#skein

4394 messages · Page 5 of 5 (latest)

polar trout
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sure, if its new enough to have bevy_remote to communicate with bevy app and fetch component registry(or however its called)

modest lynx
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I did but I don't know I get this message

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so what I miss

modest lynx
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{"jsonrpc":"2.0","id":null,"error":{"code":-32600,"message":"EOF while parsing a value at line 1 column 0"}}

snow heron
modest lynx
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yes indeed

snow heron
modest lynx
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I followed the instruction 😄

snow heron
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are you running your application in --release mode

modest lynx
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cargo run -r

snow heron
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don't do that

modest lynx
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cargo run

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I will try it

snow heron
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BRP is disabled when building for production, because it is not typically required.

modest lynx
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could please told me what is the purpose behind. could I see the whole scene in blender when they are connected?

snow heron
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BRP (the Bevy Remote Protocol) exposes information about your program via http endpoints. One of those is the type registry, which includes information about all of the components you've defined across all of your own code and any dependencies you've installed. The type registry information is used to build forms for component data in blender.

modest lynx
snow heron
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once you fetch the data, it is stored in the .blend file as json. So you can use blender with the component data without the bevy application running

snow heron
# modest lynx

ok, its time for you to give more details about what you did, what versions of everything you're using, etc

modest lynx
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I will

snow heron
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you're using an older version of blender there (4.2) instead of the most recent release (v5)

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are you on a recent version of bevy?

modest lynx
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4.2

# 
    App::new()
        .add_plugins(DefaultPlugins)
        .add_plugins(SkeinPlugin::default())
        .add_plugins(EguiPlugin::default())
        .add_plugins(WorldInspectorPlugin::new())
        .add_plugins(GamePlugin)
        .register_type::<Player>()
        .run();
}```
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it doesn't work in 4.2?

snow heron
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it should, as far as I know. but I haven't tested it since I switched to v5. That doesn't look like a blender error to me, that looks like an issue with the data coming back from bevy

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you haven't shared the bevy version you're using yet though

modest lynx
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yes because

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of this {"jsonrpc":"2.0","id":null,"error":{"code":-32600,"message":"EOF while parsing a value at line 1 column 0"}}

snow heron
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what bevy version are you using

modest lynx
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0.18

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this what chatgpt tell me

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If the registry has no registered types, Blender receives empty JSON, which produces exactly your error:

snow heron
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I am not interested in debugging chatgpt output

modest lynx
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ok

snow heron
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I have confirmed that skein works on windows with bevy 0.18 so it must be a local configuration issue. However I can not help you with chatgpt generated output so you'll have to figure out what went wrong on your own.

modest lynx
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I will figure out thank you

polar trout
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holy motherboard🤖

modest lynx
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holy cow

ocean burrow
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I assume not

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but if reflect_auto_register happened to be disabled, that could maybe be it?

modest lynx
ocean burrow
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Just make sure your Cargo.toml does not contain default-features = false

modest lynx
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I will thanks man🙏

hexed yarrow
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I use bevy_skein pretty extensively in my game. after refactoring, the fully qualified paths to components often don't match anymore, after re-fetching the bevy types. is there a way to find incompatible or non-existing components after a fetch, directly in blender?

snow heron
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the real solution is to separate code location and type_path though

# 
#[derive(Component, Reflect, Debug)]
#[reflect(Component)]
#[type_path = "api"]
struct Character {
    name: String,
}
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if you had used this, for example, the source code location would not matter

hexed yarrow
snow heron
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yeah I wish I had more time to invest into refactoring tools, but the core issue is preventable at least

hexed yarrow
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yep, I'm totally fine with that solution. it really happened to me like 8-10 times that something didn't work because the component was missing at runtime. I already knew what was causing it, but when you use the feature extensively, it's really a lot of work to update the components in blender after big refactorings. but with type_path and the migration tool that's really great

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one small improvement I can think of: marking or highlighting unresolved components directly in blender in red. it's kind of redundant with the migration tool, but that way you can see right away in blender what's going on

snow heron
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I'm not opposed to better visualizations in blender. Its just a matter of how

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if you say, break all of the component paths, then fetch the new registry data, we don't have the old registry to check against.

