archived-dots

[robust scaffold]

C# types are reference types. Dont use typeof?

[rustic rain]

that's why I don't really favour your style

xD

[safe lintel]

im not!

[robust scaffold]

I have to slot in the sprite renderer before light rendering but after tilemap rendering.

[rustic rain]

what is type of MainCamera?

[robust scaffold]

There's no error so it should just be a IComponent

[safe lintel]

its a struct

[robust scaffold]

What's inside the job?

[rustic rain]

oh

[robust scaffold]

Maybe try instead making this camera position job a IJobEntityBatch where the query will require ComponentType.ReadOnly<MainCamera>(), and ReadOnly<LocalToWorld>(). Then in execute write to CameraLtW[0] the only value in the batch?

[safe lintel]

thats a good idea

[robust scaffold]

Wait. GetSingletonEntity from state can not be burst compiled.

[robust scaffold]

You must first create a query in OnCreate then use the query to get singleton entity, not use the state's version.

There are todos in the entities code that indicate they want to make entity query creation burst compiled, so everything from OnCreate to OnUpdate to OnDestroy all bursted.

This new project of mine with now 4 assembly definitions is possibly the best organized project I've ever made to date

[solemn hollow]

how do i call createadditionalentity inside a conversionsystem?
Do i need to get the GameObjectConversionSystem from World?

[safe lintel]

var springEntity = CreateAdditionalEntity(gameObject);

its just a method in the conversionsystem

[solemn hollow]

oh man im so stupid sry. my conversionsystem inherited from systembase

[safe lintel]

@robust scaffold ok so still had that error pop up with using cached not state query, but using the IJEB was a good workaround.

[feral minnow]

Hi, I am a beginner in ECS and DOTS world. Everywhere I see I am being marketed with high performance. However, I see different results than in YouTube videos. For instance we have the following video by Code Monkey: https://youtu.be/ILfUuBLfzGI

However, the results that I get are:
200 FPS in an empty project;
Only one Entity;
Burst - enabled;
Script: https://pastie.io/mqbouz.cs

What am I doing wrong?

[rustic rain]

There are quite too many checks in unity ECS

200 fps in Editor = 1500 fps in Build (at least for me)

[feral minnow]

Got it 🙂 I have another question, seeing the same script that I pasted, why I don't see 3d object in a world?

[robust scaffold]

Do you have hybrid renderer?

[feral minnow]

It's a blank URP project

[robust scaffold]

Do you have the hybrid renderer package?

[feral minnow]

how to check that?

[rustic rain]

that's a package

[feral minnow]

Yup, I see it there

[robust scaffold]

https://github.com/Unity-Technologies/EntityComponentSystemSamples/tree/master/HybridURPSamples
Try going through these

[viral sonnet]

just from assembly i can't see that the value is read from stack, right? like cmp byte ptr [rsp+B4h], 0h

or does the register type tell me something?

from my understanding this would be a value read from stack.

but this one isn't vmovss xmm1, dword ptr [r13+20h]. correct?

this is why i'm asking. globalCooldown is a ref variable and a comp on the current entity

pretty huge spike here

[robust scaffold]

That seems quite extreme, just for a write operation

Is it a random access write? Because it might be a cache miss and the CPU is stalled trying to find the variable in memory

[viral sonnet]

it's a ref from this var globalCooldowns = (GlobalCooldown*)chunk.GetComponentDataPtrRO(ref GlobalCooldown_WriteHandle); so, shouldn't be random

tick is an uint and a job parameter. maybe that's the issue

i'll just test it out 😄

[robust scaffold]

Anything other than Execute should be a static function if the code is in a local to the job function.

[viral sonnet]

execute calls private void MethodNew(ArchetypeChunk chunk) - shouldn't be an issue but hm, it's weird. maybe the measurement is off.

[robust scaffold]

Me and Tertle a few days back were checking burst outputs of a method that was just private void and accessed the job properties directly vs a private static void that had the properties passed in from the parameters list. private void resulted in extra mov statements that copied values whereas the private static void did not. So always use static.

That might be the issue here

[viral sonnet]

hm, can't make it static. so next best thing, using no method at all?

[robust scaffold]

Yea

[viral sonnet]

ok, let's see 🙂

from the profiler timeline alone it didn't change anything. what it did change is that i can't see the code anymore in the profiler :/ only ExecuteInternal is visible

[robust scaffold]

Huh, no clue if the profiler is right then

[viral sonnet]

yeah, i dunno. it's a weird quirk of profilers. i have seen the same thing in vtune, VS and superluminal now

[eager pawn]

why use the entitymanager and methods like setcomponentdata in a conversionsystem instead of skipping the authoring component and just use the entitymanager within a regular system? like a spawnersystem or w/e

[robust scaffold]

Conversion system bakes in the changes to component data before you even press play. Thats why they're naming it to "Baker". It sets the starting component data at compile time, not runtime.

Well, build time. Not compile time.

[eager pawn]

thanks! :DD

https://i.imgur.com/vjUOkGB.png

are all 5 of these during build time?

[robust scaffold]

4. The last one if for Tiny (RIP) and not in regular Entities. The others are system groups that you can reference to place your conversion systems in for sorting.

It's like EarlyUpdate vs Update vs LateUpdate vs PostCameraRender methods in a monobehavior.

[robust scaffold]

ugh, get singleton results in a sync point

[rotund token]

Yes of course, you need to complete anything that could write to it

Get singleton entity doesn't

And getting the data on a job

[rustic rain]

@rotund tokensir, could you tip me what API did you use to create mega mesh for your graphics system?

[rotund token]

Do you mean my terrain?

[rustic rain]

I mean bursted creation of mesh

I realised I can make a 2d renderer like this

and I'm already half way through xD

[rotund token]

I just use the new meshdata api

https://docs.unity3d.com/2020.1/Documentation/ScriptReference/Mesh.MeshData.html

You still need to call ApplyAndDisposeWritableMeshData on main thread at some point

But you can setup all the data in jobs

If you mean my drawer for lines, I just used CommandBuffer (not entities) and built nativelists in job and passed them to this

[rustic rain]

no, I figured I try it this way

during conversion I create large RenderSprite shared comps

which contain material and large arrays of vertices, uvs and triangles

and per entity I simply add index of sprite

so during presentation foreach shared comp I grab indices for sprites

• their ltws

and then create a huge mesh

through burst job

and then I draw it all in one call

so basically meant to be: 1 atlas = 1 call

[robust scaffold]

Oh my god unity, why did they abandon 2d dots...

i am staring at the source code of physics and ughhhh, this is pain

[rotund token]

you'd be so bored if you had a full working 2d engine

what would you even work on!?

the actual game?!

[robust scaffold]

I know right, kids these days, having everything handed to them completed. back in my day, we wrote BVH builders and SAH by hand

3d privilege, smh.

[viral sonnet]

oh wow, check your struct layouts. i just optimized a 64 byte struct to 56 and gained a bunch of free performance

[rotund token]

bad ordering of fields?

[viral sonnet]

i thought rearranging fields was a thing?

[rotund token]

got to group those bools/bytes!

[rotund token]

c# default is ordered

[viral sonnet]

    {
        public SpellOwner spellOwner;               // size: 16 bytes -> 4 ints
        
        public float* snapshotSpellStats;           // size: 8 bytes
        public float* spellStatsPtr;                // size: 8 bytes
        public void* spellBlob;                     // size: 8 bytes
        
        public TargetInfo targetInfo;               // size: 12 bytes
        public byte sourceTeamId;                   // size: 1 byte
        public AttackResult forceSpellResultHit;    // size: 1 byte
        public bool fromMainEffect;                 // size: 1 byte
    }``` i have this now

best layout?

[rotund token]

yes

just make sure bytes/bools are grouped - really only thing you need to care about

[viral sonnet]

yeah got it.

do i misremember this that the compiler handles such a thing unless you have sequential or smth?

[rotund token]

sequential is c# default

if you don't do anything

[viral sonnet]

oh i see thanks

[robust scaffold]

You can also take manual control via explicit layout. But it's a pain to calculate the offsets by hand

[rotund token]

C#, Visual Basic, and C++ compilers apply the Sequential layout value to structures by default. For classes, you must apply the LayoutKind.Sequential value explicitly.

you're probably thinking about classes?

[viral sonnet]

yeah, guess so. so this is not a thing. damn 😄

[rotund token]

that said, i didnt even know you could apply layout to classes

considering it's called structlayout ^_^'

but seems like you can

Remarks
You can apply this attribute to classes or structures.

side note you should probably ask your question in burst forum not entities

much more likely to get a response from them

(that said they've been a bit less active recently though i think they were on holiday)

[robust scaffold]

Yea, they were gone for about a month and some of the employees I was stalking checked in on with twitter had a bunch of images from their vacation. All europeans and their paid vacations. Tsh.

[rotund token]

psh imagine not having paid vacations

i should take some, have like 3 months saved up =\

[viral sonnet]

yeah, i realized when i hit submit :/ i always forget burst subforum is a thing 😄

[viral sonnet]

we even get 2 additional payments in the summer and winter. so 14 times a year. but that's not everywhere, germans don't have it for example

[balmy thistle]

I think they said something something ||KornFlaks|| something something

[robust scaffold]

Basically: "2d is easy enough to make. So roll your own systems if you want 2D mechanics. We fired everyone working on 2D so good luck." That was on the post asking about a sprite renderer in hybrid at 1.0.

[balmy thistle]

URL

[robust scaffold]

https://forum.unity.com/threads/state-of-2d-packages-for-dots.1297653/

[viral sonnet]

that is a sad thread 😦

[robust scaffold]

It really is. Really really is.

[rotund token]

tldr: our priority partners do not care, only personal plebs use 2D /s

[viral sonnet]

i personally have no stake in it. my observation is just, there are a LOT of unity 2d games

can we blame richitello?

