Double-Sided Shader or Model Backfaces

Noth

I'll give some context -- Working on a mobile game, modelling some teeth for a dinosaur. We'll see the through the mouth and see the back-sides of the teeth. I'm thinking I'll use a double-sided shader, but I could also model the back-sides more simply than the front.

Could anyone give me some direction on the best course of action, and maybe your considerations for the decision? Thanks!

Obscura

I would say these days it wouldn't matter because a 2 sided shader is cheap and an extra 100 polygons won't change anything either. So then I'd go with the shader.

Noth

Excellent, thanks.

Noors

Im not a render pipeline expert but a double sided material is certainly more costly than duplicating a bunch of tris. It will be applied to all model, causing more overdraw, shader will have more instructions...I dont see the point to use it in your case especially on mobile.

gvii

I think its better to have a double sided shader for specific things and everything else culled, but with that said, I tend to do a duplicate and inflate/z translate to create backfaces since I can do darker shading for hand painted stuff, which takes advantage of the situation to make it look better. With the case of teeth though, making it paper thin will end up looking strange, so its better to do modelling with thickness. You can do mesh for most teeth and insert fangs and such over the regular mesh to break up the shape.

poopipe

It all depends on the renderer and the wider context it's used in. 

Adding draw calls is probably more costly than a couple of hundred tris so adding material and breaking any batching that might be going on probably isn't the best idea.  If you have a render programmer, ask them.   if not I'd suggest you just go with geometry and LOD it sensibly.