archived-dots

[rotund token]

always returns default at index 0

[rustic rain]

yeah, I noticed

welp

just another 30 minutes down the drain xD

but at least, I got progress

Any idea btw regarding reaction on structural changes utilites from Unity?
As in, do some action on query during adding/removing component?

if that's smth to exist in 1.0
I'd be sooooo happy

Is there a way to create query with OR settings?
As in: query through all entities that have either X or Y component. As with WithAll<T>?

[rotund token]

what do you mean by that sorry

[rustic rain]

for example if I want to do some loop only once and only when certain component is added/removed

for cleanup/setting up smth

[rotund token]

thats what unity designed ISystemState components for

[rustic rain]

hm

I should look into it

[rotund token]

if you care about created/destroyed

there's

EntityManager.GetCreatedAndDestroyedEntities

[rustic rain]

nah, this is for adding/removing components

in this exact case it's for LineRenderer GO component
I need to disable/enable it everytime entity gets target component for movement

or loses it

[rotund token]

in entity world of just tracking it'd be like
added = GetEntityQuery(readonly<Movement>, exclude<LineRenderer>()
removed = GetEntityQuery(exclude<Movement>, readonly<LineRenderer>()

[rustic rain]

LineRenderer never goes away

since it's class, Entity world doesn't really know it's state

that's why I do such clean up queires

    [UpdateInGroup(typeof(TickSimulationSystemGroup))]
    public partial class MovementLineSystem : SystemBase
    {
        private struct UpdatedTag : IComponentData
        {
        }

        protected override void OnUpdate()
        {
            Entities.WithNone<DisableRendering>().ForEach((CompanionLineRenderer lineRenderer, in MoveTarget target) =>
            {
                Vector3[] positions = new Vector3[2] {target.value, lineRenderer.LineRenderer.transform.position};
                positions[0].z = -5f;
                positions[1].z = -5f;
                lineRenderer.LineRenderer.SetPositions(positions);
            }).WithoutBurst().Run();

            var em = World.EntityManager;
            Entities.WithNone<UpdatedTag>().WithNone<MoveTarget>()
                .WithStructuralChanges().ForEach((Entity e, CompanionLineRenderer line) =>
                {
                    line.LineRenderer.enabled = false;
                    em.AddComponentData(e, new UpdatedTag());
                }).Run();

            Entities.WithAll<UpdatedTag>().WithAll<MoveTarget>().WithStructuralChanges().ForEach(
                (Entity e, CompanionLineRenderer line) =>
                {
                    line.LineRenderer.enabled = true;
                    em.RemoveComponent<UpdatedTag>(e);
                }).Run();
        }
    }

right now it looks disgusting

[rotund token]

but it could ^_^

i mean otherwise you just need another component to represent line renderer enabled/disabled

[rustic rain]

that's what private UpdatedTag is for rn I guess

[muted field]

so unity won't allow IntPtr since i cannot use Marshal.PtrToStructure in jobs now i'm stuck

how do you get the values from pointers without that =/

[rotund token]

intptr is fine

[muted field]

but it wont allow this _node = (Node)Marshal.PtrToStructure(_nodePtr, typeof(Node));

in a job

[rotund token]

anyway don't use marshal, unity provides UnsafeUtility to do things like this

[muted field]

oh

[rotund token]

UnsafeUtility.AsRef<>()

is what you're looking for

[muted field]

not sure how i use that with intptr

[rotund token]

i wouldn't really use intptr

but to answer your question intptr.topointer()

will return the actual pointer

which is what all unity methods require

[muted field]

yeh i tried that too

oh there we go

so why do you not recommend intptr ?

i couldn't find a way to store a collection of Struct* as my hash map's values so i had to use IntPtr

[rotund token]

oh yep sure

that's a legit use

[muted field]

fair enough 😛

thanks for the help there, you're a real life saver 😄

[rotund token]

need any distraction atm

trying to repo a painful burst cache issue for unity atm that is doing my head in

[muted field]

not sure what that even means tbh 😄

[rustic rain]

is there a way to make Rider to format all additional options like WithAll<T>() or <WithNone<T>() on new line?
Can't find what setting is it

oh nvm, found it

[rotund token]

its the wrap chained method calls right?

chop always

[solemn hollow]

ooh i didnt know this setting existed. so glad i came around to join the discord

[rustic rain]

this is the one

[solemn hollow]

yes thank you i found it already!

Right now i am trying to get used to the new Debugging workflow for Entities and avoid the use of EntityDebugger. Overall i really like the flow of how i can debug things through the relations.
But what i always feel like is missing is filtering all Entities for a certain set of components. That was possible in the EntityDebugger but how can i achieve the same functionality in the new EditorWindows? Is there some way to Filter in the EntityHierarchy?

If there isnt this needs to be raised in the forums i think

[rustic rain]

kek

I just did this, and it's enough for me for now

forgot to add Components to it

[rotund token]

But what i always feel like is missing is filtering all Entities for a certain set of components. That was possible in the EntityDebugger but how can i achieve the same functionality in the new EditorWindows? Is there some way to Filter in the EntityHierarchy?
yeah this is missing

and makes it too limited to use atm

multi component searches still needs to be done via entity debugger

if you saw the 1.0 talk though they had a filter button on the hierarchy window so i'm hoping that brings back this type of behaviour

[solemn hollow]

they had this in earlier versions too. thats why i am so confused and searching for it everywhere

[rotund token]

atm the search field while it can search for components

always does an Any query with them

and also always includes prefabs/disabled components

making filtering more than 1 component pretty impossible

[solemn hollow]

whats the syntax for searching components?

ah found it:

[rustic rain]

hmmm

so I read through ISystemState, I get how it works, but I don't see how I can use to it so solve my problem

rn

I have LineRenderer which I need to enable during adding of MoveTarget component to entity

and which I also need to disable when MoveTarget is removed from entity

what I don't want to do

is to enable/disable it every update

so rn I have these little 2 queries which add tag to avoid doing it, but can I somehow avoid doing that and use ISystemSate features somehow?

            var em = World.EntityManager;
            Entities.WithNone<UpdatedTag>()
                .WithNone<MoveTarget>()
                .WithStructuralChanges()
                .ForEach((Entity e, CompanionLineRenderer line) =>
                {
                    line.LineRenderer.enabled = false;
                    em.AddComponentData(e, new UpdatedTag());
                })
                .Run();

            Entities.WithAll<UpdatedTag>()
                .WithAll<MoveTarget>()
                .WithStructuralChanges()
                .ForEach(
                    (Entity e, CompanionLineRenderer line) =>
                    {
                        line.LineRenderer.enabled = true;
                        em.RemoveComponent<UpdatedTag>(e);
                    })
                .Run();

I don't remove entity during this whole process anyhow

and while it works fine rn, I need to expand it into another logic:
I need to also disable LineRenderer when entity gets DisableRendering component

[solemn hollow]

as i understand it you want 3 queries:

1. Query : all: MoveTarget, CompanionlineRenderer ; None: UpdateTag
   2.Query : all: MoveTarget,CompLineRenderer, UpdateTag
   3.Query : all CompanionLineRenderer, UpdateTag ; none : MoveTarget

2. Query triggers the job that adds the Update Tag

3. Query does the actual Update

4. Query is responsible for removing the UpdateTag

[rustic rain]

UpdatedTag is just tag that tells that LineRenderer is in disabled state and I don't need to disable it again.

for now it only triggers on absence/presence of MoveTarget

but now I also need it to trigger on DisableRendering

so when this DisableRendering exists, LineRenderer should be disabled

and my pattern of doing it

feels very bad

Do you know a better one maybe?

[solemn hollow]

wait let me clarify. The job that is executed with the first query also enables the linerenderer and the job that is executed with the third query disables it

so if you have more conditions to be met on when to enable and disable the linerenderer you adjust the queries accoringly

[rustic rain]

hmmm, let me just explain it in depth
MoveTarget - component with float3 to which entity (spaceship) is moving to in world space (as in literally target to move to).
CompanionLineRenderer - is component with reference to LineRenderer component attached to companion game object of said entity.

While these 2 exist, I SetPositions on LineRenderer. like this:

                    Vector3[] positions = new Vector3[2] {target.value, lineRenderer.LineRenderer.transform.position};
                    positions[0].z = -5f;
                    positions[1].z = -5f;
                    lineRenderer.LineRenderer.SetPositions(positions);

and when MoveTarget doesn't exist, I need to disable LineRenderer, so it doesn't draw unupdated lines

Using UpdatedTag helped to avoid disabling/enabling LineRenderer every update

but now that I also got condition of DisableRendering

logic is getting very messy

[solemn hollow]

Still what i wrote above should apply. maybe im bad at explaining it sry

that update logic you do to the linerenderer executes with 2.Query

[rustic rain]

well yeah, that's how it works rn

but now that I also got DisableRendering

I either need more queries or better pattern

[solemn hollow]

you just need to adjust the queries. not more

[rustic rain]

yeah

I guess so

btw, is there some way to define all those WithNone, WithAll in separate variable?
I'm pretty sure there is

I don't remember how it's called tho

[solemn hollow]

there might be but im not using it with lambdas. would also like to know 🙂

[rustic rain]

oh yeah, that's how

[solemn hollow]

ah thats what you meant. i meant i dont know how to use EntityQuery / EntityQueryDesc inside a Entities.ForEach as a parameter

[rustic rain]

hm

yep, I don't see an option to include query in loop

sadge

bruh, adjusting query options also doesn't seem possible atm

            Entities.WithAny<>()
                .WithNone<Disabled>()
                .WithNone<MoveTarget>()
                .WithStructuralChanges()
                .ForEach((Entity e, CompanionLineRenderer line) =>
                {
                    line.LineRenderer.enabled = false;
                    em.AddComponentData(e, new Disabled());
                })
                .Run();

for this Query I need to run with pretty weird conditionals

[solemn hollow]

WithEntityQueryOptions()

[rustic rain]

if it was OOP it'd be if (!MoveTarget OR DisableRendering) {}

[rustic rain]

it's enum for smth else

[solemn hollow]

which option do you need?

