Appropriate settings for importing unlit Maya models into Unity3d? -

if not using lighting in game in unity3d , models have lighting baked in textures, of 2 methods of importing models better.

(import settings in unity inspector).

1. importing models no normals
2. importing normals.
3. importing calculate normals , setting smoothing angle 180.

the shader i'm using not use normals don't have problem no normal importing. 1st method reduces vertex count most. i'm wondering if no normals reduces of optimisations such face culling etc.

in short best settings importing models if no lighting used.

importing without normals work specific case you're mentioning: prelit models don't shading @ all. however, if want angle-based effects @ (fresnel highlights or toon shading, example) you'll need normal information.

you better optimization on model if don't have normal information, since none of verts have split handle edge creases.

if have manually edited normals in maya (particularly flipped normals or used 'conform') may find importing mesh without normals causes triangle revert natural orientation - may affect culling.

so: using no normals ok limited case of lightmapped unshaded geo, not else.