[robust scaffold]

A lot of shovelware sure. Not a lot of big budget money to unity licensed games

[rotund token]

as much as i like dots i do think this is somewhat of a valid point

it's hard to advocate internally for 2D + dots specific stuff, because it's less common for 2D games to have as serious scaling/speed issues

[rotund token]

as you say, there are a lot of unity 2d games therefore the engine is already quite capable of making them

[viral sonnet]

and that's a weird take. i think someone down the line made the point that dots mainly speeds up simulation and not just rendering

[rotund token]

you don't see many large scale blockbuster 3d games

sigh - that feeling when you are testing the build for company playtest and notice a bug that you introduced

[viral sonnet]

already out or what? hotfix dat sheeet

[robust scaffold]

Better than having someone else notice (god forbid the customer) and then all the fingers point to you.

[rotund token]

i am writing a fix atm before anyone else wakes up

[viral sonnet]

what a chad

[rotund token]

well i am kind of responsible for this build so just my job

[viral sonnet]

well, let's say i have worked with people who rather blame the alignment of the moon than fixing something asap

ok i have gone through every struct now. it's kind of embarrassing, i have made up like 0.5ms. down to 2.6ms now

[rotund token]

someone wrote a tool in like 2018 early dots

to just check every struct in your project if it's optimal

[viral sonnet]

now i hope i find some more. lol, easiest optimization i ever did

[balmy thistle]

Regarding 2D, please by all means please provide that feedback on the DOTS Roadmap. https://unity.com/roadmap/unity-platform/dots

[viral sonnet]

do you remember where to find that?

i've structured this pretty well. think i got every struct

[rotund token]

https://forum.unity.com/threads/datacomponent-size-analyzer.751616/

[viral sonnet]

would still be nice to have 🙂

very cool thanks

[rotund token]

from memory it has a bit of an issue with nested structs

i remember duplicating this a while ago and redoing it to try fix this

otherwise it has false positives

[robust scaffold]

No one reads feedback from the general public / non-paying customers.

[safe lintel]

I like viewing whats on the roadmap with that thing but I really hate the idea of typing up some sort of request that will most likely just be quickly viewed and dismissed

[robust scaffold]

Very optimistic. Thinking that your request will get viewed.

[viral sonnet]

already helped me on some structs I missed 😄 it has issues with enums that are assumed as byte but needs an int because of flags. still, very valuable tool

[rotund token]

ah yeah that was another of the issues

[safe lintel]

besides writing a request for an entire product feature like animation feels dumb 😂

hello yes, I'd like to request ecs animation please because I dunno its like a pillar of modern game design these days

[balmy thistle]

Ah, that's easy to solve. First become a paying customer

[balmy thistle]

Everything counts in large amounts as Depeche Mode taught us

[viral sonnet]

sometimes i'm just amazed what some devs are able to do. dreaming makes an animation package, this one guy writes some form of nanite in unity

[safe lintel]

oh yeah and the guy that made a visual editor for dreaming's animation package like a week later

[viral sonnet]

that's also pretty sick

i would really like to use that animation package for my actual game but i'm also targeting mobile so, not an option with compute buffers as requirement 😦

[coarse turtle]

I feel like I picked the wrong route with 2d + dots 🤔

[robust scaffold]

Or be like me. Roll your own... everything.

[coarse turtle]

Yea that's what I did lol

[robust scaffold]

300 lines just to update AABBs

[coarse turtle]

once 1.0 comes out I want to take a stab at writing an animation tree system for 2d

since I can roll onto 2022

[viral sonnet]

hope the 1.0 preview is around the corner 😄

if not, < 4 months

[coarse turtle]

yea lol

[rotund token]

unite is nov 2nd?

i hope something is shown then

[safe lintel]

There’s a unite?

[rotund token]

https://unity.com/events/unite

i think so?

Get ready for it – Unite is back and free for everyone. On November 1–2, join your fellow game developers and others from the Unity community for two full days of inspiration, learning, and connecting.

[robust scaffold]

Wow, unity purged all references to hybrid components in 0.50. I just now am looking into it and it's mentioned twice in conversion and thats it.

They did want to delete it in 1.0 but it might the only way I can convert a tilemap.

Nevermind, it's dead in 0.50

[viral sonnet]

any chance to simd this? ```[MethodImpl(MethodImplOptions.NoInlining)]
private void CalculateBuckets()
{
//Debug.Log($"CalculateBuckets with length {allocatedIndexLength} nextCap: {next->Capacity} bucketsCap: {buckets->Capacity}");

        TValue* keyArrayPtr = (TValue*) (Values + keyOffset);
        
        for (int i = 0; i < allocatedIndexLength; i++)
        {
            //var bucketIndex = GetKey(i).GetHashCode() & bucketCapacityMask;
            var bucketIndex = UnsafeUtility.As<TValue, TKey>(ref keyArrayPtr[i]).GetHashCode() & bucketCapacityMask;
            
            (*next)[i] = (*buckets)[bucketIndex];
            (*buckets)[bucketIndex] = i;
        }
    }```

seems unlikely but i want to ask

[rotund token]

not really because i+1 could use the same bucketindex as i

best you could probably do is simd the index into an intermediate array

[viral sonnet]

yeah, hm, the allocation might not be worth it though. maybe i need to try the new update allocator. from what i read it's faster because it's buffered, is that right?

[robust scaffold]

It's just a regular tempjob native array except it's "ref counted" kinda, just disposed at the end of the next frame

[rotund token]

it doesn't actually dispose

there are 64 (or 32?) pools of memory

it tracks per frame memory requests and only releases memory if recent frames aren't using as much memory

i.e. if you request 2GB in a single frame it will release it shortly but if you reliably only request say 100mb/frame consistently it'll just re-use the same blocks every frame

        /// <summary>
        /// Rewind the allocator; invalidate all allocations made from it, and potentially also free memory blocks
        /// it has allocated from the system.
        /// </summary>
        public void Rewind()
        {
            if (JobsUtility.IsExecutingJob)
                throw new InvalidOperationException("You cannot Rewind a RewindableAllocator from a Job.");
            m_handle.Rewind(); // bump the allocator handle version, invalidate all dependents
            while (m_last > m_used) // *delete* all blocks we didn't even allocate from this time around.
                m_block[m_last--].Dispose();
            while (m_used > 0) // simply *rewind* all blocks we used in this update, to avoid allocating again, every update.
                m_block[m_used--].Rewind();
            m_block[0].Rewind();
        }```

blocks not used this frame are disposed
blocks used this frame are just rewound for next frame

[viral sonnet]

thanks! yeah i have to give this a try. maybe not for this but i think i have several other places

[robust scaffold]

The absolute worst feeling is closing a subscene and getting an import error

basically gotta delete the subscene then attempt to recreate it all

[viral sonnet]

what? no, just clear the entity cache

[robust scaffold]

huh, thats what that button does

[robust scaffold]

Thinking about that chunk of code for a bit, that doesnt really work well with fixed step systems. Since fixed step typically runs slower (50hz) than the framerate locked update (60hz or 144hz). So fixed step blocks are always disposed.

[robust scaffold]

@safe lintel Seems like IJob scheduling can not be burst compiled.

[drowsy pagoda]

Is there a way in query to exclude a type of dynamic buffer? Is it enough to just .WithNone<LinkedEntityGroup>()?

[rustic rain]

yeah

[drowsy pagoda]

awesome

[rustic rain]

                vertices.AddRange(((IntPtr*)curAtlas.vertices.GetUnsafePtr() + curOffset.verts.start * Float2Size),
                    curOffset.verts.count);

can anyone tip if my math is correct?

curAtlas.vertices is a large array

of float2

I have start index and count

of part of that array I need to copy

which is in curOffset

start and count respectively

[robust scaffold]

Not (intPtr*), unless the vertex array is a set of int pointers.

[rustic rain]

I get pointer of it

[robust scaffold]

You probably want (float2*)curAtlas.vertices.GetUnsafePtr().

IntPtr is the "safe" version for a random void*

[rustic rain]

yeah, but how am I supposed to add memory offset to it?

[robust scaffold]

You can add to a pointer. Check C# docs

[rustic rain]

uuuuhm

[robust scaffold]

You might want to directly apply the add range using an ResizeUninitialized() on the array then UnsafeUtility.MemCopy into it.

[rustic rain]

@rotund token sir, could you assist me a bit?

            var vertices = new NativeList<float2>(Allocator.Temp);
            var uvs = new NativeList<float2>(Allocator.Temp);
            var triangles = new NativeList<ushort>(Allocator.Temp);

Here's what I have + meshData
Not sure how to correctly construct mesh out of that

meanwhile manual is doing some kind of weird stuff

        // Tetrahedron vertices with positions and normals.
        // 4 faces with 3 unique vertices in each -- the faces
        // don't share the vertices since normals have to be
        // different for each face.
        data.SetVertexBufferParams(12,
            new VertexAttributeDescriptor(VertexAttribute.Position),
            new VertexAttributeDescriptor(VertexAttribute.Normal, stream: 1));

[rotund token]

new VertexAttributeDescriptor(VertexAttribute.Position),
this defaults to float3 i think? going to have to give it a smaller size

VertexAttributeFormat.Float16

assume position even supports that

[rustic rain]

shoudln't it be float8?

but tbh, I do need float3

anyway

right now I have vertices, uvs, triangles

and array of offsets

which contains starts of arrays (index) and count of how much data belongs to them

each entity contains index of that array of offsets

meanwhile I also need to apply float4x4 matrix

to those values

and this is where I'm lost

[rotund token]

sorry

should be Float32, 2

[rustic rain]

ah, yes

[robust scaffold]

Here's my ultra simple circle and box sprite renderer.

Takes in a float2x3 for object to world matrix and a float4 for color. The A in color determines whether it's a box or circle.

You can probably do more fancy things with the vertex but mine's just quad

[rustic rain]

oh god

I forgot about color

oh man, this is probably some next level headache

[robust scaffold]

If this is your first dive into a SRP, you chose a wild topic.

