Not quite sure how to set up PBR textures

RaptorCWS

So this is the first time I have attempted a PBR texture workflow. Im doing metallic/roughness. I understand the more white in the metallic the more metal looking the object is and the more black in the roughness the more smoothed a surface, like a mirror, is. what I do not know is how to quickly set up those setting for materials like leather, skin, or cloth. Is there a chart out there or is it more of playing it by eye with a reference? I have read marmosets posts on the subject I just want to make sure I am going to set up my base materials as close to correct as possible. I'm using Substance designer so I can just use a smart material from ddo.

Jerc

Creating the Metallic channel is easy: any non metallic surface (leather, skin, plastic, wood,etc.) will have a black metallic map and any metal will have a white metallic map.
The only time when you want to use values in-between is if for creating dirty metal for example, or metallic car paint, but most of the time you want to keep your base material clean and then apply tear and wear as additional layers.

ZacD

There's a bunch of charts online if you google around a bit. The main thing you have to figure out is it a metal or not, then you figure out the specular or albedo value, which you'll need reference charts for. Roughness can be done pretty much by eye, or asking yourself how big of a highlight would this material have from a light.

Quack!

First! If you are making a stylized material, follow no conventions, just make the material how you want it. For realism, here is how I start.

Metallic - Is the object metal? No, 0(black), Yes, 255(White). Simple. There are some intermediate values, but your metallic map, unless stylized, will consist of little range per material. Most values will be in the top or bottom of the value range of black to white.

Roughness - This is a bit more nebulous. Start with the same questions. Is this surface VERY rough to the touch? Yes it's very rough, start high in the 200-255 range. No, its smooth, 50-100 range. There are some values out there for these, but it is up to the artist/art department, to set the values themselves. Try to focus on the reflectivity of real world material in different lighting conditions. When in doubt, get close and guess.

With Substance Designer, I found that using SD properly is more important to getting your materials to read rather then having world accurate values. If you are using SD like photoshop then you are going to run into material troubles. If you play to SD's strengths then you are going to get the most out of your materials. Playing to SD's strengths means that you are creating a bunch of very basic base materials, with the least amount of detail in them to define a clean surface. Then you are mixing those materials together via masks and adding the layer of dirt/grime/transition further down the graph. This will help keep your materials separate and well defined.

Rather than trying to rely on real world values and charts, I would focus on being consistent within any style you have chosen. This will vary wildly per game, per studio, per person.

RaptorCWS

Thanks everyone. Ill get back to textureing in the AM

louiecai

Bump, If a model has no metal parts in it, do you not include a metal map or put one thats full black in it anyway? Same for the others, confused on what specular and glossy is, whats the difference? I'm doing a cloth lined ottoman chest and I need photo realism.In substance painter I got the albedo, normal, and AO but its shiny and still kinda off Do I use roughness? Or a all black metallic/specular/glossiness to get rid of the shine? stuff like that.

poopipe

I output all maps for every material and then decide whether to use them in Shaders or not later. Consistency is a huge help once you have a load of materials built. 

Also, Use the pbr Base material  node as the foundation of your materials so you can ensure you're getting good values. 

EarthQuake

You basically always want a gloss or roughness map, unless you have a perfectly clean and even surface, which is exceptionally rare. More on the topic:

https://www.marmoset.co/posts/physically-based-rendering-and-you-can-too/
https://www.marmoset.co/posts/basic-theory-of-physically-based-rendering/
https://www.marmoset.co/posts/pbr-texture-conversion/