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its very similar to doing database upgrades. If you rename a column, the old column is gone and sql queries that expect it won't work

hexed yarrow
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yeah I understand. you don't know the new fqn, but after the fetch you at least know that the existing one doesn't match. you can't fix it through the ui/blender, but you can see that something's off. the actual correction can then properly happen through the migration

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but maybe that feature is redundant. if someone is at the point where they're loading the blender file and looking at the skein components, they probably already know that something's off. not sure about it

snow heron
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yep, and there's some additional difficulty because blender requires us to define types for the values. So what we actually end up with for the UI is something like this (in rust pseudo-code)

enum Components { Every, Possible, Component }
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which means, the ui is driven by the data. If the data is incorrect, we don't even know the data is supposed to be there

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so it'll have to be some kind of "on registry fetch, re-validate all data" sort of approach I think

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maybe just "collect all type_paths and check to see if they exist in the new registry"

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in any case, I'm very open to options and more thoughts if people have them

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the cli tools are just a precursor to in-blender migration tools too, so definitely thinking about it

hexed yarrow
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oh ok, yeah. but I think my original question is mostly answered, with type_path and the migration tool. at least I won't have any more headaches with that. in my current game state, a lot of things are either asset-driven or done directly in blender with skein. right now I'm still implementing everything I need. but soon I want to build a vertical slice to see if the game concept holds up or what I need to change. there are a lot of components: avian, trigger areas, spawn points, etc. that's where it would get ugly if I had to do it all by hand

snow heron
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yeah, we unfortunately can't control third party dependencies doing refactors and such. So the migration/checking/etc stuff is still important

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there's also people who want to still productively work when constantly breaking type paths and such, sort of as a working style preference.

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and I view skein more like infrastructure, so if we can support that better without bending over backwards we should

hexed yarrow
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do you plan to keep maintaining skein after the editor is introduced? I could imagine that the bevy editor would be able to do that (depending on scope). as of today, skein is the best there is. but I could also imagine that it would be easy in the bevy editor to load an asset (like glb) and then attach components "natively"

snow heron
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I do, yes

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I think it will still be useful in a world with an editor (and the editor will take awhile to materialize anyway)

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plus I plan to break ground on a blender -> bsn exporter. So tbd where that goes

hexed yarrow
ocean burrow
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@snow heron I'm running into an issue where I would really like to have modifiers applied before exporting my stuff, but would prefer to not have to apply them destructively in-editor. I remember you forked the Blender glTF exporter, but I forgot if you fixed this particular issue upstream

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well I guess I can do

  • A
  • Ctrl-A
  • Visual Geometry to Mesh (AKA apply all modifiers)
  • Export
  • Ctrl-Z
snow heron
ocean burrow
ocean burrow
#

@snow heron while working on an own little addon I ran into two papercuts with Skein, so I PRd you the fixes 🙂

snow heron
ocean burrow
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@snow heron do you have a tip on how to read Skein-authored components from another Blender addon?

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specifically, what I'm trying to do is enumerate over all objects in the scene and select the ones that have a certain marker component

snow heron
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the data will still be there, and be accessible, so you'll want to turn on the blender dev tools that show you data paths.

ocean burrow
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I didn't consider that that would work on non-builtin stuff too

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ofc it does

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it just didn't occur to me 😄

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I see, it's active_component_index

snow heron
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active_component_index is just the currently displayed component in the ui

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you have to keep the "current item" and the "array of data" separately in blender, so we have to stick the active_component_index on another type

ocean burrow
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oh okay

snow heron
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you should see something like skein_two[n].morestuff

ocean burrow
snow heron
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right, so you're hovering over the list there, and thus seeing the data that you're hovering over, which is the active index

ocean burrow
snow heron
ocean burrow
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thanks!

