I’m dissatisfied with how the eyes look on my model with a simple texture. So I was wondering if there is a limit to how many textures/materials you can assign to character’s model. I wanted to add one for the pupil, one for the iris and one for the whites, on top of the 6 mats I already have for the various parts for a total of 9 mats. I know in second life you can only have 8 total “faces” but I’ve made some stunning models with those 8 faces, which might show up in my game at one point but anyway. How many mats can I have or is the sky the limit?
The eye should really be one material. Each material is another draw call. There’s no benefit from breaking the eye down into multiple materials, you should be using textures and the material editor to tweak that level of detail.
ok, just checking. I actually decided to just roll with what I had, and to remove all the extra ones for simplicity in the final export. When I am working on painting/creating a model I often use the mats to divide it up for easy selection then if I don’t need it I’ll just drop them all and use one… While we are on the topic of images, how large is too large for the main character. I currently have 1024, but I’m thinking about boosting it up to 2048 for the main characters so I can add more detail, especially in the normal map
Up to 2 or 3 2048 textures for a main character in a modern AAA game is common.
You probably want to author in 4096 for each major body part (head, upper, lower, for example,) and then perhaps downsize to 2048 for shipping if size or memory usage is a problem (which it will often be, depending on target.)
Regarding having tons of separate materials, if all you want to do is vary the degree of Fresnel or reflectivity or whatever, it’s usually much better to have texture maps for each of those parameters, and paint different parts of the mesh with different values of the multiple textures, than to have multiple shaders. Especially when the amount of pixels covered on screen are not that large (eyes are a fantastic example) this is super important, because doing 8 draw calls for a single eye is a losing proposition compared to doing one draw call with 12 separate texture maps used in that same call.
Reading your responses, I’m not sure if you get the standard texturing process or you just don’t have the tools to properly texture. How are you going about the materials for your character?
The character’s head will be one texture. The eyes another. The body is typically at least one or two textures. If the body is going to have parts that swap out or clothing options, any part that will stay the same will normally be on one texture.
well, I prefer to have 3 textures on the body itself, like second life does it, but the open source models that I am using only has 1 texture. And since I want the texture to be compatible with future versions of Manuel Bastinoni, I want to make sure I keep to the single overall texture. What I meant as mats, is to have the pupil, iris, and white on different mats so I can just color them in UE4. I plan on creating a cell type shader so I need simple textures to begin with. No bump, no displacement and probably no normals. If there is any of the prior then they will be light to prevent distortion. I haven’t gotten far enough to build an advanced shader yet but I do know what I want and I believe I can get there without buying it from the market place when I get that far. Thanks to the wonderful example provided by the stylized rendering sample. Currently I am in the main character creation phase. I’m tired of looking at the mannequin and want to see my own character.
Speaking of clothes, yes they will be separate, and equip-able. For ecample, Alex is a cop and you will be wearing the uniform party of the time but you can collect her outfits to wear in her off hours or undercover. Some missions will require a certain outfit you must find before you can complete it. So I’ll also need to know how to add a censor mat when she has nothing, or partial equipped. I don’t want her bits to show when someone decides to just wear a skirt, ya know. 
Or I’ll just default her to wearing undies.