Best practice for immutable data?

I've now gotten a grasp of the basics with Unity ECS. I have proto with some characters moving around in a city. My next step is to pass waypoint data to these entities. I have currently predefined waypoints as empty game objects in the scene. Let's assume there will be around 1000 waypoints and that they will never change after scene load.

Question1: What would be the preferred way of allowing my character systems to access this data? I have been told that simple static data should be avoided, correct?

Question2: Should I convert the game object waypoints to some better format before allowing systems to use them? E.g. a native array or are game objects fine? After all, I would need to access the position of the waypoint.

Best, Hu

(sorry if this has already been discussed in some thread, I did try to search for similar topics but didn't find anything matching).

 

You can use the new BlobBuilder/BlobAssetReference API to embed shared immutable data inside your IComponentData.

 

How does it work?

 

It use shared immutable allocated data (stored in big preallocated place, total 256mb if I remember sources, but I’m not sure about this, should look at sources) and storing pointer on CD (wrapped to BlobAssetReference). In this case you not split data by multiple chunks (like SCD)

 

Documentation is basically non-existent. Look at Library\PackageCache\com.unity.entities@0.0.12-preview.32\Unity.Entities.Tests\BlobificationTests.cs for examples. The Unity Physics examples also show how to use it.

 

Very cool, thanks!

 

Oh important warning: make sure and use 'ref var' on everything when you are using these blobs. If you copy a struct into a local variable and access a BlobArray/Ptr on the copied struct you will be reading potentially garbage memory.

 

What benefits of using BlobArray? Better memory allocating/accessing? Where can we read about blobs? (in general in google, i know)

 

"Converting scene data to DOTS" talk from this weeks Unite has an example that exactly answers my question. Unity listens .