object3D become black when change material

I’m having problems with simples GLB files where I try to change their material (lambert), and they immediately turn black.

I have created a jsfiddle here

And I share a couple of models where this happens.

If you can help me or give me a clue, it would be a great help. Thank you.

Your geometry does not have any normals.

You can use Geometry.computerVertexNormals as a work-around, but it’s best if you fix your geometry so that it has proper normals exported (you can test whether or not your object will work nicely with lights by applying MeshNormalMaterial - if it’s pink/green/blue it’s ok, if it’s black the normals are missing.)

1 Like

Thank you. @mjurczyk you are right!