[rustic rain]

ah, to hell with this

I'll just use default HR solution = companion links

xD

[robust scaffold]

Im pretty sure they nuked that in 0.50

[rustic rain]

nah

works

[robust scaffold]

What's it called now?

[rustic rain]

it hasn't changed

it's default HR behaviour

[robust scaffold]

But hybrid components is dead

[rustic rain]

with sprites

wdym dead?

they are just called ComponentObjects now

[robust scaffold]

ohhhhh

oh my god, maybe I can "convert" my tilemaprenderer

because I am not going to roll my own tilemap.

hrmmmm, i guess it's not as easy as just adding it as a componentobject to an entity

[robust scaffold]

Damn, guess this just doesnt work. GetComponentObject returns null regardless of what I do.

[rotund token]

it should be? or are you doing this during conversion

[rotund token]

oh yeah

[robust scaffold]

True for == null

[rotund token]

you can add it if you dont mind editing entities package

[robust scaffold]

the check is done runtime system

[robust scaffold]

oh boy, what did they lock out?

This is basic transform, the fundamental component that should be able to be added.

[rotund token]

CompanionComponentSupportedTypes

just add it 😄

[robust scaffold]

add it to?

[rotund token]

add your Tilemap to the list

and it'll work like a hybrid component

that said, good chance this breaks in 1.0

[robust scaffold]

oh, thats stupid

unity what the fuck is this

I'm gonna have to copy the entire package arn't I

[rotund token]

i personally just use a class based IComponentData then have a system that handles this life cycle mangaement for me

due to concerns about 1.0 and this feature going

[robust scaffold]

Can class based component data be baked on conversion?

Yea, im not gonna touch this for now. Tilemap conversion would be nice but not entirely necessary as I just need to pull collider vertex data from it

[rotund token]

yeah

[rustic rain]

you need to assign it first

em.AddComponentObject(e, object);

it'll add any class

Adding MonoBehaviours does weird results though

normal unityengine objects are fine though

[dire ingot]

what would be the easiest way to disable and reenable entity in runtime? What i need is to disable mesh and collider if switch is pressed and then enable them when it is pressed again.
I'm doing it with triggers and when I used EntityManager.SetEnabled(), i'm having " Entities.ForEach Lambda expression makes a structural change.", when I add WIthStructuralChanges to ForEach, unity spams errors on swith because i have dynamic buffer (i'm using statefuls from the physics example)

[rustic rain]

add Disabled tag

if you want to disable rendering use

DisableRendering

to disable physics you need to remove component of simulation index

[solemn hollow]

you can add the Disabled Tag to an entity yourself. if you do it with an EntityCommandBuffer you wont have structural changes in the lambda

[dire ingot]

Just read about that Disabled tag, trying it now

[rustic rain]

Disabled fully excludes entity from all systems

all queries*

unless specified otherwise

[heady vortex]

Can someone help me wrap my mind around the jobs system?
Basically I want to compress a bunch of data (without any heap allocations happening if possible). Would I need to create a new job for each integer/float that I want to compress and schedule them one after the other? Or how should this be structured? I already wrote all of the compression code and everything, I just have no clue how jobs is supposed to work, even after looking at examples.

[dire ingot]

it works with with command buffer, thanks. But now i have other problem, i have another trigger event connected to that trigger collider that kills the entity entering. Sometimes the switch triggers, sometimes not. I think it is due to kill happening first. I put [UpdateBefore(typeof(ThatKillSystem))] on the SwitchSystem, but it's still happening.

[rustic rain]

think of jobs as of black box

you give it input data

it does it's magic

you get back your output data

jobs (bursted and threaded ones) work only with unmanaged types

value types

for collections use Collections package

it'd be best if you initially kept your data unmanaged

so you won't need any GC during job init

[solemn hollow]

how is that supposed to help xD
you write the jobs so how is it a blackbox.

[rustic rain]

it is a black box because they are burst compiled and contain some internal code

IJobParallelFor

you don't know how it's iterated internally

you only know what happens in Execute

that's why I think of it as black box with magic

kek

(allthough you do know if you look at sources)

xD

[solemn hollow]

okay by that logic all of unity is a blackbox though. ^^

[rustic rain]

engine magic

😅

[solemn hollow]

im not sure how to answer your question.
id say you wanna pass in an array of floats and compress all of them in a single job. jobs want to operate on batches of same data.

[solemn hollow]

deleting entities inside the simulation group is a no go for me. i delay destroying them to a command buffer. you should plan out when and where stuff can be destroyed or moved in chunks (addcomponent/removecomp) and stick to those syncpoints. else you will quickly get into a dependency hell where everything needs to run in an exact order which is very hard to debug.

for example i do chunk move operations in BeginInitCommandBuffer and destroy commands are happening at EndInitCommandBuffer. this way i make sure all commands that need the entity to exist run first. that way i wont get errors telling me an entity is already destroyed when i want to remove a component from a destroyed entity.

[zenith walrus]

Hi there! Guys Is there any asset or library to draw debug lines for dots? Built-in unity system is too slow

[rotund token]

If you're willing to fork a tiny bit of cash check out aline on the asset store

It can draw from burst and is magnitudes faster

Otherwise it's not that hard to roll your own solution with basic functionality

[zenith walrus]

Thanks!

[queen dome]

Hello all, is this the channel where things about Burst should be asked?

[viral sonnet]

yes

[queen dome]

I am trying to upgrade Kinematic package to latest unity (2022) and I am having trouble with some of the burst compilation.

D:\Work\Inci_CharController\Packages\UnityKinematicaX\Runtime\Synthesizer\Synthesizer.Marker.cs(91,25): Burst error BC1063: Unsupported parameter `ref Unity.Kinematica.MotionSynthesizer` `synthesizer` in function `Unity.Kinematica.MotionSynthesizer.TraitExecuteFunc.Invoke(ref Unity.Kinematica.MotionSynthesizer.Any explicitThis, ref Unity.Kinematica.MotionSynthesizer synthesizer)`: Field `MotionSynthesizer.readDebugMemory.costRecords.m_DisposeSentinel` of type `Unity.Collections.LowLevel.Unsafe.DisposeSentinel` is not blittable. When compiling a method for use as a function pointer, only blittable types can be used in the method signature, including parameters and return type. To fix this issue, replace the non-blittable type with a blittable type. Blittable types include: void, byte, sbyte, short, ushort, int, uint, long, ulong, float, double, UIntPtr, IntPtr, pointers, and blittable structs (i.e. structs containing only blittable types). Alternatively, use a pointer - `Unity.Kinematica.MotionSynthesizer*` - instead of ref - `ref Unity.Kinematica.MotionSynthesizer` - for this struct parameter.

"Unity.Collections.LowLevel.Unsafe.DisposeSentinel" is not blittable. is the problem. It is a class that comes from the new native collections.

As it is a class it is not blittable

The code is wrapped in ENABLE_UNITY_COLLECTIONS_CHECKS defines. Does anyone know where and how I can enable unity collections checks?

Actually the problem comes from NativeList which has DisposeSentinel inside.

[solemn hollow]

Anyone got any idea why adding to an unsafe list (which is inside a NativeList)would not actually add to it?
i am adding and right after i am checking the length. length is always 0.

[pliant pike]

maybe because its a copy

I think I remember having to do something where you have to add to the list and then add the assign the whole thing back too

[solemn hollow]

dataStructure.someNativeList[index].unsafeList.Add(element);
so this creates a new unsafelist which i need to assign back to someNativeList[index]?

[pliant pike]

I guess your already creating the new unsafelist inside the nativelist

it can get kind of confusing

[solemn hollow]

thanks that pushed me on the right track. i need to first build the whole unsafelist and then assign it to the NativeList element.

[pliant pike]

yeah something like that

[viral sonnet]

try to get the unsafelist by ref. this should work 100%. cant look up code right now. it's also very likely that the unsafelist in nativelist isn't actually a pointer. so you access it by value

        internal UnsafeList<T>* m_ListData;``` ok it's a pointer.  hm, not plausible to me right now what's going wrong. length is in unsafelist which should be incremented at the right memory space. the only thing that seems weird to me is that you access the unsafelist via . and not ->

what's your actual data layout? m_ListData is internal so you must have some other form which could explain the by value access again

[robust scaffold]

Documentation is so bad sometimes

https://docs.unity3d.com/2023.1/Documentation/ScriptReference/Unity.Collections.LowLevel.Unsafe.UnsafeUtility.MemCpyStride.html
I am 100% sure this code sample is wrong.

The second destination should be source

[balmy thistle]

Oof that does look wrong

[viral sonnet]

hm, what's the actual optimization to doing it manually?

doesn't seem there's much to optimize

[robust scaffold]

Manually?

[viral sonnet]

just writing out the loop

[robust scaffold]

I assume unity pads out the lesser sized component and then runs a single memcopy over the entire array.

[viral sonnet]

whelp, can't see the actual assembly of it :/

[robust scaffold]

Yea, it's an external call so who knows.

[gusty comet]

Angry Stallman noises

[viral sonnet]

maybe it can be pulled from the symbolserver: http://symbolserver.unity3d.com/

[rotund token]

You talking about memcpystride?

It's much faster the doing a loop

[viral sonnet]

yeah

[rotund token]

It's not as fast as memcpy but it's close

[viral sonnet]

do you know if nativeslice is also faster than manual?

[rotund token]

Not sure about that, probably depends what you're doing with it

It is handy though

Took me way too long to get my head around memcpystride

Always get it wrong

[robust scaffold]

I was trying to include index into a component data array that was copied elsewhere and I thought about using it. Doesnt seem to hard to understand if my correction to the documentation is right.

[rotund token]

it's not that hard to use, i just always mix up the variables

[balmy thistle]

there are a lot of them to be sure

[viral sonnet]

i optimized a key array away in a hashmap with a manual nativeslice. wasn't useful when the key is also in the data that is indexed.

