Materials and Textures for the 3D Artist

In this contribution, I want to share my experience on how to assemble a believable material texture and how an artist can achieve a good material definition. Your thought process during layer creation in Substance Painter matters a lot. Understanding the references and how a material is built in the real world can elevate the quality and realism of your work.

I’ve seen a lot of talented artists on the internet presenting beautiful portfolios with very clean meshes, zero shading problems, and good form & silhouettes. But because the viewer can’t visually feel the materials, they lack the material and textural quality of real world objects. Often this is caused by using the wrong values of color, roughness, metal, fine details or scaling.

Frequently, I’ll ask artists how they create textures through their creative workflows. It turns out that many of them created materials with just their mind, without visually inspecting a reference object. Very few artists usually know what bare metals or dark plastic or wood surfaces look like (including myself). Without a reference only really experienced artists could create realistic looks & feels, after they go through the creative process for many years. This is because the artist builds up an analytical process to be able to “read” and interpret the references with the right questions in mind. Without asking the right questions, you will probably fail to deliver outstanding realism or convincing textures and materials.

Always have questions in mind and ask the purpose of details such as deposits, surface height, scratches, and color variation. Here are some basic questions you should have in mind when creating any textures:

• What is the lighting condition on that material?
• What material am I really seeing?
• How is the material crafted in reality?
• What components is the material made of?
• What is the story behind the surface?
• Why does an object have scratches on some parts and why are some parts not affected?
• Who or what built the material? (Machines? Handcrafted? e.g.)
• What is the purpose of the object?

Only to name a few. There are endless questions that pop up during the process. For example, wood and metal are not like what you see at first glance. There are so many more details to see. The artistic eye should learn to go deeper into the layers to analyze the components of the texture. Here is a good example:

Comparing the two images we can see the artist’s mindset is different from how other people see this object. Creatives will see it and immediately ask questions or comments on how it could be reproduced in a digital space. You have to pay a lot of attention to the small details, technical requirements, physical questions and lighting conditions. That is why having reference images and reading/analyzing them is so important.

Physical-based rendering or PBR is a technique where the materials and surfaces react to light in a physically appropriate manner. It requires a different workflow and setup but it can make materials and textures look way more realistic. Especially within game engines such as Unity and Unreal engine.

There are 2 methods used in the games industry: PBR Spec/Gloss and PBR Metallic/Rough. Both have their pros and cons, however the last one is more developed and used in the real-time games industry.

Within PBR Metallic/Rough we used to work with 4-5 texture maps:

• Albedo – Color map
• Alpha – transparent or cutout map
• Metalness – masks map where bright is metallic and dark is non-metallic
• Roughness – surface reflection of the lighting
• Normal – stored light information from a high res mesh
• AO – shadow/self-shadow map
• Emissive – glow map

All these maps can be optimized by texture packing and be imported into many game engines. This is the latest standard in game development in regard to texture outputs.

The 10 Layers Theory

By optimizing the steps during layer creation we can easily end up with only a few layers representing the core features of a realistic-looking materials. I’ve seen many Painter files where you had to crawl through many unnamed layers, unorganized folder structures, and duplicated layers which basically have the same function or only little impact in the whole creation process, like single paint strokes or very few visible detail patterns. To create an interesting surface you need good contrast, an interesting variety of colors, and height/normal details which are clearly readable. The most valuable are the roughness values. The appearance of a surface is represented by the light reflection and thickness of an object. With the right rough or gloss value, you can establish the illusion of a real-life material represented in your textures.

In the blue plastic example, you can see that we only used 10 layers (including fancy sub surface scattering and an additional AO pass, so 8 layers) defining our surface look & feel. Please note that in this example we didn’t even spend a lot of effort in unique details as this material is fully procedural and could be applied to any other 3D object. Things like dirt, dust, fibers, leaks and other helpful layers to push this material even further are not even included.

Now you have the ingredients for creating all kinds of materials and even developing a more realistic approach within these layers.

In a production cycle, it is always useful to craft a material at first in a procedural way and focus on the unique layers like dirt, damages, and scratches last. It will help increase production speed as other artists can use your base material and continue with the fine details. Some materials will repeat often like: bare metal, plastic, rubber, and wood.

Collecting references is one of the most important actions when planning a 3D asset or starting something new. It will help you understand the proportions, width, height, and sometimes mass of an object. Especially for complex assets you want to gather as many images as possible to get to know the functions and shapes of a desired object. Understanding the crafting processes and treatments will help you understand the whole purpose. Modeling or texturing a weapon without understanding how it works and which kind of materials are being used will likely end up in a low-quality project. Taking time to collect and analyze the references and also understanding most of the parts will increase your project/assets quality.

Why you should Avoid 3D References

It is good to know that you should not really rely on other 3D artists’ works and use them as a reference as you cap yourself to the ability of another artist’s analysis process. If he failed reading a material, it is very likely you will fail that part too if you don’t use real-life references.

