Official New SubScene & ConvertToEntity workflows

Just adding a note that new Entities release doesn't work on 2019.2.0a6 due to missing API there (Edit: Unity just released 2019.2.0a7. New Entities do run with it ) New samples also run fine on 2019.1.0b4.

For Subscene samples, one has to hit the "Rebuild Entity Cache" on the sample scenes, otherwise new samples were really straight forward (I really dig the clarity on current samples).

 

I'm curious to try out this approach, especially in more complex scenarios to see how it holds up.

I've been thinking for a while about what a PureECS "prefab editor" could look like, and I haven't yet been able to imagine something good and user-friendly (that's not to say it's impossible; just that I personally couldn't come up with anything yet). So I think this conversion workflow has potential

More specifically, I'm thinking about what it would be like to create a very complex prefab with complex logic in it, such as an animated character with:

• a bone hierarchy (one entity per bone, and possibly one more entity for the entire "rig")
• hit boxes (one entity per collider)
• ragdoll setup (one entity per rigidbody and one more entity per collider, potentially. Maybe even one more entity per joint)
• a skinned mesh renderer
• a character controller capsule
• a "CharacterManager" component that has references to character Bones, Meshes, Materials and other Prefabs for all sorts of purposes (in the case of Meshes, Materials and Prefabs, they cannot live on a IComponentData so that would be something to think about. And in the case of Bone references, they would be references to the specific Bone entities of that character instance). How could those "references" be edited in GameObject mode and then converted to ECS?
• etc....

 

@Joachim_Ante, awesome work. Btw is that still long way to go to have pure entity editing at Scene? Will I able to edit current Game Object and entity together at the same Scene when this feature arrives?

 

This is good news!

 

Awesome to see how ECS-in-editor crucial pieces are coming together now.

 

Hi, Can I use this new subscene system for partly streamed world? in example, load subscenes which is located nearby camera only. Current subscene systems seems that load all subscenes automatically. Can I customize loading strategy?

Also, how about scene-related asset, especially lightmap. I baked lightmap with subscenes, but it disappeared when I play it. (maybe automatically converted RenderMesh does not support lightmap yet?)

 

I hit the "like" button so hard my mouse exploded.

 

Have no time to test it, because new release completly broke every thing And I spend all time to repair (from 0.0.24 to 0.0.26 package)

 

I got my stuff back in working order again last night. Will take a crack at modifying it to use the new conversion tools tonight or tomorrow night.

 

Yep, me too. Finally migrate and fix all from 2018.3 to 2019.1 and 0.0.24 to 0.0.26

 

So I've been using scene conversion since p22 or whenever it was added. With p26 I've converted this over to new sub scenes (which only took minutes) so it hasn't been a huge change in my workflow.

Anyway here's a few notes, using Unity: 2019.1b5, in no particular order.

1. Keep getting a UI elements / serialization exception if I have the SubScene script selected when playing a scene.

Code (CSharp):

1. ArgumentException: Object at index 0 is null
2. UnityEditor.SerializedObject..ctor (UnityEngine.Object[] objs, UnityEngine.Object context) (at C:/buildslave/unity/build/Editor/Mono/SerializedObject.bindings.cs:39)
3. UnityEditor.Editor.GetSerializedObjectInternal () (at C:/buildslave/unity/build/Editor/Mono/Inspector/Editor.cs:545)
4. UnityEditor.Editor.get_serializedObject () (at C:/buildslave/unity/build/Editor/Mono/Inspector/Editor.cs:452)
5. UnityEditor.UIElements.InspectorElement..ctor (UnityEditor.Editor editor, UnityEditor.UIElements.InspectorElement+Mode mode) (at C:/buildslave/unity/build/Editor/Mono/Inspector/InspectorElement.cs:133)
6. UnityEditor.UIElements.EditorElement.Init () (at C:/buildslave/unity/build/Editor/Mono/Inspector/EditorElement.cs:47)
7. UnityEditor.UIElements.EditorElement..ctor (System.Int32 editorIndex, UnityEditor.InspectorWindow iw) (at C:/buildslave/unity/build/Editor/Mono/Inspector/EditorElement.cs:31)
8. UnityEditor.InspectorWindow.DrawEditors (UnityEditor.Editor[] editors) (at C:/buildslave/unity/build/Editor/Mono/Inspector/InspectorWindow.cs:1358)
9. UnityEditor.InspectorWindow.RebuildContentsContainers () (at C:/buildslave/unity/build/Editor/Mono/Inspector/InspectorWindow.cs:613)
10. UnityEditor.InspectorWindow.RedrawFromNative () (at C:/buildslave/unity/build/Editor/Mono/Inspector/InspectorWindow.cs:293)
11.  