[rustic rain]

this one

I want to add Disabled (prev: updatedTag) only under those conditions

[solemn hollow]

ok but that is not an available query option

[rustic rain]

so either when MoveTarget is absent or when DisableRendering is present

yeah

I figured

[solemn hollow]

you can combine queries for that to work

[rustic rain]

which forces me to add another query

kek

[solemn hollow]

EntityQuery query = GetEntityQuery(new EntityQueryDesc[] { desc1, desc2 });

[rustic rain]

but can I run EntityQuery in loop?

I didn't find a way for it

[solemn hollow]

well go with IJobEntity then

[rustic rain]

I can use it to create struct IJob, but that would be another pain

kinda wish I could stay within SystemBase

[solemn hollow]

IJobEntity is not a pain anymore.

actually better than Entities.Foreach imo. I just had some problems with the codegen so im not using it too much yet.

[rustic rain]

hm

I'm looking into it

[solemn hollow]

https://docs.unity3d.com/Packages/com.unity.entities@0.50/manual/ecs_ijobentity.html

You can declare the Execute method pretty much like you did with the entities.foreach and use the variables in the job. all the boilerplate is handled by codegen

[rustic rain]

Can I use entity manager there tho?

since all those queries are with structural changes

[solemn hollow]

Good Question. I only ever use CommandBuffers and havent used IJobEntity enough yet to tell you. Pretty sure you can use ECBs inside. Not sure about EntityManager

Do you really need to use EntityManager inside though? wouldnt it be better to use EntityManager.RemoveComponent<MyComponent>(myQuery)

[rustic rain]

well, aside from removing component

I also need to actually disable LineRenderer

So, maybe I don't

maybe I can combine it with different things

[solemn hollow]

the job that disables the linerenderer can still run. afterwards you remove the component. Probably better to defer that removal to an ECB though

[rustic rain]

oh man, that's why I simply wish Unity would implement some kind of reaction queries

to structural changes

xD

[solemn hollow]

i dont think its too hard atm. Once you did it a few times its quite logical

for reference you could look into unitys ParentSystem

[astral parrot]

Hi, me wanna ask, I have installed the animation for dots, but it seems there's an error on the data flow graph dependency, how to fix this?

[solemn hollow]

The package did not get updated with the last 0.50 release. Would be quite some work to get it running i guess.

[astral parrot]

So... does that mean I need to go back to previous version of entities?

Or is there anyway to work on animation?

[solemn hollow]

Some people made their own ECS animations. There should be sth about that in the Forums. The other option is to use GameObjects for animations.

[astral parrot]

hmmm... I'll find a way, tq for the info

[rustic rain]

Do I need to get EntityManager every update?

or can I store it in variable in OnCreate?

[solemn hollow]

You dont need to get it at all. SystemBase already has a reference to EntityManager

[rustic rain]

nah, I'm doing it with IJonEntity

just wondering whether I need to write to it's field it

or not

also kinda confused with queries

So from what I see

I can create EntityQuery from a lot of things

it can be ComponentType[] or EntityQueryDesc

meanwhile ComponentType itself can also be differen

any idea on their interaction with All, None and Any?

[rotund token]

you'll get errors if you use things like exclude in a description query instead of using none field

[rustic rain]

hm

[rotund token]

as for this, you shouldn't create them from EM unless you know what you're doing

Get in a system adds the dependency to the system

[rustic rain]

what I want rn is to create a Query with conditional

I need to go through entities that either have DisableRendering component or don't have MoveTarget component

so I either have cool query that specifies that, or I go through 2 different queries

[rotund token]

use an EntityQueryMask

What's an EntityQueryMask you say?

Get your entity query and call something like CreateEntityQueryMask

this then provides a very fast lookup if an entity matches a specific query

[solemn hollow]

but u still need to do the lookup though. isnt combining 2 queries better here?

[rustic rain]

How do I combine 2 queries?

Get one from 2 descriptions?

[rotund token]

oh yeah i slightly missread his requirement

you can make a multi query

[solemn hollow]

already showed you : EntityQuery query = GetEntityQuery(new EntityQueryDesc[] { desc1, desc2 });

maybe there is a nicer way to combine now? i just got this from the Docs

[rotund token]

i think that's the way

under the hood it just uses EntityQueryDescBuilder

so you could use that i guess

[rustic rain]

            var disabledDesc = new EntityQueryDesc();
            disabledDesc.All = new ComponentType[]
            {
                ComponentType.ReadWrite<CompanionLineRenderer>(), ComponentType.ReadOnly<DisableRendering>(),
            };
            disabledDesc.None = new ComponentType[] {ComponentType.ReadOnly<DisabledLR>(),};

            var secondDisabledDesc = new EntityQueryDesc();
            secondDisabledDesc.All = new ComponentType[] {ComponentType.ReadOnly<CompanionLineRenderer>(),};
            secondDisabledDesc.None = new ComponentType[]
            {
                ComponentType.ReadOnly<DisabledLR>(), ComponentType.ReadOnly<MoveTarget>(),
            };

            disableQuery = GetEntityQuery(disabledDesc, secondDisabledDesc);

soooo, like this?

[rotund token]

i hate the formatting but yeah sure

[rustic rain]

tips on formatting? xD

Actually have been tweaking with it a bit ago

[rotund token]

            {
                All = new[] { ComponentType.ReadWrite<CompanionLineRenderer>(), ComponentType.ReadOnly<DisableRendering>(), },
                None = new[] { ComponentType.ReadOnly<DisabledLR>() },
            };

            var secondDisabledDesc = new EntityQueryDesc
            {
                All = new[] { ComponentType.ReadOnly<CompanionLineRenderer>() },
                None = new[] { ComponentType.ReadOnly<DisabledLR>(), ComponentType.ReadOnly<MoveTarget>() },
            };

            disableQuery = GetEntityQuery(disabledDesc, secondDisabledDesc);```

is personally how i'd format it

            {
                All = new[]
                {
                    ComponentType.ReadWrite<CompanionLineRenderer>(), 
                    ComponentType.ReadOnly<DisableRendering>(),
                },
                None = new[] { ComponentType.ReadOnly<DisabledLR>() },
            };

            var secondDisabledDesc = new EntityQueryDesc
            {
                All = new[] { ComponentType.ReadOnly<CompanionLineRenderer>() },
                None = new[]
                {
                    ComponentType.ReadOnly<DisabledLR>(), 
                    ComponentType.ReadOnly<MoveTarget>()
                },
            };

            disableQuery = GetEntityQuery(disabledDesc, secondDisabledDesc);```

or if i need new lines

but entirely up to you - whatever you like

[rustic rain]

ok, so

this Query made from 2 descriptions

literally means that it will go through 2 queries

under the hood?

[rotund token]

yep

[rustic rain]

ok, that's great

[rotund token]

if an entity is in either query it will be returned by this

you won't know what query it's from so if you need to care about components conditionally

recommended to use IJobBatch and then use batch operations to check if a chunk as a compoent

so you can treat the whole chunk 1 way or another

[rustic rain]

I am learning IJobEntity rn

watched vid from Turbo

and got hyped by it

[rotund token]

you don't need no video

but yes ijobentity is great

[solemn hollow]

aside from no HasComponent 😦

[rotund token]

i actually write less than 10% of my jobs with entities.foreach

and this was before IJobEntity

i might legit never write an entities.foreach again that is longer than 4 lines

[pulsar jay]

Does WithChangeFilter automatically create a read dependency or would I have to do that manually?

[rustic rain]

oh well, seems like I can't use EntityManager in IJobEntity

or maybe I can

hmm

[solemn hollow]

with EntityManager you lose burst. use an ECB

[rotund token]

You shouldn't (use em in job)

[rustic rain]

I don't need burst

it's all working with class components anyway

[solemn hollow]

But i also already told you that you don't even need to remove components inside the job. you can do it outside for the whole query as a batched command

[rustic rain]

ah yes

forgot about it

wait hold on

I also need to add components

so no, I'd rather have my ability of EM somehow

in short, job looks like this rn xD

        private partial struct SetLineRendererJob : IJobEntity
        {
            public EntityManager em;
            public bool mode;

            private void Execute(Entity e, CompanionLineRenderer lineRenderer)
            {
                lineRenderer.LineRenderer.enabled = mode;
                if (mode)
                {
                    em.RemoveComponent<DisabledLR>(e);
                }
                else
                {
                    em.AddComponentData(e, new DisabledLR());
                }
            }
        }

[solemn hollow]

you can also add components in a batched fashion

[rustic rain]

I do?

[solemn hollow]

EntityManager.AddComponent<DisabledLR>(disableQuery)

[rustic rain]

yeah, I am looking into it

[solemn hollow]

Batched commands are ways faster since no memory has to be copied around. the whole chunk just gets another component

[rustic rain]

        private partial struct SetLineRendererJob : IJobEntity
        {
            // public EntityManager em;
            public bool mode;

            private void Execute(Entity e, CompanionLineRenderer lineRenderer)
            {
                lineRenderer.LineRenderer.enabled = mode;
                // if (mode)
                // {
                //     em.RemoveComponent<DisabledLR>(e);
                // }
                // else
                // {
                //     em.AddComponentData(e, new DisabledLR());
                // }
            }
        }
        protected override void OnUpdate()
        {
            updateJob.Run(updateQuery);

            setJob.mode = false;
            setJob.Run(disableQuery);
            EntityManager.AddComponent<DisabledLR>(disableQuery);

            setJob.mode = true;
            setJob.Run(enableQuery);
            EntityManager.RemoveComponent<DisabledLR>(disableQuery);
        }

looks a little bit silly, but let's try kek

well, no errors

[solemn hollow]

That makes no sense though. you are adding and then removing the same component on the same query

[rustic rain]

looks like it works, but my logic is flawed somewhere

oh

should be different queries

yay

looks like it works

thank you, sir

ok, now that's something

hmm, this now bugs me with some dependency error

            var translations = GetComponentDataFromEntity<LocalToWorld>(true);
            Entities.WithReadOnly(translations)
                .ForEach((Entity entity, ref MoveTarget moveTarget, in FollowShip ship) =>
                {
                    moveTarget.value = translations[ship.Entity].Position;
                }).Schedule();

How can I transform it into IJobEntity?

kind of get same behaviour of accessing random entity's component

this is the error

[solemn hollow]

just assign the jobhandle to the Systems Dependency field:
Dependency = Entities.ForEach....Schedule(Dependency)

[rustic rain]

but is there a way to achieve similiar thing with IJobEntity?

just curious

[solemn hollow]

Dependency = new MyJob().Schedule(Dependency)

[rustic rain]

no I mean

regarding reading translation of random entity?

