load_untyped has issues loading scenes from gltf files

[NiklasEi]

Bevy version

0.12.0

What you did

Load a scene using AssetServer#load_untyped

The following code crashes with a type Id miss match:

use std::any::TypeId;
use bevy::asset::LoadedUntypedAsset;
use bevy::gltf::Gltf;
use bevy::prelude::*;

fn main() {
    App::new()
        .add_plugins(DefaultPlugins)
        .add_systems(Startup, load)
        .run();
}

#[derive(Resource)]
struct MyHandle(Handle<LoadedUntypedAsset>);

fn load(mut commands: Commands, asset_server: Res<AssetServer>) {
    println!("untyped {:?} scene {:?} gltf {:?}", TypeId::of::<LoadedUntypedAsset>(), TypeId::of::<Scene>(), TypeId::of::<Gltf>());
    commands.insert_resource(MyHandle(asset_server.load_untyped("models/AlienCake/alien.glb#Scene0")))
}

The app does not crash when directly loading the asset as a Handle<Scene> (as expected).

What went wrong

This crashes because at some point it expects a handle Id to have a different type id than it actually has (seems to be Gltf instead of the expected Scene).

Log and partial stack trace from running the code above as an example:

2023-11-08T16:58:33.116118Z  INFO bevy_winit::system: Creating new window "App" (0v0)
2023-11-08T16:58:33.116695Z  INFO winit::platform_impl::platform::x11::window: Guessed window scale factor: 1    
2023-11-08T16:58:33.320571Z  INFO bevy_render::renderer: AdapterInfo { name: "NVIDIA RTX 2000 Ada Generation Laptop GPU", vendor: 4318, device: 10424, device_type: DiscreteGpu, driver: "NVIDIA", driver_info: "535.129.03", backend: Vulkan }
untyped TypeId { t: 52159753730012975514151558583186680988 } scene TypeId { t: 312902742491752564684897985457935864593 } gltf TypeId { t: 129217342951176499515112392938364371523 }
2023-11-08T16:58:33.575293Z  INFO bevy_diagnostic::system_information_diagnostics_plugin::internal: SystemInfo { os: "Linux 22.04 Ubuntu", kernel: "6.2.0-36-generic", cpu: "13th Gen Intel(R) Core(TM) i9-13950HX", core_count: "24", memory: "62.5 GiB" }
thread 'main' panicked at /home/niklas/code/bevy/crates/bevy_asset/src/id.rs:266:9:
assertion `left == right` failed: The target AssetId<bevy_scene::scene::Scene>'s TypeId does not match the TypeId of this UntypedAssetId
  left: TypeId { t: 129217342951176499515112392938364371523 }
 right: TypeId { t: 312902742491752564684897985457935864593 }
stack backtrace:
  <-- snip assert failure/panicing and unwinding --> 
  18:     0x55c495afe2c9 - bevy_asset::id::UntypedAssetId::typed::h23a6c230e3c26f34
                               at /home/niklas/code/bevy/crates/bevy_asset/src/id.rs:266:9
  19:     0x55c494f3b3b9 - <A as bevy_asset::loader::AssetContainer>::insert::h699f3d5e5a4a5014
                               at /home/niklas/code/bevy/crates/bevy_asset/src/loader.rs:238:50
  20:     0x55c497093e92 - bevy_asset::server::info::AssetInfos::process_asset_load::h1bfe159cce1417a5
                               at /home/niklas/code/bevy/crates/bevy_asset/src/server/info.rs:309:9
  21:     0x55c49711bb8d - bevy_asset::server::handle_internal_asset_events::{{closure}}::h50063b5502c785a4
                               at /home/niklas/code/bevy/crates/bevy_asset/src/server/mod.rs:856:21
  22:     0x55c497027e88 - bevy_ecs::world::World::resource_scope::h49aa2bd32f19e8ad
                               at /home/niklas/code/bevy/crates/bevy_ecs/src/world/mod.rs:1571:22
  23:     0x55c49702d05b - bevy_asset::server::handle_internal_asset_events::h323538561b60f547
                               at /home/niklas/code/bevy/crates/bevy_asset/src/server/mod.rs:851:5
  <-- snip system calling --> 
Encountered a panic in exclusive system `bevy_asset::server::handle_internal_asset_events`!
Encountered a panic in system `bevy_app::main_schedule::Main::run_main`!

Additional information

This currently breaks loading scenes in bevy_asset_loader

[NiklasEi]

I think it's failing because get_or_create_path_handle_untyped uses the type id of the loader (here Gltf), although the type id for the requested handle might be different if loaded as a "side product" by said loader.

[Selene-Amanita]

It seems to happen here:

bevy/crates/bevy_asset/src/server/mod.rs

Line 446 in 0cc1179

id: labeled_asset.handle.id(),

For some reason just before the bug happens, labeled_asset.asset.asset_type_id() and labeled_asset.handle.id().type_id are different

Edit: diving deeper:

untyped TypeId { t: 237053916966532227674992742134880052298 } scene TypeId { t: 109858301795979688433023594662162045982 } gltf TypeId { t: 125106640790734373050133807998316083405 }
<...>
[/home/nocta/Travail/Perso/Contributions/bevy/crates/bevy_asset/src/loader.rs:376] handle.clone() = StrongHandle<Scene>{ id: Index(AssetIndex { generation: 0, index: 0 }), path: Some(cup.glb#Scene0) }
[/home/nocta/Travail/Perso/Contributions/bevy/crates/bevy_asset/src/loader.rs:377] handle.clone().untyped() = StrongHandle{ type_id: TypeId { t: 125106640790734373050133807998316083405 }, id: Index(AssetIndex { generation: 0, index: 0 }), path: Some(cup.glb#Scene0) }

Edit 2: here:

bevy/crates/bevy_asset/src/server/mod.rs

Line 391 in 0cc1179

loader.asset_type_id(),

path is cup.glb#Scene0
loader.asset_type_id() is 125106640790734373050133807998316083405
loader.asset_type_name() is bevy_gltf::Gltf

[Rust-Ninja-Sabi]

have same error with gltf