PIPELINE TECHNIQUES: Photorealistic tyres in Substance Painter
Pro texturing tips from Amaru Zeas
When it comes to the creation of textures for cg assets there are different ways to achieve the results. After three years of using substance Painter i believe that Allegorithmic is changing the cg industry in videogames, movies and commercials by providing amazing tools to create PBR nondestructive textures very quickly. Allegorithmic’s substance Painter, substance Designer and substance B2M are powerful tools. each one gives you different approaches on creating textures but they can also connect to each other. substance Painter is a great tool that allows you to import your 3D object and paint textures in real-time.
As mentioned, Painter allows you to work on a nondestructive workflow, which will drastically help you when you want to make fast changes.
i still remember my first project using substance Painter really well. it was fan art of the most recent Mad Max movie. Before using substance Painter, i pretty much created all my textures using photographs and painted them in Photoshop. Well, that was a laborious, painful process. Just before working on my Mad Max project, i did some research on new tools to help me create textures more quickly. i found a few options, but when i saw some Youtube videos on substance Painter, i couldn’t believe how easy it was to learn the basics! since then i’ve never stopped using it. in this tutorial i would like to share most of my tips and tricks to create photorealistic textures for race car tyres to use them in either a cg renderer like Arnold or in a real-time renderer like unreal engine.
01 New file and baking textures There are two different types of workflow; Metallic Roughness and specular Glossiness. We will be using the Metal Roughness workflow. choose your project texture resolution (you can change it at any time), select your object and workflow, and create the new project.
it is very important to bake our textures. in the Texture set settings, we want to click on Bake Mesh Maps. here you can choose any maps you might use. Remember you can always go back and re-bake or bake missing maps. i tend to bake in 4K resolution and with at least 2x2 Antialiasing for smoother curvature maps.
02 Work non-destructively i try to work procedurally as much as i can so i can adjust the look of my materials quickly without destroying my work.
substance Painter has Regular layers and Fill layers. i use Fill layers as an actual material. i love working with fill layers because they can be modified at any time.
To keep things nondestructive, i usually use masks and leave the layers alone. The usage of Groups is key to making master materials and keeping thing organised. it is important to name and be specific as much as possible.
You can also use these materials as a base and then start working on top of them to make the materials unique. in this case i have used the material called Rubber Vulcanized Raw
03 Base rubber texture Allegorithmic offers substance source, which is a PBR material library with tons of resources. You can access it by either clicking on the icon on the right tab or just simply by going to the web: source.allegorithmic.com/assets. however, i try to create most of my materials from scratch as much as i can, it helps to achieve more unique features and gives more control. You can also use these materials as a base and then start working on top of them to make the materials unique. in this case i have used the material called Rubber Vulcanized Raw as my base rubber. This material gives you a perfect start.
04 Real-world details The more references you gather, the more convincing the textures you create will look. i always try to find references in different types of lighting since i like to see how materials interact in the real world. it is very important to pay attention to texture scale. Many artists make mistakes with just adding details with the wrong scale, this will make your texture not look believable. sometimes small details are better even if you think they won’t be seen by the viewer.
05 Add age to the rubber As i mentioned before i like to leave my base material as simple as possible so then i can start adding more details.
if you use the Metallic Roughness workflow you know that the roughness textures will determinate the look and feel of your material. i like to add two or three layers to add extra roughness. For this i just create the layer and leave only the roughness channel, then i create a mask and i can apply a Fill. in the Fill slot i usually use the procedural textures in the substance Painter library.
i have seen artists add many details to their textures but sometimes they just look lifeless. For a tyre i add some directional dirt on the tread just to make it look that there has been motion
06 Add motion to the textures it is good practice to add motion to the textures. in real life nothing is static. i have seen artists add many details to their textures but sometimes they just don’t make sense or look lifeless. For a race tyre i like to add some directional dirt on the tread just to make it look that there has been motion.
For this i create a new layer and this time i use all channels. Also, i like to add a texture into the colour channel and lower the intensity as this helps to bring a bit of dirt variation. Then i create a mask where i add a Fill. here i can add the directional look i want.
07 Add dust and extra dirt sometimes we forget to use the map textures we baked at the beginning. Often i use the curvature map to add details on the edges and the occlusion map to add some dust and dirt. To do this just create a new layer, keep colour, Roughness and Metallic maps and make a very opaque material. There are two options. You can either just add a Fill and then add your AO baked map or just make it more complex.
08 Instance Layers The usage of instance layers is great when you have multiple objects in different layer sets and you want to share the same material, because when you make a change it will affect all the layers that have the instance. i used instancing with the base rubber material so i can have the same clean look for all three parts of the tyre and then just add the wear separately. To do so just right-click on the layer or folder then go to the instance layer and then select the texture sets you want to apply it to.
09 Paint the details i like to paint details after i am done with the procedural. sometimes small details can add more realism. in this case i decided to add some chalk marks. For this i start with creating a Fill layer and lowering the Roughness. Then i create a mask on that layer where i add a Paint filter so i don’t affect the layer, this way i can change the colour at any time.
There are many brushes in substance Painter and i ended up using the chalk brush. To create the normal map for the big logo on the tyres i do the same approach, create a fill layer, only this time i leave only the height channel with some value, then create a mask and finally add a Fill on the mask to add my Logo Alpha texture.
Amaru Zeas amaruzeas3d.com Bio Originally from Cuenca, Ecuador, Amaru is a senior 3D artist based in Seattle, Washington. Currently he works at Amazon Game Studios as a senior 3D artist.