Question How do I query for a DynamicBuffer in idiomatic foreach? DOTS 1.0

It indeed is, simply:

Code (CSharp):

1. foreach (var elements in SystemAPI.Query<DynamicBuffer<MyElement>>()){
2.     foreach (var element in elements) {
3.         Debug.Log(element);
4.     }
5. }

 

RefRO and RefRW are struct : IComponentData only.

Managed comps, dynamic buffers, aspects etc. are simply typed directly.

So a buffer queried is always accessed as RW.

 

Not nesscarirly, tho it is a great way! There are two other ways if you want to still type it directly.
The simplest one is this:

Code (CSharp):

1. public void OnUpdate(ref SystemState state) {
2.   var myElementsLookup = SystemAPI.GetBufferLookup<MyElement>(true);
3.   foreach (var (entity, myComp) in Query<RefRO<MyComp>>().WithAll<MyElement>().WithEntityAccess()) {
4.     var myElements = myElementsLookup[entity];
5.     foreach (var element in myElements){
6.       Debug.Log(element);
7.     }
8.   }
9. }

or the more preferred in this case (as to not do a lookup):

Code (CSharp):

1. BufferTypeHandle<MyElements> myElementsHandle;
2. public void OnCreate(ref SystemState state){
3.   myElementsHandle = GetBufferTypeHandle<MyBufferElement>(true);
4. }
5. public void OnUpdate(ref SystemState state){
6.   myElementsHandle.Update(ref state);
7.   var myQuery = SystemAPI.QueryBuilder().WithAll<MyElement>().Build();
8.   var chunks = myQuery.ToArchetypeChunkArray(WorldUpdateAllocator);
9.   foreach (var chunk in chunks) {
10.     var myElementsLookup = chunk.GetBufferAccessor(myElementsHandle);
11.     var entityCount = chunk.Count;
12.     for (int i = 0; i < entityCount; i++) {
13.       var myElements = myElementsLookup [i];
14.       foreach (var element in myElements) {
15.         Debug.Log(element);
16.       }
17.     }
18.   }
19. }

In anycase, we're aware and will look at better ways to do this in the future!