[rustic rain]

aaand, that didn't help btw

[solemn hollow]

you need to pass ComponentDataFromEntity

[rustic rain]

same error

[rustic rain]

to a field?

[ionic sierra]

Hello. Quick question. If I "instantiate" soemthing in DOTS, can I then save the instantiated objects into my project folder as a prefab?

[solemn hollow]

    {
        public ComponentDataFromEntity<SpeedModifiers> modifiers;

        public void Execute(ref DynamicBuffer<ActiveEffect> activeEffect,in SpeedEffect speedEffect)
        {
            
        }
    }```

[solemn hollow]

not out of the box. Youd need to code that yourself

[ionic sierra]

ok then. I guess that helps. Thanks

[solemn hollow]

My question would be why you need this. Can't you just make a normal GameObject Prefab and convert it when u need it as an entity?

[rustic rain]

wait a second

that dependency error

it's about reading Entity

ahem

Do I need to somehow specify dependency on Entities list?

[ionic sierra]

I was thinking the same thing. It's more easier to work with GameObjects. But I guess if it is possible then it might be useful for letting for-instance a user to make a object and being able to save it at runtime.

[solemn hollow]

id need to see more of the system to help you

[rustic rain]

oddly, error shifted to my other system

xD

I'm not even sure whether it's me who did smth wrong

or just unity doing it's dirty things

but error looks like this

it says it reads Entity

type

[solemn hollow]

Yes same fix as before. Assign the Job to the System Dependency

@rotund token maybe knows under what circumstances unity handles those dependencies automagically and when not. i never got the pattern. i just always assign the dependencies when not sure

[rustic rain]

it says I read Entity

which makes me really curious

since I do indeed read Entity

as component

and in other system

I have Entity written inside component

which might potentially trigger some kind of race condition

[solemn hollow]

Well yes that is what its saying. but the weird part is that Entity should be Readonly right?

[rustic rain]

I kind of assumed it is

[solemn hollow]

i never had issues with the entities array and race conditions. So maybe Codegen of IJobEntity is flawed atm (forgot to make it readonly) or you make changes in the EntityManager which trigger this racecondition?

[rustic rain]

same error happened with ForEach loop

[solemn hollow]

okay so its probably you making structural changes while those jobs are running?

[rustic rain]

no

oh

maybe

[ionic sierra]

is there a DOTS learning resource?

[rustic rain]

moetsi has a very nice guide

Turbo Makes Games on YT

[ionic sierra]

is moetsi a youtube channel?

[rustic rain]

nah, it's a website

https://dots-tutorial.moetsi.com/

[ionic sierra]

thats great. seems like a lot of info

[solemn hollow]

plz dont start with multiplayer though.

[ionic sierra]

No , i wont. Luckily its got chapters on ECS and dots physics first.

[solemn hollow]

Do ISystemStateComponents have overhead? I am thinking about having an EffectEntity that has an ISystemStateBuffer to keep track of all effected Entities. Once the EffectEntity is destroyed every effected Entity needs to get the effect removed. Until now i only used ISystemStateComponents as Tags. Not sure if it is a good idea to keep data in them that i need both for update and cleanup.

Well i guess since unity is using a SystemStateBuffer for their Child component i guess its fine to use it in my case.

[pulsar jay]

I am thinking about creating a generic timer system. The system could add a generic component and remove it on the next frame. It could later easily change it to enable/disable component workflow. Foreach does not work in generic systems though. What would be the preferred Job to use in this case? IJobChunk, IJobEntity or anything else?

[void girder]

Why does the profiler not show the job running on the main thread?

[solar spire]

Isn't that exactly what it's showing?

[void girder]

Usually I would be able to see the job name that's running

[solar spire]

If you call Complete the job will force itself to finish on the thread you call it from

[void girder]

Hmm actually yeah nvm then

[solemn hollow]

prefered should be IJobEntity. But im not sure how well it works with generics (if at all). following in order IJobEntityBatch, IJobChunk,IJobFor

[pulsar jay]

Thx. Its the first time I use IJobEntity but the write once and reuse in multiple systems approach looks promising

[pliant pike]

interesting I've been wondering how to do something like that for a while 🤔

[pulsar jay]

Anybody has an example on using an ECB in a IJobForEntity?

[solemn hollow]

Havent tried yet but you should be able to just pass it into the job like you would in for example an IJobChunk

[pulsar jay]

Any example for that? Havent used that either 😅

[solemn hollow]

    {
        public EntityCommandBuffer ecb;

        public void Execute(Entity entity)
        {
            
            ecb.RemoveComponent<MyComp>(entity);
            
        }
    }```

[pulsar jay]

Ok thats simpler than I thought

[solemn hollow]

ofc if you use scheduleparallel u pass a parallelwriter

[pulsar jay]

I see. But that would mean deciding beforehand weather the job should be schedule or scheduleParallel later on does it?

[solemn hollow]

thats always the case

[pulsar jay]

mhh I see. Always wondered what the overhead was of using a ParallelWriter in a Schedule job

if the overhead is minimal it would make sense to use ParallelWriters in all jobs because it could be Scheduled both ways 🤔

[solemn hollow]

id assume it is low overhead but i never really looked into it.

if you really look for this kind of performance you probably shouldnt use ecb and think about a way to avoid structual changes

[pulsar jay]

yeah as mentioned earlier I am trying to build the system so I can replace adding/removing tag components with toggling component later on

[solemn hollow]

I took it more as a general question not related to your generic timer. For a timer it should be no problem anyways since you wont add 100 timers per frame to entities. For such rare events adding and removing should be just fine. Don't overengineer, especially not with features that are comming in a year in mind

[pulsar jay]

I see what you mean. The easy refactoring is really just a side effect though. The problem I actually try to solve is to have mutliple timers triggering different events on the same entity 😬

and I nearly got it working until I hit this again:
Assets\Scripts\Game\Trigger\Systems\TimerSystem.cs(37,1): error SGICE002: Seeing this error indicates a bug in the dots compiler. We'd appreciate a bug report (About->Report a Bug...). Thnx! <3 System.InvalidOperationException: Unknown typeSymbol type Microsoft.CodeAnalysis.CSharp.Symbols.PublicModel.TypeParameterSymbol 😬

[solemn hollow]

you are using IJobEntity right?

I think the codegen cant deal with generics yet

[pulsar jay]

Looks like jobs can: https://docs.unity3d.com/Packages/com.unity.entities@0.50/manual/ecs_generic_jobs.html

[solemn hollow]

yes they can. but IJobEntity is a special case

Its a Job that reduces boilerplate through codegen. the codegen effectivly creates an IJobEntityBatch for u

[pulsar jay]

Oh and the other IJobs dont use codegen?

[solemn hollow]

yes

[pulsar jay]

found this example and thought it would work with IJobEntity: https://nagachiang.github.io/unity-dots-creating-generic-systems-with-generic-jobs/#

well that sucks 😕

but I guess you are right that the codegen does not work with generics

[solemn hollow]

generics are a huge PITA with ecs :S. The problem you will face is that every type of timer you create will need an extra system running to update the type. that costs a lot mainthread performance.

[pulsar jay]

Thing is reusing code can get a pain with ECS too 😬

I got a trigger tag which triggers the targeting and the attacking systems. Now I want to separate these events. Cannot thnk of any better way then creating a second timer+tag 🤔

[solemn hollow]

So you want to wait between trigger and attack and attack to end of attack?

[rustic rain]

            _followShipJob.translations = GetComponentDataFromEntity<LocalToWorld>(true);
            _followShipJob.entities = _query.ToEntityArrayAsync(Allocator.TempJob, out var dep);
            
            Dependency = _followShipJob.Schedule(JobHandle.CombineDependencies(Dependency, dep));

I swear this makes me crazy

[solemn hollow]

what are you getting the translations for if you are not passing them into the job?

same with entities

[rustic rain]

I do pass them

into fields

[solemn hollow]

show the whole code plz

[rustic rain]

    public partial class FollowShipSystem : SystemBase
    {
        [BurstCompile]
        private partial struct FollowShipJob : IJobEntity
        {
            [ReadOnly] public ComponentDataFromEntity<LocalToWorld> translations;
            [ReadOnly] public NativeArray<Entity> entities;

            private void Execute(ref MoveTarget moveTarget, in FollowShip ship)
            {
                moveTarget.value = translations[ship.Entity].Position;
            }
        }

        private FollowShipJob _followShipJob;
        private EntityQuery _query;

        protected override void OnCreate()
        {
            _followShipJob = new FollowShipJob();
            _query = GetEntityQuery(new ComponentType[]
            {
                ComponentType.ReadOnly<LocalToWorld>(), ComponentType.ReadOnly<Selectable>(),
            });
        }

        protected override void OnUpdate()
        {
            _followShipJob.translations = GetComponentDataFromEntity<LocalToWorld>(true);
            _followShipJob.entities = _query.ToEntityArrayAsync(Allocator.TempJob, out var dep);

            Dependency = _followShipJob.Schedule(JobHandle.CombineDependencies(Dependency, dep));
        }
    }

[viral sonnet]

when scheduling the _followShipJob.entities have to be there. but hey aren't

[rustic rain]

wdym

how are they supposed to be there

[solemn hollow]

there is alot wrong here actually

[viral sonnet]

they are async, then you schedule the job but the entities are still not calculated. so that trips up job scheduling

[rustic rain]

but I combine dependencies with out dependency of async operation

[viral sonnet]

it doesn't matter if you use it as a dependency. the job scheduling fails

parameters are set in main thread and not later own

[rustic rain]

ahem

[viral sonnet]

you can solve this with IJobDefered (sorry can't remember the exact interface name)

[rustic rain]

what is out dependency of nativearray is for then?

