#archived-dots

1 messages · Page 9 of 1

rotund token
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but quantizing to increase chance

# 
{
    Value; // entity.index / 8 for example
}```
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was best i could think of

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but yeah needs unmanaged shard components

viral sonnet
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CDFE is really fast, it still has to do this every time return ChunkDataUtility.GetComponentDataWithTypeRO(m_EntityInChunkByEntity[entity.Index].Chunk, m_ArchetypeByEntity[entity.Index], m_EntityInChunkByEntity[entity.Index].IndexInChunk, typeIndex, ref cache);

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m_EntityInChunkByEntity[entity.Index].Chunk could be totally cached if you access several comps of the same entity

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same goes for archetype

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before i start doing anything weird. i should improve on this in my CDFE extensions

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when you know the chunk and archetype, it's nearly a direct lookup

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i suppose this will be a cache hit on the 2nd lookup but still.

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talking about the previous thing. chunk DBs woukd be great

winged bane
#

can you design the system without the need to keep them referencing each other?

viral sonnet
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i could merge the data but that has (worse) performance implications that i want to avoid

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hm this collisionFilter isn't working: BelongsTo = (uint) 1 << (team + 2), // offset the teamId, CollidesWith = (uint) (0xffffffff & ~(1 << (team + 2))), any clue what's wrong here?

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should hit everything except the own layer

rotund token
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i think you might have a better time

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using GroupIndex as team

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unless you use GroupIndex for something else?

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actually i guess it depends if you are doing actual collisions

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i forgot we aren't so this works very well

viral sonnet
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i haven't figured out the groupIndex yet. i basically need a collisionFilter that either targets the other team or its own. does that work with the groupIndex?

rotund token
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If the value in both objects is equal and positive, the objects always collide. If the value in both objects is equal and negative, the objects never collide.

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it's pretty useful

viral sonnet
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hm, yeah. the comment confused me for the longest time 😄 it's more simple than i imagined. i'll test it out. still no idea why the above isn't working. the bitmask should be correct. 🤔

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well, i still have no idea what the thing about positive or negative means

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yeah, actually i'm still confused 😄

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so what would be a collisionfilter to get the colliders from the other team?

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does groupIndex interact with belongsTo/CollidesWith?

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oh there's the code below for IsCollisionEnabled. that answers at least some of my questions

rotund token
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yeah just look at the code

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i think the important part for your issue above is

# 
        (filterA.BelongsTo & filterB.CollidesWith) != 0 &&
        (filterB.BelongsTo & filterA.CollidesWith) != 0;```
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it must collide both ways

drowsy pagoda
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what is ScheduleByRef and RunByRef etc all about?

rotund token
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if you have really large jobs

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can be a slight performance improvement

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in general, i would not worry about them

viral sonnet
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i had a pretty big job struct at one point and i haven't seen any difference. no idea what it's really used for and how big a jobstruct is supposed to be then

timber ivy
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is there a way to query for entities where a field on a component is a certain value?

viral sonnet
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nope

drowsy pagoda
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For what reason would _directiveSystem.Update(); not trigger the SystemBase.OnUpdate event? Or am I misunderstanding this?

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typically system is not running. And once in a while I need to manually wake it up if since no queries are met. Trying to avoid AlwaysUpdateSystem attribute

rustic rain
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Oh wait

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It must run

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And call on update

drowsy pagoda
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Yeah I thought so to, but logs say different.

rustic rain
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How do you call it?

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I mean how do you get a reference to system

drowsy pagoda
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_directiveSystem = World.GetOrCreateSystem<DirectiveSystem>();

rustic rain
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Hmm

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I got my reference by iterating system's list

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Maybe that can be potentially a case?

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Allthough doubt

drowsy pagoda
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I don't know. This method is used by Unity in docs. Seems to be the norm.

rotund token
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OnUpdate won't run if you aren't meeting requirements to run system

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such as system is disabled or there is no query with matching entities

# 
        {
            // ...

            if (Enabled && ShouldRunSystem())
            {
                // ...
                OnUpdate();```
rustic rain
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Hmm

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Oooh

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Now I get why my system's run

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They didn't run because they are part of togglable system which simply stops updating them

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So manual update worked like expected

timber ivy
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is entitymanager slow?

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things like creating entities, setting component data etc outside of systems

rustic rain
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it's the fastest way possible for single entity

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combine it with burst

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using ISystem

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and it'll be even faster

timber ivy
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what if its not an ECS system

rustic rain
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well, not ECS systems don't have EntityManager

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😅

timber ivy
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Yes they do World.DefaultGameObjectInjectionWorld.EntityManager

rustic rain
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this is you accessing ECS world

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still

timber ivy
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what I mean is

rustic rain
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anyways

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you can do it

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anyway

timber ivy
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I have some code that executes scripts via reflection

rustic rain
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EntityManager is the fastest solution for single actions

timber ivy
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ik the reflection will take a hit to perf

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alright awesome

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and then entities.foreacch is fastest for multiple actions?

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will using : ISystem on the scripts be relevant tho?

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even tho they will just be calling functions that will call another dll

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can burst optimize reflection?

rustic rain
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no

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burst only works with value types

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and if you want some random bursted action

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it'll only work with pointers

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to those values

rustic rain
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behind codegen

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what it does:
Creates IJobEntityBatch struct with your code
Grabs all relevant to query chunks, gets all components
And then runs your lambda code on those components

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you can always iterate chunks manually btw

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I do it sometimes, when I need precision regarding chunks

timber ivy
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i haven't even read into chunks yet tbh

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not even sure what they are atm

rustic rain
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just take a look at examples of IJobEntityBatc

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this is what Entities.ForEach under the hood

timber ivy
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awesome thank you!

timber ivy
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Is there anything like continue that I can use inside entities.foreach?

devout prairie
dire ingot
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Hey, how can I change PhysicsMaterialTemplate of an entity through code? I want to change it physics once on trigger, but i'm not sure from which component can I get the reference to change it

devout prairie
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which properties are you looking to change?

dire ingot
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Filter, Friction, Resitution

devout prairie
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This is old code but it shows how to change filter of a collider:

unknown.png
timber ivy
# 
var relevants = relevantQuery.ToComponentDataArray<RelevantComponent>(Allocator.Temp);
        var chunks = relevantQuery.ToComponentDataArray<WorldChunkComponent>(Allocator.Temp);
        var entities = relevantQuery.ToEntityArray(Allocator.Temp);

        for(int i = 0; i < entities.Length; i++)
        {
          chunks[i].val = 322;

is something like this valid or will I need to use entity manager to actually set the values of the component?

rotund token
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ToComponentDataArray is a copy

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General rule of thumb in C#
To = copy
As = reinterpret (direct access)

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     chunks[i].val = 322;

also pretty sure that is a compile error as it's not ref returned

timber ivy
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ah yeah i have to do new and assign a new value to the index of the array

timber ivy
rustic rain
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you need ComponentType handles

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oh wait

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hold on

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are you working with actual chunks, or?

timber ivy
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no

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this is world chunks

rustic rain
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confusing naming

timber ivy
# 

relevantQuery = GetEntityQuery(ComponentType.ReadOnly<RelevantComponent>(), ComponentType.ReadWrite<WorldChunkComponent>());
    }
    protected override void OnUpdate()
    {
        var relevants = relevantQuery.ToComponentDataArray<RelevantComponent>(Allocator.Temp);
        var chunks = relevantQuery.ToComponentDataArray<WorldChunkComponent>(Allocator.Temp);
        var entities = relevantQuery.ToEntityArray(Allocator.Temp);

        for(int i = 0; i < entities.Length; i++)
        {
          chunks[i] = new WorldChunkComponent
rotund token
timber ivy
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so would doing that mean the values written to chunks[i] will be reflected since I have readWrite on it

rotund token
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but why are you doing ti this way

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instead of just using an entities foreach?

timber ivy
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Because you can't call sceneSystem.Loadsubsceneasync in entities.foreach

rotund token
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oh is that what you're trying to do

rustic rain
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it makes structural change

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so after you done it

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all your arrays become invalid

rotund token
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just load it via components like I do?