[robust scaffold]

Ya know, I'm thinking about replacing all my raw pointers from native arrays to spans.

Im wondering why unity hasnt done so already personally

[viral sonnet]

that said, i'm not the biggest fan of memcpying existing data. it never worked out in my favor

isnt span just the fancy version of stackalloc?

[eager pawn]

so i played around a bit with the different forms of conversion. first of all, i have 2 conversion systems, one of them is just declaring refs with [UpdateInGroup(typeof(GameObjectDeclareReferencedObjectsGroup))]

the other class does the DstEntityManager stuff. Also, im using the inheritance method where you extend GameObjectConversionSystem instead of using IConvertGameObjectToEntity.. i suppose a custom system is best for assigning (authoring????) variables during conversion

[robust scaffold]

Yea. It's a "safe" interface of stackalloc arrays. Like what native arrays are.

[eager pawn]

also, i would need to make a new system per gameobject?

[viral sonnet]

hm, i've only tested stackalloc in combination of memcpying a foreign native array

[robust scaffold]

The issue is of course the extra int designating length for spans.

[robust scaffold]

If you use IConvertGameObjectToEntity, yes. If you use a GameObjectConversionSystem, no.

[eager pawn]

good!

[robust scaffold]

Ive been reading through the physics source and they use stackalloc to create arrays inside job code instead of creating a native array

[eager pawn]

class BerryConversionSystem : GameObjectConversionSystem
{
    protected override void OnUpdate()
    {
        Entities.ForEach((PrefabReference prefabReference) =>
        {
            //DeclareReferencedPrefab(prefabReference.PrefabGameObject);
            Entity prefab = GetPrimaryEntity(prefabReference.PrefabGameObject);

            Debug.Log(prefab);
            //DstEntityManager.Instantiate(prefab);

            DstEntityManager.AddComponentData(prefab, new Berry {
                Id = 1
            });
        });
    }
}

[UpdateInGroup(typeof(GameObjectDeclareReferencedObjectsGroup))]
class PrefabConverterDeclare : GameObjectConversionSystem
{
    protected override void OnUpdate()
    {
        Entities.ForEach((PrefabReference prefabReference) =>
        {
            DeclareReferencedPrefab(prefabReference.PrefabGameObject);
        });
    }
}

it's a bit messy still

[robust scaffold]

You dont need the PrefabConverterDeclare. Unity automatically declares reference prefabs for the target component.

Wait, the prefab game object

[viral sonnet]

makes sense, it's very fast and local memory after all. with native array, i think, you don't know where it actually ends up

[robust scaffold]

yea, that's how ya do it.

[robust scaffold]

Yea, so much raw bleeding pointers everywhere though.

[eager pawn]

thanks for all your responses and help kornflaks (:

[rotund token]

no it doesn't thats why you have the whole IDeclareReferencedPrefabs interface

[viral sonnet]

i actually have no idea what you're trying to do with this conversion

[eager pawn]

u really helped

[robust scaffold]

As in, it automatically DeclareReferencedPrefab(prefabReference). Not DeclareReferencedPrefab(prefabReference.PrefabGameObject); which is needed.

[rotund token]

oh yep ok

[robust scaffold]

Probably their first conversion. Get something converted successfully and then go from there.

[eager pawn]

i just try to create a berry entity with a Id field set to 1

[viral sonnet]

i'd start with a IConvertGameObjectToEntity conversion first

[eager pawn]

i still have that code too

i did both versions actually

[viral sonnet]

are both not working?

[eager pawn]

i just thought custom conversion systems would be better if i wanted to assign variables during conversion, but perhaps both work

[viral sonnet]

i have some pretty complex authoring setups and i never needed GameObjectConversionSystem

[robust scaffold]

I use GOCS exclusively. I dont want to slap on a ICGOTE on every GO i'm converting. One GOCS is good for all the lights i'm rendering for example.

I cant wait for baker so we dont need to use all these acronyms

[viral sonnet]

what's the difference, both work on 1 comp, right?

the power of a GameObjectConversionSystem is that you can run more complex queries and over multiple comps

[eager pawn]

yeah idrk how to make a GOCS for many components, haven't gotten to that part yet

right now it assumes a Berry

[robust scaffold]

GOCS works on all components using an Entity.ForEach() while ICGOTE works on the GO that it's attached to.

[eager pawn]

i just filter with entities.foreach?

[robust scaffold]

Just add more Entity.ForEach() for every component you're converting.

[eager pawn]

kk

easy

[robust scaffold]

It's a different .ForEach than the one in SystemBase. It's the ancient lambda version

doesnt have filtering, cant do more than 1 component.

[viral sonnet]

i worded that wrong, you are just using one light comp is what i mean

[robust scaffold]

Yea. It also works on default components like transform which I run through a GOCS as well.

[viral sonnet]

you can get the MB comps in a IConv too 🙂

[robust scaffold]

Yea, but then you have to link them in the inspector. Or use GetComponent<>() which might result in null errors.

[balmy thistle]

these acronyms are getting out of hand

[robust scaffold]

IJFEWI, IJPFD, NMHMP

[balmy thistle]

ikr

[viral sonnet]

thrown a requirecomp tag on it. that said, i've moved to completely seperate full authoring comps now. adding all these little comps was getting stupid

[robust scaffold]

The tags are annoying. I might make a component with a flag enum to toggle on the flags added during conversion

[viral sonnet]

2 tag comps, ewww 😄

[robust scaffold]

I got an entire GO dedicated to system enable tags and singleton data

[gusty comet]

How do I accept DOTS as my personal lord an savior?

[robust scaffold]

One: Forget how to code. Completely. Rip it all out by the roots.

[gusty comet]

Become one with nothing, got it.

[robust scaffold]

Two: Code all 9 of these samples by hand: https://github.com/Unity-Technologies/EntityComponentSystemSamples/tree/master/ECSSamples/Assets/HelloCube
Play around with the result once you get each sample working. See what happens if you add another component, maybe keyboard inputs to control rotation speed, maybe an authoring component.

[gusty comet]

Let´s go

[robust scaffold]

Three: Get an IDE that lets you "Go to declaration" of a method. DOTS is fully open source but with shit documentation. You'll need to read the actual source to figure out what's going on.

[gusty comet]

Reverse engineering is my first second and third name now.

[robust scaffold]

Four: You know have accepted DOTS into your life. Go out and preach the glory that is ECS. Burn the OOS coders at the stake.

[rotund token]

the actual code is pretty well documented (doubling your point)

[robust scaffold]

The code has quite a bit of comments at the surface to mid level. Deep in it gets a little sparse but with the previous comments, it can be easily understood.

[devout prairie]

I think it's safe to say that, all of the things that make OOP and managed code so easy and quick to work with ( and are also their performance achillies heel ), must be thrown out and forgotten about

although, some stuff is in some ways quicker and easier in DoD/ECS which is nice in it's way

[rotund token]

at work, we're at a point where dots holdouts are finally realizing how easy it is to add new content to an advanced project

compared to oop

[gusty comet]

"-uses ScheduleParallel to schedule the lambda to run on multiple worker threads..." Sure?

[robust scaffold]

Yea, DOTS is a lot more modular.

[robust scaffold]

Schedules an Execute() call for each thread, if possible. Try playing around with an IJob for an intro to job scheduling and burst

[gusty comet]

Roger that.

[devout prairie]

i guess technical debt is less of a problem with ECS arguably

[robust scaffold]

Yea, since everything is flattened and independent of each other (largely), you can rip entire ECS sections out with little impact. Well, other than now that section is gone.

[devout prairie]

there's definitely costs associated with learning ECS and changing over though

[robust scaffold]

The initial curve is hard yea. Cant really teach the 10yo kiddies how to think data oriented. If they only recently evolved object persistence.

[devout prairie]

and i'd say 100% it's easier to rapidly prototype in for example classic unity oop

[rotund token]

i actually wonder about that

[devout prairie]

compared to doing like for like in DOTS

[rotund token]

i have a theory if you never learned OOP you'd have a lot easier of a time

[balmy thistle]

tough to tell, given it's the dominant model

[robust scaffold]

Learning ECS/DOTS as a 22yo back then? Yea, easy. Now if I was learning it at 12? I could barely count my fingers... kinda. I think. Cant really remember what I was doing back then other than running around.

[rotund token]

i can remember! i was making choose your own adventure games in vb6

[robust scaffold]

You can show a kid that an apple has a property color of red. But can you really imprint upon them that while this apple has a color red, another apple has a color green and that both apples can be represented by a single entity indicating their unique identifier with a common component containing the property color.

[gusty comet]

(input-parameters) => expression It makes sense but how?

[devout prairie]

i think that definitely yeah without a problem, the only factor being if they're interested in learning that

[robust scaffold]

That too. Kids are on natural crack most of the time.

[devout prairie]

also these days they're literally on the crack that is social media, which is really consuming a lot of their energy i feel

insta/tiktok/youtube/etc, it's almost like a drug addiction

[robust scaffold]

God i am so glad to have been born before smartphones really infiltrated the classroom of grade school.

[rotund token]

Didn't get my first phone to year 10. I was born right on the transition

[devout prairie]

it's definitely interesting that, there are two or three generations right now that were born around that time where, they sortof have one foot in the old world and one in the new

pretty significant in a lot of ways because the 'new' world is so insanely pervasive, and insidious in a lot of ways

[rotund token]

I would have been a really early Facebook user but these days don't use anything (except if you count YouTube I guess)

They say parents killed Facebook, I agree

[safe lintel]

navigating the world without a phone were good times

bus maps were my bane

[robust scaffold]

Bus maps these days are also pretty bad. If you use the official app or whatever they provide.

Google maps is a god send on that front

[rotund token]

Does anyone just not use Google maps for this?