snow heron
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In terms of data organization, the blender PropertyGroups stuff means that there's a PropertyGroup called a ComponentContainer . that is basically a giant object where all field names are component paths, and the values are null for all keys that aren't the selected component for the thing at skein_two[n].

ocean burrow
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perfect! heart_lime

image.png
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that did the trick, thanks 🙂

snow heron
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if the marker component path exists in skein_two[n].selected_type_path, then it is the mark-- yeah that

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perfect

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If you continue this we could make apis instead of making you muck with the data internals, but I assume this is Good Enough for you at the moment

ocean burrow
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definitely Good Enough, that is

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Ah btw no rush on the modifiers thing

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the addon I'm tinkering with is a personal export automation tool

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where I'm now manually applying all modifiers before the glTF export begins

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that way I can now work around the upstream bug broovy

snow heron
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ok cool 👍 as long as you have something that's working for you

tidal tartan
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I'm having issues where some models won't show up in bevy. They exist, but are just invisible for some reason. What should I look at to debug why this is happening? I'm guessing it's some kind of material issue.

snow heron
tidal tartan
snow heron
# tidal tartan No, I don't use RenderLayers anywhere in my code.

Without any information about the models or your app I can't really help much. If you've already validated that the mesh and materials exist in your scene then try making the smallest bevy example and just spawning the scene instead to eliminate possible contamination from the test of your code

tidal tartan
snow heron
#

Probably not, if you've already validated that the mesh/materials you're expecting exist in bevy. Skein doesn't do anything that would cause a model to not render on it's own. It only inserts component data.

tidal tartan
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I'm not sure what is happening then, as it appears to exist logically.

2026-03-31-133736_2560x1440_scrot_000.png
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Decal_Ceiling_B_Light.001 btw

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Should look like this:

2026-03-31-133924_2560x1440_scrot.png
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Instead looks like this:

2026-03-31-134005_2560x1440_scrot.png
snow heron
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Is this the first time you've rendered a mesh as a child of a point light?

tidal tartan
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It's not a child of a point light. PointLight is added to the mesh data of the the model. The model is just called Decal_Ceiling_B_Light

snow heron
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Right, so you have a mesh and a point light on the same entity

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Have you done that anywhere else before and had it work

tidal tartan
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Yes. but this is probably the first time I've done it through Blender/Skein.

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Removing the point light does nothing

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Let's see what happens when I remove the material

snow heron
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Please be clear about what you mean when you say remove. Are you removing in egui? From the component list in blender?

tidal tartan
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In blender

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Ok, it shows up without the material

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Let's start removing stuff from the shader tab

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It's Emission

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This node going to the Principled BSDF node's Emission is what does it.

2026-03-31-135107_2560x1440_scrot.png
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Why's that, I wonder?

snow heron
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are the values > 1 in the emissive map?

tidal tartan
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You mean this?

2026-03-31-135450_2560x1440_scrot.png
snow heron
tidal tartan
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Setting Emission Strength to 1 doesn't do anything

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I suppose I could add a PointLightTexture through Bevy.

simple sigil
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I don't know what happened but skein suddendly doesn't load the color of spot or point lights anymore

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like every other property still loads but all colors are white for some reason, but not in blender

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I'll check the gltf to see if its export or import sided bug

snow heron
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blenvy?

simple sigil
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old habit ._.

snow heron
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Haha no worries, just checking to make sure

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I'm heading to bed at the moment but will check in on what you find tomorrow

simple sigil
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ok seems to be a blender-side bug

image.png
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made a minimal reprod without skein and the gltf is still [1, 1, 1] ._.