# 
this.CommandBuffer.AddComponent<RequestSceneLoaded>(batchIndex, entities[i]);
foreach (var section in resolvedSectionEntity.AsNativeArray())
{
    this.CommandBuffer.AddComponent<RequestSceneLoaded>(batchIndex, section.SectionEntity);
}

// Unload
this.CommandBuffer.RemoveComponent<RequestSceneLoaded>(batchIndex, entities[i]);
foreach (var section in resolvedSectionEntity.AsNativeArray())
{
    this.CommandBuffer.RemoveComponent<RequestSceneLoaded>(batchIndex, section.SectionEntity);
}```
timber ivy
#

I tried doing it this way but had no luck. Care to share some more of your code? particularly entity creation?

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or are you just letting them exist from the world start and iterating over them?

rotund token
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I have a system that in OnCreate
foreach (var subScene in Object.FindObjectsOfType<SubScene>())
finds all subscenes then loads them (but not auto load, just creates their entities)

this.EntityManager.AddComponentObject(entity, subScene);

waitingForLoad.Add(entity);

if (subSceneLoadConfig.LoadingMode == SubSceneLoadMode.BoundingVolume)
{
    volumes.Add(subSceneLoadConfig, entity);
}```
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disables updating until the subscenes are loaded

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so i dont need to add requireforupdate for all my setting files in systems

timber ivy
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could I see the query you're performing before execcuting this code?

this.CommandBuffer.AddComponent<RequestSceneLoaded>(batchIndex, entities[i]);
foreach (var section in resolvedSectionEntity.AsNativeArray())
{
    this.CommandBuffer.AddComponent<RequestSceneLoaded>(batchIndex, section.SectionEntity);
}
rotund token
#

this.subsceneQuery = this.GetEntityQuery(ComponentType.ReadOnly<ResolvedSectionEntity>(), ComponentType.ReadOnly<LoadWithBoundingVolume>());

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wont help much

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this is my in range subscene system

timber ivy
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if a subscene has the RequestSceneLoadedComponent that means the subscene is loading or already loaded?

rotund token
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yeah subscenes are basically just loaded when RequestSceneLoaded is added

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and unloaded when RequestSceneLoaded is removed

timber ivy
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alright awesome

rotund token
#

from itself + all it's sections

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and sections are in its RequestSceneLoaded buffer

timber ivy
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are sections related to position in the world or is it sectioned off by some other data?

rotund token
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you'll have to very specifically add sections yourself

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you probably won't need them

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i think the only use i know of atm that they are used

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is for HLOD

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unity uses them to split that or something

timber ivy
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wouldn't you get better loading speed if you had one huge subscene that only loaded sections relevant to you?

rotund token
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what benefit does that over having lots of subscenes

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and only loading subscenes that are relevant to you?

timber ivy
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nearby subscenes

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based on distance

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I dont need the whole map loaded at once

timber ivy
rotund token
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no

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this is not loading any data

timber ivy
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ok

rotund token
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data is only loaded when you put RequestSceneLoaded

timber ivy
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this is way simpler than what I was trying to do

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thank you for the insight

rotund token
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i have an extra script i attach to subscenes with a few options

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that sets the mode to autoload (synchronized optional), load from volume (distance from player/s) and on demand which are basically just manually triggered from other sources

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above code was from the volume path

timber ivy
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thats a good idea, I might steal that from you

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can I add arbitrary components to the subscene entities themselves then without messing up the SceneSystem?

rotund token
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yeah

timber ivy
rotund token
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it's just part of dynamic buffer

timber ivy
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So each entity for each subscene has a ResolvedSectionEntity component and a dynamic buffer of them as well?

rustic rain
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not an issue for PC (mostly), but is a bit important for mobile

rotund token
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addressables is specifically designed to duplicate assets to allow unloading

timber ivy
rotund token
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havent dived into profiling memory that closely with subscenes because i haven't had to

viral sonnet
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noice brought my targetInfoSystem down from 2.2 to 1.2ms. all data is now local to the entity. CDFE writing was killing it.

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didn't even realize it's that bad because a write is costly anyways. BUT a random write. ooof

devout prairie
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ahh

viral sonnet
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AMD uProf is pretty nice

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i like it more than vtune

pliant pike
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yep CDFE is bad mkay

worldly isle
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Thank you

viral sonnet
worldly isle
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does not need to be actual events

timber ivy
# 
            var e = sceneSystem.LoadSceneAsync(pair.Value, new SceneSystem.LoadParameters()
            {
                AutoLoad = false,
                Flags = SceneLoadFlags.LoadAsGOScene | SceneLoadFlags.DisableAutoLoad
            });
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I suspect I need to get rid of the loadasgoscene flag but then nothing from the scene renders. maybe a problem with conversion if that is the case?

devout prairie
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the unity physics samples has an example of a stateful onenter/exit system, where it uses 'events' to keep track of these things

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it's kinda complex and not the fastest system but you can use it as a basis for doing that

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just to point that out in addition to what Enzi linked above

worldly isle
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or better yet are any of the entities with Tag FooBar currently colliding with anything

rustic rain
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keep it in mind if you have a lot of things that will collide and create trigger events

pliant pike
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what ways are people using to destroy a lot of entitys 🤔

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it seems a bit excessive to use an ECB to add a component to those marked for death and then another for destroying them

devout prairie
# worldly isle I am fine with handleing all of that my self and planned to actually. I just nee...

I think the only supported way is to use events tbh.. otherwise the physics system doesn't expose any of the collisions.. this is just my understanding so far though. Alternative is manually do collider casts and check the results. Afaik there is a way to register 'callbacks' during the solver phase which allow you to inject modifications to simulation behaviour, so i mean maybe that's a possible way, but i'd probably guess that's not very fast.

rustic rain
pliant pike
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yeah I still need to know which ones to destroy though

rustic rain
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how do you figure it in the first place?

pliant pike
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I'm currently just doing it immediately on health equals zero with entmanager

rustic rain
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hm

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well

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there is nothing wrong with having special destroy tag

pliant pike
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but that's not going to work well later for efficiency reasons

rustic rain
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entity destruction pipeline is actually a good thing

pliant pike
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yeah I guess I'm just trying to figure out where I want the bottleneck to be

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do I have a destruction system that searches through all 10,000 entities to find the ones to destroy or do I do it another way 🤔

rustic rain
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I mean

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you could potentially make a pipeline for health changes

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so anytime you change health to smth

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you also check for 0

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and if it is 0 you attach destroy tag

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alternatively, you do queries based of Change version

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which would make searches over 10k entities faster

pliant pike
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yeah to be honest I don't want to use an ECB for that part because they are kind of slow

rustic rain
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kind of

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you don't always have entities to destroy, aren't you?

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meanwhile doing 10k loop

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on main thread

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seems way worse

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unlike doing 10k loop on one of 16 threads

pliant pike
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yeah I guess I might try systemstate component with a boolean 🤔

rustic rain
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that works too

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having state component with data "dead" or "alive"

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but

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you will have to make some kind of random access for it

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otherwise if you just ref it

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you'll change version

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no matter if you write to it or not

pliant pike
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huh?

rustic rain
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I wonder if ComponentDataFromEntity with write access changes version if you don't write to it at all

rustic rain
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you check whether chunk has been written on selected Component

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if it wasn't written

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why check chunk at all?

pliant pike
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I've never used that, interesting, I might try that, thanks 🤔

rustic rain
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@rotund token do you happen to know whether ComponentDataFromEntity affect changes filter of all entities, or only of chunk you read/written to?

pliant pike
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ok that's weird its not even adding the Isystemstatecomponent 😕

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yeah its weird a normal component adds fine in a IConvertGameObjectToEntity but not an ISystemstateComponent

safe lintel
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dont think you can add a systemstate component in conversion

viral sonnet
#

the problem with death states is structural changes and often some postprocessing. so a bool comp works quite well. the destruction can then be delayed and a change filter can trigger on death state comp changes

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that also requires some good change filtering so you don't have to check the deathstate mitiple times for each frame

viral sonnet
viral sonnet
rustic rain
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so only chunk to where you wrote

