"Material modifier" in a 3d model

How do I...?
1

I’m wondering how I can change the Material Modifier parameter of a 3D model during the game.

Is it possible to change one of these parameters to choose from:
“No lighting effect”
“Emit all ambient light”
“Save model material”.

And another question, which is less loaded on the system:
“Emit all ambient light”
“Save model material”.

I have experienced a drop in fps when there are more than 20 models on the screen. I would like to optimise this somehow.