I do use the tram app just because it has real time tracking so I can see if it's late

And that data isn't in Google yet for us

Though buses recently were added

[gusty comet]

Only way I get anything done is to lock the phone for days.

[robust scaffold]

I still have the ancient continental US atlas in the back seat of my car.

I hate tictok and short form video. Glad I never get distracted on those at least.

[rotund token]

The only reason up upgraded from my s8 was because i ran out of battery trying to get home and it had my ticket on it

[robust scaffold]

My S8's running strong. Probably another year or two before i upgrade. Dont use it much except for reading fanfiction...

[devout prairie]

haha s8 here too

[rotund token]

I really don't use my phone except to chat in here on public transport

[devout prairie]

camera is pretty decent tbf

[rotund token]

Which I'm doing atm

[robust scaffold]

Battery life aint good anymore but I bought a 15 foot USB-C cable and it never leaves the charger.

[devout prairie]

definitely i'd say there's good and bad sides to the tech we now have, definitely a ton of benefits to it, and a lot of bad stuff also

[rotund token]

We're all evil mobile developers feeding on addiction right

[safe lintel]

ill be honest, I loved my note2 & 5 but after switching to apple(because I constantly had issues where text messages only went through half the time to other iphones), the experience is way better

[devout prairie]

a lot of kids are way more tech savvy whether through progressing to modding games or even writing games, hacking, etc etc

[gusty comet]

Imagine having money to buy an Iphone.

[robust scaffold]

mobile devs are literally the antichrist.

[rotund token]

Richy Rich over here guys

Can you fund my super awesome unique mmorpg game

[safe lintel]

my monocle just popped out

[robust scaffold]

mobile has been the pioneers for the worst gaming industry practices. Microtransactions, Macrotransactions, pay to wait, whale hunting, etc

[rotund token]

Pay to win

Yet people eat it up =(

[safe lintel]

also the whole upgrade phone addiction/cycle

[robust scaffold]

I get upgrading a computer but damn, my little handsized metal brick cost nearly as much as my 17" development laptop.

[rotund token]

I feel like that's wearing off a little?

There's been very little to be excited about in recent phone generations

New camera is about all that is advertised

The only thing interesting recently are the folds

[robust scaffold]

I go 3 maybe 4 years before upgrading laptops because there has been noticable and significant advancements in computing power. Phones? Uhhh, more cameras.

[rotund token]

Which I would actually consider getting if I could justify the price

Love they brought back flip phones

[robust scaffold]

Cant bring a flip/fold into the shower. Instant no buy for me.

[rotund token]

Well haven't owned a laptop since uni

Loved it, hybrid was great for note taking

[robust scaffold]

cries in eternal purgatory grad school

[rotund token]

I went back and spent 30k to do a masters for no reason

Just boredom

[robust scaffold]

At least I'm funded with only undergrad loans. Poor souls are stuck here self funded.

[rotund token]

Yeah not greatest idea

Oh we have government loans tied to price index

And undergrad is 50% covered

[robust scaffold]

Oh yea, my loans are not linked to interest which is nice. Recent inflation has been steadily decreasing my loans without having to even pay it.

[devout prairie]

hah

[rotund token]

Well that's nice

During covid it was like 0.2%,last year like 3.7% 💩

[devout prairie]

i guess salary has to increase with inflation for that to work though right

so any word on entities 1.0 being still on track for release

[robust scaffold]

0 info on my side but random guess is probably 3 or 4 months out. The Aspect API seems really raw.

[rotund token]

I believe so, last I heard they were actually ahead of schedule

[robust scaffold]

Like SystemAPI.Query<>()? Come on.

[devout prairie]

i'm guessing conversion workflow will take the biggest hit for people not using subscenes etc possibly.. i noticed it does say in the docs that for example GameObjectConversionUtility for converting on the fly will be dropped

[gusty comet]

Channel is surprisingly based in economics.

[rotund token]

SystemCodeGenJobApi.QueryEntitiesWithComponents<>

Is what you're looking for right

[rotund token]

Netcode devs recently said this game been removed

But still under discussion

[robust scaffold]

Completely not. Unity will never lower themselves and shorten their class names.
SystemCodeGenerationForEachJobApplicationProgrammingInterface.QueryEntitiesWithComponents<>()

[devout prairie]

i think possibly also IConvertGameObjectToEntity for mono's might be dropped, not sure though

conversion is still for me a bit messy and unsure

[robust scaffold]

Everything merged under a single Baker. Does seem like it in the training. I see no examples using other conversion methods other than a single baker.

[devout prairie]

docs are a bit sparse on it also, the examples leave me thinking 'but what about this or that etc'

loading up samples and trawling through how they've did it is kinda painful also

[robust scaffold]

Once you get it nailed down, it doesnt seem that difficult or confusing.

[devout prairie]

so yeah i think a single unified approach with maybe some alternatives for exceptions/caveats will be useful

[devout prairie]

yeah i think conversion system seems to be the best way forward

referenced prefabs is still a little bit of a grey area ( although i do understand and have a workflow for it )

and also for example conversion of stuff like joints and things that aren't created or initialized until later in the conversion pipeline

so potentially you might need different conversion systems running at different points in the pipeline to handle this stuff

[robust scaffold]

Yea. I have no clue how to link together hybrid game objects properly. Tilemaps for example. Tried last night but then ran into the issue where I'll need to modify the entities package to allow for conversion of tilemap renderer and such. So I have a temporary solution of authoring the data I need at runtime OnCreate which is not ideal.

[devout prairie]

they've said they intend to lean towards supporting a hybrid workflow so i'm guessing there will be a few things that will basically just have to be hybrid, until they build in support for them

i kinda wish they'd said 'screw hybrid' and went/focused on full tilt dots tbh 😛

[robust scaffold]

Converting everything done currently for GOs to DOTS will probably take years

Even more so than what it has taken so far to even make DOTS (development hell)

[devout prairie]

yeah i guess.. tbh i think they've done so well with entities/burst/etc, it almost feels like it would be harder and more messy to support a hybrid approach

but i guess in many cases it's easier to just, create a bridge for hybrid stuff, and that's that

[gusty comet]

Is there not always the option to migrate to Unreals ECS or what ever they call it?

[robust scaffold]

Unreal's ECS is extremely barebones and new.

Despite everything, the years in development hell for unity DOTS have really solidified the ECS structure and style of the code.

[devout prairie]

kinda hilarious when you see like, the guy that created flecs for example, just doing it alone, in less time

you wonder what takes unity so long to do similar things

[robust scaffold]

Too many cooks in the kitchen.

[devout prairie]

yeah

[robust scaffold]

9 mothers cant produce a baby in 1 month. Just 9 babies. Is DOTS the equivalent of 9 babies? Maybe, there's definitely some loss in efficiency with the scale unity has been chucking at this project now.

What they've done with Burst and making C# code equivalent to C++ is extraordinary though.

[devout prairie]

stuff like jobs and burst, are a revelation in what they offer and can do for the platform, ecs also, but you do wonder, why take so long

[robust scaffold]

Building from that foundation though is where Unity has definitely tripped and tumbled down the stairs a bit.

[devout prairie]

probably the requirement to integrate everything with the existing api's/enginecode, and also the UI has been a big part of that

[robust scaffold]

UI hasnt been the bottleneck though. They had this interface solidified within weeks following 0.17 release if you read between the lines back before they went complete radio silence.

[devout prairie]

so i guess in a way bureaucracy just as a function of being a large organization has held it back

i wonder how many of the huge leaps have been rapid advances by a few talented individuals vs many drawn out periods of small incremental changes/updates by the wider organization

[robust scaffold]

That's typically why research labs are structured very hierarchically. One or two lead researchers driving a group forward, determining what's the goals, what's the deliverables, what's the data required, and the lab scientist do the data gathering, the confirmation, a bit of the analysis.

Issue is with coding, it's very hands on. Lead researchers dont typically actually do the data gathering manually whereas coding, yea one brilliant coder with a vision can singlehandedly do the entire work.

[viral sonnet]

one has only to look at the code of cinemachine. working with lots of people also means the code can be monolithic and full of weird decisions. then this whole thing about codegen, Entities.ForEach lambda, etc... it's a lot of overhead and pretty complicated to solve it all

[gusty comet]

Economics is a science, a soft science like sociology but science none the less. The term for this is diseconomies of scale if you want to sound like a prick.

[robust scaffold]

And coding is as much a creative art than it is procedural science. You can have collaborative artwork but it together very rarely looks as good or superior to one great artist's work.

[devout prairie]

yeah interesting analogy, like a dozen painters working on a single work of art as opposed to a single artist

anybody know how many devs are actually assigned to any of the dots systems

[viral sonnet]

talk was around 50 are in the dots team

[robust scaffold]

And like artwork, 10 painters can whitewash a wall a lot faster than one but even DaVinci didnt finish the Last Supper.

[devout prairie]

i wonder if that includes like burst for example, which you could maybe say is mostly done except for incremental upgrades

does it include stuff like Animation

i guess everything under the namespaces

[robust scaffold]

burst seems like a very small specialized team. I've only seen 3 unique unity employee names responding to questions and bugs on the forums relating purely to burst issues.

[gusty comet]

I can imagine there is a 5 to 1 ratio of social and less social people on that team. Surely a company as large as Unity Technologies can not have a 5 man tea, running this show? (!hend Selp ran out of Lager at 2 am! How can I now forget how to program?)

[robust scaffold]

Ya know, I'm starting like like stackalloc. It allows for some really nice burst optimizations in loops:

Makes reading and understanding what's going on a lot harder though

[gusty comet]

Some day I will get the meaning of this.

[robust scaffold]

Just vectorization and entire array actions

[rotund token]

Stackalloc is great if you have small known or calculatable max values

You can speed it up a tiny bit more turning off its memclear on allocation as well

If you really want to optimise

https://docs.unity3d.com/Packages/com.unity.burst@1.7/manual/docs/OptimizationGuidelines.html#skiplocalsinit-attribute

You do have a limited stack size though

[robust scaffold]

true, forgot about that. So it doesnt skip twice.

