So I have been really excited about using blended materials to make a truly next gen looking level. But then I cam across this article
and at the end a caveat says
"Although Layered Materials are useful for handling multi-Material setups, care must be taken when employing them. They can be heavy in terms of performance, particularly if the Materials used in the layers are complex in themselves.
Keep in mind that all of your layers are rendering simultaneously, and then blended. For instance, if you had 4 layers in a Material, then for each pixel of your object, the system must test to see which of the four is blended, and rejecting any not in use. This added calculation makes the Layered Material more performance intensive.
Your first impulse may be to use Layered Materials any time you wish to have multiple surface types on an object. For instance, if you have a model of a car, you may want to have one Material Layer for paint, another for steel, for rubber, for glass, etc. However, many of those Materials could be separated at the geometry level. This creates more Material Elements on your objects, which increases draw calls, but is generally much more efficient. In short, if you can apply multiple Materials instead of using a Layered Material, then do so. If you must have per-pixel control over where Materials are placed, then use a Layered Material.
Although condensing multiple individual Materials down to one will reduce draw calls, the resulting Layered Material is generally going to be too heavy for this to be considered a mobile feature."
I wanted to make a level with every material being being a layered material, all of them sharing the same small library of material functions. Now I’m scared to go ahead because the caveat explains its inefficiency. I would think that instead of having many complex materials I could just have less complex materials that all talk to a small library of material functions. In the long run it would be more efficient because my sharing in the same material functions less nodes are needed in a material. But now I guess I’ll have to do things the old fashion way. Really a shame because I thought that these layered materials are what is going to make next gen games look so next gen.