ThreadIndex;

But yeah, just use chunkIndex.

 

Thanks. Do you know why they provide firstEntityIndex? What is that useful for?

 

Not sure, it was a new addition to IJobChunk in p23 so I'm sure they have some type of pattern in mind.

 

May be It like chunk.StartIndex which was removed in past I think