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blender bug report yay

opaque kite
#

Hi folks !
This has been driving me crazy for years in Bevy, and I am starting to think I have the wrong logic somewhere.
When spawning gltf files via the SceneRoot component , any components specified in the gltf file are always at best on the first child of the root entity (my_entity)

    let my_entity = commands.spawn((
        Name::new("Test"),
        SceneRoot(
            asset_server.load(GltfAssetLabel::Scene(0).from_asset("models/power_cable_coil.gltf")),
        ),
        AddToWorldRootContainer,
    )).id();

This causes , in my experience a lot of issues, because you cannot , in effect combine components coming from the gltf file with the ones you specify in the code at root level (which I find, is needed a lot).
So you end up having to go through various band aids:

  • use a custom command as outlined in the Skein issues: https://github.com/rust-adventure/skein/issues/50
  • use assetspawner with some convoluted boilerplate
  • either exclusive system(s) to copy components from the first child to the root entity (my_entity)(which I did back in Blenvy)
  • some convoluted logic in a lot of systems to go look for needed components "one child down"

Is it just me missing something about the logic of having the components data nested like this ?
Is something wrong with my mental model of how I structure entities & systems ?
Using gltfs to provide components / metadata is not "standard" as such, but it is used a lot
Please help me not go insane 😄
ps: I know about this potentially being solvable via bsn, but as an asset format it is still ways of, and even there I am not 100% sure this level of nesting will not be present

GitHub
Docs: SceneSpawner · Issue #50 · rust-adventure/skein

while we wait for bsn (maybe 0.18?) its useful to document the behavior of SceneRoot and SceneSpawner, specifically around the behavior of SceneRoot causing an additional parent node. Using the exa...

opaque kite
#

Semi related question : is there any way to execute code between the component insertion of skein and Bevy's SceneInstanceReady ?

snow heron
# opaque kite Hi folks ! This has been driving me crazy for years in Bevy, and I am starting ...

the first child of the root entity (my_entity)
Its worth differentiating between the scene root entity, which is defined in the gltf loader and is the root entity of a scene, and the arbitrary parent, which is identified as the entity SceneRoot is on (which is now thankfully renamed to WorldAssetRoot in 0.19).

I don't view SceneRoot as "what you should use". It is a restricted API for simple use cases, similar to the GltfAssetLabel (ex: you don't want to use GltfAssetLabel more than once to the same gltf file). and commands like spawn aren't inherently special, so if you want to manipulate a scene that you just spawned without using observers/sceneinstanceready a command is fine.

What kinds of things are you doing when you're spawning? for ex: what is AddToWorldRootContainer doing? That sounds suspiciously like ChildOf.

snow heron
opaque kite
# snow heron > the first child of the root entity (my_entity) Its worth differentiating betw...

Thanks a lot for the detailed explanation ! That is reassuring in a way. So the fact that I end up swapping out Sceneroot & co every time I go beyond some basic entity spawning with gltf assets is not abnormal.
Which makes me wonder if it would not make sense to add built in alternative "spawners" to Bevy at some point. (I am currently trying to use Bevy as purely a game dev and not a tooling dev, it makes me view things differently).

AddToWorldRootContainer in this case was purely for testing (most of the time that would be defined in code, not part of gltf assets), but the gist of it is:

  • it is for inventory/containers management, also uses Bevy relationships, ie there are Containers and InContainer components
  • yes sometimes there is overlap between that and ChildOf/ Children but not always: InContainer decouples the visual/hierarchical logic provided by ChildOf from the container/containee logic, it does not care about the actual entity transforms hierarchy & co
  • can be very useful for things like inventory that is NOT visible / tied to the world
  • this game world is also a container, so for example when the player picks up an item from the world, it is just a transfer between containers
opaque kite
snow heron
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So I'm not sure how much these alternative spawners would help, but they could be useful and are basically the custom command approach

snow heron
opaque kite
opaque kite
halcyon mirage
snow heron
halcyon mirage
#

ah 🤦‍♂️ my discord search didnt find it

snow heron
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Looks like the gltf exporter maintainer is going to look into it from that thread, but idk if they do back ports for built in add-ons and such

deft shale
#

Hi!
I wonder if there's a way to utilize components attached to Blender scenes so that when loading GLTF asset in Bevy it'd be possible to use those marker components to select from for spawning scenes without relying on actual Blender scene string names - that way naming part is controlled via skein registry so less of a chance to mess up

snow heron
deft shale
# snow heron how do you see this working?