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that's good

rustic rain
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just add normal

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no need for state

pliant pike
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Well that's annoying

viral sonnet
#

you are not the first 🙂

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not that I'm counting but you are the 4th who criticises that 😄

robust scaffold
#

I'm pretty sure you can use system state components in conversion, just not incremental. You must rebuild your entire entity cache for the sub scene on every change if you use system states

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Pretty sure. I saw the warning and I noped out real fast.

rustic rain
#

They only exist in dst conversion world

latent quest
#

How would one find where or how a structural change is coming from. I have one that I'm doing little if anything before yet it's giving an error when I call a GetComponentDataFromEntity using an entity pulled from a NativeList. I hardly even understand what constitutes a structural changes so I'm not even sure where to start since I've done a bunch of Debug.Loging to figure out if something is invalidated early on but nothing seems to be...

viral sonnet
latent quest
#

Dankeschön, seems I just needed refresh my GetComponentDataFromEntity... ( ;-v-)

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I will keep the structural changes in mind as I develop, not exactly something I normally have to think about :P

agile cradle
#

Hi. Is there any way to avoid dots TransformConversion which decouples standard Transform monobeh into several components (local to world, translation, rotation). I'm going to use hybrid approach and use standard Transform as entity component and just want to get rid of unused resources.

viral sonnet
#

it's not avoidable but you can remove the comps at the conversion stage

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just dstManager.remove

viral sonnet
latent quest
#

I have absolutely no RemoveComponent or AddComponent calls if that's what you mean. But even then, how would tags be used if you can't use Remove/Add component calls? I understand ftmp why ofc, but having absolutely none seems hard with larger scale and complex projects.

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Add/Remove component calls for components that last for a while at least.

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Would just completely recreating the entity be a better option in that case?

viral sonnet
#

the short answer is, you don't use dynamic tags 🙂 at least not for now. unity will improve on this in entities 1.0 with enabled/disabled state for comps which shouldn't be too far off now

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recreating is basically what happens. add/remove comps will memcpy the entity to another archetype/chunk

latent quest
#

Interesting. If the new component will (theoretically) last for the rest of the game, would it be okay to add/remove components or recreate the entity?

robust scaffold
robust scaffold
#

That's in a GameObjectConversionSystem. Removes the default transform components from everything.

agile cradle
#

I've made it work in IConvertGameObjectToEntity monobeh. But thank you for pointing me to a more universal approach)

viral sonnet
latent quest
#

Ah, gotcha. So no mass add/remove but now and again for long-term is more okay.

robust scaffold
#

Rule of thumb is to avoid structural changes, almost at all costs. There are cases where it's preferred, such as when you can do so for entire chunks at a time.

rotund token
#

just avoid changing state every frame

robust scaffold
#

Always, always, turn on the profiler to see if what you're doing is having any impact.

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Just multiply the expect number of entities by 100 or until you reach 50,000 to get decent measurable and comparable performance values.

viral sonnet
#

yep, i agree with all that

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so don't use comps as kind of event. that will bite you in the ass sooner or later

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i say that because most, me included, start with that kind of approach

robust scaffold
viral sonnet
#

tertle, have you ever used amd uprof?

agile cradle
#

Can I prevent converting specific monobeh into component in ConvertAndInjectGameObject mode? I have a lot of binders which create an appropriate dots components and bind them to parent entity.

unknown.png unknown.png
robust scaffold
agile cradle
#

It is my custom interface)

robust scaffold
#

Ah, you might need to call conversionSystem.DeclareAssetDependency(mo.transform)

viral sonnet
#

damn blob data is the bane of cache misses 😦

robust scaffold
viral sonnet
#

yeah but access is random

robust scaffold
#

Well, that's just random access

viral sonnet
#

i don't really know why it's missing that hard. i access the same blob 250k times. you'd think it's in the cache

robust scaffold
viral sonnet
#

cacheline, L1 is 32k more than enough that it should stay in L1 while the iteration is going on

robust scaffold
#

It can fit maybe a struct (for 3D) or two (for 2D, which is why I'm wasting so much time on my own physic engine

agile cradle
robust scaffold
robust scaffold
viral sonnet
#

i've profiled in a build but sure, many things are running

rotund token
#

might surprise you but i actually barely profile

viral sonnet
#

hehe, well, just want to say it's a great tool and worth a look when you are on amd

rotund token
#

i just try to write my code in a way that i know is fast

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when a system is done i have a quick look at unity profiler to make sure it meets my expectations and needs

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and then i move onto something else

viral sonnet
#

hm, i think i want to memcpy a blob to test something. is there already something in place?

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no idea how to get the actual size

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this looks good

unknown.png
robust scaffold
#

Sizeof just gets the size of the struct, not the actual size of the array

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If blob asset header was 2 ints, sizeof will return 8.

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I think that might work

hot basin
viral sonnet
#

yep that's the problem. it's a lot of counting, BlobPtr, the struct if it exists. BlobArray, the elements, etc...

robust scaffold
viral sonnet
#

that's why i posted the above code. length seems to be stored in the header. they need to know when serializing

robust scaffold
#

I give up. Im just gonna copy paste Unity's BVH.

#

They clearly know what they're doing.

winged bane
#

is there a reason why you had wanted to create your own?

robust scaffold
#

stable as in vibrations, not the code issue.

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Even if you lock rotation and lock the Z axis, the generic math optimizing 3D triangle mesh collision solver results in poor collision realism.

#

Unity's BVH construction is brilliant. Far beyond anything I can code. But once I nail it down, I'm going back to trusty Box2D and pulling their collision solver.

#

Box2D had the original physics BVH construction but singlethreaded and not quite vectorized as Unity's. So I'm basically copy pasting Box2D and trying to merge in unity's BVH. And why? Because unity fired everyone working on 2D so they wont do this themselves despite being incredibly easy to do so.

#

In 3 or 4 years they'll probably do it and when that happens, I'm deleting my physics folder and transferring to a Unity supported platform.

winged bane
#

physics is scary

robust scaffold
#

It's still a good educational opportunity. Knowing how to construct a BVH is pretty key for any graphics programmer... despite not being one or entering a field remotely close. But still nice to know as a hobby.

winged bane
#

I have spent the good part of a year implementing isosurfaces in dots but havent needed BVH

#

yet

robust scaffold
# winged bane physics is scary

It's a black box in many engines. Take a moment to peak inside and you'll learn a lot about how to design your game that works with the physics engine instead of unknowningly against.

winged bane
#

Im just hoping DOTS physics can handle stuff rolling down the hill, calculate hit for weapon swing

robust scaffold
#

Probably... should. It's a very good 3D physics engine.

winged bane
#

the parts I dont want to think are the time it takes to load a collision mesh

robust scaffold
#

It does make some questionable choices in the quest for stateless deterministic but still good.

viral sonnet
#

how can 2 profilers show timings for a path that's not even executed? 😄

robust scaffold
viral sonnet
#

i put a debug.log in there

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and it's a switch of data i know

robust scaffold
#

Well, for one, Unity's BVH singlethreaded builder phase is a lot more purple and VP* than mine. So props on them.

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Hrm. Well first run of the copy paste code didnt work so well. It uhhh, hard crashed unity.

robust scaffold
#

@viral sonnet Cries in inferior comp. Copied line by line from unity.

unknown.png
viral sonnet
#

hehe

#

so I think I figured out what's happening. the code paths are very similar so burst just merges them and aligns the jump. for some reason the pdb or whatever doesn't get that though and it's always highlighting the line if (targetTeamId == ...)

unknown.png
#

i'm now questioning if these tools currently are wasting my time ^^

robust scaffold
viral sonnet
#

i am months past this point 😂

robust scaffold
#

I wouldnt know specifically what the change did to result in the performance increase or decrease, just that it works or not. Simple enough for me.

viral sonnet
#

now I'm more into which trade offs are for the best

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i think i can make some nice optimizations to CDFE 🙂 fingers crossed

#

not sure how to do it right now because this damn data i need is private ...