[robust scaffold]

BinMinusOne is 7.

[rotund token]

Yeah that's perfect here

[robust scaffold]

I got plenty of space, stackalloc is only at uhhh, 40ish

[rotund token]

I've just seen some people use it on like entity count or something silly

[robust scaffold]

.seh_stackalloc 56

[viral sonnet]

what? not even on the chunk entity count but whole query?

[rotund token]

yeah passed in a query.ToEntiyArrayAsync thingy (wiht some data)

and were doing iterations of them

[timber ivy]

so if i have one scene with 1k subscenes is that gonna be a problem?

[rotund token]

probably not?

[robust scaffold]

Ya got me checking my code. Node count is possibly = num entities so i gotta add a conditional to go to heap if too big.

[rotund token]

yeah ive seen this work before - it's a nice conditional optimization

[robust scaffold]

Subscenes are just a conversion tool. It doesnt matter how many you have.

[timber ivy]

So will it make loading the scene take longer if there are a ton of subscenes than if everything was just in the scene im loading?

[rotund token]

if you open every subscene at once its probably going to take a while

[robust scaffold]

Ehhhh, sorta.

[rotund token]

but subscenes are designed to handle large open worlds with a lot of them, and just streaming them in as needed

[timber ivy]

alright

[robust scaffold]

Runtime loading depends on scene streaming loading speed. Aka reading from the scene byte compressed file.

[timber ivy]

thats what I am using them for

[robust scaffold]

If you have a 1000 of identical scenes, the speed will be very quick as it just needs to load 1 scene and and then multiply that 1000 times.

If you have 1000 different scenes loading at once, that's gonna take a while.

it'll pop in one after another since scene loading is asynchronous. So the game will slowly pop in unless you write a loading scene that waits for all scenes to completely load in.

[timber ivy]

my plan is to split the world in 100x100 chunks each 100x100 area of the map will get its own subscene

each area of the map has unique vehilces and pedestrian models

[rotund token]

if you're curious about real world situation

v-rising has 872 subscenes

that's how they split their world up

[robust scaffold]

Wow, v rising is dots: https://blog.stunlock.com/v-rising-dev-update-4-v-rising-engine-and-cutting-edge-technology/

[timber ivy]

would I be better off just leaving the vehicles/peds in bundles or would each ped/vehiclce having its own subscene that I load when I need be a bad idea?

[rotund token]

yes

first published dots game i've seen use subscenes

all the others were started before they were really a thing

[robust scaffold]

Subscenes are the DOTS prefab. Each vehicle should be in it's own subscene. You can nest subscenes like nested prefabs.

if a vehicle is just 1 entity, ya dont need to make it a subscene. If it's multiple entities working together, one subscene should group them together and you add that as the vehicle.

I think with 1.0, subscene UI is getting a brush up. The UI preview presentation on youtube was really focused on subscenes and their interactions / conversions.

Right now it's a little uh barren. But it functions.

[devout prairie]

what approach do you guys have to enemy in range / detection.. can never decide whether do use a custom system that stores all current positions and loops over each doing a distance check, or just use large colliders with trigger events

[timber ivy]

Are there any other options for loading shit at runtime then? because right now it takes about 3 seconds to open a bundle load what I need from it and instantiate it. and I am trying to speed that up a bit

[robust scaffold]

Ohhhh boy. Join me in handcrafting a BVH. Or just use Unity Physics and their superior implementation.

[timber ivy]

why not a spatial hash?

[robust scaffold]

Loading of subscenes is not framerate bound. Try to do something while it's loading.

otherwise, pre-load it beforehand or get a SSD.

[devout prairie]

yeah i mean i'm thinking physics already has all of that optimized in broadphase right, just curious how others are doing it though

[robust scaffold]

Reading through the physics system source, it's been purpose built for that. Their broadspace BVH construction is magic. Just turn off the kinematics if you dont want physics to be driving your movements.

[timber ivy]

I have an m2 the async calls are just really delayed. It doesn't stall my fps just takes ages for them to load. and there isn't really anything to wait on. If I decided to update the vehicle pool so new vehicles are added to it it just takes forever to do in the background.

[rotund token]

unity's bvh is pretty re-usable as well

[robust scaffold]

It's just 3D. And I dont want the extra memory of more useless floats.

[timber ivy]

spatial hash built around Rect works best for this imo

[rotund token]

i was about to say my spatial hash is something like 4x faster for finding nearest neighbours for my orca system

[viral sonnet]

sphere cast is fastest. triggers are really bad performance wise

[rotund token]

but it's very specialized and can do a lot less than the bvh

but having a collection of nearest targets is very useful

[devout prairie]

i'm already driving the units via forces so i'm currently just adding an additional trigger collider and looking to capture it in my stateful event code, so yeah i'll probs do that

[timber ivy]

sphere cast wont be faster than non physic based solutions.

[rotund token]

a lot of systems ends up using the same type of data

[devout prairie]

ah really

[rotund token]

whether for targeting, local avoidance etc

[devout prairie]

tbh the stateful event system i've lifted from the physics samples is hella slow when there's a lot of collisions.. uses buffers on the entities etc

[viral sonnet]

i didn't say it's the fastest. it's the fastest when using dots physics though

eh, you get the meaning. i did say that haha 😄

[rotund token]

these trigger/collision events fire back single threaded

and you have to basically sort the data to do any parallel work on it

triggers are best left for rare events imo - entering specific areas etc

if you're querying every frame find something else

[devout prairie]

what then would you say is the optimal approach?

[robust scaffold]

BVH is design for linear raycasts. It's what makes realtime raytraced lighting work (DXR etc). Other hierarchies work better for other situations.

If you need a raycast, and you need 4million of them per frame, BVH all the way.

[timber ivy]

are the entities you're querying for moving?

[rotund token]

i have not found anything faster than a spatial hashmap for nearest neighbours - if you find something let me know

[devout prairie]

yeah

[timber ivy]

then use a spatial hash

if they are stationary

use a quadtree

[devout prairie]

any good implementations you can point to?

to save remaking the wheel

[robust scaffold]

https://github.com/adam-arthur/spatial-hashmap here's one I googled up real quick.

[timber ivy]

https://pastebin.com/zWpSSX0W

I haven't tested this

[devout prairie]

i did actually write one for this for my previous dots project, but always looking for good recommendations

[timber ivy]

but this is how I do it

i like to use rect.overlaps

that way you dont have to add the whole cells collection when you query it

[viral sonnet]

the problem i see in 3d space. nearest neighbour is only half of what you'd need. typically you also need a raycast.

[devout prairie]

i think yeah you could call spacial hash a broadphase and then you have a narrower list of entities to poll for raycast

[viral sonnet]

i haven't figured out to make dots physics work selectively. all colliders are built

[coarse turtle]

yea this is what i do for 2d

[viral sonnet]

so you have the bvh and spatial hash to build. not really optimal

[timber ivy]

works fine for 3d for most cases too unless your game has a lot of vertical building going on or something

[robust scaffold]

Collision flags?

[devout prairie]

i think Latios implements a way to query selectively, but i haven't actually tried latios just read the docs

[rotund token]

this is how long it takes to build my spatial map every frame for 200,000 entities

[viral sonnet]

a pillar is enough or some enemy inside a building

[rotund token]

the single job is because i found batch adding to the hashmap to be significantly faster than doing it in parallel and only uses 1 thread

[timber ivy]

why you rebuilding it every frame?

[devout prairie]

i think the problem is, when you're polling collisions, you can't poll say the unit/ground pairs you have to poll all collisions

[rotund token]

because things move every frame and it's faster than determining this and rebuilding parts

this is for my orca implementation (actor avoidance) so there are no static objects

[viral sonnet]

can you implement some change filter?

[timber ivy]

You got your spatial hash posted anywhere curious how its designed. I just use a dictionary with cell as a key and a list of items as value and remove/readd the item when the item moves

[rotund token]

let me grab it

very simple actually

[timber ivy]

awesome thanks

[rotund token]

i havent looked at it in a year so there's a 50% chance i notice something straight away i want to improve 😄

[timber ivy]

haha

thats usually how it works

[rotund token]

        private struct QuantizeJob : IJobFor
        {
            [ReadOnly]
            public NativeArray<ORCAAgentState> Agents;

            [WriteOnly]
            public NativeArray<int> Keys;

            [WriteOnly]
            public NativeArray<int> Values;

            public float QuantizeStep;
            public int QuantizeWidth;
            public int2 HalfSize;

