3D 3d Vertex Lighting

[RujiK]

I'm trying to implement a bare-bones diffuse style lighting for a 3d model. (Lighting that is calculated by the angle of the triangle face vs the angle of the light ray)

I have found many tutorials for this, but so far all of them involve baking your normals into your vertex buffer. Unfortunately, my 3d model is going to be heavily animated by the vertex shader, so baking the normals won't really work (I think?) since the triangles will be moving and turning.

So, I guess my specific question is: Can you calculate the normal, and thus the lighting, of a vertex inside the vertex shader?

Thank you for your time.

 

[Binsk]

Modify your normal value with the same rotations as your vertex before calculating the light in the shader. Normals are pretty essential for lighting.

 

[Fanatrick]

You always need to "bake" normals into a vertex buffer, how else would you represent facing direction per vertex? You're already translating/rotating their position components, you can do the same with the normal.

EDIT: ^ beat me to it

 

[Yal]

Unfortunately, my 3d model is going to be heavily animated by the vertex shader, so baking the normals won't really work (I think?) since the triangles will be moving and turning.

Transform the normals with the same operations as you do the vertices, then pass them on as a varying to the fragment shader? Normals are pretty much essential to lighting, there's no getting away from them.