# 
        {
            return ChunkDataUtility.GetComponentDataWithTypeRW(m_EntityInChunkByEntity[entity.Index].Chunk, m_ArchetypeByEntity[entity.Index], m_EntityInChunkByEntity[entity.Index].IndexInChunk, typeIndex, globalVersion, ref cache);
        }``` curious, they are looking up the archetype of the entity when the chunk already has the archetype*
rotund token
#

does it hugely matter though?

#

it's an indexer not a hash lookup or something

#

but yeah this is only done in the cache version

#

it's done as you say for normal lookup

viral sonnet
#

sheet, i need a better testing ground. i just realized i've brought this down to 1 CDFE lookup to get the target stats ptr.

#

performance test it is 😄

viral sonnet
#

what the hell, GetComponentDataFromEntity is internal in EntityManager?

#

how am i supposed to get this in a performance test then? i'd need a systemState

viral sonnet
#

as expected, it's not too big but it's something. 1mil entities, 4 lookups

unknown.png
pliant pike
#

I don't suppose anyone knows what Solver.ParallelSolverJob is in the profiler

#

because I have shedloads all over the place

balmy thistle
#

Going out on a limb here - I think it's physics related

#

don't quote me

pliant pike
#

yeah I think you may be right I turned on flow events and that seems to indicate it

viral sonnet
#

that was working at some point var hitEntity = closestHit.Entity; Debug.Log($"hit {hitEntity}"); now it outputs hit Unity.Entities.Entity what happened?

robust scaffold
viral sonnet
#

that's managed. i mean it worked, like it was written. pretty old code

#

ToFixedString works. weird. must be something new in 2021.

#

having a really bad day with weird shit InvalidOperationException: The previously scheduled job Broadphase:PrepareStaticBodyDataJob writes to the Unity.Collections.NativeArray`1[Unity.Physics.CollisionFilter] PrepareStaticBodyDataJob.FiltersOut. You are trying to schedule a new job HybridTargetPicker:HybridTargetPickerJob, which reads from the same Unity.Collections.NativeArray`1[Unity.Physics.CollisionFilter] (via HybridTargetPickerJob.JobData.collisionWorld.Broadphase.m_StaticTree.BodyFilters). To guarantee safety, you must include Broadphase:PrepareStaticBodyDataJob as a dependency of the newly scheduled job. what's up with that? previously it complained about writing to collisionWorld where I forgot the [ReadOnly] tag so explainable. this one though. no idea what this is about. it's a simple raycast. collisionWorld.CastRay(input, out RaycastHit closestHit) what's that about writing to collisionFilter?

#

and I register the system protected override void OnStartRunning() { this.RegisterPhysicsRuntimeSystemReadOnly(); } usually that fixed weird dependency problems

viral sonnet
#

and that's why i hate automagic stuff. it failed me. the job was scheduled with no dependency -.-

robust scaffold
#

I am 80% to the point of writing my own roslyn code gen to make a IJobEntityBatchGen that passes in NativeArrays instead of ref variables.

#

It cant be that hard, right?

viral sonnet
#

what would be the difference really?

robust scaffold
viral sonnet
#

they use TransformAspect, not as ref but writing back?

#

guess you could copy the IJobEntity implementation

robust scaffold
robust scaffold
#

Shouldnt be that hard to just put something together though.... shouldn't... But i just dont like having to open up and then compile a second project just to get a gen spinned up.

viral sonnet
#

just add it as a package then

#

source is mostly here com.unity.entities@0.51.1-preview.21\Unity.Entities\SourceGenerators\Source~\JobEntity

robust scaffold
#

oh my god

#

im dead

viral sonnet
#

and there's a base IJobEntity.cs at com.unity.entities@0.51.1-preview.21\Unity.Entities

#

i've setup quite a few times pointers to some comp for fast access without lookups. this current one i'm setting up. it's just not working right. i only run the code with DidOrderChange but then it's not working. when i run every frame it's okay. now i thought, okay, the other entity goes through some structural change I'm not aware of. just flip the direction. same thing. 😦

#

i dunno about this codegen. i'm really fast with copy/paste so in like 99% i don't care about it 😄

robust scaffold
#

Also, this is why IJob is not burst schedulable:

unknown.png
viral sonnet
#

there's a performance hit??

robust scaffold
viral sonnet
#

oh what. not what i expected. why is that?

#

because of the refs?

rustic rain
#

it is bursted for me

robust scaffold
rustic rain
#

I think...

robust scaffold
#

It's literally using typeof() and (object). Both are managed.

robust scaffold
# viral sonnet because of the refs?

Things like the mem calls are not reliably recognized by burst. You need to do them yourself. And you cant separate for loops to maximize vectorizations.

#

Like these two for loops are separated. The first is recognized by burst as just 2 float4s and is combined into a single VP operation per line. The second requires a conditional and thus doesnt vectorize. IJobEntity does not allow for this type of coding since it only passes in the ref of a single element.

unknown.png
viral sonnet
#

i don't know why they bother so much with codegen. someone on the team must have a real knack for it

robust scaffold
#

Code gen is great. Cuts down on the boilerplate. Which is GetComponentTypeHandle and then GetNativeArray

viral sonnet
#

sure at some level, but this is silly

#

works against their own compiler

robust scaffold
#

They just need to offer a code gen'ed IJobEntityBatch that is basically IJobEntity but walks back one step.

robust scaffold
viral sonnet
#

yeah agreed

#

IJE is too much

rustic rain
viral sonnet
robust scaffold
#

Or pointers and then BatchInChunk.Count for length.

robust scaffold
rustic rain
#

ugh, don't really get why reference values are a problem

robust scaffold
rustic rain
#

why would you want to do mem operations xD

#

I'd guess it's like the latest thing you want to do

#

and that's what Unity wants to avoid devs from using

#

by providing other tools

robust scaffold
#

MemCpy, MemClear, MemCpyStride. All orders of magnitude faster than just a for loop set equals to if Burst fails to recognize.

#

And burst, despite how amazing it is, is not really that good at recognizing array wide operations if it's embedded inside a lot of other code.

rustic rain
robust scaffold
#

And that results in calling MemCpy over and over again. Along with the need to pass in the batch count which, if you're using any subdivisions, can not be guarenteed.

rustic rain
#

I think you're just micromanaging nanoseconds

robust scaffold
#

Memcpy has clear benefits in the milli and even centi-seconds compared to a for loop set.

#

Manual vectorization is in the nanoseconds sure, but the mem operations are very powerful

rustic rain
#

and you are not stopped from using them

robust scaffold
#

Yes, but I want a code genned version, that is the entire conversation.

viral sonnet
#

teh fk is going on. the pointer to the comp is moving all the time! WHY!

rustic rain
#

structural changes?

viral sonnet
#

not even a single one

robust scaffold
#

The chunks themselves might be a bunch of managed arrays that Unity calls fix on before passing around.

rustic rain
#

no, that one is fully unmanaged

robust scaffold
#

I doubt it though but that's the only reason why the pointer is floating around

viral sonnet
#

the only explanation that is more likely, i'm dumb 😄 i'm logging other entities

#

and yeah, of course it must be a structural change. the first setup that happens has a wrong pointer. some form of structural change must happen. the 2nd time the pointer is set, it stays constant

#

what i don't know now, why isn't orderChange picking this up?

rustic rain
#

maybe it changed for other chunk?

viral sonnet
#

wdym, other chunk? that shouldn't matter, right?

#

ohh i get it ... i'm skipping any ptrs that are not null even when a order change occured. today isn't really my day ...

#

working fine now 😄

robust scaffold
#

welll fuck, my copy pasted BVH builder doesnt work.... gotta comb line by line without reference to figure out what went wrong

viral sonnet
#

oh god 😄 good luck

rustic rain
#

not sure if it's true

viral sonnet
#

it's true 🙂 i have no idea why i assumed i can skip ptrs that were already setup.

gilded glacier
#

question about principles - if a system behaviour is performed not every frame, but only when it's "called" (an entity the system queries, with a certain command/event component is created temporarily for a frame or so), should it be a system ?

#

shouldn't it be a function that can be called by some "supersystem" that would otherwise create those event entities ?