As you noticed in the image, we see 3D assets and real-life references. The key is to get as sharp (HQ) and big references from as many angles as you can find on a desired asset. The problem with 3D references is that the quality of many assets varies which means you probably have some quality differences on your asset which you will transfer over.

Let’s compare a low-quality 3D rendering vs. a high res image from a real AK-74.

Having the magazine in focus you can already notice the amount of detail in wear, tear, scratch markings, and dust in comparison to the 3D art which looks heavily procedural and unrealistic.

It is visible how much information an artist could gather out of a real image vs. a 3D reference created by an artist. No matter how good an artist is you should always prefer a real reference. It can be a good learning point to analyze 3D art from other talented people, but it can also hurt your quality level while reading materials and surfaces.

Research your Materials

To be able to create more realism, you need to collect all information about a specific metal, plastic, or any other element which will be included in your works. Images are good and reference too but without proper knowledge of the material it will be hard to recreate it in 3D. You want to know if rust is a metal or nonmetal, if dark metal exists (it does but maybe only 2% of the usage cases you have to deal with), or if scratches on plastics are dark or bright. All this information will help to increase the realism. Let’s have a look at some bad examples and at some good ones as well.

In the bad example you can clearly see that the artist did material creation out of their mind by recalling what they think they saw in real life. Because of that, they don’t understand how a material behaves in certain conditions. These 3D assets are not convincing enough to be called realistic.

Here, you can see that the artist used real-life references as they understand the material behavior when it comes to scratches and wear and dirt. They understood the layers of materials and successfully re-created them. Of course, everyone could use and learn from those 3D references but only to an extend the artist’s knowledge.

When you research a material it is good advice to read some articles, Wikipedia pages, or company information about processing. In the next example, we can see some collected references and created materials based on that information.

It is very visible that the artists took time to understand the process of melting/heating metal to an extent where they know which color will be seen depending on the temperature level. Also, they included already cooled-down fragment layers and heat emission. The edgewear shows clearly the thickness of an object and also already cooled colors can be seen. They identified the most prominent features of this reference and re-created them in a realistic way. There is always space to improve, the next step would be to create image compression (noise) and very fine particles.

To create realism the artist needs to know that things in the real world are not perfect. Many artists are perfectionists but nature isn’t. At the same time, it is as if the imperfection is amazingly beautiful. In nature, you rarely will see any plants or elements with even numbers instead many things will be arranged unevenly like 3,5,7. It is very important to remember to try to avoid perfection. Especially in digital art, it can be difficult as a PC runs with 0 and 1 commands which simply refer to “on” and “off”. Representing uneven surfaces, great contrasts, and imperfection is key to creating realism.

Noise Textures

A turbulent noise texture can help a lot in increasing realism. Using them will enrichen your details and you also can create some very interesting color variations. It can be seen in car shellac, dark captured images, and image compression. Using them in a very light manner can help achieve a real-life impression. Many materials have very few noise details but most likely they are there. On car paint surfaces we can see the noise very clearly as they have a different roughness value and they shine (gloss) more than the rest of the material. The closer you get the more visible it will be.

Noise is not just simple noise. There are hundreds of different noise maps and not every noise is suitable for different approaches – it is great to build up a noise library to be able to use a noise that can fit a specific material.

Also, it can be used in many ways, like height detail, simulating a bumpy surface, in roughness to create great contrast, color to simulate color variation, or everything combined together. There are many references where you can distinguish flat surfaces from noisy ones.

Basic Color

It is important to not use pure black or pure white to leave some range for highlights and darker tints. I tend to build up my materials a bit brighter in mid-range to have some space left. It is important to use all kinds of different color variations to create a believable texture as objects in the real world don’t exist in only one or two colors. Colors are affected in different ways such as erosion, contact with other objects, aging, leaking, weathering plus dust and dirt. The more color variation you place, the more realistic the textures will look.

Roughness

This is the most important texture. If your surface is too glossy or too rough the material definition is not convincing. Try to create a nice balance of reflective and non-reflective surfaces. The aim is to invent a nice readable roughness surface with great contrast and variation. Values of only black or white or a single grey tone won’t push any realistic feelings. A material lives from its roughness definition. Try to think where an object or material will most likely have gloss and where it shows areas of roughness.

Height Details

This adds the haptic feeling of a material. Be careful with scaling and the amount of details, as too many height lines or damages can produce very noisy results. As stated above noise is a great way to increase realism by representing small surface details. In Substance Painter, the height information will be stored and exported within the normal map.

Edge Highlights

To gain better readability it is recommended to highlight your asset edges by using curvature + levels or a generator/mask in Painter. Sometimes you want to break them or add variations to edges or customize them yourself with a paint layer. Also, I use a fill layer set to subtract on top of my mask stack to create interesting edges.

Fine Details

Usually, I do these things at the very end of my material definition as these layers can include hair & fur, particles, and all kinds of smaller deposits. Also, many artists use a Sharpen filter and AO pass on the very end to increase the contrast and sharpen texture details.

