Tips on Using PBR a.k.a. Physically Based Rendering in Your 3D Model Design
PBR is quickly becoming a standard in 3D design. If you didn’t already know, PBR stands for physically based rendering. We are not talking beer, that’s a different PBR. PBR and photorealism go hand in hand when it comes to 3D design. Everyone from video game makers to the fashion industry are currently using 3D to create everything from avatars to product samples that help to limit a company’s carbon footprint and decrease production costs by replacing physical samples with digital ones. Before we get deeper into how to use PBR as a 3D designer and how PBR is helping business owners capitalize on making realistic 3D models of their products, let’s discuss what exactly PBR is and what makes it so important.
What is PBR and Why is it Important?
PBR is a texture workflow that helps 3D artists simulate how light and shadows would react with a 3D model in a real-life environment. This helps to recreate the realistic texture of objects which is especially important for businesses who are showcasing their products in 3D — no matter the industry. When consumers go to purchase a product, they also want to know exactly what they are purchasing, so the more realistic a 3D model can be, the better. PBR has become somewhat of a standardised methodology when it comes to texturing 3D models. This is a great help for 3D designers. Taking textures and 3D models from one program to another can often be a hassle and time-consuming to say the least. PBR becoming a standardised methodology has allowed models to react consistently to lighting across platforms, saving a lot of time for designers and money for business owners.
PBR is a must-know technique for 3D designers
PBR is used widely in many things that consumers interact with each day including most 3D software and game engines. Unreal Engine and Unity both use PBR methodology. It’s also becoming the standard for 3D on the web. Considering how commonly this method is used it is a must-know for 3D artists, today. Before PBR, when an object was rendered with shadow techniques, etc, and then the object was placed in a scene, the object would look nothing like when it was created. It simply would not react the same way! 3D artists would have to make different shaders for each scene. With PBR these renders now react in a realistic way automatically — without the added manual effort.
There are two types of PBR Workflows
For 3D digital artists learning this method, it’s important to know that there are two different PBR workflows. Those workflows are the Metallic Roughness workflow and the other is the Specular Glossiness workflow. Check out this great article on Metallic Roughness and Specular Glossiness workflows if you’d like to learn more. Although different, both give the same result. Another great convenience is that both workflows are supported by most render engines, big game engines as well, and 3D on the web.
V-Ray Materials vs Real-time PBR materials
As we mentioned above, PBR refers to a type of workflow for creating 3D materials that approximate the same way they would react to light in the real world. While it’s true that you can use PBR materials in different environments like games-engines or the web, it’s important to note that not all PBR materials are the same. For example, V-Ray is a rendering engine that also has materials known as V-Ray materials. V-Ray materials are very high-quality and photorealistic. However, these materials can only be rendered using the V-Ray render engine or a plug-in that allows another application to render them properly. V-Ray materials are especially popular in the furniture industry in apparel when displaying high-detail elements such as fur (or faux-fur, preferably). The reason it’s important to know this is that if you are using V-Ray materials (even if they are PBR materials) to render out images, you cannot use those same materials in game-engines, 3D on the web, or in augmented reality.
Generally speaking, when someone is asking for PBR materials, they are not usually referring to V-Ray materials or something similar, instead they are referring to real-time PBR materials. These materials are not proprietary and can be used virtually anywhere.
Limitations on PBR when using 3D scans
One of the big challenges in 3D today is how to create 3D scans quickly and easily that are of a high enough quality to be used on eCommerce sites. While this technology is getting better and better, and major tech companies like Apple are making it easier than ever to capture 3D models on your phone, the textures that are generated are not PBR. The reason behind this is that when you are 3D scanning an object, you are essentially taking many photos of it and having an algorithm stitch those photos together to form a 3D object. Because you are capturing photos, whatever lighting exists in those photos will be persisted in the 3D model. This means that it will be difficult for the materials to react the same way a PBR material would in a different lighting environment. This is honestly perfectly acceptable for many channels like eCommerce and augmented reality but for higher end applications like game engines, scanned assets can be problematic.
PBR is an extremely valuable workflow to use when creating 3D assets, but it’s important to understand how you plan on using those assets in the future to ensure that you are using the PBR workflow that best meets your needs. It’s also important to note that having a beautiful PBR model isn’t enough if you want to take advantage of using 3D in eCommerce and AR. You’ll also want to make sure that you’re using an optimized 3D file (small enough and in the right format) so it can load quickly for customers and meet the specs of whatever platform you are using.
At VNTANA we automatically optimize and convert 3D files for just this purpose! We also provide 3D web viewers with built in AR that can be easily embedded onto an eCommerce website. Contact us to get started!