#

the IJobEntity seems to be this sort of function while not being a system itself

robust scaffold
gilded glacier
#

damn it, I hoped for a definitive answer

robust scaffold
#

Systems and scheduling of jobs is cheap, to a point.

gilded glacier
#

as soon as something isn't exact, my brain won't stop bugging me

robust scaffold
#

Is this an event based off an entity existing (RequireSingletonForUpdate) or is this an event firing off a component returning true?

gilded glacier
#

the latter

#

having a singleton for this probably wouldn't be very flexible

robust scaffold
robust scaffold
#

If it lasts for seconds at a time, instead of frames, then you'll want a singleton driven system update. Otherwise, consider those approaches in the forum post.

gilded glacier
#

thanks for the link, maybe I'll return later if I won't find the answer, or when my brain comes up with another petty problem

viral sonnet
#

you have started with one of the more complicated questions to solve 😄

robust scaffold
#

Ugh, i think im gonna stick with singlethreaded BVH building. It's about 1ms slower for 10,000 entities (3ms total) and it gets worse from there compared to unity's parallel BVH builder but mine works and I dont want to debug why my copy pasted Unity's version doesnt.

robust scaffold
#

With burst:

unknown.png
#

Without burst

unknown.png
#

well fuck

viral sonnet
#

huh, why is that different?

robust scaffold
#

Yep

viral sonnet
#

so i've made a performance test now. getting the targetInfo from a local comp or in a cached pointer when the comp is on a foreign entity. surprisingly the difference is hardly measurable. i run with a sampe size of 500 and it fluctuates a little. in a blind test i wouldn't be able to say what's what

#

usually this is a lot more but i think because the entity and its reference are created at the same point, they are aligned quite well

#

snd i have no idea if the cpu anticipates jumps with the same offset

rustic rain
rustic rain
#

For systems with single action

#

You can actually just use stream

#

For super fast iteration

#

And avoid any structural changes

#

The only question would be how to get that native stream reference

viral sonnet
# 
spellcast with ptr ~2.74-2.78ms``` found it odd to have different timings than my tests i did some time ago. turned out my editor was already at 13gb 😄 now the tests are much more than what i expected
#

and @robust scaffold that's what i meant with trade offs. the rpg data layout lives in a whole different world of complexity. it's gain some, lose some and pick the option where you lose less. the targeting system had an ugly rat tail of data. just yesterday i gained 1ms in 1 job but lost more than that in another because of it 😄

robust scaffold
viral sonnet
#

uhm, no. maybe 😄 the editor ran for 3 days or smth

balmy thistle
viral sonnet
#

oh that reminds me of the pipe dream FloatMode.Deterministic: Reserved for future, when Burst will provide support for deterministic mode

rotund token
#

Will you really enjoy the performance cost

robust scaffold
#

The differences I posted is because I did a dumb and off by one error

viral sonnet
robust scaffold
#

Well, unity physics has no FloatMode.Deterministic tags (yet) so maybe?

#

They advertise it as cross (PC) platform deterministic already so it's probably not needed for now

timber ivy
#

im trying to load/unload subscenes by adding components, I got some reference code from @rotund token but am unable to get it working. Anyone see where I went wrong?

when the game enters play mode the first thing that happens is all subscenes are loaded but not opened.

 foreach (var pair in streamingManager.worldGrid)
        {
            var e = sceneSystem.LoadSceneAsync(pair.Value, new SceneSystem.LoadParameters()
            {
                AutoLoad = false,
                Flags = SceneLoadFlags.LoadAsGOScene | SceneLoadFlags.DisableAutoLoad
            });


        }
#

Then later I attempt to actually open the subscenes up so they will be visible in the game but it does not do anything.


        Entities.WithAll<ResolvedSectionEntity, CellComponent>().ForEach((Entity e, int entityInQueryIndex, ref CellComponent cell) =>
        {
           
            var bufferHolder = GetBufferFromEntity<ResolvedSectionEntity>();

            var has = bufferHolder.TryGetBuffer(e, out DynamicBuffer<ResolvedSectionEntity> buffer);
            if(has == false)
            {
                Debug.LogError("No buffer on entity");
                return;
            }
  

            if (IsChunkRelevant(currentCell, ref cell) == true)
            {
                ecb.AddComponent<RequestSceneLoaded>(entityInQueryIndex, e);
                ecb.SetComponent<RequestSceneLoaded>(entityInQueryIndex, e, new RequestSceneLoaded()
                {
                    LoadFlags = SceneLoadFlags.NewInstance | SceneLoadFlags.LoadAsGOScene
                });
                foreach (var section in buffer.AsNativeArray())
                {
                    ecb.AddComponent<RequestSceneLoaded>(entityInQueryIndex, section.SectionEntity);
                    ecb.SetComponent<RequestSceneLoaded>(entityInQueryIndex, section.SectionEntity, new RequestSceneLoaded()
                    {
                        LoadFlags = SceneLoadFlags.NewInstance | SceneLoadFlags.LoadAsGOScene
                    });
                }
                
            }

        }).Schedule();

is there a component I am forgetting to add or something?

#

Its adding the components in the foreach loop but adding the components isn't loading the scene x.x

robust scaffold
#

Finally fucking nailed down why my math wasnt working. NAN propagation from a -INF multiplication by 0.

agile cradle
#

Hi there. How can I prevent specific monobehs from adding to entity in "ConvertAndInjectGameObject" mode?

balmy thistle
timber ivy
#

Ok so what do I do if I need to add a component that unity created but has defined as internal?

viral sonnet
viral sonnet
timber ivy
#

which is defined as internal so I am unable to use it

#

is dots source posted anywhere so I can edit it?

balmy thistle
#

various packages are in Library/PackageCache

#

if you want to edit you'll need to copy it out of there and edit your manifest to point to it using file local scoping

timber ivy
#

is there somewhere I can request this to be made available to us so I dont have to edit this file everytime ecs updates?

balmy thistle
#

you mean, just have the source code posted somewhere?

rotund token
rotund token
#

Unless you already solved it

viral sonnet
#

we use the asmref trick btw. to have access to internal stuff

timber ivy
# rotund token Unless you already solved it

I think I may have. In order to get the scene to load with LoadSubSceneAsync I have to use the loadasgo loadflag. Which means I need to also add a RequestGameObjectSceneLoaded component to the scene entity

rotund token
#

Ah hmm not sure about that flag

timber ivy
#

I am not even sure why I have to use it

#

I have a subscene with plane in it

#

it should just be converted to an entity shouldnt it?

viral sonnet
#

it's certainly getting harder to argue why I split the entities

unknown.png
#

this is with 0 code changes but just less chunk capacity

agile cradle
viral sonnet
#

animations will be a bit painful. as there's no dots animations we still have to rely on gameobjects. fortunately hybrid components are helping out with this

#

what that means is that you can put an animator component on an entity

timber ivy
#

You can also bake the animations to a texture and use a shader to play them

robust scaffold
robust scaffold
agile cradle
viral sonnet
#

try to split the object in what you need as MB and what you need as entity. then you can use subscenes and needn't worry about how it converts. you can easily link them then

#

best thing to do is that the entity has full control and spawns the GO/prefab.

#

the way I see it, is that the Go is just the visual representation

#

and beware of subscenes. MBs you put on GOs in a subscene will work fine in editor but won't in a build

agile cradle
viral sonnet
#

not necessarily, 1 system can handle this

timber ivy
#

Do I have to do anything special to get the objects in my subscenes to convert to entities?

viral sonnet
#

nope, just put them in there. you can see the converted entity in the entity hierarchy

rotund token
#

you do have hybrid renderer in your project right

#

and using urp or hdrp

timber ivy
#

yes I do

#

they are rendering if i manually load them

#

with the buttons in the editor

#

but if I loadsubsceneasync and dont use the LoadAsGOScene flag it wont work

timber ivy
viral sonnet
#

window -> dots -> hierarchy

timber ivy
#

Yeah I am there

#

would plane be the entity its making?