[viral sonnet]

https://docs.unity3d.com/Packages/com.unity.jobs@0.1/api/Unity.Jobs.IJobParallelForDefer.html

[solemn hollow]

but you are not even using the entities you are getting with the async operation at all...

[viral sonnet]

this takes a nativearray that is still unknown when scheduled

[rustic rain]

I am trying to add Entities to Dependency of system

to fix error

I have posted hours ago

[pulsar jay]

Baiscally find a target -> track it -> shoot it. The track it step does not work if the other 2 happen at the exact same time

[rustic rain]

this error

[viral sonnet]

ok, guess it should work. although I've personally always used IJobParallelForDefer for exactly that problem. Anyway, maybe something else is going on. the system is tied to the query you set in OnCreated so IJobEntity is scheduled with that query anyway. (notice you have no parameters in Schedule where usually the query variable would be used) There's no reason to set the entities a second time. Something else that could be going on is that burst culls entities because it's not used in the code. Also, the entities from ToEntityArrayAsync are not disposed.

[rustic rain]

thing is, it's either internal bug or idk what it is

idk

    public partial class FollowShipSystem : SystemBase
    {
        [BurstCompile]
        private partial struct FollowShipJob : IJobEntity
        {
            [ReadOnly] public ComponentDataFromEntity<LocalToWorld> translations;

            private void Execute(Entity e, ref MoveTarget moveTarget, in FollowShip ship)
            {
                moveTarget.value = translations[ship.Entity].Position;
            }
        }

        private FollowShipJob _followShipJob;

        protected override void OnCreate() { _followShipJob = new FollowShipJob(); }

        protected override void OnUpdate()
        {
            _followShipJob.translations = GetComponentDataFromEntity<LocalToWorld>(true);
            _followShipJob.Schedule();
        }
    }

[solemn hollow]

its a dependency issue between multiple systems

[rustic rain]

I removed all clutter, tried adding Entity as argument to execute

[viral sonnet]

100% not an internal bug

[rustic rain]

then what are supposed to be the steps find out what is the issue?

[solemn hollow]

well your error tells you it has sth to do with the dependencies in TestAI

[viral sonnet]

try to set the dependency in the above code: Dependency = _followShipJob.Schedule(Dependency)

the next thing is to jobHandle.Complete and see if the error goes away. that will lead you to what's going on

at least it will pinpoint the exact problem where it happens because remember, scheduling works async so if something goes wrong, the next frame can schedule something and the dependency system starts to trip over.

[rustic rain]

I removed TestAI alltogether, error jumps to another system

[rustic rain]

I tried that

I'll try complete now

[viral sonnet]

you can also try to disable all systems and work from there.

[rustic rain]

yeah, I'll try that too

[viral sonnet]

and don't worry too much about this. the dependcy system gives us all headaches 😄

[rustic rain]

all right, Complete does fix it

[solemn hollow]

just assign Dependency in every system the error pops uo

[rustic rain]

I guess, I need special place for such systems

[solemn hollow]

up

As i said earlier thats what i do by default if im not sure about dependencies

There is some magic involved i havent grasped yet. So i am just explicit with Dependencies

[rustic rain]

kek, it also fixed by ordering last

hm

[solemn hollow]

you should avoid relying on order too much though. becomes a huge headache later on

[rustic rain]

I get it, but maybe I should just create some other group

that will be part of ECB sync point

and that will resolve all such issues

[solemn hollow]

youd want to make your syncpoints as small as possible so id not advice that. You will run into this problem alot more anyways. better handle it correctly now

But rly i dont get why its not handled automagically. maybe IJobEntity doesnt do that yet

[rustic rain]

ForEach loop gives same results

[solemn hollow]

AFAIK Entities.ForEach assigns the System Dependency by default when scheduling without params

[rustic rain]

literally same error

[solemn hollow]

hmm ok

[rustic rain]

oh well

same error points to TestAI

I look at TestAI

            Dependency = Entities
                .WithAll<SimpleAI>()
                .WithNone<MoveTarget>()
                .ForEach((Entity entity, in Translation translation) =>
                {
                    float3 pos = translation.Value;
                    int ind = Quadrant(pos.x, pos.y);

                    ind++;
                    ind = ind % 4;
                    MoveTarget target = new MoveTarget() {value = positions[ind]};
                    buffer.AddComponent(entity, target);
                })
                .Schedule(Dependency);

🙃

I really think

it's because I use Entity in component

and I should just move all similiar systems to sync point

[solemn hollow]

its perfectly fine to reference entities in components.

did u do a AddJobHandleForProducer for the Commandbuffer?

[rustic rain]

yeah

    public abstract partial class SystemTemplateWithECB<T> : SystemBase where T : EntityCommandBufferSystem
    {
        protected T bufferSystem;
        protected override void OnCreate()
        {
            base.OnCreate();
            bufferSystem = World.GetOrCreateSystem<T>();
        }
        protected override void OnUpdate()
        {
            UpdateWithBuffer(bufferSystem.CreateCommandBuffer());
            bufferSystem.AddJobHandleForProducer(Dependency);
        }
        protected abstract void UpdateWithBuffer(EntityCommandBuffer buffer);
    }

I have this little utility template

kek

saves me some code

[solemn hollow]

okay then im out of ideas. im doing the same stuff (probably everyone is doing something similiar) without problems...

[viral sonnet]

I think it should be Dependency = UpdateWithBuffer(bufferSystem.CreateCommandBuffer());

it's not set otherwise, so the AddJobHandleForProducer doesn't know what to wait for

[rustic rain]

nah

it works fine

I basically decided to solve it this way

I just drop this subgroup

near ECB sync point

and if any system uses similiar pattern, I'll just put it there

[white island]

how do I query for a certain entity within a mono behavior? Read only

And can I have entities link to other entities

Like have a component field be a pointer to another entity

So I do t have to waste time searching

[solemn hollow]

yes you can.

[solemn hollow]

i think its sth like this :
World.DefaultGameObjectInjectionWorld.EntityManager.CreateEntityQuery()

Okay am i crazy? Do ISystemStateComponents not get added when Instanciating an Entity from a Converted Prefab that has ISystemStateComponents ?????

[solemn hollow]

https://forum.unity.com/threads/systemstatecomponentdata-and-prefab.811839/

https://forum.unity.com/threads/isystemstatecomponentdata-not-added-inside-of-subscene-conversion.1268621/

Undocumented behaviour that makes no sense to me. Can someone explain the potential reasoning to have diffrent behaviour than IComponentData?

[white island]

How? Is there an EntityReference like a blob asset reference

[solemn hollow]

You can just have an Entity field inside your IComponentData. It is blittable

[white island]

Oh. Okay

[uncut rover]

System state component are ment to be tied to a specific system (to make a reactive system). The reactive system could have data outside of DOTS like a dictionary or octree or trigger something that need to be cleaned up when the entity is destroyed. If the system state component were copied in prefab instantiating or serialized in subcene the reactive system would have not have to handle it and have no chance to initialize the out of DOTS data.

[rustic rain]

ugh

how do I use system state component for reactive system?

I thought you could only use it through destroying entity

[solemn hollow]

I understand that it is not serialized in subscene but i dont see the reason why i shouldnt be able to setup a prefab with it to skip the initial setup when spawning it.

Well i would accept it anyways but then it should be documented somewhere

wasted like 2 hrs figuring it out...

[viral sonnet]

it makes sense in that way that a system that's handling added would not get triggered

[uncut rover]

Make a system
Declare a private system state component in that system
Make a query that look for entities that don't have the system state component and run a job on it that does what you want and add the system state component

[viral sonnet]

i agree, it should be documented

[solemn hollow]

yes i understand that. but if i could setup my entity without requiring to change its chunk once that would be just better

[hearty zinc]

Hi, i was wondering if it's worth using DOTS in production or not?

[solemn hollow]

I just think that there would be no harm in allowing to Instanciate with SystemSate

just gives you options

[uncut rover]

Then how do you have the system data initialized and how do you know what entities were already handled?

If you really want to do it your way just use a regular component data

[solemn hollow]

i wanna use SystemState for the cleanup logic

my usecase is a effect on an ability

the effect keeps track of effected entities in a SystemStateBuffer

the buffer is obviously empty when i spawn the effect. and it needs no further setup since it is filled at runtime when the ability hits sth

but when the effect is destroyed i need to undo the effect on all effected entities. this is where id prefer to use SystemState

Kind of like the Child buffer

[solemn hollow]

well unity would say no

[uncut rover]

Jobs and burst -> yes
Ecs -> no

[hearty zinc]

ok i see thanks

[uncut rover]

@solemn hollow I see, in that case you could add it through the ecb when you instantiate it from the prefab. But I agree that you use case is not ideally managed by system state component

[viral sonnet]

@solemn hollow what's your workflow for the projectile prefab? if you still want to make this work you can add the SystemState in the beginning

[solemn hollow]

i have a modular ability system. I spawn a whole hierarchy of abilities that activate each other to create chain reactions

[viral sonnet]

Adding the SystemState after instantiation via command buffer is not a good solution IMO

[solemn hollow]

so effects can be anywhere in that hierarchy

[viral sonnet]

but the prefab has to exist somewhere?

which could be preprocessed

[solemn hollow]

yes the prefab is authored as a gameobject

[solemn hollow]

thats the point. i cant preprocess it with systemstate

[viral sonnet]

you should be able to add it in the Convert stage of IConvertGameObjectToEntity

[solemn hollow]

no i do add it. but on instantiation it is not copied over to the Instance

[viral sonnet]

ah I see

[solemn hollow]

so im stuck between 2 not optimal solutions. if systemstate was copied to Instances i would have no problems at all

[viral sonnet]

yeah, I see the problem. I'm afraid there's no good solution I'm aware of

[solemn hollow]

i mean its fine to be restricted like that. its just so strange to not find that behaviour in the docs

[viral sonnet]

This is also new to me. I never had that use case

[solemn hollow]

i necrod a thread about it. maybe there is a little attention from unity but i doubt it

[solemn hollow]

i am using ECS from the very beginning and never stumbled upon it xD

[viral sonnet]

someone on the forum has the exact different problem 😄

[solemn hollow]

took me 2 hrs to figure it out... was totally blindsided

[solemn hollow]

?