Seems harmless just annoying as it trips 'error pause' entering play mode.

2. Is there an automated way to handle lights (or other non convertible game object components) that I've missed?

I currently use a custom game object conversion system

public class LightConversion : GameObjectConversionSystem

and a custom System that initializes them.
https://gist.github.com/tertle/5eb0084404a8dc69616ed37699b0fd23

3. TransformConversion has caused me a few issues.

It adds a Translation/Rotation proxy to entities which is an issue if your entity already has the proxy!

Previously I had a few GameObjectEntity prefabs that I had both in scene and I also used at runtime. This means I either had to remove the proxies when I put the object in a scene, or add the proxies when I initialized them at runtime.
Instead I just overrode the TransformConversion with a custom version that did a check before adding the component.

https://gist.github.com/tertle/b70563c21e12452038aa14805d7f3d87

This is based off the previous version of TransformConversion (p24) and I know it's been updated in p26 but I've stopped using it so it's just legacy pulled from repo.

Instead of doing this now though, I've decided to ditch ComponentDataProxies completely and just rely on IConvertGameObjectToEntity, so this isn't an issue for me anymore but others might run into it.

4. Overall, pretty happy with the system, it plugs in nicely to my preferred workflow. I'm pretty sure I had some other feedback when I was converting yesterday but I've just woken up and forgotten. I'll post more as I remember.

 

Well that's good because I decided to stop using them after this update and converted them to IConvertGameObjectToEntity MonoBehaviours instead. Is that the recommended workflow?

 

That's a really good call. The current HybridECS workflow involving GameObjectEntity and ComponentDataProxy has too much coupling between GameObjects and Entities, and frankly too much performance bog in the OnEnable & OnDisable.

Thinking those will be replaced sooner or later, I also converted everything to be using IConvertGameObjectToEntity yesterday and today (effectively getting rid of all GameObjectEntity and managing GO-to-entity relations on my own). Now there's much better separation between GOs and entities. Using the entity spawner pattern also feels really good and natural. In general, very happy with this release.

 

how about the subscene work with asset bundle. I see the cache data is store in resource folder.

 

Right now all the conversion methods will include Translation and Rotation in the resulting entity prefab. However, one of the advantages of using entity prefabs should be the ability to exclude transform data. Will this be supported in future APIs? Either through new conversion options or the aforementioned "dedicated entity editing tools"?

 

How can I have existing monobehaviours or components (eg BoxCollider) on a prefab that I pass into
GameObjectConversionUtility.ConvertGameObjectHierarchy

I'm guessing I should create my own component to represent the BoxCollider and add that to the entity with
IConvertGameObjectToEntity, then use a system to create a gameobject and put a box collider on it then attach it to the entity with EntityManager.AddComponentObject()

I tried using EntityManager.AddComponentObject in IConvertGameObjectToEntity but it didn't work, Note I'm trying this with a prefab into GameObjectConversionUtility.ConvertGameObjectHierarchy then EntityManager.
Instantiate to make copies of it. Is that the wrong flow?

 

Here's an example I just happened to see. You have to implement the Convert method in the IConvertGameObjectToEntity and then looks like you do AddComponentData instead of AddComponentObject.

https://github.com/Unity-Technologi...JobProcessComponentData/RotationSpeedProxy.cs

 

@Joachim_Ante - adding to @Creepgin's question, will there be (or is there already a timetable for) something like a ConvertScriptableObjectToEntity pipeline?

 

Please add abstraction layer for handling asset pipeline, not directly using addressables. Current addressables are lack of many important features like error handling, runtime re-initialization, encryption and so on. I think that making users can use their own asset management system will be more good way.

 

That really sounds more like feature request for addressables themselves.

 

Me too, most game project has it own asset management system and it may not suitable for switching to addressable system.

 

What's the end product of this? You want any arbitrary ScriptableObject asset file in Project folder/connected in the scene to become 1 Entity with 1 component object leading to that file?