Polishing and Fancy Features

Most interesting for skin textures or offline rendering projects where you can use Subsurface Scattering or translucency materials to show how a light source is emitting through your surface. An additional feature is sub-surface scattering which allows seeing a fake light through the material effect. If you mask out thin areas and enable scattering you have the imaginary light that will emit through a thin surface.

Unreal Engine is a powerful game engine that can be used to create high-quality 3D graphics and interactive experiences. To create assets for use in Unreal Engine, there are a few key things that an artist should know.

Creating and Exporting 3D Models

The first step in creating assets for Unreal Engine is creating and exporting 3D models. Unreal Engine can import a variety of different file formats, including FBX and OBJ. When creating models, it is important to keep in mind the requirements of the engine, such as polygon count and texture resolution.

Textures

Once the models are created, the next step is to create textures for use on the models. Unreal Engine can use a variety of different texture formats, including PNG and TGA. It’s important to create high-resolution textures that will look good when rendered in-engine.

Materials

Unreal Engine uses a material system that allows for a wide range of visual effects. To create materials for use on assets, an artist should be familiar with the material editor and how to create and edit materials.

Lighting Example

Unreal Engine’s lighting system is highly customizable, allowing for a wide range of lighting effects. To create assets that will look good when lit in-engine, an artist should have a good understanding of the lighting system and how to use it effectively.

Before placing any lights, drop a Post Process Volume effect and change “Exposure” mode to manual and set 10,5 as the default intensity. Later, it can be adjusted towards lower or higher exposure depending on your scene mood.

Try to rotate your mesh by 30° angles or a slight tilting to show nice light reflections on the surface. This will help to support the visibility of your roughness map and also creates nice viewing angles.

I would recommend starting with basic lighting. Rectangular lights as filler and another rectangle light as a rim light. At the end, I placed some point lights to create interesting surface highlights.

Example Setup

1. Depending on your scene complexity it is a good idea to drop a Lightmass Importance Volume as it allows you to concentrate on an area (bounding box) that needs detailed lighting. Areas outside of the importance volume will only consist of lower quality.

2. Dropping a Post Process Volume will help you increase the overall look and feel of your scene by tweaking certain features light exposure, shadows, and scene tint. Here are some settings I used for the AK.

Once you are happy with your scene it is time to get some high-resolution images.

3. Change to a cinematic view/camera to be able to see crop frames. (Perspective→Cinematic Viewport). Also, you can drag & drop a cinematic cam or create one out of your current view (Settings→Create Camera Here→ CineCameraActor)

4. In Settings-> Screen Percentage” of 65-75 is the default – you can increase the amount depending on the level of sharpness you want to get. Higher values can cause color issues like 200% visible in the image.

5. Go once again to settings and High-Resolution Screenshot. Now increase the size multiplier from 1→2 and hit Capture. The image will be stored at “DriveLetter\YOURProjectPath\Saved\Screenshots”.

To be able to change the background color or editing effects later on, it can be useful to store an alpha channel by turning on Specular Buffer Visualization. You can add a pure white color by using a 1 vector node in your master material as the image shows. Capture the specular buffer viewport as well without moving the camera or perspective as these two captures need to be overlaid later in Photoshop.

Post-processing, also known as post-production, is the process of editing and enhancing digital images after they have been captured or created. This can include color correction, compositing, and the addition of special effects. In the world of 3D art, post-processing can be used to give the final touches to your renders and make them look even more realistic or stylized.

Post-processing is an important step in the 3D art workflow, it allows you to bring out the full potential of your renders and make them look their best. The most popular Software to use is Photoshop. Here’s a quick guide on how a 3d artist can use Photoshop for post-processing:

1. It is a good idea to have a library of post effects like dirt maps, camera lens deposits, and bokeh images to slightly overlay them on top of your rendered image.

2. Import both of your screen captures; image and buffer visualization in Photoshop and use the Magic Wand tool to create a selection and mask your image so you can replace the background with any image you want. I prefer a blurred image and I never use a very dark one to avoid bad readability of silhouettes and shapes. In Marmoset, you can set a custom HDRI from Poly Haven and render a blank scene image with just HDRI.

3. Now I start adding some Color Correction layers and bokeh effect images. Use a very small amount of 8-12% opacity in Color Dodge blending.

4. Save and export your image as png now and open it once again. Create a copy and apply a Filter->Camera Raw Filter. Here you have a lot of settings you can tweak after rendering to change the mood again or brighten/darken your image or get more contrast or a sharper image.

5. Select the Filter
6. Press the “Y” symbol to see a live comparison of your image
7. Adjust colors, brightness, and tint to change the mood of your image
8. In the top bar you can increase your sharpness once more. Especially if you want to publish your image on Artstation or any other website you will face image compression.
9. Apply everything by hitting OK and add a description, web URL or your name to the final image.