[viral sonnet]

Poking through the ECS source code, in some of the low level stuff, I found this line:
var skip = type.IsSystemStateComponent || type.TypeIndex == m_PrefabType;
where it skips both Prefab and ISystemStateComponentData when Instantiating.

https://forum.unity.com/threads/how-to-exclude-components-from-entitymanager-instantiate.747890/

[solemn hollow]

honestly i would need that too lol

even for the same ability system:
i actually first spawn a prototype Instance for every character with abilities for all abilities he holds from the Prefab. Then at runtime if the Unit gets a buff i adjust those Prototypes accordingly. On ability use i Instanciate a Prototype

So when spawning the Instance from the Prototype it would be nice to not have to remove the Prototype Tag

[viral sonnet]

Why not use Prefab instead?

[solemn hollow]

cause the buffs affecting the ability damage for example are not added to the prefab

since that can change per unit

[viral sonnet]

about the systemState. you can utilize a batched add with a query, that way adding the systemState is really fast. as fast as it can be

[solemn hollow]

yes doing that already

Its not really a performance issue for now. its just really annoying to deal with 🙂

I am just mad i wasted hours on this

especially with the slow compile times i have right now...

[solemn hollow]

about that though. do u think it is better to do it with ECB or directly in EM

[viral sonnet]

ECB can't batch, so EM

[solemn hollow]

ECB used to batch right? now with the new AddForQuery thing it doesnt anymore

Again nothing you cant work with but now you gotta take care of where to put that syncpoint

Okay i really want to end my rant now but i gotta say it even got more complicated...
I cant batch the add command for all components i need to setup. For example i need a flag for cleanup that is defined in the prefab. So i need to manually copy over that flag from a normal ICompData to a SystemStateComponent...

[hearty zinc]

Do you know why when i installed DOTS all of these errors appeared i installed com.unity.entities , com.unity.rendering.hybrid and com.unity.dots.editor

[rustic rain]

just install latest version of hybrid renderer

[coarse turtle]

You can remove com.unity.dots.editor package too, since it's part of the main entities package

[rustic rain]

it'll upload all dependencies itself

which includes all essential of ECS

[hearty zinc]

ok

[uncut rover]

@hearty zinc don't forget you have to use unity 2020.3

[hearty zinc]

i do use 2020.3

[white island]

I want to store an object's position and rotation, but nothing else. Unity Entities has a built-in transform component, right?

[viral sonnet]

that's a weird question. transform is a monoBehaviour term. entities uses Translation, Rotation, Scale and LocalToWorld

[white island]

oh, they are separate? And what does LocalToWorld do?

[viral sonnet]

LocalToWorld is the matrix that combines Translation,Rotation and Scale

[white island]

okay

also, I got this error from using a NativeArray?

[Serializable]
    public struct InventoryComponent : IComponentData
    {
        public NativeArray<Entity> inventory; //Pointers to entities
    }

[viral sonnet]

NativeContainer inside IComponentData won't work

either use a DynamicBuffer on the entity (the easiest solution) or make an unsafe struct with the pointer to the array

[white island]

How do I use a DynamicBuffer here? Also I know beforehand that I want 32 pointers to entities.

[viral sonnet]

The docs explain it best: https://docs.unity3d.com/Packages/com.unity.entities@0.50/manual/dynamic_buffers.html

If you're comfortable with NativeContainers you can also use a NativeMultiHashMap<Entity, InventoryElement> as example. There are really a lot of ways to make this work

[white island]

Ok, using DynamicBuffer got rid of the error. So then when I initialize the component, I just preset the size to 32 for allocation?

(Also can entitiy components have constructors?)

[viral sonnet]

a struct can have methods.

DynamicBuffer has a dynamic capacity but you can set the [InternalBufferCapacity(32)]

[muted field]

why is there an unsafe list but no unsafe array

[rotund token]

a good question

that said,

    public void* ptr;
    public int length;
}```
is pretty much it 🙃

[muted field]

lol fair point

[rotund token]

it'd still be nice for the sake of methods

[muted field]

shame theres no way to see them in the inspector too

would be nice to verify my float2s populated correctly

[worldly isle]

I am currently using Entities.ForEach but I have no problem between the two

[white island]

How do I query from a Monobehaviour for an entity that has a certain value in a component field?

[viral sonnet]

Did you read the docs? queries and ForEach have filters to Include or Exclude components.

[viral sonnet]

Really no way around iterating over the entities and component and finding what you are looking for. Or if it's crucial and used often, build a hashmap for it

[white island]

So I've got this:

EntityQuery q = eManager.CreateEntityQuery(
                typeof(RefIDComponent)
            );

            NativeArray<Entity> matchedEntities = q.ToEntityArray(Unity.Collections.Allocator.Temp);

            foreach(Entity e in matchedEntities){

            }

How do I get the component from the entity?

also I am disposing it dont worry

[viral sonnet]

EntityManager.GetComponentData

[muted field]

@rotund tokengiven you're quite knowledged on this are you able to explain this in more detail:

In general, shorter jobs which can complete in a frame are much better. They are more predictable, and less likely to get in the way of each other. You should have a fixed time when you schedule a job, and a fixed time later when you call Complete on the JobHandle and access the data.

this was on the forums, but its not obvious to me why one frame jobs are "better" and more "predictable" what does that actually mean

[rotund token]

well for starters imagine a user has 4 workers
and you have 4 jobs each taking more than 1 frame

you would saturate your workers stopping anything else running

[muted field]

is there a way to force a max frame count on a job then ?

[white island]

How do I turn a regular transform into one of these?

[molten flame]

you can use float4x4.TRS()

[white island]

ah, thank you. very nice.

[white island]

What's the proper way to do an array in a component?

I ask because I'm trying to do this but it's giving me a nullreferenceexception

DynamicBuffer<Entity> outInventory = new DynamicBuffer<Entity>();
        outInventory.Capacity = 32;

[rotund token]

that's not how you create a dynamic buffer

DynamicBuffer<X> buffer = EntityManager.AddBuffer<X>(entity)

you can't create a buffer yourself

[white island]

I see, okay. Well my component needs a 32-slot array of references to other Entities. how do I do that

[rotund token]

[InternalBufferCapacity(32)]
public struct MyGiantOldEntityReferenceComponent : IBufferElement{
public Entity Value;
}

[white island]

Okay, so if I do this:

[InternalBufferCapacity(32)]
    public struct EntityBuffer : IBufferElementData
    {
        public Entity Value;
        public EntityBuffer(Entity e)
        {
            this.Value = e;
        }
    }

    [Serializable]
    public struct InventoryComponent : IComponentData
    {
        public DynamicBuffer<EntityBuffer> inventory; //Pointers to entities
    }

[rotund token]

ah no

dynamic buffer does not exist on a componet

it exists on the entity

[white island]

...oh

so, what do I do instead?

[white island]

ugh, i can't use hasmaps either.

hashmap

[rotund token]

you dont need to put it on a component

the component is on an entity

the dynamic buffer is on an entity

"they're the same thing"

[astral parrot]

Hi, me wanna ask, is there a way to "raycast all" using job system? Does the CollisionWorld.Raycastall make GC Alloc?

I tried using that with IJobEntityBatch and output the NativeList<ColliderCastHit> inside the job and it works, but I cannot compare the ID because due to two containers may not be the same (aliasing) error after I use ComponentDataFromEntity<MyComponent> and ComponentTypeHandle<MyComponent> at the same time. I was thinking using "Job inside Job" solution to compare tags for each detected collisions by RaycastAll but idk how.

[rustic rain]

you do raycast and you work with result data from raycast

if for some reason you don't want to work with result data in same job

you can cache it within some buffer

and then work with it through another job

raycast is struct

and can be dropped into dynamic buffer easily

During conversion, inside authoring mono. Do all gameobjects remain to exist?
I kind of want to setup templates of rooms through transform parenting of Unity, but avoid those empty game objects to be converted AND avoid their children getting parent components

Can I just remove all those gameobjects during authoring conversion and be done with it?

oooor do I need smth more complex?

[uncut rover]

You can add the stop convert entity authoring component to the first child of the parent game object that is converted to entity. That will prevent child to be converted and still allow you to query their monobehavior during the parent conversion.
If the aim is to not have the update transform on the whole hierarchy you can check the static box in the editor. It should add a tag component to the entity on conversion that will make the transform system ignore them.

[solemn hollow]

AFAIK stop convert Entity doesnt work with subscenes.

@rustic rain I am currently in the process to convert everything to subscenes in my game. I also thought marking everything as static has effects on the hierarchy but it didn't. you need to use the StaticOptimizeEntity component

It flattens the hierarchy as much as possible unparenting everything that is below the Entity with that StaticComponent

This gave me a huge performance boost because the LocalToParentTransformSystem wouldnt need to run anymore on 10k entities

[rustic rain]

my goal is to prevent conversion at all

I don't need those parent entities

The only use for them - have them as prefabs

So I can quickly switch between my "rooms"

since they all exist in same space

and most internal objects are literally in same places

[solemn hollow]

You probably shouldnt care about instantiating a few more empty static parents than necassary. AFAIK unity does not want you to delete Entities in the Destination world while converting. I had the same Issues but decided it is not a Problem for now to have some useless static entities.

[rustic rain]

hm

so did marking static did any changes to conversion process?

I'd want those entities to have as little components as possible then

[solemn hollow]

The hierarchy was optimized. Nothing got deleted i think. maybe someone else knows how to leverage the ConversionPipeline better. You could write a ConversionSystem that tags all "useless" Entities and then at runtime have a system Destroy all useless Entities in batch.

[rustic rain]

here's what I mean

rn I have them in separate subscenes

but I want to move them all to one

and since all those "systems" will have same things in same places, I need to be able to differentiate easily during development in editor

without an actual effect after conversion

[solemn hollow]

isnt that the perfect usecase for subscenes?