In my pure imagination it could be like this:

  • defining an enum AppScenes as skein component
  • fetching remote type registry in blender
  • apply each enum entry to respective scene in blender in scene properties tab > skein bevy panel
  • upon loading gltf file at bevy runtime, generate a resource map [AppScenes -> Handle<Scene>]
  • manage scenes lifecycle by defined enum values overall
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thus I dont need to sync string values both in blender and in project sources, but keep just an enum in sync by api contract

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I came not to suggest a feature, I wish to learn about best practices for managing scenes in bevy properly 😅

snow heron
#

Basically the feature you're asking about is the equivalent of taking a json array and turning it into an Enum. It seems like a pretty per-project sort of feature, and could be accomplished by writing a build.rs if you wanted it

#

as far as how people manage scenes via glTF in general:

  • some people only ever include a single scene per gltf file. Its a simplified workflow that results in some additional constraints if you over-use it.
  • some people use multiple scenes from a single glTF file.

Either way, assets are a runtime sort of thing. You can load any given glTF file, and that asset contains the names of the various scenes, etc.

deft shale
polar trout
snow heron
snow heron
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I'm glad this made it into the 5.2 lts cycle

tidal tartan
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Before I start doing something, does Skein support linking from blender files?

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Like, can I add components to one file and link it in another?

snow heron
tidal tartan
#

Has anyone else experienced adding an animation breaks avian colliders?

snow heron
tidal tartan
#

No idea how, but after adding an armature and animation on a previously working mesh, the player will no longer collide with it. I can even see with an inspector that the object still has a collider and rigid body, but no collision happens.

snow heron
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Have you turned on the avian debug visuals yet?

tidal tartan
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let me see

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So apparently the collider isn't there, but still lists as existing in the inspector

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You can see a working door in the background

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no animation on that one

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In fact, this one is just a dupe of that one

snow heron
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The working door doesn't have any armature/animation/etc right?

tidal tartan
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nope

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Here's a shot of the door with debug and inspector view

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In fact, the hierarchy looks messed up

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For some reason Door_A_Door.004 is a child of Door_A_Door.006

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when there completely seperate objects in blender

snow heron
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004 is a mesh child of 006 object

tidal tartan
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No, they are, look at this:

snow heron
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Your screenshots are super low resolution when it comes to the text, I'm not sure why

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But that clearly shows Door.004 is the mesh child of Door.006

tidal tartan
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Ok then.

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Still not sure why the collider both exists/doesn't

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For some reason the collider is way up here:

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I'm guessing something to do with rigging and parenting

snow heron
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I wouldn't assume this is even a blender issue tbh. You can validate if *FromMesh works in one of the fox animation examples in the bevy repo

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does the collider that exists there look correct to you? Is it what you expect, just in a different location?

tidal tartan
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yup

snow heron
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are there unapplied transforms/etc on the blender objects? Is there anything special about that location (is it 0,0,0?)

tidal tartan
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Where can I check that?

snow heron
tidal tartan
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This is the unmodified object

snow heron
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I would also try using anything that isn't FromMesh. A 1x1x1 cuboid or something would be validating.

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tangentially: -32 meters seems like a lot

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is that a 64 meter wide door?

tidal tartan
snow heron
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oh cool. I can play around with that later maybe then

tidal tartan
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I'll mess around with some stuff

tidal tartan
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Seems like it was since kind of unapplied something

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After pressing enough buttons I got it working

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But now I'll probably have to redo my assets, since everything is using the unapplied versions

tidal tartan
#

Ok, now my issue seems to be the animation moves the mesh, but not the collider for some reason.

tidal tartan
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The more I try to understand Blender animations and Bevy, the less I do

snow heron
tidal tartan
#

What's confusing me though, is I was able to get this working before, and I can't for the life of me figure out how.

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I know I can just go the cop-out way and disable the collider.

