Load GLTF/GLB misses an object clearly in Blender

[fgadaleta]

This is how I load the gltf/glb

struct SceneHandle {
    handle: Handle<Gltf>,
    animations: Vec<Handle<AnimationClip>>,
    instance_id: Option<InstanceId>,
    is_loaded: bool,
    has_camera: bool,
    has_light: bool,
}


fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
    // Load scene
    let scene_path = "../assets/hangar.gltf".to_string();
    info!("Loading scene {}", scene_path);
    let gltf_scene = asset_server.load(&scene_path);

    commands
    .insert_resource(SceneHandle {
        handle: gltf_scene,
        animations: Vec::new(),
        instance_id: None,
        is_loaded: false,
        has_camera: false,
        has_light: false,
    });
}

Blender version

How Bevy renders the scene (ladder not present)

The ladder is actually outside the hangar

[mockersf]

could you share your model?

[fgadaleta]

the gltf is something like 0.5GB
sure i can share. How?

[alice-i-cecile]

Perhaps post a link to Google Drive / Dropbox, or some other file hosting service?

[fgadaleta]

Ok I have simplified the .blend file and exported to a smaller gltf that still reproduce the loading error.
Please find the gltf here
https://drive.google.com/file/d/1ePfyheHnzydXRJcSLFmJF9MN1pKea6VJ/view?usp=sharing

[mockersf]

Here is a very simplified version:
very_simplified_hangar.glb.zip

In Blender (and other gltf viewer), the ladder is under the drone. In Bevy, the ladder is on the other side of the wall

[fgadaleta]

exactly

[mockersf]

This would probably be fixed by #4379, or one of the other issues about transform order.

I tried changing

bevy/crates/bevy_transform/src/components/global_transform.rs

Lines 209 to 218 in 4bcb310

	pub fn mul_transform(&self, transform: Transform) -> Self {
	let translation = self.mul_vec3(transform.translation);
	let rotation = self.rotation * transform.rotation;
	let scale = self.scale * transform.scale;
	Self {
	translation,
	rotation,
	scale,
	}
	}

to

    pub fn mul_transform(&self, transform: Transform) -> Self {
        let (scale, rotation, translation) = (Affine3A::from_scale_rotation_translation(
            self.scale,
            self.rotation,
            self.translation,
        ) * Affine3A::from_scale_rotation_translation(
            transform.scale,
            transform.rotation,
            transform.translation,
        ))
        .to_scale_rotation_translation();
        Self {
            translation,
            rotation,
            scale,
        }
    }

and it fixes the issue

[oddfacade]

yeah, it looks like the current implementation is effectively doing

when what you actually want is

(non-uniform) scaling and rotation don't commute.

[superdump]

I was just pointed to this issue. I'm glad it would be fixed by #4379 . Also, the images at the beginning feel like a meme, and I love it. :) Maybe bevy merch with "The ladder is outside the hangar" and zero context. :D

[mockersf]

this is fixed now that #4379 has been merged

(it's now not displaying anything due to #5334 which will be fixed soon)

[mockersf]

completely fixed with #5335!