[rustic rain]

not really

I'll have other use for subscenes

for actual things that will need to be unloaded/uploaded quickly

but for those rooms

I need to be able to dynamically create them in any way I want

meanwhile subscenes are editor tool basically

[solemn hollow]

So you just want a "Room" parent instead of a subscene

[rustic rain]

System1 and System2 GO are empty, and during conversion I'd like them to be removed completely

yeah

like this

[solemn hollow]

Well then thats easy when it is defined for which objects you want the cleanup. Just add a TagComponent at conversion and destroy it in first frame. No reason to work against unities conversion guidelines then

[rustic rain]

but that still would create a lot of "child" components

on all children

[solemn hollow]

First i thought u have a really deep dynamic hierarchy

[rustic rain]

and shitload of archetypes

due to it

and there would be a lot of children

[solemn hollow]

combine it with the OptimizeStaticEntity component then it wont create children

[rustic rain]

hmm

I'm not sure, what it does

I do need children to be converted, I just want to avoid children components being created and set on all children

[solemn hollow]

yes the childentities will be there but wont be parented anymore.

[rustic rain]

oh

[solemn hollow]

just try it out

[rustic rain]

OptimizeStaticEntity so that's vanilla component?

[solemn hollow]

yes

[rustic rain]

yyyep

pog

yeah, looks like no parents component

Thanks

We really need some kind of FAQ for such little tips ngl

rn, the only way to find out about them - other users of dots

kek

I assume the only hierarchy in this tool are subscenes?

hmm

During conversion, can I somehow affect all child entities?

In particular I want to add shared component

meanwhile also avoiding adding parent/child components

[solemn hollow]

Read up on the conversion workflow. You have full access to the ConversionWorld and Destination world. In the ConversionWorld all GameObjects still exist. you can traverse the hierarchy if you want to

[rustic rain]

yeah, but for example, if I do it through authoring component:
I don't really control the order of those entities

So adding components dynamically to children GO doesn't seem viable

I should look into conversion systems

and what access they have

[solemn hollow]

yes. have a conversionsystem loop over all transforms

[rustic rain]

    public class InSystemConversionSystem : GameObjectConversionSystem
    {
        protected override void OnUpdate()
        {
            int index = 0;

            Entities.ForEach((InSystemTag tag) =>
            {
                var systemTag = new InSystemComponent() {SystemID = index};
                index++;

                foreach (Transform transform in tag.gameObject.transform)
                {
                    var entity = GetPrimaryEntity(transform.gameObject);

                    EntityManager.AddSharedComponentData(entity, systemTag);
                }
            });
        }
    }

hmm

this doesn't seem to work

debug doesn't even trigger on breakpoints

weird

[rotund token]

open your scene turn on live conversion

from memory if you want to break point

i havent checked in a while but normal conversion used to run in a separate process for performance

[rustic rain]

huh, true

welp, in break points

it doesn't find entities

var entity = GetPrimaryEntity(transform.gameObject);

this always gives Null

[rotund token]

try just transform

let me load up rider and have a quick look

[rustic rain]

huh

transform did work

weird

[rotund token]

yeah thats what i thought

[rustic rain]

but all right

[rotund token]

mapping maps to components

transform + every component that are passed for conversion

[rustic rain]

Is there a way to make a Query with shared component filter?

[rotund token]

you create a query then set your filters

[rustic rain]

no, I mean

make a query of certain sharedComponent?

[rotund token]

thats what i mean

i dont really get you otherwise ^_^'

entityQuery.SetSharedComponentFilter(new SharedCompennt {Value = ValueToFilterBy });
is this not what you mean?

[rustic rain]

ooh,yeah

that one

[solemn hollow]

you wont be able to find sharedcomponents in the conversionworld though. they do not exist yet.

[rustic rain]

nah, it's for runtime

            Entities.WithSharedComponentFilter(systemsList[add])
                .WithStructuralChanges()
                .WithNone<DisableRendering>()
                .ForEach((Entity e) => { em.AddComponentData(e, new DisableRendering()); })
                .Run();
            Entities.WithSharedComponentFilter(systemsList[remove])
                .WithStructuralChanges()
                .WithAll<DisableRendering>()
                .ForEach((Entity e) => { em.RemoveComponent<DisableRendering>(e); })
                .Run();

I'm basically redoing this mess kek

[rotund token]

hmm i get them in my conversion

                    if (!records.TryGetValue(sceneSection, out var list))
                    {
                        list = records[sceneSection] = new List<(SavableAuthoring, SavableScene)>();
                    }

                    list.Add((savable, savableScene));```

is a piece of code in my save conversion

[solemn hollow]

yes you get it in the destinationworld but not in the conversionworld

sry was unclear

[rotund token]

oh yep sure got you

[rustic rain]

hmm

is there any component list of all things that gets rendered?
I remember RenderMesh and CompanionLink

[astral parrot]

What kind of buffer can I use for this problem?

[rustic rain]

anything else?

[astral parrot]

Oh nvm

[solemn hollow]

https://docs.unity3d.com/Packages/com.unity.rendering.hybrid@0.50/manual/runtime-entity-creation.html

hmm i dont think that covers your question fully though sry

[rustic rain]

uh huh

[astral parrot]

Anyway, I have this entity that contains constraint body pair and physics joint, after the original entity has been destroyed, it become useless, so I'm trying to check whether that component has no entity inside PhysicsConstrainedBodyPair but one of the entityA or entityB is Invalid, how to check this invalid entity? or How to destroy this kind of unused entity? Is there a way I can manage this?

[karmic basin]

(with and without motion variants)
see for yourself in \Unity.Rendering.Hybrid\RenderMeshUtility.cs

@rustic rain

By the way that's v0.17, I don't DOTS nowadays

[rustic rain]

hmm

RenderBounds?

Basically, I'm looking for a component

that will be present on all rendered entities

so I can apply DisableRendering on it

and don't add it to other entities, that are unnaffected by rendering anyway

[karmic basin]

that's for culling, if the bounds aren't inside camera view, don't need to render

[rustic rain]

well yeah, I guess all rendered entities will have it

kek

expect maybe CompanionLink

which probably has it's own GO culling

[karmic basin]

ok so naive approach maybe would be to query WithAll first eight comps and WithNone DisableRendering

never really thought of it so maybe there's a better approach

[rustic rain]

I only need one component I think

[karmic basin]

or use some root wrapper

[rustic rain]

for each "rendering line"

[karmic basin]

but you said all rendered entities at first I'm confused 😛

[rustic rain]

well yeah

Doesn't mean I need literally all components mentioned in query for it

[karmic basin]

sure if you're targetting only "rendering line" entities it might best to only work on them through tags

[rustic rain]

since all entities rendered for example through GO

will have CompanionLink

[rotund token]

doesn't everything have RenderMesh for entity rendering

[rustic rain]

and I don't need any other component to know it

kinda same thing for other "lines"

with RenderMesh

I just need to know

whether there's any other similiar case

or is that it

just these 2

[rotund token]

companion link can exist on gos that aren't rendering anything

though you may still want to disable them (e.g. lights)

[rustic rain]

can anyone do sanity check pls

        private static IEnumerable<Transform> LoopTransforms(Transform parent)
        {
            foreach (Transform child in parent)
            {
                yield return child;
                foreach (Transform anotherChild in LoopTransforms(child))
                {
                    yield return anotherChild;
                }
            }
        }

That would give me literally all transforms children of parent, right?

[rotund token]

transform.GetComponentsInChildren<Transform>()

isn't that all you need?

(will return itself as well)

[rustic rain]

🤡

yep

oh well

looks like StaticOptimizeEntity breaks all children

through hierarchy

not just it's own

hmm
Is there any way to assign names without edit mode of subscene?

    public class EntityNameConversionSystem : GameObjectConversionSystem
    {
        protected override void OnUpdate()
        {
            Entities.ForEach((Transform tran) =>
            {
                var entity = GetPrimaryEntity(tran);
                DstEntityManager.SetName(entity, tran.name);
            });
        }
    }

I tried this, but no luck

[pliant pike]

yeah I've tried that before its never worked

[solemn hollow]

Never tried it after my first attempts failed but here someone made it work in 2022:
https://forum.unity.com/threads/entity-setname-with-entitycommandbuffer.723947/

maybe you cant do it in conversion for some reason

ooof i lied.
found this is my code:

        dstManager.SetName(pointEntityPrefab,"QueryPoint<" + GetComponentType +">");
#endif```

[rustic rain]

?

I don't really get it

I need to assign name during conversion

since that's the only place where I have my GO names

[rustic rain]

how do I access this component through EntityManager?

DynamicBuffer<Child> buffer = em.GetBuffer<Child>(parent);
This gives me buffer of Child, not of Entity

meanwhile I need to access, exactly Child component

[left oak]

The code Manarz posted is during conversion. DstManager is the EntityManager of the destination world of the conversion system

Also, your last two posts contradict each other a bit: do you want the Child element or not, cause that's what that buffer gives you

But the Value of Child is an Entity, I believe

[rustic rain]

oh yeah

nvm

I didn't notice

that Child contains Entity through field

kek

[rustic rain]

well, I tried either EM and DST

so far, no names

[left oak]

I would take a look at how conversion in the editor works: https://docs.unity3d.com/Packages/com.unity.entities@0.50/manual/live_conversion.html

[rustic rain]

any idea about checking whether Entity has buffer thO/

if (!em.HasComponent<Child>(parent))?

is that it?

looks like it

[left oak]

That should work, but not until after TransformSystemGroup has run

I think that's where the buffer gets added?

[rustic rain]

it's runtime thingy, no worries about conversion

kek

[white island]

Deleting entities doesn’t cause structural changes, right? Just a hole in memory that can be filled by another entity?

[left oak]

It is a structural change. It leaves a gap in terms of entity IDs that don't then reference any existing entity, but you're not gonna have gaps in your chunks after deleting entities

[white island]

great, so deleting entities will shuffle around pointers? That's not good.