#

or the original game object?

viral sonnet
#

the entity, if you click on it the inspector shows you the comps

#

the go will be gone

#

it's just for authoring in the editor

timber ivy
#

Ok I see the problem its not auto adding any rendering components

#

wtf

viral sonnet
#

that should work. what are you using on the GO?

timber ivy
#

just a regular plane but reimporting hybrid renderer is what I am trying first

viral sonnet
#

i don't think reimporting changes much but try your luck 🙂

#

so how does the converted entity look?

timber ivy
#

Idk i guess I had wrong version of hybrid renderer installed or something cause uninstalling and then installing 0.51 made it work

#

now it gets converted and renders

#

and loads without the loadasgo flag

#

yep everything working now lmao

#

stupid editor bugs kill me everytime x(

#

is it fine to just remove a component without checking if it first has one?

timber ivy
#

is there a way to read from a dynamic buffer on an entity in entities.foreach().ScheduleParralel?

viral sonnet
#

yes, with [NativeDisableParallelForRestriction] tag on it

#

hm, i'm really not too sure where this started that a high chunk capacity is so important. it is maybe for simd jobs but in non-simd it seems to hardly matter

viral sonnet
timber ivy
#

thank you

viral sonnet
#

i was thinking of something different earlier, the tag I was mentioning is when you want to lookup and write to buffers from other entities via GetBufferFromEntity.

timber ivy
#

Do dots colliders interact with gameobject colliders?

devout prairie
#

nah

timber ivy
#

So you can't load your world via subscenes then spawn in a monobehavior vehicle to drive on the colliders generated? rip :/

devout prairie
#

nah, not without converting the vehicle colliders/bodies to dots

timber ivy
#

Will the physics behave mostly the same if I do that?

devout prairie
#

uhhhhhhhmmmmmmmm

#

most likely not by default

#

most vehicle prefabs will have scripts that apply physics torque etc etc so that won't work off the bat, without converting to dots systems

#

the basic colliders, joints and rigidbodies may or may not convert to something similar though

#

i doubt unity.physics conversion has a conversion from unity wheel collider etc tho

timber ivy
#

I dont use wheel colliders

#

I use raycasts

#

but yeah what I am asking is

#

if the addforce/addtorque calls will result in the same behavior from the body they are applied to

#

like if I add a force at a point on a cube with built in physics then add a force, will I get wildly different results if I do the same thing in dots physics?

devout prairie
#

in theory it should be similar but in practice it tends to be different especially once you introduce joints

timber ivy
#

I am not using joints either so that helps

devout prairie
#

there is a vehicles example in the physics sample though

devout prairie
timber ivy
#

Raycast suspension, basically i shoot a raycast from the top of the wheel hub on the car downwards and apply some math to find wheel position from there then add force upwards from the ground to raycast start point

#

then I apply all my friction logic

devout prairie
#

how do you then make the wheel follow the car body without a joint

timber ivy
#

you mean the mesh?

#

i just manually set the mesh position each frame

devout prairie
#

ah so the wheel isn't a rigidbody

timber ivy
#

no

devout prairie
#

just the main car body

timber ivy
#

just the car itself

#

the only downside to this is you have to calculate wheel friction yourself

devout prairie
#

right yeah

#

you should be able to convert that to a dots setup i think

timber ivy
#

I think so too, just hoping the feel of the cars dont change too much

devout prairie
#

what i've found with joint setups is it's possible to achieve similar results it just take s lot of tweaking

#

i think in your case it should be simpler, less tweaking as you just have the car body, might work right off the bat

timber ivy
rotund token
#

but all you need to do is add the component by the same name

#

note that Issue was right and you always need to have section 0 open

#

and sections can't reference each other

#

except every section can reference section 0

timber ivy
#

my idea was to create a vehicles subscene and load/unload the ones I need by section at runtime. Then I could reuse the same system that is loading/unloading the world to stream in assets in and out as needed

viral sonnet
#

haha, so i've merged everything now. my main caster archetype, physics (ltw/trans/rot) and even stats. it's not slower on the main jobs and some jobs don't even need to run now or are a bit faster because of less random access. chunk capacity is at 32 now

devout prairie
#

or you mean those were separate entities before

viral sonnet
#

yeah seperate entities

#

so yeah, it hardly matters how big the chunk capacity is. i mean, it shouldn't be <16 or smth but even then. probably there are reasons when an entity is so big and splitting has quite a few downsides with questionable gains. a factor would be that the whole intro of an Execute chunk path gets called more often with less chunk capacity. those are mostly in the <1ms range. shouldn't matter too much.

robust scaffold
#

To get really micro-optimizing, think: do you really need full float precision? You can pack 2 halves in 1 float. That's double the numbers for the same space. If you just need a general value, consider cutting down to normalized bytes. That's 4 numbers in one 32 bit float. Although at that level, you have to check the PCs you're targeting as some of the newer ones dont have advanced mathematic operations for vectorized bytes like division.

#

Check out some of the fancy shaders on shaderlab. They can get really creative on the bit precision of floats to squeeze as much data throughput during the CPU - GPU transfer. Every bit counts.

rotund token
#

well half is really only useful for tiny numbers

#

like 0-1

robust scaffold
# rotund token like 0-1

That's Unorms (byte floats). Half is pretty decent for good enough numbers. About 6 digits of precision closest to 0.

#

Math comes with a handy conversion to half precision as well: math.f32tof16() and the reverse of it as well.

limber basalt
#

is the burst compiler just for jobs/DOTS stuff? i've just started using 2021 after being dedicated to 2019, and the URP template comes with burst, not allowing me to remove it since it's a dependency.
i would like to remove it if i can, but i'm not sure what packages depend on it?

timber ivy
limber basalt
viral sonnet
timber ivy
#

what do you mean?

viral sonnet
#

these 2 physic systems don't collide with each other. so the conclusion is the monobehaviour gets converted to an entity with dots physics colliders

timber ivy
#

nah im just dumb apparently the check box in the hiarechy means the subscene is loaded as a gameobject scene and not just that its loaded

#

so ofc it was colliding

robust scaffold
robust scaffold
robust scaffold
viral sonnet
#

removing burst is pure blasphemy!

balmy thistle
limber basalt
#

i figured it wouldn't be core because it's in the package manager, which implies it's opt-in?

#

they even have a built-in section in the package manager for stuff which is assumed to be included in every project

viral sonnet
#

afaik it's built in now. but you can update it

robust scaffold
viral sonnet
#

same as urp or hdrp and so on

narrow field
#

Is it possible to update a compute buffer in parallel using DOTS/Jobs?
I'm making a clone of the gmod LIDAR thingy in Unity and currently my main performance bottle neck is updating the buffer that contains the points for the dots that appear when raycasting on the environment
Rendering performance is fine even with millions of points maximum, but the CPU grinds to 60 FPS (from 1000+) and below when having to update the buffer

limber basalt
#

is there any way to remove the jobs menu at the top of the editor at least?

robust scaffold
robust scaffold
timber ivy
robust scaffold
timber ivy
#

last i checked urp templates didn't depend on jobs or burst but idk

robust scaffold
viral sonnet
#

how do you use f32tof16? it returns a uint which is still 32 bits?

timber ivy
#

half value = (half)f32to16

robust scaffold
viral sonnet
#

ah i see, thanks

robust scaffold
#

It mirrors HLSL shader code, which does not have a ushort equivalent. Only uint. So you can just << 15 and stick in another half into the empty space.

narrow field
#

probably a dumb question, but is it possible to just have the Job System without having ECS etc or are they hard dependencies?

timber ivy
#

you can have just jobs

robust scaffold
viral sonnet
#

does setting the internal buffer capacity of a DB only works with the tag or from code too?

rotund token
#

tag

# 
if (capacityAttribute != null)
    bufferCapacity = capacityAttribute.Capacity;
else
    bufferCapacity = DefaultBufferCapacityNumerator / elementSize; // Rather than 2*cachelinesize, to make it cross platform deterministic```
TypeManager needs to set it up during initialization
#

in theory you might be able to reflect into type manager

#

edit the s_TypeInfos array

#

and adjust the capacity after it initializes

#

and before anything else is loaded

viral sonnet
#

hm too complicated ^^ guess i'll stick to a code gened constant

robust scaffold
#

Hrm, i dont know if I'm reading the source of rewindable allocator but I think it clears before returning a new NativeArray.