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I did find out though that either bevy or skein, likes to attach the AnimationPlayer component to the top object in a hierarchy. If that object isn't an Armature, then whoops, no animation for you.

snow heron
tidal tartan
#

Calling it quits for today. But for tomorrow, is there any agreed upon way to get a collider to move with an animation?

dull lichen
#

You could probably tag them all with a marker component and then use iter_descendants along with a query filter to get them all

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Or attach an observer to them all for collision events if you don't need more detailed collision info

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if that doesn't work for whatever reason you could always just copy the transform yourself with a system but that's probably less efficient and more prone to error

tidal tartan
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With that said, now I'm wondering if there's a way to get bevy to insert the animation player on a specific object instead of the root parent. Because that would streamline and make things a lot easier.

loud bone
#

Is there a way to create mesh2ds in skein?

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Rather than mesh3ds?

snow heron
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But by default bevy treats all meshes as mesh3d

loud bone
loud bone
snow heron
loud bone
#

If I can figure out a good workflow for 2d stuff using skein I'm going to be so chuffed

tidal tartan
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When exporting to gltf, is it safe to toggle "Apply Modifies"? Because i've been manually applying them so far.

strange prism
snow heron
strange prism
snow heron
strange prism
snow heron
#

(I typed "gltf extension" there but I meant the upstream exporter itself)

strange prism
#

Well, that means I need a new workflow.

hollow obsidian
#

I'm getting the following error:

invalid glTF file: missing field `nodes` at line 1 column 117

But only when using the collection exporters described in here

Exporting: Multiple Collections

Collection Exporters can be used to export as many Blender Collections to separate .gltf files as you want

#

When I use File -> Export, I don't get this error. Is there a way to fix this?

snow heron
hollow obsidian
hollow obsidian
#

If I disable the anvil plugin it works now...

snow heron
#

yeah, I'm not sure what anvil does specifically, but some projects fork the gltf exporter and expect certain configurations. Skein doesn't fork the exporter, so unless the issue is a component data issue it is likely an issue with the other extension or things like geometry nodes being unresolved, etc

hollow obsidian
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Yeah, I think I'll give up on anvil for now since one here seems to be using it anyways which means finding help would be impossible lol

hollow obsidian
# snow heron yeah, I'm not sure what anvil does specifically, but some projects fork the gltf...

Btw, are there any updates on the collider workflow:
https://github.com/rust-adventure/skein/issues/16
I guess you should use ColliderConstructor::TrimeshFromMesh here? But doesn't that mean you will get lots of unused dummy meshes in the scene?

GitHub
Docs: Use Cases: Working with Colliders · Issue #16 · rust-advent...

While documenting Avian specifically isn't the goal, there are a number of questions people have around using and creating colliders that Avian would showcase well such as: How to add different...

snow heron
#

it depends overall on what you intend to accomplish workflow-wise. The FromMesh variants are easier to slap onto a mesh when prototyping, but you might want a selection of simpler cube-shapes "in production", especially if there are significant differences between the prod mesh and simpler shapes. You can also build custom meshes that just represent the colliders and used the convex hull from mesh variants, etc

hollow obsidian
# snow heron it depends overall on what you intend to accomplish workflow-wise. The FromMesh ...

Yeah for prototyping I'm already using TrimeshFromMesh. But I'm thinking of when you want to have a more optimized collider. The workflow I'm imagining is something like this:

  1. Have a complex mesh inside the Blender scene
  2. Insert a simpler mesh as a child of the complex mesh (so that you can visualize it in Blender)
  3. Insert TrimeshFromMesh inside that simpler mesh
  4. But now you have an unused dummy mesh in your scene
    Or maybe there's a simpler solution I'm missing here? 🤔
snow heron
# hollow obsidian Yeah for prototyping I'm already using `TrimeshFromMesh`. But I'm thinking of wh...

Yeah the "*FromMesh on a simpler collider" is fine. You might want to look into the convexhull variant, etc instead of trimesh which has infinitely thin walls. I see what you mean by "the dummy mesh", but getting rid of this would require pre-processing the mesh into an avian collider, and I don't think avian supports collider serialization despite having a "serialize" feature.