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

```        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        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);
        }```

that's the quantize job you can see in the above profile

the first bit determining their cells

the populate job just looks like this

        private struct PopulateSpatialHashMap : IJob
        {
            [ReadOnly]
            public NativeArray<int> Keys;

            [ReadOnly]
            public NativeArray<int> Values;

            public NativeParallelMultiHashMap<int, int> SpatialHashMap;

            public void Execute()
            {
                this.SpatialHashMap.ClearAndAddBatch(this.Keys, this.Values);
            }
        }```

just my batch add operation for a hashmap

[timber ivy]

bruh I didn't even know this was a thing

NativeParallelMultiHashMap

[rotund token]

o_O

[timber ivy]

I just started using dots like 3 days ago

[rotund token]

oh fair enough!

[timber ivy]

i've used a bit in the past

but not a whole lot

[rotund token]

yeah its /kind of/ a replacement for dictionary<T, List<TV>>

[timber ivy]

can you access its indexer?

[rotund token]

you can get an iterator from a key

[timber ivy]

oh cool

[viral sonnet]

guess most of the populate comes from the memcpy. maybe could be sped up with my ArrayHashMap 🙂

[timber ivy]

How are you querying it?

[rotund token]

yeah i probably could

i think there was a reason i didn't do that though

but i can't recall

should probably investigate it

well whenever i get around to actually integrating this system in my game

i'll revisit that

[timber ivy]

is it possible to create a subscene programmatically?

[rotund token]

there's nothing special about a subscene

it's just a regular scene

and you can create a regular scene programmatically

just create regular scene and assign it to a gameobject with a subscene script

[viral sonnet]

like loading or really creating the GOs in there? because I'd say subscenes are not really designed for that or more to the point, the workflow isn't.

[rotund token]

i am super confused

got rid of the 2x array memcpy, the quantize job just direct write to the key/value buffers in the hashmap and then the populate job only does the bucket calculation

and it's slower?!

        private struct PopulateSpatialHashMap : IJob
        {
            public NativeParallelMultiHashMap<int, int> SpatialHashMap;

            public void Execute()
            {
                this.SpatialHashMap.RecalculateBuckets();
            }
        }```

consistent as well

takes nearly 30% longer

[viral sonnet]

is a resize triggered?

[rotund token]

there is no resize in here

stashed my changes just to be 100%

so confused

[viral sonnet]

just a recalc of the index can't take this long hm

[rotund token]

stash my changes

0.58 😬

            [NoAlias] this NativeParallelMultiHashMap<TKey, TValue> hashMap)
            where TKey : unmanaged, IEquatable<TKey>
            where TValue : unmanaged
        {
#if ENABLE_UNITY_COLLECTIONS_CHECKS
            AtomicSafetyHandle.CheckWriteAndThrow(hashMap.m_Safety);
#endif
            var length = hashMap.m_MultiHashMapData.m_Buffer->allocatedIndexLength;

            var data = hashMap.GetUnsafeBucketData();
            var buckets = (int*)data.buckets;
            var nextPtrs = (int*)data.next;
            var keys = (TKey*)data.keys;

            for (var idx = 0; idx < length; idx++)
            {
                var bucket = keys[idx].GetHashCode() & data.bucketCapacityMask;
                nextPtrs[idx] = buckets[bucket];
                buckets[bucket] = idx;
            }
        }```

this is the after

this is the before```public static unsafe void ClearAndAddBatch<TKey, TValue>(
this NativeParallelMultiHashMap<TKey, TValue> hashMap,
NativeArray<TKey> keys,
NativeArray<TValue> values)
where TKey : unmanaged, IEquatable<TKey>
where TValue : unmanaged
{
CheckLengthsMatch(keys.Length, values.Length);

#if ENABLE_UNITY_COLLECTIONS_CHECKS
AtomicSafetyHandle.CheckWriteAndThrow(hashMap.m_Safety);
#endif

        hashMap.Clear();

        if (hashMap.Capacity < keys.Length)
        {
            hashMap.Capacity = keys.Length;
        }

        var data = hashMap.GetUnsafeBucketData();
        UnsafeUtility.MemCpy(data.keys, keys.GetUnsafeReadOnlyPtr(), keys.Length * UnsafeUtility.SizeOf<TKey>());
        UnsafeUtility.MemCpy(data.values, values.GetUnsafeReadOnlyPtr(), values.Length * UnsafeUtility.SizeOf<TValue>());

        var buckets = (int*)data.buckets;
        var nextPtrs = (int*)data.next;

        for (var idx = 0; idx < keys.Length; idx++)
        {
            var bucket = keys[idx].GetHashCode() & data.bucketCapacityMask;
            nextPtrs[idx] = buckets[bucket];
            buckets[bucket] = idx;
        }

        hashMap.m_MultiHashMapData.m_Buffer->allocatedIndexLength = keys.Length;
    }```

literally removed the clear, capacity resize + 2x memcpy

and its twice as slow

popping changes let's try again

[viral sonnet]

i think the issue is that the bucket/next array isnt set to -1

[rotund token]

!!!

i was clearing it but

            if (hashMap.Capacity < entityCount)
            {
                hashMap.Capacity = entityCount;
            }
            hashMap.SetLength(entityCount);```

i was doing it before the length set

[robust scaffold]

All clearing does is set length to 0. You can skip the clear and directly set length.

[rotund token]

that is not true on hash maps at all

        {
            UnsafeUtility.MemSet(data->buckets, 0xff, (data->bucketCapacityMask + 1) * 4);
            UnsafeUtility.MemSet(data->next, 0xff, (data->keyCapacity) * 4);

            for (int tls = 0; tls < JobsUtility.MaxJobThreadCount; ++tls)
            {
                data->firstFreeTLS[tls * UnsafeParallelHashMapData.IntsPerCacheLine] = -1;
            }

            data->allocatedIndexLength = 0;
        }```

it memsets the bucket/next arrays to -1

[robust scaffold]

Ah, hrm. Guess it's not a list then.

[viral sonnet]

yep, i'm using next->Resize(length, NativeArrayOptions.UninitializedMemory); buckets->Resize(bucketLength, NativeArrayOptions.UninitializedMemory); UnsafeUtility.MemSet(next->Ptr, 0xFF, length * 4); // sets everything to max, Unity uses the same method in their NativeHashMap clear UnsafeUtility.MemSet(buckets->Ptr, 0xFF, bucketLength * 4); to clear to -1

[rotund token]

there we go

twice as fast

[viral sonnet]

noice 👌

[minor sapphire]

Sup in the dots land

Looks like hash maps in the dots land

[robust scaffold]

yes

[timber ivy]

Is there like a way you can do this in unity ecs?

var w = new  World();
w.Systems.Add(new SomeSystem()):

w.Systems.Update();

[robust scaffold]

Yes, but it's pretty painful.

[timber ivy]

really lame

how do you control execution order?

I saw attributes

but

that looks painful as well.

[robust scaffold]

I mean:

That works. But doesnt sort.

[robust scaffold]

Execution is just add to a system group then maybe update before or after another system

[timber ivy]

Yes that looks painful xd

[minor sapphire]

Create groups.
Use [UpdateInGroup] in systems.
Use [UpdateBefore] and [UpdateAfter] on groups, and systems within groups

[timber ivy]

Thats really the only way?

[minor sapphire]

no

[timber ivy]

whats the other way?

[minor sapphire]

If you really really want, you tick your own groups and systems

[timber ivy]

any docs on this?

[minor sapphire]

lemme check

[timber ivy]

Does this effect oninit and ondestroy order too btw?

[robust scaffold]

Yes

[minor sapphire]

My self imposed time limit on checking has expired. Not sure 🙂

[timber ivy]

Yeah I can't find it anywhere either

Thank you though!

[minor sapphire]

it comes down to calling 'update' on a system, although I can't remember how you disable auto updating

[robust scaffold]

https://docs.unity3d.com/Packages/com.unity.entities@0.51/manual/system_update_order.html

[minor sapphire]

you can [DisableAutoCreation] but I'm not sure if that's really what you want

[timber ivy]

I mean that will work tbh

then can I just new System(); and system.OnUpdate wherever I want?

[robust scaffold]

System needs to be created through the World property or else the properties like EntityManager will not work properly. But yes.

[timber ivy]

awesome thanks

[viral sonnet]

groups and before/after cover pretty much the most use cases for ordering. does that not work for you?

[robust scaffold]

I can see cases where manual update would be nice. Like update once for monobehavior events if singletons are not possible.

[viral sonnet]

kind of hacky, requirecomponentforupdate but not have that comp around

[robust scaffold]

I need someone to verify this logic. I cant think it through:

Idx is originally 1, 2, 3... At the end, I want the value at Idx to match the resulting location of where the corresponding AABB and cents end up.

[viral sonnet]

does the tuple not require a temp variable?

[robust scaffold]

Nope. This is C# swap.

[viral sonnet]

huh pretty handy

[timber ivy]

what is the halfSize and width values being set from?

[rotund token]

Just settings

[worldly isle]

Is there a good example somewhere of using the DOTs physics for colision detection?

I have been trying to find this all over and all I can find is raycasting stuff

oh and upto date

cause all the stuff I find is out of date

[robust scaffold]

https://docs.unity3d.com/Packages/com.unity.physics@0.51/manual/collision_queries.html

That or suit up and dive into the source code.

[worldly isle]

wait so we just call hey has this thing collided all the time? that seems inefficient...

[robust scaffold]

The entire physics collision world gets regenerated / recreated every single tick. It's stateless.

Due to being stateless, what you have is "has it collided this frame". Nothing about last frame or any histories.

[worldly isle]

oh so we are not running a new calculation we are just checking the current state?

[robust scaffold]

Yep.

[worldly isle]

I feel like I am missing something here I don't see where this code belongs it just says to make a method public unsafe Entity SphereCast(float3 RayFrom, float3 RayTo, float radius) but not what class that is in or what system it needs to extend or how it gets called or anything

[robust scaffold]

https://github.com/Unity-Technologies/EntityComponentSystemSamples/tree/master/PhysicsSamples/Assets/Demos

It's probably buried somewhere in there. I'm not familiar with actually using the physics package personally.

[worldly isle]

cool beans

I am trying to learn it enough to make a youtube tutorial about it

[robust scaffold]

https://github.com/Unity-Technologies/EntityComponentSystemSamples/blob/master/PhysicsSamples/Assets/Demos/3. Query/Scripts/QueryTester.cs#L45

[viral sonnet]

seems unrealistic. 1.7ms job for 250k entities

this on the other hand. pretty much nothing

[drowsy pagoda]

What does it take to move an entity from one scene to another during runtime?

[robust scaffold]

These are float3s right? Distancesq is just dot itself. Really fast.

Yea, those percentages are clearly wrong.

[robust scaffold]

