Mesh, shader & light

Questions
1

Hello !

I don’t really understand for the moment how works shader, but if somebody know how to simulate light (Undirectional light, spot, …) in 3D scene with mesh and shader, that could be great !

Thanks

2

I did a lighting shader class.

http://twolivesleft.com/Codea/Talk/discussion/2379/ads-lighting-class#Item_1

3

Thanks a lot !