[rustic rain]

        private partial struct GenerateColorsJob : IJobEntity
        {
            public CommandBuffer cmd;
            public Dictionary<int, int> _entityIndexToVersion;
            public MaterialPropertyBlock _idMaterialPropertyBlock;
            public Material _idMaterial;

            void Execute(Entity e, RenderMesh mesh, ref LocalToWorld localToWorld)
            {
                if (mesh.mesh == null)
                {
                    return;
                }

                _entityIndexToVersion[e.Index] = e.Version;
                _idMaterialPropertyBlock.SetColor(ColorPropertyID, IndexToColor(e.Index));
                cmd.DrawMesh(mesh.mesh, localToWorld.Value, _idMaterial, mesh.subMesh, 0, _idMaterialPropertyBlock);
            }
        }

Any idea why this gives me this exception?

[white island]

This function is apparently getting hit with a structural change? Why is this?

void generateInventory(IOD.GameplayElements.Inventory inv, Entity parent)
    {
        DynamicBuffer<EntityBuffer> outInventory = eManager.AddBuffer<EntityBuffer>(parent); //add buffer
        outInventory.Capacity = 32;
        print(inv);

        foreach (IOD.GameplayElements.InventoryItemInstance item in inv.inventory)
        {
            Entity newEntity = eManager.CreateEntity(ItemsArchetype); //create data
            eManager.AddComponentData(newEntity, new RefIDComponent { refID = item.refID }); //new refID
            eManager.AddComponentData(newEntity, new ItemDataComponent //populate item data
            {
                inInventory = true,
                whereStored = parent,
                owner = item.owner == "" ? nullEntity : findEntityByRefID(item.owner)
            });
            eManager.AddComponentData(newEntity, new BaseIDComponent { baseID = item.item.baseID }); //baseID
            eManager.AddComponentData(newEntity, new WorldComponent { world = SceneManager.GetActiveScene().name }); //determine current world

            outInventory.Add(new EntityBuffer(newEntity)); //Add new entity to dynamic buffer. HERE
        }
    }

is it because I add new entities during this procedure?

and thus I cannot add more to the buffer

how can I forcefully allocate a block of data to allow it though

The EntityBuffer is this:

[InternalBufferCapacity(32)]
    public struct EntityBuffer : IBufferElementData
    {
        public Entity Value;
        public EntityBuffer(Entity e)
        {
            this.Value = e;
        }
    }

And I know that there will only be 32 of them

so how can I pre-allocate 32*32 bytes to this

[viral sonnet]

eManager.AddComponentData will make a structural change. It's best to declare all the components you add in the archetype you are already using and just use setcomponent

same goes for the dynamicBuffer which you can also declare in the archetype (but that's on the parent)

[viral sonnet]

no it won't and deleting also doesn't cause structural changes as the archetype in the chunk stays the same. structural changes only occur when the archetype is changed and entities and their data have to be copied to another archetype chunk. so this means only adding and removing components will create structural changes. creating and deleting don't

deleting will leave holes in the chunk which are filled when a new entity is created with the same archetype

[viral sonnet]

the buffer is not the issue here. an internal capacity of 32 will be too big for the buffer to reside in chunk I guess. that means it will be allocated in heap, outside of chunk data, which is okay

[white island]

how do i declare them in the archetype? also i didnt know setcomponent was a thing, whoops.

[viral sonnet]

you should really read the docs: https://docs.unity3d.com/Packages/com.unity.entities@0.50/manual/index.html to learn all the concepts that are available

don't you already create an archetype for ItemsArchetype?

[white island]

yeah

[viral sonnet]

it's the same really. just use the type of the dynamicbuffer, in your case EntityBuffer

but put it on the parent. not on the ItemsArchetype 🙂

guess it's a PlayerArchetype or smth

[white island]

yeah ok to just typeof(DynamicBuffer<EntityBuffer>), //Inventory

[viral sonnet]

having a prefab for it is more convenient though

[white island]

But won't AddBuffer create a new buffer?

and thus cuase structural changes

[viral sonnet]

it does, that's why you want to define it when you are instantiating. that way a totally new chunk with the correct data types is created

otherwise you instantiate and then move data around just because you're adding after instantiating

this can all be defined with this: https://docs.unity3d.com/Packages/com.unity.entities@0.50/manual/live_conversion.html

[white island]

ok so putting typeof(DynamicBuffer<EntityBuffer>), //Inventory in the archetype will clear that space, and then AddBuffer will fill it?

[viral sonnet]

GO in subscene with monobehaviour component that define how your entity will look

you'll have to use getbuffer

it will be already added when it's defined in the archetype

[white island]

ok, got it

[viral sonnet]

make yourself comfortable with the conversion workflow. you're in a world of hurt if you don't and things will be a lot more complicated.

I have spells in a subscene which are normal GOs. They have comps like this on them so due to the conversion I already get them as entitiy.

you can make complicated code with this conversion that would be too difficult or slow at runtime

[white island]

Ok, so now I have this archetype, but the dynamicbuffer seems to be throwing an error:

NPCArchetype = eManager.CreateArchetype
        (
            typeof(RefIDComponent), //RefID
            typeof(WorldComponent), //World
            typeof(LocalToWorld), //Transform
            typeof(DynamicBuffer<EntityBuffer>), //Inventory
            typeof(NPCNavTrackerComponent), //NPC tracker
            typeof(DeadOrAliveComponent), //Dead or Alive
            typeof(NPCExtraDataComponent), //Extra NPC related data
            typeof(BaseIDComponent) //baseID
        );

And then this archetype doesn't get created which breaks everything later

[viral sonnet]

so my suggestion is that you do the same for your player entity. define it in a subscene with these IConvert comps. it makes the whole thing dynamic and you can mix and match without code changes.

typeof(DynamicBuffer<EntityBuffer>) change to typeof(EntityBuffer)

[white island]

Yes I will get more accustomed to the live conversion once I need to use it for something. The way my system works isnt compatible with subscenes at the moment, but I'm trying to use entities where I can (particularly with lots of objects/ static objects)

[white island]

wait, what? then how will it know to allocate a buffer?

[viral sonnet]

The way my system works isnt compatible with subscenes at the moment

I hardly believe that

because it's a IBufferElementData

entities understands that

if subsystems don't work you can also convert a normal GO prefab by hand with GameObjectConversionUtility.ConvertGameObjectHierarchy

[white island]

my moniobehaviours would require a lot of setup for this and id rather focus on them actually working right first haha

dang it, again with the structural changes. the inspector to find structural changes is coming soon, right?

[viral sonnet]

this has nothing to do with your MBs. think of it the same as the archetype you have just created. only that you create them in the editor and not by code

[rotund token]

is this still your code you're having issue with?

[white island]

yes, but now it looks like:

void generateInventory(IOD.GameplayElements.Inventory inv, Entity parent)
    {
        DynamicBuffer<EntityBuffer> outInventory = eManager.GetBuffer<EntityBuffer>(parent); //add buffer
        outInventory.Capacity = 32;
        print(inv);

        foreach (IOD.GameplayElements.InventoryItemInstance item in inv.inventory)
        {
            Entity newEntity = eManager.CreateEntity(ItemsArchetype); //create data
            eManager.SetComponentData(newEntity, new RefIDComponent { refID = item.refID }); //new refID
            eManager.SetComponentData(newEntity, new ItemDataComponent //populate item data
            {
                inInventory = true,
                whereStored = parent,
                owner = item.owner == "" ? nullEntity : findEntityByRefID(item.owner)
            });
            eManager.SetComponentData(newEntity, new BaseIDComponent { baseID = item.item.baseID }); //baseID
            eManager.SetComponentData(newEntity, new WorldComponent { world = SceneManager.GetActiveScene().name }); //determine current world

            outInventory.Add(new EntityBuffer(newEntity)); //Add new entity to dynamic buffer. HERE
        }
    }

the parent's component data is now using SetComponentData

[viral sonnet]

does subsequent calls to generateInventory also create structural changes? Because if the archetype doesn't exist yet, it'll count as a structural change (I think)

[rotund token]

you can't iterate a buffer and make structural changes

[white island]

all the archetypes are created on Start() so all of them should exist before this is done. Unless you mean if new entities are created

[rotund token]

foreach (IOD.GameplayElements.InventoryItemInstance item in inv.inventory)
either you need to use inv.inventory.ToNativeArray to make a copy of your buffer
or switch entitymangaer to commandbuffer

[viral sonnet]

I think this is main thread code, not a job, right?

[rotund token]

i assume so since they're using entitymanager

[white island]

right. And yes this is main thread

[rotund token]

the reason is a structural change could move the buffer you're iterating to a new chunk therefore unity invalidates them all on any change

[viral sonnet]

I'm not actually sure about this how this is counted in the structural change profiler. Just creating an archetype, more like defining doesn't create a chunk I believe. Creating an entity with that archetype does though

[white island]

yes I get that part

I have loops elsewhere creating new entities (although this is the only one that populates data using new entities). Should everything be using command buffers?

[viral sonnet]

command buffers are more for jobs. on main thread I wouldn't care too much about it at this point

[rotund token]

personally i'd do this with a command buffer (not a command buffer system, just one you create and playback after the loop)

[white island]

dang it, how do I get the current command buffer? is it in World.DefaultInjectionWhatever

sorry about all this, im hungry and frustrated haha

it says I need it from a system

but which system

er, entitycommandbuffersystem

[rotund token]

thats what im saying, ignore entitycommandbuffersystem

var ecb = new EntityCommandBuffer(Allocator.Temp);
Loop()
ecb.Playback(EntityManager);

[white island]

oh I make a new one, okay

[viral sonnet]

oh and about the capacity. the problem is that the capacity doesn't really limit the buffer. if you have 32 elements in the buffer and add one the length will be 33 and the capacity likely 64. the 32 has to be limited somewhere else in code. on that note, I don't think you would want the data in the chunk so it's best to use [InternalBufferCapacity(0)] which forces the buffer data to be allocated in heap memory.