In theory there could be some workflow where the blender mesh marked as a collider was processed by avian into the representation it needed, then stored in a buffer in the gltf file and such. or something similar with .gltf file processing after export. but that requires avian to support that sort of thing.

If you don't want that "intermediary collider mesh", then it sort of depends on why you want to avoid it. What are you concerned about?

#

for example: using the avian primitive colliders and emptys would let you visualize cuboid colliders without an intermediary mesh.

hollow obsidian
snow heron
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there's docs on the site for that iirc

hollow obsidian
snow heron
hollow obsidian
snow heron
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also if you get into drivers they can do more complex things, like drive the collider sizes in a component via a different cube mesh, then not export that cube mesh

hollow obsidian
snow heron
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there's a couple of options like "export renderable" (or called something similar)

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so if you have two things, and you use one mesh to drive another's component value, the gltf exporter lets you "deselect" that mesh if it isn't visible to the renderer and such

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that's the little eyeballs in the outliner

hollow obsidian
snow heron
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ah unfortunate. well, one option is to not have the relevant mesh in the collection you're exporting

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idk what your export workflow is, but if you're using a bunch of collection exporters than not having the extra stuff in the exported collection is the straightforward way to do that

hollow obsidian
snow heron
hollow obsidian
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But out of curiosity, how would the shape of my hierarchies affect this workflow? My workflow is really rudimentary right now, just mostly following the docs with collection exporters

hollow obsidian
# hollow obsidian whyyy

I've found a little hack to work around this! What you do is open the File -> Export window, check the "Renderable Objects", then save it as a preset. Then load that preset in the collection exporter pane. The option won't be visible, but it would be silently activated underneath. Super hacky and I hope this will keep working lol

snow heron
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Oh my haha

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Architecturally that makes sense to me. I think the collection exporter is the same settings type in the code

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I wonder if it's just an oversight in the UI

strange prism
snow heron
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We can't end up hardcoding all possible custom serializations as fallbacks.

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And avian's approach here makes it so that the serialization is undiscoverable

strange prism
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I see. I didn't know there were usptream issues for this.

snow heron
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iirc your issue is the marker components change in serialization format right?

strange prism
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Yes, they appear in JSON as '{}' instead of 'null'

snow heron
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Basically we need to make a PR in bevy to have the option to completely avoid custom serde implementations when deserializing values

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And only use the bevy Reflect serializations

strange prism
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Are there multiple attempts to deserialize somewhere, and serde is preferred over reflection, or the like?

snow heron
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Basically that's what happens yeah

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I'm afk or I'd link to it specifically

strange prism
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OK, sorry for pinging you. I'm happy to wait.

snow heron
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The ping is fine, no need to apologize

strange prism
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Sure. I meant, when you were AFK 🙂

snow heron
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The only reason I haven't addressed the PR yet is because I was in flights this weekend and such so haven't had a chance to yet

strange prism
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OK, that's fair!

maiden bay
snow heron
hollow obsidian
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What you might want to do differently is separate the object representing the collider shape and the object where the collider component will be created on

hollow obsidian
maiden bay
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I'm creating a complex mesh in blender and want to add a simple collider when imported in bevy. I currently got to a point where I add a simple cuboid mesh as a child of the object in blender and add a marker component on the mesh using skein, then in bevy I use the mesh dimensions to create a collider and then remove the mesh from the entity. While it works it feels a bit hacky 😅 I saw talk about using empties for the colliders, would that be a cleaner approach?

maiden bay
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Was generally curious how other people import separate colliders from meshes using skein, should I be using drivers on one object or create child collider objects in blender

hollow obsidian
# maiden bay Was generally curious how other people import separate colliders from meshes usi...

If performance is not an issue (e.g. for prototypes) you can use ColliderConstructor::ConvexHullFromMesh or ColliderConstructorHierarchy on the mesh itself

ColliderConstructorHierarchy in avian3d::collision::collider - Rust

A component that will automatically generate Colliders on its descendants at runtime. The type of the generated collider can be specified using ColliderConstructor. This supports computing the shape dynamically from the mesh, in which case only the descendants with a Mesh will have colliders generated.

