How do you get a BufferFromEntity or ComponentDataFromEntity without Inject?

Since there are plans to deprecate Inject, I would like to avoid it and use the non-inject way. But how do you do this? I've only known to use Inject for these two.

 

Pretty sure you can just call GetComponentDataFromEntity<Type>(bool isReadOnly) from your system's update

 

[Example] IJobProcessComponentDataWithEntity and IBufferElementData

 

could you please link a proof of that [Inject] going to be removed

as far as I know, only "group struct injection" going to be replaced with something better, and there is nothing wrong with injection itself

 

He probably was referring to the first page of this topic: https://forum.unity.com/threads/api-usability.550450/

 

Auto/reflection filled group structs
Field injection

Yep same thought.
easy to get confused, or misinterpret, if we are new.

 

yes, looks like I'm wrong and all injects go away

Here is a minimal example for GetComponentDataFromEntity without injection

Code (CSharp):

1.  
2. public struct A : IComponentData{ public int Value; }
3. public struct B : IComponentData{ public Entity OtherEntity;}
4.  
5. public class TestSys : JobComponentSystem{
6.  
7.   protected override JobHandle OnUpdate(JobHandle inputDeps){
8.     return new Job(){
9.         a = GetComponentDataFromEntity<A>() // read/write
10.     }.Schedule(this, inputDeps);
11.   }
12.  
13.   [BurstCompile]
14.   private struct Job : IJobProcessComponentData<B>{
15.     // beware of race conditions when ParallelForRestriction  disabled
16.     [NativeDisableParallelForRestriction] public ComponentDataFromEntity<A> a;
17.     public void Execute( [ReadOnly]ref B b){
18.       Entity e = b.OtherEntity;
19.       if( a.Exists( e) ){
20.         var v = a[e].Value + 1;
21.         a[e] = new A(){Value = v};
22.       }
23.     }
24.   }
25.  
26. }
27.  

 

And minimal example for DynamicBuffer

Code (CSharp):

1. public struct A : IComponentData{  public int Value; }
2. public struct BBuffer : IBufferElementData{
3.   public int Value;
4.   public static implicit operator int(BBuffer item) { return item.Value; }
5.   public static implicit operator BBuffer(int i) { return new BBuffer { Value = i }; }
6. }
7.  
8. public class TestSys : JobComponentSystem{
9.  
10.   protected override JobHandle OnUpdate(JobHandle inputDeps){
11.     return new Job(){
12.       BBuffers =  GetBufferFromEntity <BBuffer> (false) // read/write
13.     }.Schedule(this, inputDeps);
14.   }
15.  
16.   [BurstCompile]
17.   [RequireComponentTag ( typeof(BBuffer) ) ]
18.   private struct Job : IJobProcessComponentDataWithEntity<A>{
19.  
20.     // beware of race conditions when ParallelForRestriction disabled
21.     [NativeDisableParallelForRestriction] public BufferFromEntity <BBuffer> BBuffers;
22.  
23.     public void Execute( Entity e, int i, [ReadOnly] ref A a ){
24.       DynamicBuffer<BBuffer> buffer = BBuffers[e];
25.       if( buffer.Length>0 )
26.         buffer[0] = a.Value;
27.     }
28.   }
29. }

 

This forum is just so cool! Thanks!

 

I couldn't find GetBufferFromEntity(). I'm already using the latest of Unity.Entities.

 

https://forum.unity.com/threads/0-0...mentity-no-longer-public.587668/#post-3925294