#

the Block block = default; I think indicates that the block memory is being cleared.

timber ivy
#

Is there a way to create an entity that is a copy of another?

#

I found EntityManager.CopyEntities but seems overkill for just one entity

robust scaffold
#

If you want to copy some components and not others, you need to make a custom instantiate.

timber ivy
#

awesome

#

thank you

timber ivy
robust scaffold
timber ivy
#

Alright cool.

rustic rain
#

If your entity is fully unmanaged instantiate will be as fast as memory copy

timber ivy
rustic rain
#

Managed components

timber ivy
#

ok

rustic rain
#

Like sprite renderer

timber ivy
#

what about 3d renderer?

rustic rain
#

It's good

#

Shared comoibents

timber ivy
#

so its unmanaged then?

rustic rain
#

Which is RenderMesh

#

Are stored outside of chunks

#

In special list

timber ivy
#

ah

rustic rain
#

Idk about managed comoinents

#

And hybrid specifically

#

Which are sprite renderers and companion links

#

Maybe internally Unity pools them somehow

#

Maybe not

#

But since it's usually naked spirte renderer

#

I'd guess it's not nearly as bad as normal go instantiate

robust scaffold
#

Today's 7 hour debugging session lesson: Safety provided by native arrays is actually good.

winged bane
upper tiger
#

Hi All, if I store a reference to an entity and that entity then changes version after a structural change does my reference also change or does it not refer to something that doesnt exist?

rotund token
#

Entities can't change version

#

Structural changes don't cause entity version to change

#

The version only bumps when an index is reused when creating a new entity

upper tiger
#

So if I spawn an entity and store a reference to the entity somewhere then make a structural change by adding a new component to that entity, does the reference still point to the same thing?

# 
Entity a;
Entity newEnt = entityManager.Instantiate(prefab);
a = newEnt;
entityManager.AddComponent<NewComponent>(newEnt);
Debug.Log(newEnt);
Debug.Log(a);
#

do these print the same thing?

rustic rain
#

beware, doesn't work with buffer

#

instantiate entity in ECB will be index of -1

upper tiger
#

yeah I've come across that already

rustic rain
#

SetComponent fixes it

upper tiger
#

So if I store references to Entities, they will always point to the same valid entity unless I call Destroy() on that entity at some point in time

rustic rain
#

yes

upper tiger
#

Also do those entity references work properly if I serialise my game for save/load

rustic rain
#

no

#

you need remapping

#

for save load

#

kek

upper tiger
#

can i worry about that part later or does the way remapping works mean I have to change the structure of how I store data now

rustic rain
#

well, from what I see

#

save load means you fully serialize your game state

#

meaning if it's done on hard reset

#

you'll have to recreate all entities

#

but they will be different

#

in order to fix it you's need to remap them

#

so if old entity index is 1:1

#

and new entity is 2:2

#

you'll have to go through all component data of freshly deserialized world

#

and look for all entitiy fields

#

remap it from old values to new

upper tiger
#

sure, but how do you know what Entity values point to which entities

rustic rain
#

when you save game

upper tiger
#

you have 5 references to entities and 20 entities

#

which is which

rustic rain
#

you save entitity indices to which saved data they correspond

#

once you started loading

#

every time you create new entity with that data you want

#

you make a hashmap

#

Entity:Entity

#

so now you have serialized data, new game state and hashmap

upper tiger
#

oh so when you serialise, you iterate through the serialised data and hashmap it

#

and then just remap after

rustic rain
#

at this point you simply go through all entity fields, read current value, find it by key in hashmap, write new value

#

yeah

upper tiger
#

sweet

rustic rain
#

ComponentType has a field HasEntityReference or smth similiar

upper tiger
#

so as long as I am keeping things clean ECS then it should be a worry later problem

rustic rain
#

afaik you'll have to remap using memcpy

#

or smth similiar

#

not sure

upper tiger
#

yeah thats all good, I just dont want to have to rework everything to make saving possible

#

Thanks for the advice!

timber ivy
#

lets say i have 50 vehicles but only 3 of them are unique. it makes no sense to have data like gear ratios baseTorque etc on a component attached to each entity. Normally I use scriptable objects for this but they dont pair nicely with jobs. Anyone have any other suggestions?

rotund token
#

Kind of what blob assets are for

winged bane
#

its not the end of the world if you do replicate some of the data, ECS isnt a relational database after all, but blob assets is a good suggestion

rotund token
#

Oh totally agree. In general I'd just dump it on components

#

More flexible in future

timber ivy
#

If you're manually setting a section of a subscene it appears you must set 0 first to something

rotund token
#

0 must always exist and be loaded

timber ivy
#

er maybe I am just doing it incorrectly actually

# 
public class VehicleAuthoring : MonoBehaviour, IConvertGameObjectToEntity
{
    [SerializeField]
    internal int id;
    public void Convert(Entity entity, EntityManager dstManager, GameObjectConversionSystem conversionSystem)
    {
        var oldSection = dstManager.GetSharedComponentData<SceneSection>(entity);
        var sceneSection = new SceneSection() { SceneGUID = oldSection.SceneGUID, Section = id };       
        dstManager.SetSharedComponentData(entity, sceneSection);
    }

}
#

i have this attached to 2 game objects in a subscene

#

id is set to 1 to 2

#

but the entities are set to section 0 still

#

creating an empty gameobject that is manually set to section 0 does not fix this problem either

#

actually I think the problem is because they both use the same material

#

so its loading both of them to 0

rustic rain
#

am I the only experience constant problems with subscene import in 21.3.7f?

devout prairie
#

God any time i try to use subscenes i get issues

#

Any idea what this is:

unknown.png
#

The console that normally appears on the subscene mono seems to have vanished also, it was there before:

unknown.png
#

Where it normally has buttons for load etc

timber ivy
devout prairie
timber ivy
#

did you put any objects in it?

#

might explain why there is no load/unload buttons

rotund token
rustic rain
#

which make subscene invalid

#

sometimes it's solved by clearing cache

#

sometimes by restarting editor

rotund token
rustic rain
#

just installed 8f, seems to also fix it

#

no idea for how long

devout prairie
#

funny i just noticed your comment issue, seems maybe same as mine

#

i'm on 2020.3.34f1 tho

#

Clear entities cache seems to have helped:

unknown.png
#

Brought the log back etc

#

Really, REALLY annoying how these issues seem to plague the whole subscene/conversion thing

timber ivy
devout prairie
#

How you guys store blobs created inside subscenes, so that they can be referenced later?

#

I think the docs suggest adding refs to them to components, is there another way

rotund token
#

How else would you access them?

devout prairie
#

Previously i was just creating them during mono/Convert ( ie not in a subscene ) and then storing the reference as a member of a system

#

like this basically

rustic rain
#

hmmm, is modification of companion link supposed to work?

            var spriteRenderer = EntityManager.GetComponentObject<SpriteRenderer>(player);
            _mat = spriteRenderer.material;
            spriteRenderer.material = _mat;
#

I tried this

#

but it's still using default shared material

timber ivy
devout prairie
#

I take it this is more the intended usage:

unknown.png
timber ivy
#

interesting i wasn't aware this was a feature

devout prairie
#

I'm finding that my subscene+blob isn't being loaded in until after my spawner systems OnCreate method.. is the best approach to use [DisableAutoCreation] on Systems and then create/add them to the world manually to ensure correct ordering of things?

rotund token
#

subscenes load async

#

they will never be loaded before OnCreate

#

because the scene system has to update to load the subscene

#

my personal approach is to create world/systems, disable simulation update, load needed subscenes for config, wait for subscenes to load, enable simulation update

#

systems can now access the config

#

my systems do no need the config in oncreate though

#

i might have a always update system use onstartrunning for the rare cases it did need to init something

#

but yes the alternative is to

#

create world, add subscene systems

#

load subscene

#

load your systems

devout prairie
#

hmm, thanks for the info

#

i am getting an error when i try and cache my blob inside OnCreate, saying zero singletons exist

