is pausing a ComponentSystem possible -- or something with similar effect?

Hello,

I'm looking into transforming an approach using

Job

s for a

GameObject

driven design of mine into ECS + Job s.

On this occasion I would like to be able to pause a

ComponentSystem

:

Imagine many big cubes each containing many small cubes: every big cube has a

World

giving an

EntityManager

and its contained small cubes have

Component

s. When a big cube is not in view of the players camera I would like to pause the

ComponentSystem

acting on the

Component

s of this big cubes small cubes. The reason being to reduce CPU workload where possible.

Is this possible or is something similar possible? -- how ?

Apologies for possibly missing ' and the plural s syntax.

Resources I've studied:
https://unity3d.com/learn/tutorials/topics/scripting/implementing-ecs?playlist=17117 timecode 5:48
https://github.com/Unity-Technologi.../blob/master/Documentation~/entity_manager.md
https://github.com/Unity-Technologi...emSamples/blob/master/Documentation~/world.md
https://github.com/Unity-Technologi...master/Documentation~/job_component_system.md
https://github.com/Unity-Technologi.../master/Documentation~/system_update_order.md
https://github.com/Unity-Technologi...lob/master/Documentation~/component_system.md

 

Depending of the approach:

You can either have group system, which require entities with certain tags. In such case, you have empty IComponentData tag in entity, without data. Then you just add / remove, to activate / deactivate entity, form being processed by such system.

Or, having bit set, when iterating through entities in a system and enable / disable it, accordingly, to process data, or not. Simply using if loop for that purpose.

First approach is specifically good, when you have tons of entities, but you don't need set tags every frame. Also, if you have many systems, which may be affected by similar entities groups.
Second approach may be more convenient, if you your state changes every frame on many entities.

 

Enabled = false

 

Hi, thank you! I'll try these approaches. I thought of adding/removing a component too but guessed it likely isn't a "good" approach from a performance perspective.

 

Adding / Removing empty IComponentData as tag, is apparently treated differently, than components with data.
Haven't tested, but I suspect, it is faster than creating entity from archetype.

Setting bit is the fastest to set, but you still have entity iterated through system, even don't need them.

 

Hi, thank you again! In your first answer you mention "group system" and you mention "tag". I thought this to be Unity-independent terms but now I found https://github.com/Unity-Technologi...blob/master/Documentation~/component_group.md . Did you mean this? So by tag you also mean to use

tag

s (like

layer

s)?

ComponentGroup

appears like my "logic culling" or "logic LOD" was thought of when designing these. So I would use a

ISharedComponentData

on each

Entity

(small cube) and then would use something like

m_Group.SetFilter(new SharedGrouping { Group = 1 })

,

m_Group

being a

ComponentGroup

and

Group

being the data of that. And I would also use

[URL='https://docs.unity3d.com/ScriptReference/GameObject.FindGameObjectsWithTag.html']FindGameObjectsWithTag[/URL]

?

 

Yep, ComponentGroup
GetComponentGroup
For example

Code (CSharp):

1. ComponentGroup group ;
2. group = GetComponentGroup
3.             (        
4.                 // typeof ( Disabled ), // Example of existing Disabled component data.
5.                 typeof ( TagComponentData ),
6.                 typeof ( SomeOtherComponentData )
7.             ) ;

But in this case, I wouldn't be using !SharedComponentData, nor filter.

 

Hi, thank you!

I'm now working on it and have created an "isInViewSystem" which calculates the distance of each big cube having a DistanceComponent to the "Main Camera" (note: I'm describing this in the terms of the original post, they are not big cubes actually). Now I want to create a System X which works with each small cube having a SharedComponentData which sets this SharedComponentsData value to 1 or 0 depending on the given distance in the main cube. For this I wanted the big cube be a world ("new World(name)") and assign the System X to this World.

Do you happen to know how I can assign

ComponentSystem

s to a world? Note: every big cube being like another they will each need to have the "same"

ComponentSystem

in their world, but that

ComponentSystem

only operating on the

World

s entities.

How can I accomplish this (other than figuring out Packages/com.unity.entities/Unity.Entities.Hybrid/Injection/DefaultWorldInitialization.cs) ?

 

I don't use ComponentSystem. I use IComponentSystem.
Each world can have own set of entities. Therefore, they can work independently.