[white island]

oh yeah I understand that part so it is limited implicitly elsewhere in the code

ok so now it looks like this:

void generateInventory(IOD.GameplayElements.Inventory inv, Entity parent)
    {
        DynamicBuffer<EntityBuffer> outInventory = eManager.GetBuffer<EntityBuffer>(parent); //add buffer
        outInventory.Capacity = 32;
        print(inv);
        EntityCommandBuffer ecb = new EntityCommandBuffer(Allocator.Temp);

        foreach (IOD.GameplayElements.InventoryItemInstance item in inv.inventory)
        {
            Entity newEntity = ecb.CreateEntity(ItemsArchetype); //create data
            ecb.SetComponent(newEntity, new RefIDComponent { refID = item.refID }); //new refID
            ecb.SetComponent(newEntity, new ItemDataComponent //populate item data
            {
                inInventory = true,
                whereStored = parent,
                owner = item.owner == "" ? nullEntity : findEntityByRefID(item.owner)
            });
            ecb.SetComponent(newEntity, new BaseIDComponent { baseID = item.item.baseID }); //baseID
            ecb.SetComponent(newEntity, new WorldComponent { world = SceneManager.GetActiveScene().name }); //determine current world

            outInventory.Add(new EntityBuffer(newEntity)); //Add new entity to dynamic buffer. HERE
        }

        ecb.Playback(eManager);
        ecb.Dispose();
    }

[viral sonnet]

outInventory.Add(new EntityBuffer(newEntity)); this gets patched with the entityCommandBuffer then, right tertle?

[rotund token]

good spot, it wont

use ecb.AppendToBuffer(parent, new EntityBuffer(newEntity));

instead

[white island]

ok

I can still set the capacity the way I did though, right

[viral sonnet]

yeah

[white island]

since that's outside of the loop

ok

HA! the errors are gone!

in the entity heirarchy is there some way to see what components are attasched to the entity

Also, thank you very much. I've neveer worked with the buffers or the command buffer before

[viral sonnet]

great! uhm, don't you see them in the inspector when clicking on the entity in the hierarchy? window->dots->hierarchy

[white island]

oh yeah. whoops. I have them occupying the same pane so I didn't see the inspector change

been a while since i worked with entities.

[viral sonnet]

hehe

[left oak]

So, the docs specifically include creating and deleting entities in their list of structural changes (https://docs.unity3d.com/Packages/com.unity.entities@0.50/manual/sync_points.html) and those functions definitely force a sync point, so why don't you consider them structural changes?

Not saying you're necessarily wrong, just trying to better understand what's going on under the hood

[viral sonnet]

I'll quickly test something so I don't say something wrong 🙂

ok, technically the unity docs are correct. creating and deleting is counted as structural change (in the profiler). although the important thing why we generally don't recommend structural changes is because of the performance issues. creating and deleting entities doesn't have performance issues. only adding and removing comps does. Honestly, it's a really bad idea that Unity puts creating and deleting into the broad term of structural changes. I can go into detail why structural changes on adding and removing comps is so problematic.

[rotund token]

public Entity CreateEntity(EntityArchetype archetype)
{
    var changes = access->BeginStructuralChanges();```

Adding a new entity can create new chunks

And creating a lot of entities is currently my biggest bottle neck on loading a save

takes ~20ms for 100k

and there's no real way around it 😦

[viral sonnet]

i think it's quite a problem when everyone is saying don't make structural changes and we actually mean, don't add/remove comps all the time

i made a pooling system for entities once XD

[rotund token]

that's fair

[viral sonnet]

the only cost was the big memcpy. figured nothing can be faster than that but it was honestly quite the pain to work with

doesn't help you for the save system of course. I hope you are keen to go down this rabbit hole and optimise it 🙂

did you calculate how much data you are allocating and how fast a memcpy would be?

also, 20ms for 100k is still really fast. even today a player has the patience to wait for that long. in case that's for some rollback system, yeah, I see the problem

[rotund token]

oh it's totally fast

and if you're saving subscene entities you don't need to pay this cost at all

[molten flame]

How do Netcode peoples deal with authoring nested ghosts?
Do you just avoid it by using spawn points?

[white island]

You can’t get GameObjects with traditional physics and entities with DOTS physics to interact at all, right.

[safe lintel]

no they dont talk to each other

[rotund token]

i handle by no not having any nested ghosts 🤣

[molten flame]

Yeah, that is becoming a more desirable solution day after day...
I've got a ship that is a ghost and a bunch of things on the ship that are also ghosts, e.g. controllable guns or computers.
They are set up as ghosts so that I can swap command target and more easily select which things I want to be replicated.
But during authoring its a massive pain cos I have to place the object manually so I can see how it looks, then replace it with a spawn point so it can spawn at runtime.
For most things this isn't too bad, but even the walls need to be done in a similar way since I don't want their colliders to bake into the ship physics body.
It's all just a mess.

[viral sonnet]

I wrote a gizmo to render meshes for spawn points

    {
        Draw(sceneView.camera);
    }``` ```private void Draw(Camera camera)
    {
        if (mesh != null && mat != null)
        {
            var matrix = Matrix4x4.TRS(transform.position, transform.rotation, transform.localScale);
            Graphics.DrawMesh(mesh, matrix, mat, gameObject.layer, camera);
        }
    }``` is the gist

[molten flame]

Ah thanks! I'll give this a go.

[muted field]

how would i store this in a native collection:
void* r = UnsafeUtility.AddressOf(ref item);

do i have to convert to int64?

[rustic rain]

Can I apply SharedComponentFilter to ForEach loop?

hmmm

and it appears I can't use non-value fields for IJobEntity

nvm anything above

Can anyone remind what is called query option to only go through components that were written on?

So it doesn't touch components that were only read only

[karmic basin]

https://docs.unity3d.com/Packages/com.unity.entities@0.50/api/Unity.Entities.EntityQuery.AddChangedVersionFilter.html#Unity_Entities_EntityQuery_AddChangedVersionFilter_Unity_Entities_ComponentType_

This one ?

[rustic rain]

yeah, I think this one

[covert lagoon]

I like DOTS

[deft ridge]

has anyone met some error by 0.50.1 p2

unity version 2020.3.34

[rustic rain]

Is there a way to get component array of certain Query?

I'm learning how to do target finding

if there's any ready material - I'll appreciate sharing it

[rustic rain]

I found out you can:

hmmm

How am I supposed to do logic separation for different rooms

Do own query for each room?

[rotund token]

Create a seperate job for each room

You can reuse the same query

[rustic rain]

yeah, just wondered

whether it makes any sense

hmm

So far I got this

        protected override void OnUpdate()
        {
            foreach (var starSystem in _starSystems)
            {
                _targetQuery.SetSharedComponentFilter(starSystem);
                var ltws = _targetQuery.ToComponentDataArray<LocalToWorld>(Allocator.TempJob);

so let's say I do some job where I determine LTW I want

how do I know, what Entity is that?

[rotund token]

Why not just go this in a job?

Anyway you can do get entity array as well to get the matching entity

The array lengths will match

[rustic rain]

how?

I am doing target finding

so for each entity that wants to find target I do search

And to do that I need to pass array of entities to choose between

so, that's it

if there's a better option - I'd be glad to know

[rotund token]

oh are you passing those values into a job?

yeah just pass the entity array in as well

usually you'd want to broadphase this though

rather than just brute force it all

[rustic rain]

what does it mean?

ah, you mean

split it into several jobs?

[rotund token]

not necessarily but usually

like roughly, physics/spatial lookups are broken into 2 phases

a broad phase (say a BVH) and then the narrow phase to find the actual collisions

the idea of the broadphase is just to narrow candidates down as efficiently as possible

avoiding having to just brute force every possibility

a fast approach that doesn't use physics is to use a quantized hash map

in fact you could set it up in a way that you could do all your rooms in a single (2 phase) job

instead of having to iterate every room

[rustic rain]

hmm

thing is, pretty much every logic will be required to be separated between rooms

logic like: target finding mostly

and considering there's going to be a lot of rooms

and a lot of entities total

separating it all into job for each rooms will kind of narrow it down

severely

on average there would be I think 10 possible targets to find

per room

[rotund token]

but say you have 100 rooms

thats 100 job schedules per query

that's not feasible performance wise

[rustic rain]

so what is better way?

[rotund token]

#archived-dots message
so im going to base this off a similar technique i used for my orca

as i mentioned 1 approach is to quantize your data into a hash map - there are plenty of other spatial queries (bvh, quatrees, etc) but for my specific use case i'm going to use this and in particular to show off something in particular

my quantize job simply looks like this

            {
                this.Keys[entityInQueryIndex] = Hash(Quantized(this.Agents[entityInQueryIndex].Position, this.QuantizeStep, this.HalfSize), this.QuantizeWidth);
                this.Values[entityInQueryIndex] = entityInQueryIndex;
            }```

these keys/values turned into a hashmap afterwards efficiently

but what you really care about is this bit
Hash(Quantized(this.Agents[entityInQueryIndex].Position, this.QuantizeStep, this.HalfSize), this.QuantizeWidth);

        private static int2 Quantized(float3 position, float step, int2 halfSize)
        {
            return new int2(math.floor((position.xz + halfSize) / step));
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        private static int Hash(int2 quantized, int width)
        {
            return quantized.x + (quantized.y * width);
        }```

what this is doing is effectively grouping all entities into a simple grid so multiple entities can share the same cell

say if step is 10 (each cell is 10x10) and width is 100 (so 10*100 = 1000x1000) area they will exist in cells between 0 and 1,000,000

now this leaves plenty of digits to add some info about the room they're in

say you have 100 rooms

simply add roomID * 10,00,000 to the value

[rustic rain]

oof, smth pretty mind blowing kek

I'll need some time to figure out what you are talking about here

xD

[rotund token]

this way you can store all your entities in a single map but can query specifically for the ones in the same room

anyway this means you can basically take

room + position.xz and find all other entities in the same cell

• neighbouring cells if you want etc

this gives you a small section of entities that are nearby to query if you want to target

anyway this was basically just the first idea that came to my head right now

and i also just had a few bottles of soju so it could be complete garbage

[rustic rain]

oh man, seperate job strat

feels bad

0.56ms

with 1 entity

xD

allthought it happens 60 times per second

so maybe I can fix it