There are no such thing as "scenes" in runtime. The hierarchy you see in the inspector is just visual.

[drowsy pagoda]

Yeah I'm aware. I strictly want to do this specifically for the hierarchy 😛

[robust scaffold]

Only one way, during conversion. Use AddAdditionalEntity() in your GameObjectConversionSystem.

Otherwise, not during runtime. I asked the DOTS folks about that on the forums and they said Soon^tm.

[drowsy pagoda]

Ooof, there's that word again..."Soon"

[rotund token]

it's not entirely true, all entities in a subscene share the same shared component

and can be closed together

you can add entities into this group by simply giving them the same component

however it's not persistent, once you 'close' the subscene during runtime the entity will just be destroyed

reopening the subscene will not recreate this entity

(and when i say open/close i mean during runtime via code, not via hierarchy)

[drowsy pagoda]

I think I'm gonna try that, I don't need them to persist between play modes.

[rotund token]

but it can be useful for tying effects and other things to these entities that will cleanup at same time

[rotund token]

it wont persist within the same play session

if you close the subscene

[drowsy pagoda]

Oh!

[rotund token]

it just does destroy(allfromscene) including things you've added to it

[drowsy pagoda]

I think that's okay too in my situation. But thanks for the fine print.

[robust scaffold]

Huh, that is a neat trick.

[rotund token]

but it will just read back off disk when loading

[drowsy pagoda]

Thanks man

[viral sonnet]

yeah, sucks that profiling burst is so inaccurate for some reason 😩

[robust scaffold]

The guy who made the quote on the product page is one of the devs, I dont think lead, of Burst so there has to be a way to get accurate data

[rotund token]

these components

[drowsy pagoda]

Yeah I was just about to ask

do I just need to mess with SceneSection or both?

[rotund token]

cant remember

if you have something in the subscene referencing a prefab

that prefab will also automatically be added to subscene and instantiating off it will be into the subscene at runtime

[drowsy pagoda]

nice

[solemn hollow]

sorry i had to leave yesterday.

{
    public Entity headTile;
    public NativeList<KernelSlot> kernelSlots;
}
public struct KernelSlot
{
    public UnsafeList<Entity> tiles;
}```

thats the layout

this is essentially how it didnt work:

var tilesKeyArray = slotTilesHashMap.GetKeyArray(Allocator.Temp);
                    
                    var kernelSlotTiles = new UnsafeList<Entity>(100,Allocator.Temp);
                    intersectedCollapseKernel.kernelSlots.Add(new KernelSlot
                    {
                        tiles = kernelSlotTiles
                    });
                    
                    kernelSlotTiles.Add(tilesKeyArray[0]);
                    Debug.Log(intersectedCollapseKernel.kernelSlots[0].tiles.Length);```

that debug would always print 0

now my easy fix was to first fill the kernelSlotTiles and then add that to the kernelSlots afterwards. but i sure like to learn how id make that work. how would i access with -> ? never used it to access before.

[robust scaffold]

Hrm. Not good showing for only 10,000 entities.

[rotund token]

hehehe down to 0.28mt + 0.28st for 200k

feel like unity's would be faster than that?

[rustic rain]

Why map population is single core?

[robust scaffold]

Because I programmed this by hand it's singlethreaded for now.

[rustic rain]

I mean tertles too

[robust scaffold]

Adding to a hash map is faster in singlethreaded with a bunch of memcpys

[rustic rain]

Unity physics cause sync point as far as I remember

So maybe you should use this

Somehow

[robust scaffold]

How would sync points help?

[rustic rain]

You can calculate map capacity beforehand

[robust scaffold]

Hrm, assuming the parallelism is linear, division by 10 threads probably means 0.5ms for 10k. Which is pretty awful.

[rustic rain]

Increase it and then fill it threaded

[rotund token]

because in a single thread can now do it in <0.3ms and in multithread it takes 2.5ms per thread trying to add 1 element at a time

[rustic rain]

Huh

Is that a thing for native hash map?

[rotund token]

i have a lot of extensions for native hashmap to do batch operations

[rustic rain]

So I better always use single thread for it?

Hmm

Can you show batched add range?

I could use this one

[rotund token]

^

[robust scaffold]

I wonder, would it be faster if during that quantized portion, you instead atomic add to a NA<int> containing counters for each grid square. Next a small singlethreaded jobs that calculate the offset for each grid. Then a third multithreaded write to another NA<Entity> now that you have the offset for the grid and the index of that entity.

[rustic rain]

Huh

Maybe I can speed up target finding by a margin with that

But I assume

I should always use single thread for filling map, right?

[robust scaffold]

profile it, sometimes it faster, sometimes it's slower

it's just a simple method change so just profile it.

[rustic rain]

It's not

[robust scaffold]

Or do both and profile the changes

[rustic rain]

Makes me refactor method

Which is a bit more complex than simply changing schedule method

[rotund token]

#archived-dots message

if you want to see difference from when i made it parallel to single thread batch operation

(and today i double the speed of the single thread operation)

[rustic rain]

Really interesting

Batching is a goal I guess

[rotund token]

the gotcha is this is only safe on a hashmap if it's empty

and if you're using non-multi version it won't check for duplicates

[rustic rain]

There are no duplicates in my case

[rotund token]

(it doesn't check for duplicates in multi either but the container allows it)

[rustic rain]

Oh wait

My map is multi

I forgot to mention

[rotund token]

yeah that's fine that's the one i linked

[rustic rain]

Ah

[rotund token]

you can add duplicates to that

normally

[rustic rain]

I simply need to fill entities based on sharecomp separation

Where they all share same id

So that should be easy to batch

[rustic rain]

Hmm

is there a way to have singleton blob?

I assume I could use World extension for that...

but would love some less managed option

[rotund token]

apart from being immutable, what advantages do you have using a singleton blob over a singleton entity?

[rustic rain]

I decided to use combination of both

blob for value

entity for tag whether it's active or not

I use blob because having I need a way to access data from anywhere

and since it's never removed

or moved

I can use singleton approach

it's kind of a variable like Time

[timber ivy]

im having a hard time finding an up to date solution for this

how do you add a component to an entity in a job you run with entities.foreach().scheduleparallel

[rotund token]

commandbuffer

[timber ivy]

In the sample posted here

https://docs.unity3d.com/Packages/com.unity.entities@0.51/manual/entity_command_buffer.html

does this.Dependency.Complete(); have to be called

or can i just comment that out and it would still work?

[rustic rain]

no

it's an example how it works

all you need to do is create ECB

and then addjob handler to producer

in ECB system

a bit below an actual example

of how it should look like

[timber ivy]

So you have to write your own ecb system?

[rustic rain]

no

there are default ones

[timber ivy]

ok cool thank you

Can you create the command buffer in system init and use it later or does it have to be recreated each frame?

[rotund token]

every frame

[timber ivy]

ecb has no get component is that just safe to use then?

[rustic rain]

GetComponent is codegen in foreach loop

it implements ComponentDataFromEntity for you

[timber ivy]

Is there no way to run this as a job?

        EntityCommandBufferSystem sys =
                World.GetExistingSystem<BeginSimulationEntityCommandBufferSystem>();

        // Create a command buffer that will be played back
        // and disposed by MyECBSystem.
        EntityCommandBuffer ecb = sys.CreateCommandBuffer();
        var pos = new float2(cam.position.x, cam.position.z);
        var sceneSystem = World.GetOrCreateSystem<SceneSystem>();
        Entities.WithAll<WorldChunkComponent>().ForEach((Entity e, ref WorldChunkComponent chunk) =>
        {
            if (math.distance(pos, chunk.position) <= 400)
            {
                sceneSystem.LoadSceneAsync(chunk.hash);
                ecb.AddComponent<RelevantComponent>(e);
            }
            else
            {
                if(HasComponent<RelevantComponent>(e) == true)
                {
                    sceneSystem.UnloadScene(chunk.hash);
                    ecb.RemoveComponent<RelevantComponent>(e);
                }
            }
        }).ScheduleParallel();

Passing sceneSystem is causing an exception since im passing a non value type

[rustic rain]

well, there is

but I have a feeling

that this job is run on simple entity

or not?

oh wait, is that dynamic culling system?

anyways

you can load scenes

by creating entities

[timber ivy]

Loads the map in and out of memory with subscenes

[timber ivy]

Can you elaborate a little more on that?

[rustic rain]

take a look at what LoadSceneAsync does

pretty sure it creates scene entity

        void LoadEntitySceneAsync(Entity sceneEntity, LoadParameters parameters)
        {
            var requestSceneLoaded = CreateRequestSceneLoaded(parameters);

            EntityManager.AddComponentData(sceneEntity, requestSceneLoaded);

            if (parameters.AutoLoad && EntityManager.HasComponent<ResolvedSectionEntity>(sceneEntity))
            {
                foreach (var s in EntityManager.GetBuffer<ResolvedSectionEntity>(sceneEntity))
                    EntityManager.AddComponentData(s.SectionEntity, requestSceneLoaded);
            }
        }

[timber ivy]

yep

its nested in there pretty deep

but its in there

I wont be able to do that in a job anywyas will I?

[rustic rain]

        Entity CreateSceneEntity(Hash128 sceneGUID, LoadParameters parameters = default)
        {
            var requestSceneLoaded = CreateRequestSceneLoaded(parameters);
            var sceneEntity = EntityManager.CreateEntity();
            EntityManager.AddComponentData(sceneEntity, new SceneReference {SceneGUID = sceneGUID});
            EntityManager.AddComponentData(sceneEntity, requestSceneLoaded);
            return sceneEntity;
        }

[rustic rain]

loading subscene is literally just creating entity

that triggers SceneSystem update

which will load it

this is creating scene entity from scratch

but you should instead first check whether scene entity is created already

basically

you can resolve it all during your world chunk creation

[timber ivy]

That is done in the editor

[rustic rain]

so you can simply pass an entity to one of it's fields

and then use it

to load/unload subscene

btw, subscenes can also divide into sections

[timber ivy]

Wym?

Like they can be parented and stuff?

[rustic rain]

SubScenes support sections

that's why they have 2 shared components

not

1

you can load them independently

I haven't really touched any of that