 

Yeah also, I don't think you need a hierarchical conversion tool for ScriptableObjects because... they don't have a hierarchy. =D

But SO's-to-entity workflow is very powerful. And you can already do it today. If you serialize out your CompDatas (via Odin for example), you can create entities from SO's very easily:

Code (CSharp):

1. using Sirenix.OdinInspector;
2. using Unity.Entities;
3. using UnityEngine;
4. using System.Linq;
5. using System.Reflection;
6.  
7. [CreateAssetMenu(menuName = "ECS/SOEntityPrefab")]
8. public class SOEntityPrefab : SerializedScriptableObject {
9.  
10.     [SerializeField] IComponentData[] componentDatas;
11.  
12.     MethodInfo SetComponentDataMethod = typeof(EntityManager).GetMethod("SetComponentData", BindingFlags.Instance | BindingFlags.Public);
13.  
14.     [Button(ButtonSizes.Gigantic)]
15.     void CreateEntity() {
16.         var em = World.Active.GetOrCreateManager<EntityManager>();
17.         var entity = em.CreateEntity(componentDatas.Select(c => new ComponentType(c.GetType())).ToArray());
18.         foreach (var cd in componentDatas) {
19.             var genericMethod = SetComponentDataMethod.MakeGenericMethod(cd.GetType());
20.             genericMethod.Invoke(em, new object[] { entity, cd });
21.         }
22.     }
23.  
24. }
25.  

This sample is more for editor/playmode testing. But you can easily create entity prefab for runtime usage as well.

 

More for the "single consistent way" of an interface + supporting functions, otherwise we'll all wind up hand rolling a solution.

 

Since there is a way to save a group of entities to an asset (which is what subscenes are using right?) could we build a "scriptable object" on top of that? Even convert SO->entities asset file->then expose as a singleton.

 

It's fine for transform system optimisations, but it's only adds Static component to entity in GameObjectConversionMappingSystem, but for example if we use our GO representation for some thing like - data storage after conversion to entity, which not require TRS, and this components just waste space inside chunk and memory itself (of course it's not so huge, but...) I mean idea of just pure data storage entity without any representations it's possible in future for conversion tool?
BTW I found time to test conversion tools and they really cool, I swich all my hardcoded archetypes and own conversion tool for prefabs to built-in conversion tool.

 

Oohhh that is interesting! I guess this data is blittable or at least usable from jobs? Going to be super handy when passing data to jobs thanks!

Also.. strings are immutable.. so.. store strings as blobs?

 

Oh good, I think I should refresh my knowledge in code part about Static ICD.

 

BlobAssets sounds exactly what I was thinking of, thanks!

 

New Entities and Hybrid packages now out on package manager. Entities 0.0.12-preview.27 got Blobs and ComponentQueryBuilder as new, other changes seem to be tweaks to the conversion workflow.

Edit: Release notes updated: https://github.com/Unity-Technologies/EntityComponentSystemSamples/blob/master/ReleaseNotes.md

 

I also noticed that release notes didn't tell anything about blobs, I'm guessing the implementation still incomplete despite some chunks of code being there for it?

 

Do we have an example of usage of the ConvertAndInjectGameObject conversion mode? What's its intended use?

 

As I started switching over the new GameObject conversion pipeline, I found out that I lost access to the GameObject's components like Camera, Light etc. On the other hand, it seems like I can use

Code (CSharp):

1. EntityManager.AddComponentObject(entity, GetComponent<Camera>());

within conversion and store the entity on my MonoBehaviour. Is this the expected way for linking? I need to have access to entity from Camera for rendering hooks and I need to access Camera from entity to duplicate it later in a customized way

 

Also, it seems like pre-caching of a ComponentGroup and using it with Entities.With is faster than the every frame build (which performs cache lookup on every call) of Entities.WithAll/WithAny/WithNone. Though we could use Entities.WithAll/WithAny/WithNone to pre-build the group.

 

Awsome work.
Could you add some more samples, one that actually runs on two different data set in a job.
for instance: Get every Enemies, and calculate distance between Player(s)

Thanks

 

Sorry for the dumb question, but I'm not quite sure how we're supposed to use this.
Is it supposed to be a way to still generally use the old structure (monobehaviors) for a lot of things in editor, and then have it all converted to ECS during runtime?

Does anyone have an example of an application of these features?

 

There are samples of it being used in different ways here: https://github.com/Unity-Technologies/EntityComponentSystemSamples

All the links in the first post point to them.