#

but when i do it in OnUpdate it's finding it

#

maybe it's the component itself that is not yet created, rather than the blob 😐

rotund token
#

yeah because world created, oncreate run, subscenes load, start updating

devout prairie
#

ah right ok i just reread your first two lines above

#

god damnit this is annoying 😛

#

ok i'll just grab it in OnUpdate and deal with that later

#

it's another layer of complexity i don't really need at this point

rustic rain
#

what kind of info do you need

devout prairie
#

only used for spawning anyway

rustic rain
#

that it is hidden in subscene

#

and should be used in oncreate?

devout prairie
#

Well i figured, i'll try and switch over to subscenes, as really it's what DOTS expects

rustic rain
#

well yeah, but not for literally everything

#

some things can be simply loaded as GameObject in a scene

#

or component to subsene GO

devout prairie
#

So i dumped my objects which convert and register prefabs ( and build blobs with prefab and init data ) into a subscene

rustic rain
#

oh prefabs

#

I store prefabs on entitites

#

and I don't save them on systems

#

I always keep them on entities

devout prairie
#

well it's swings and roundabouts i think

rustic rain
# 
            Entities.WithReadOnly(ltws)
                .ForEach((Entity entity, ref Spawner spawner, ref LastSpawned ls,
                    in DynamicBuffer<PrefabElement> prefabs,
                    in LocalToWorld ltw) =>
                {
#

here's how my spawning system looks like

devout prairie
#

i'm building blobs from scriptableobjects, so that when i'm spawning a unit i can pull the prefab entity and any init data such as health, weapon, etc etc etc

rustic rain
#

but why store entities in blobs

#

besides

#

you should probably create blob in covnersion in this case

devout prairie
#

well an entity is just a struct, it's just a key really

rustic rain
#

instead of runtime

devout prairie
#

i am creating it in conversion

#

previously gameobject conversion but now trying it with subscene conversion

rustic rain
#

shouldn't be any different

devout prairie
#

indeed, indeed

#

throws self off cliff

rustic rain
#

I just don't get why you'd need reference to smth in OnCreate

devout prairie
#

well..

#

i thought, i'll grab the singleton component that has the blobassetreference, and cache its blob ref to the system, during oncreate

#

then i don't need to look for it any time the spawner system updates

rustic rain
#

hmm, I have similiar problem, but it's a bit different

#

I have a large amount of prefabs

#

which I need to store as prefabs

#

and then keep somewhere a database with map to those prefabs by string

#

and so I figured I could make an additional entity

devout prairie
#

yeah similar idea i think

rustic rain
#

during conversion

#

which will be picked up by some Initialization system

#

and this additional entity will keep reference to prefab

#

which will be a way to register your prefabs

#

in your blob

devout prairie
#

yeah

#

so i have a click to spawn unit right

#

currently, just for simplicity, you click, and it creates a 'spawn' entity with a component holding the string name of the unit to spawn ( previously i used a unique id but i'm simplifying this atm )

#

the spawner system then see's there is a 'spawn' component and runs

#

the spawner system has a cached reference to the blob holding all the prefab data..

rustic rain
#

yeah, I might use similiar approach

#

by saving blob asset with FixedString

devout prairie
#

it then uses the string name to pull ( from the blob data ) the prefab entity to instantiate, as well as any init data

#

so that's the idea

rustic rain
#

and then keeping blob asset reference on entity

#

to keep track of which prefab it was created from

#

for save/load

#

or spawning

#

or grabbing some kind of data from prefab

devout prairie
#

yeah it's just a way of basically having a similar system to scriptable objects that are so common in the mono environment

#

so you can have say ScriptableUnit, with a bunch of data about that unit

#

and you spawn the unit and apply all that data

#

but instead, in dots, converting those ScriptableUnits into blob assets so that they can be referenced by the spawner system

rustic rain
#

hmm

#

Is there any reason why entity would "stutter"?

#

It is dynamic but with PhysicsMassOverride to Kinematic

#

I change it's Translation

#

and on high speed stuttering is very noticable

viral sonnet
#

high speed? simulation frame time too low/inconsistent?

rustic rain
viral sonnet
#

but that's not the simulation frame time is it?

rustic rain
#

I update translation on frame update

viral sonnet
#

well that's no good when you want stable movement

#

you'd need a consistent 1/110 ms

rustic rain
#

I use time delta obviously

#

but it stutters as if I used physics velocity

viral sonnet
#

take a screenshot if the timeline

rustic rain
viral sonnet
#

this is what i mean

unknown.png
#

it has to be a totally flat plateau otherwise you will see stutter. the brain is exceptional at picking those up

rustic rain
#

I don't get how it is relevant

#

_curMov.Value -= new float2(0.5f, 9.81f) * state.Time.DeltaTime;

#

this is how I manage my virtual velocity

#

and then

viral sonnet
#

DeltaTime is sometimes higher and sometimes lower.

rustic rain
# 
            var em = state.EntityManager;
            var tran = em.GetComponentData<Translation>(_player);

            var deltaMov = _curMov.Value.y * state.Time.DeltaTime;

            tran.Value.y += deltaMov;
            em.SetComponentData(_player, tran);
viral sonnet
#

it only moves consistent over time

#

physics ticks and simulation frame rates exist for a reason

rustic rain
#

but delta time exactly compensates for frame drops

#

I have used this approach hundreds times

#

and only now

#

it appears to stutter

viral sonnet
#

i don't know what to say other than no, this is not how you'd do it. usually you split physic moves and interpolate to the current frame

devout prairie
#

think possibly because it's a kinematic physics body it would require fixedDeltaTime

viral sonnet
#

this is the only way to got linear movement

rustic rain
#

all I really want is for it to update

#

every fixed step

#

collider position

viral sonnet
#

there's an old article that explains this pretty well. i see if i find it

devout prairie
#

yeahhh, i think though possibly physics is interpreting what you change the translation value to during its fixedstep, whereas you're actually setting that value using delta

#

so it's kindof a clash of two intervals

#

i could be wrong though, but i'd give fixedDeltaTime a whack

rustic rain
#

physics shouldn't modify translation at all

#

velocity is 0

#

body is kinematic

viral sonnet
#

you move an object with velocity -> physics. if you use dots physics for it is not relevant

devout prairie
#

yeah i'm just guessing that although it's kinematic, it's still trying to interpolate in some way

rustic rain
viral sonnet
#

i know, still physics 😄

rustic rain
#

and it worked

#

4 times

#

in this exact purpose

#

on 5th it doesn't

#

only difference

#

body is dynamic

#

with override

viral sonnet
#

can you test with a body that's not dynamic?

#

i'm not aware of any interpolation stuff going on

#

hm, no there's a smoothing option so just being dynamic can't really do something. why is it dynamic unlike the others?

#

possible cause of problems could also be that you change the translation by hand. that interferes with a dynamic physics object

#

best would be to use velocity then

rustic rain
#

welp

#

guess what

#

changed to static

#

no stuttering

#

kinematic stutters

#

dynamic without physics mass override stutters too

viral sonnet
#

on static, physics doesn't do anything so setting the translation is okay. on every other option you want to set velocity. try it out. should be easy enough

#

and also give the interpolation a try then

rustic rain
#

I can't use velocity

#

because I need high fps translation updates

#

and velocity smoothing are dogshit

#

for my use case

#

bruh

#

at least I have backup plan

#

I assign collider to different entity which will be copied to main player entitiy

#

so I won't care about it's stuttering

#

but then I need it vice versa

#

because once player hits ground, I need it to be dynamic

#

oof

#

but I still don't understand why it happens

#

physics are supposed to be stateless

devout prairie
#

gave up trying to use subscene conversion with prefabs, it's just a complete pain in the ass

#

i've got one prefab that works fine i can grab the GetPrimaryEntity during conversion and store that in a blob

#

aaaaand another prefab that inexplicably doesn't work

#

just too much of a hassle

rustic rain
#

why are you trying to put all prefabs in one blob

#

here's how my system like this works:

#

I create some object in subscene

#

and make authoring component with GameObject[] field

#

where I assign all prefabs

#

then I reference them

#

and then in conversion I create for each object a blob with string identifier for it

#

it's double FixedString128