ColliderConstructor in avian3d::collision::collider - Rust

A component that will automatically generate a Collider at runtime using Collider::try_from_constructor. Enabling the collider-from-mesh feature activates support for computing the shape dynamically from the mesh attached to the same entity.

hollow obsidian
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Generally this is how I do it rn:

ActualMesh
└── Collider (e.g. ColliderConstructor::Cuboid)
    └── ColliderShape (never leaves Blender, it purely serves as a visual reference and its dimensions will drive the collider parameters above)
sick trout
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@hollow obsidian regarding anvil, ive been using it a bit but havent dug into it seriously yet, have you asked around in their discord server? it might be beneficial to alert them that people are using it in concert with bevy/skein

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it seems like their default assumption is that itll be used for godot/unity but i got the impression they wanted the extension to be generically useful

maiden bay
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appreciate the help!

primal pebble
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Did this ever come to fruition?

snow heron
primal pebble
primal pebble
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I'm not sure what to look for

primal pebble
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Hmm, is there a way to trigger an animation based on name instead of index?

snow heron
snow heron
primal pebble
snow heron
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obviously this is somewhat a personal opinion/workflow choice, and the support for "load asset then use" isn't particularly well supported either, but if you're using bevy_asset_loader or are willing to use the asset server to check for loading status then it is the better option imo

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you do get access to the names of everything if you load the root asset, named scenes, animations, etc, but the animation graph still accepts an index for the currently playing animation

hollow obsidian
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Is there a way to insert relationship components with skein?

snow heron
hollow obsidian
snow heron
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I published a 0.19-rc-compatible release

humble pewter
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@snow heron hey I am trying to get a simple scene in but it doesn't seem to work, I'm not getting any errors or anything

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I can share the blender file and code

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as well as screenshots

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the issue is that I have a cube, a camera and a pointlight but the scene is completely blank when I compile the game

snow heron
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You didn't check the box to export cameras and lights in the exporter

humble pewter
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working in order now

image.png
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thanks

hollow obsidian
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What would be the recommended workflow for working with terrains with skein? I imagine that exporting them as normal meshes would be pretty bad for performance, but I'm not sure. Maybe there is a way to export them as a height map?

snow heron
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You can export as mesh or bake a height map. What's recommended depends on what your use case is. Height maps are pretty common and you can bake and save them out.

I have a PR open to export arbitrary images into component values that I'm planning to merge after the rc process (it really needs blender 5.2).

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Also I wouldn't say anything was bad for performance unless I benchmarked it or had actually tried it

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If you use a height map, you still need a subdivided plane or whatnot to apply it to

hollow obsidian
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Maybe there's a benefit to heightmap-based colliders?

snow heron
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(departing on a flight so getting cut off 😆)

strange prism
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Have a good trip!

hollow obsidian
hollow obsidian
snow heron
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Yah, headed to rustweek/unconf

strange prism
snow heron
hollow obsidian
strange prism
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I have evidence for using a big mesh and TrimeshFromConfig to make the collider. The mesh is ~116k triangles, but scaled up to 256x256m, so almost always visible. I did indeed have to face performance issues not in rendering (tho my GPU is fast) but in the mesh collider. That's the major performance hit, via collision detection in Parry. (Also note I have a lot of objects colliding with the mesh.)

I had to split up the terrain into smaller chunks (96m/96m did it) to reduce the meshes enough to where the FPS improved.

I may have to consider the heightmap too... 😅

hollow obsidian
hollow obsidian
strange prism
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I.e. I had a heightmap image and went the hard way around! ha!

hollow obsidian
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I guess I'll shop around for a good terrain tool

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There has to be something that non-Unity/Godot/Unreal devs use right? 😆

strange prism
humble pewter
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@snow heron the website certificate is invalid

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it's currently impossible to access it

snow heron
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It just loaded for me