Hello resident Unity graphics experts,
I have a newbie question regarding which is better practice - having 2 materials on 1 mesh, or having 2 materials, one on each of 2 duplicate meshes. Please refer to the image below.
I’m making an animation where the yellow object slides down a tube. I have 2 shaders (one opaque and one transparent) that clips off the Geometry around the object. The effect I’m going for is that the tube turns transparent where the object is so you can see it move down. I current have 2 identical meshes, one with a material with one of the shaders. The opaque material is set to clip inside a sphere, while the transparent one is set to clip outside the sphere. The radius of the clipping effect are the same, so it looks like the tube is turning transparent. Everything works as expected.
However, I just recently found out I can have 2 materials on the same mesh that would do this very thing, but I get a warning when I do this about a performance hit if 2 materials are on a single mesh. My question is, which is actually the better practice? Having 2 meshes with 2 material each superimposed over each other, or having 1 mesh with 2 materials? I’m very new to Shader coding, so I don’t have any reference to what is proper practice or convention. Is it faster to render 2 meshes with 2 materials or 1 mesh with 2 material?
Note that this thing has to run on a mobile device, probably a Android phone within the last 2-3 years. Also I’m on Unity 2018 because the app I’m working on was start there and I’m not allowed to move to a new version. Probably doesn’t matter but thought I’d mentioned that just in case it makes a difference.
Thank you in advance.