GLB always black

scaled_origin.glb (1.8 MB)

Hi guys. I am new to Three.js and facing a very strange problem. After loaded using GLTFLoader, the model always show black even I put some meterail on geometry and lights in the scene.
Any comments on that?
Thx so much.

It looks fine when importing it into the following three.js based gltf-viewer.

Without seeing your code, it will be hard to tell what’s going wrong.

Note that if the material is metallic, you must add an environment map. Otherwise you’ll need to show what your code is doing – there are many examples of GLTFLoader use in that do not have this issue, so it is something in the details of your project.

Thx a lot. @donmccurdy @Mugen87
The problem is about normals.
fix everything.

This method has no effect when using BufferGeometry.